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WW2 British Prototypes

A.11.E.1 Infantry Tank Matilda Prototype

British Empire (1934)
Infantry Tank – Single prototype

Of all the tanks in WW2 which may be derided or even mocked for being ‘ugly’ or useless, one which invariably makes the list is the British A.11 Matilda. This is partially the result of the overall poor showing of the British Expeditionary Force (B.E.F.) in France in 1940 and partially because of the strictures placed upon the design of the vehicle in the first place. It is also because the vehicle is generally not well understood and its combat record unappreciated.

The only people who really appreciated that latter element were the Germans in 1940, for whom the A.11 and its big brother, the A.12, came as a well-armored and unpleasant shock.

Whilst the A.11 was only in service with the British Army for a few years, it left a mark in the form of one of the most successful tanks of the whole war – the A.12 Matilda.

Misunderstood and underappreciated, the A.11 started as a scribble and resulted in a small, heavily armored tank which proved to be a shock to the Germans at the Battle of Arras in France in 1940. There, in conjunction with infantry and its replacement – the A.12 Matilda, the British succeeded in blunting the nose of the German advance. The A.11 Matilda seen in that battle, however, started with a special and slightly different prototype – the A.11.E.1 (A.11, Experimental model 1), with a history all of its own.

Origins

The A.11 ‘Matilda’ has its origins in the late interwar period, as the British Army was undergoing some head-scratching over not only the shape and dynamics of a future war but also how it would organize itself and what it needed to fight it. The British were generally cautious with new developments in tanks, due in no small part to the trauma of WW1, with the huge losses of men and equipment, and also to the significant limitations on expenditures as the British Empire sought to reconcile the cost of defending Europe from Germany.

Any new development, therefore, had to meet both a developmental limit, the new needs of the Army, and the strict budgetary constraints in force. Luckily for the British, these highly conservative restrictions matched with the equally austere Sir Hugh Ellis, Master General of Ordnance (M.G.O.) and Major-General A. E. Davidson as Director or Mechanisation (D.o.M.). Both men were skilled and competent in their field, with Davidson also a respected engineer, but both still saw future war along the lines of the last one.

In debating the primary role of a new tank for 1934, it was thought that it had to support infantry (an ‘I’ or ‘Infantry’ tank) in the attack against enemy infantry and positions. Enemy tanks could be dealt with by artillery, so a new tank really just needed heavy protection from enemy infantry and anti-tank guns as well as the means to deliver machine-gun fire. As it had to support infantry at their pace, the speed was almost irrelevant. As these two men debated their plans for what a new tank needed to be and how it should work tactically, they consulted with Major-General Percy Hobart, who was Inspector of the Royal Tank Corps (R.T.C.) at the time and proposed two solutions:

  1. A small tank with a crew of two men armed with machine guns built in large numbers to swarm the enemy.
  2. A heavy tank with a cannon.

The solution selected was the first one and, in October 1935, the legend of vehicle design, Sir John Carden, was approached to develop this idea. A skilled engineer and talented vehicle designer, he was also the head of tank design at Messrs. Vickers Armstrong Ltd., meaning whatever he designed, he could get into production quickly.

Sir John Carden, the brains behind the A.11 (Centre) seen on 3rd October 1935 at Heston Airport.
Source: Flight Magazine.

His rather crude initial sketch, finished on 3rd October 1935, was for this two-man small tank with a single turret and a single machine gun. A week later, this sketch was taken by Sir John Carden to Colonel M. A. Strudd, the Assistant Director of Mechanisation (A.D.o.M.). Being a technically simple vehicle and with no concerns over getting it into production in the time scale the Army was planning, just 6 months, it was approved as a project under A-vehicle number A.11. One thing not mentioned in most histories of the A.11 is revealed in that original sketch – the crossing of trenches by the vehicle was an important point, which perhaps hints at the sort of warfare terms about which the Army was still thinking. This new tank would manage to cross an impressive 8’ (2.4 m), more than adequate to cross any standard infantry trench.

Sir John Carden’s original sketch of the A.11 shows a low and long vehicle with a small cylindrical turret and, clearly noted in the corner, a protection level of 60 mm. Note the trench crossing width is clearly shown as 8’ (2.4 m).
Source: Fletcher

It is commonly repeated online and even in some books that the ‘Matilda’ name was selected after the prototype was seen ‘waddling’ like a duck. The connection between Matilda and Duck is unclear in itself in this false history especially, as that particular Disney character with that name only appeared after the war. The name could, of course, not have been penned after seeing it move, as it is first written down on 10th October 1935, when the tank was not much more than a doodle. In fact, ‘Matilda’ was just a company name for the project – a code word to disguise what the vehicle was, although officially it remained just ‘A.11’.

The price of the project, at a time of small defence budgets, however, was somewhat extraordinary, some £15,000 for all of the development and draughting costs. In 2020 values, this is over £1m and each tank was projected to run at £5,000 (£364,000 in 2020 values). For a tank armed only with a small machine gun, this was still very expensive. This is a vehicle often referred to as cheap being built to a budget. For sure, it had a budget to be built to, but it was by no means a miserly one. For reference, a small light, machine gun (or even cannon-armed) tank from the same firm, like the Vickers Light Patrol tank, was on sale in 1933 for just £700 (around £51,000 in 2020 values). It is hard, therefore, to square quite why this Infantry tank might justify costing more than 7 times what that tank would.

Vickers Light Patrol Tank seen in 1932. The same prospective armament at 14% of the cost of an A.11.
Source: Beamish Collection
Vickers 6-ton Mark A tank. The general lines and shape of this tank show a clear line of thought carried across to the A.11.
Source: The Tank Museum, Bovington

Armor

Armor for this new type of tank was going to need to be heavy – very heavy for the era which given that even 20 – 30 mm or so was considered good protection for many tanks is saying quite a bit. A standard thickness of 60 mm was proposed for the tank, with the plate made from Vibrac 45 armor steel produced by the (Vickers) English Steel Corporation. The roof and floor plates were eventually to be just 10 mm thick and made from Homogenous Hard tank armor and proof against .303 rifle fire. Originally, however, for the prototype, the hull was not going to be made from armor plating, but mild steel ‘soft plate’ instead. On A.11.E.1, the rear and hull roof were made using thinner plates than that used on the eventual production models, just 7 mm thick for the floor and roof and 8 mm thick at the rear – albeit heavily sloped.

This is common enough in a prototype tank, as it makes manufacturing easier and cheaper and permits modifications to be done quickly prior to production. Of note too is that this prototype was only made in plate 60 mm thick, as this thickness was considered sufficient protection against the primary prospective enemy anti-tank weapon of the time – the excellent German 37 mm gun (3.7 cm Pak 36).

Factory fresh German 37 mm anti-tank guns. Source: Rheinmetall

Despite having the appearance of a tank riveted to a frame, like many other tanks constructed in this period, the structure was physically strong and stiff enough that it was, in fact, simply riveted together without a frame.

Prototype – A.11.E.1

Despite being a technically simple vehicle, this first vehicle, A.11.E.1, now with an official War Department index number of T.1724, was not finished until September 1936, when it was handed over to the Mechanisation Experimental Establishment (M.E.E.).

A.11.E.1 seen shortly after delivery in September 1936. Of note are the lack of exterior fittings on the hull, such as lights and stowage boxes, with the exception of a cranked tubular tool mounted on the front half of the left side, parallel with the track. This photo shows to a good level of details of the original rubber-tyred return rollers and the toothed idler wheel at the front.
Source: Beamish Collection

Firstly, on 9th December 1936, splash tests were conducted at Farnborough and the turret, in particular, was found to be a problem. Here, under concentrated machine-gun fire using standard ball ammunition, it was found that the mantlet could actually break up under the stress of multiple impact and allow splash to enter the vehicle, to the detriment of the crew. As a result of this, Messrs Vickers-Armstrong replaced the mantlet with a cast steel mantlet which would chip away under the repeated stresses of concentrated fire, but would neither jam nor break up.

Some three months later, on 16th March 1937, armor plating 60 mm thick of the type intended for the primary armor was tested at Shoeburyness. Here, it was found that, whilst 60 mm rolled plate and 60 mm castings were sufficient to stop armor-piercing shots from the British two-pounder, there was not sufficient additional protection to allow for a sufficient margin of safety. As a result, the armor was recommended to be upgraded to a new requirement 65 mm thick with a tensile strength of 75 tons (76.2 tonnes) for production vehicles.

Further splash trials were carried out in November 1938 and, once more, there were problems. Specifically, splash could enter through the large driver’s hatch as well as through the engine louvers. On top of this problem, the bullet-proof glass selected by Vickers had the unpleasant characteristic of splintering when shot and had to be replaced. Quite why this testing process had to be dragged out over a nearly two-year period when the whole tank was needed ‘within 6 months’ is somewhat unfathomable. Nonetheless, the lessons from the trials meant that modifications to both thickness and splash protection were made between A.11.E.1 and production A.11 models.

Most noticeable are the changes around the driver’s area. On the prototype vehicle, the sidewalls of the hull are straight and cut flush with the surface. This created a sharp edge and provided no angling to reduce splash from small arms, which could go towards the driver’s hatch. These top edges of the side were therefore chamfered at roughly a 45-degree angle. Likewise, the tendency for splash to penetrate the leading lip of the large hatch was rectified with a protective strip riveted to the top edge of the driver’s panel. An additional change was the addition of a pair of horizontal raised strips across the full width of the glacis. These ribs would stop rounds that struck the glacis from ricochetting up into the direction of the driver’s visor or hatch edge. One splash guard which was later to be modified from the A.11.E.1 design, however, was the one that ran across the width of the hull roof in front of the turret. By the time the vehicle entered production, this was not as high and just covered the bottom edge of the turret.

Comparing the hull front around the driver’s area from A.11.E.1 (left) to a production A.11 (right) highlights the findings from the splash trials. The chamfering of the vertical side armor is obvious, as is the splash guard on the driver’s plate. Noteworthy too are the horizontal splash guards across the glacis plate to further reduce the problem.
Source: IWM

Layout

The vehicle itself was very simple in arrangement. With just two crew, the driver sat centrally in the front, operating the steering and propulsion via levers and pedals. Behind him, and manning the gun as well as commanding the tank, was the second crew member, the commander. Both these men occupied the small yet adequate fighting compartment and were separated from the engine by an internal bulkhead. The driver sat forward in the hull and was provided with a single, full hull width rectangular hatch above him. This large hatch was supported by two hydraulic cylinders due to its weight. No episcope was originally fitted to A.11.E1., but this was added during testing. Without it, the driver was limited to just a narrow view directly ahead when the hatch was closed – with it, he could provide additional situational awareness to the sides.

The rear of the vehicle sloped sharply downwards over the engine bay. Perhaps the most distinctive feature of the A.11 was the lack of mudguards over the top of the track run. This is surprising given how simple such a guard would be, whether in metal or even canvas (like the Medium Mark A ‘Whippet’ from WW1). The lack of a mudguard meant dirt and branches could be caught up in the tracks and dragged along the side of the tank or thrown up onto the engine deck, none of which would improve either the mechanical or combat efficiency of the tank. The only effort to prevent such a situation were rather small and sturdy guards fitted only over the rear-drive sprocket, which was a feature of the production vehicle – another lesson from A.11.E.1.

Left side view of A.11.E.1 providing an excellent study of the suspension bogies, with the two pairs of wheels on spring leaves connected to a central support with a return roller above and integral to them. Note the toothed front idler has already been replaced and the low position of the front stowage box ahead of the leading bogie. Note that the addition of the stowage boxes has moved the tubular tool to the rear half of the hull. The flattened end of the tool is visible next to the rear sprocket.
Source: IWM

Size

Overall dimensions for A.11.E.1 were very much those of a small tank. Just 15’ 11” (4.85 m) long and 7’ 6” (2.29 m) wide from the outer track edges, with the track centres 6’ (1.83 m) apart. Overall, the top of the turret was barely 6’ (1.83 m) from the ground – an ideal size to cover a man advancing behind the tank. By the time the trials had ended, this increased to 6’ 1.5” (1.87 m) to the top of the episcope on the turret roof. Ground clearance was also very reasonable, measuring some 9.5” (240 mm) from the ground. For the sake of reference, this meant that the A.11 was shorter in length and height, and only slightly wider than the already small Renault FT of WW1.

Oddly, the trench crossing idea of managing to bridge an 8’ (2.4 m) wide trench from the original plan had been abandoned. The final design would manage just 6’ 6” (1.98 m), still enough to cross a normal infantry trench or a small ditch, whilst also keeping the overall length (and thereby, weight) of the machine down. Climbing performance was also acceptable, as those exposed tracks projecting from the front of the tank could easily grip onto a surface to help it climb a parapet or low wall, as long as it was no higher than 2’ 6” (0.76 m) high.

One other consideration in obstacle crossing for the design was the main armament, which, because it did not project, added zero risk of it becoming lodged in the bank of a ditch the tank was entering, as would be an issue with a long-barrelled weapon. That is not to say that the weapon in its armored cowl did not cause obstructions, because it did. It fouled on the driver’s hatch to the extent that, with the gun forward, the driver was not able to have his hatch fully open. No official fording capacity was noted in official data for the A.11.

Fittings

Every tank has to provide some external fittings and items for practical purposes, like lamps, so the vehicle could operate at night, or stowage for crew items externally, in order to free up internal space. The A.11.E.1 was absolutely no different but was supplied bare. No lamps, no boxes, almost no tools and this would indicate that the intention was to find a location during the trials.

Soon after trials started, these fittings started to appear, with a pair of odd-looking boxed-in headlamps fitted on stubby arms which projected from the sides of the hull, just level with the front of the turret.

The almost bare A.11.E.1 during trials, showing that the turret roof arrangement had yet to be decided, as it was completely absent, and that no episcope had yet been fitted to the driver’s hatch. The first of many modifications can, however, be determined, with a wing mirror fitted to the front right hand side to assist the driver in seeing behind him and with the pair of boxed-in headlamps on either side.
Source: The Tank Museum, Bovington

With the first essential fittings added – those necessary to drive the vehicle safely, then followed the turret roof, with a boxy style of episcope and a rotatable episcope fitted into a hole cut in the front angle of the driver’s hatch. These two additions provided much-needed situational awareness for the crew. As the first suspension changes took place, so too did the stowage on the tank, going from none to two large boxes placed low (so as to not block the driver’s view slit) on either side of the driver’s compartment. The final change or addition during testing was the result of the lack of mudguards. For whatever reason these were left as just small and somewhat flimsy sheet metal covers which only went over the sprockets and no further. By the time the tank would enter production, some additional modifications took place with those lessons learned from A.11.E.1, like changes to the stowage and headlamps, plus additional features, like smoke grenade launchers on the turret, fire extinguisher mountings, and tow cables, but the essentials of the tank were sound.

The boxed-in headlamps in their protective casing would be changed too – standard car-type headlamps could be used instead. They would be easily damaged by enemy fire or even passage through heavy scrub but they were also cheap, simple, plentiful, and easy to fix.

One non-essential item which was added as almost an afterthought was a mine plough designed by the firm of Fowler. The Fowler coulter plough (coulter is not a company, but a vertical blade in front of the ploughshare itself), as it was called, was a somewhat ungainly device consisting of a pair of long arms formed from steel girders, with one on each side of the tank. Operated up and down from travel position to a deployed position via a drum-driven chain from a power take-off on the back of the transmission, the plough could be lowered so that the wheels on the ends of the arms ran along the ground surface.

A tubular framework projected ahead of the main frame, which ensured the plough followed the terrain ahead and kept scrub from clogging the front of the device. Behind this was a set of coulters on each side, which would cut the ground and ploughshare the dirt and any mines concealed within it to the left and right of the tank’s route. This was first tried on A.11.E.1 in 1937 and was found to be highly successful, to the extent that the necessary fittings for such a plough were then added to the first production A.11 tank, although, by then, the need to get tanks off the production line was more important than a rather complex device which had never been part of its original purpose.

A.11.E.1 showing the original Fowler mine-plough in use. Note the absence of the tubular framework on the front. Source: The Tank Museum
The modified Fowler mine plough, as fitted to the first production A.11. but first trialled on A.11.E1. Source: IWM
A.11.E.1 during trials. It can be seen that the episcopes still have not been added to the driver’s hatch or turret roof, but that the toothed front idler has already been removed. Of note is the unusual shelf stowage concept on the upper right of the hull for what appear to be metal ammunition boxes. This does not appear later and appears to have been a failed modification which had been trialled.
Source: IWM

Suspension and Tracks

The original sketch from Sir John Carden showed suspension substantially different from the ones which the vehicle was subsequently built with as a prototype. In the provisional sketch, there are clearly 4 distinct and separate bogies, each with a pair of road wheels and with a spring connected to the hull and the rear of each pair. Above each bogie was a track return roller. The system drawn closely matched that of the Dragon Mark IV Artillery Tractor produced by Vickers-Armstrong. It was almost certainly meant to be based upon that system. Just like that system, the tracks used were a medium pitch design made from cast manganese steel and connected together via a single steel pin. Each link also featured no rubber pads for use on roads, but a pronounced spud to gain better traction on soft ground.

However, when the vehicle was produced, it would not use this Dragon or Dragon-like Horstman suspension, but a different Vickers product derived from the suspension of their 6-ton tank.

As a matter of some confusion in the tale of the suspension for these vehicles, there are multiple marks of vehicles and there are several distinct suspension variations worked through on Vickers products at the time.

In essence, however, this proposed suspension consisted of a pair of bogies with a flat arrangement of 4 pairs of road wheels, each mounted in pairs. Each of those pairs was connected to one end of the spring leaves, providing a degree of movement, as the entire bogie could also rotate around a central pivot point. The design was complex. Using small wheels, whilst allowing them to be placed closer together, also resulted in a small external unit that was easily clogged with mud. This style of suspension had already been rejected by the M.E.E. as a problem, so it can only be surmised that it was added as a cost-saving measure, as it was already in production.

A.11.E.1 seen after modification from its first trials.
Source: IWM
Rear three-quarter view of A.11.E1. bearing the vehicle registration mark (VRM) CMM 880. The heavily sloped rear deck is readily apparent. The arrangement of the back was modified to provide additional protection from small arms fire on the production vehicles.
Source: IWM
Production A.11 Matilda showing the change in the shape of the armor plating over the rear deck. The relocation of the exhaust from the centre of the rear to the right side is also shown. Photo Credit: Craig Moore

If there is criticism of the A.11, it has to focus mostly on this decision of choosing a system based on an idea from 1929 which the Army already disliked and had proven to be disappointing during testing. This was not a decision likely to find supporters, yet the solution was available and in production and it did work to the extent required. Pragmatism meant the suspension, as fitted, would be kept and that tweaks would have to be made just to make it work.

As it underwent testing at M.E.E., various problems were quickly identified and one of the first was that the toothed front idler was unnecessary. Further, the track was found to be collecting stones and these could become jammed in the rear sprocket. The solution to the former problem was simple – just replace the toothed idler sprocket with a non-toothed one. The latter was resolved in April 1937 and consisted of raising the rear sprocket by 5 inches (127 mm). This would not be the final change to the suspension of the A.11 during its service, but the A.11.E.1 had set the shape and suspension type which remained with the A.11 throughout its military career.

The hull production had changed too. The original sides of the A.11, as seen on A.11.E1, were a simple two-piece fabrication with an offset vertical line of rivets about halfway down the length. On the production vehicles, this seam was retained, but the rearmost panel was now two panels which also had to be riveted together. This added a little weight to the vehicle, but also simplified production by reducing the amount of cutting of the thick armor plating which was required. Rivet-counters will also note that the front of the tank shows a different layout of rivets as well. On A.11.E1, the nose of the tank was a separate panel and bolted onto the tank with a column of four bolts on each side. The glacis plate was likewise bolted onto the tank and the nose plate was changed for production. In production, the flat edges of the glacis plate were chamfered and riveted to the structure of the tank. The nose plate was now integral with the extensions either side of the front idlers and all riveted in one piece to the front of the tank.

Radio

No radio was fitted to A.11.E.1, presumably as a cost and complexity saving measure. Right from the outset, in 1935, no wireless set had been planned for A.11. This would be rectified by the time the tank entered production, as the Wireless Set No.11 was available by 1938 and would eventually be fitted as standard on all production tanks, although this would obviously add weight and take up valuable space inside.

Trials

Other than the already known problems with the suspension system chosen, the A.11 had a remarkably easy birth when it came to testing. The exhaust pipe being moved was just one of those small changes identified during testing to avoid problems in production vehicles. Indeed, that was the entire purpose of testing and the A.11 can be considered to have tested out very well.

Stowage

The two large stowage bins fitted to A.11.E.1 were varied for production models but remained essentially the same – two large boxes, either side of the hull. On the A.12 vehicle, which followed the A.11, these stowage bins were moved forwards and downwards to flank the nose of the tank. Behind the curved front armor of the A.12, those front bins actually provide a misleading shape on the front of the A.12, giving it a full-width flush appearance when it is, in fact, a narrow nose-shape just like the A.11. Moving those boxes forwards in that manner and making them integral with the vehicle also provided the advantage of some additional protection for the A.12.

Engine

Power for the A.11.E.1 was provided by a 3.62 litre Ford V8 petrol engine delivering 70 hp connected to a Fordson four-speed crash (manual clutch) gearbox. Drive for the 11.5” (292.1 mm) wide manganese steel tracks was delivered from this gearbox via final drives at the rear, connected to the sprockets. Steering was provided through a system of clutch and brake steering (i.e. brake the right track to turn right and vice versa), which was taken directly from the Vickers light tank and controlled by the driver in the same manner – a pair of steering levers. One problem identified during testing was that the exhaust pipe from the engine was prone to cause the engine oil to heat up, so it had to be rerouted, but this was a simple affair and certainly not a failure – just a tweak to avoid a problem. It meant a very minor external change of the exhaust from the rear deck at the bottom in the middle to the right-hand side of the back instead.

Cramped is one word – an efficient use of space however, might be another explanation for the very tight fit of the 3.62 litre Ford V8 70 hp engine in the bay. The incredible thickness of the armor can be seen on the left on the top of the exposed side plate. Note that the cable seen at the top is a hatch release for the engine deck connected to the catch at the top left of the photo – it could only be released from inside the tank. Source: Fletcher

The engine was small and the result was a relatively slow vehicle. However, this did not matter. Indeed the A.11.E.1 proved to be faster than expected and perfectly satisfactory for speed. From the notes of Col. Strudd at that 10th October 1935 meeting with Sir John Carden when the tank concept was presented, it is clear that the Army was perfectly satisfied with a top speed of just 5 mph (8.0 km/h) although 8 mph (12.9 km/h) would be better. The A.11.E1., could, in fact, achieve a top speed of 10.9 mph (17.5 km/h) on a road and 5.8 mph (9.3 km/h) off-road, but this was not a problem at all for the design, as it only had to keep pace with infantry on foot. The average speed the tank could sustain on a road was 8.17 mph (13.1 km/h) and 5.6 mph (9.0 km/h) off-road.

The internal fuel tanks held 43 Imperial gallons (195.5 liters) of petrol for an official maximum operational range of 80 miles (129 km). With 43 litres of petrol and a known fuel consumption rate during the trials of 2 gallons (9.1 litres) per hour on-road and 1.8 gallons (8.2 litres) per hour off-road, that also meant up to 21.5 hours of road use and 23.8 hours off-road.

Turret

Made in a single piece, the turret was a substantial casting with armor 60 mm thick all round. Provision was made for a single armament – either a Vickers .303 caliber machine gun or the somewhat beefier .50 Vickers instead.

Almost cylindrical in shape, the basic elements of the A.11 turret were the same as drawn originally by Sir John Carden. The cylinder was angled at the back, providing a little more space, and the front carried forwards the trunnions for the main gun, all within this one-piece casting.

Atop the turret was a simple circular hatch which opened in 2 pieces – two quarter circles at the rear half, forming a semicircle, opened out and the whole front half of the turret roof formed the other semi-circle. On the left side of this front half-circular hatch was the single episcope for the commander.

Turret roof of T.3347 showing the unusual split hatch. Source: Chris Stillito, Armour in Focus

The original turret casting for A.11.E.1 was a little more complex than on the production model. The outer edge on the front half of the turret at the top is the reference point for spotting the difference. On the prototype, there is a pronounced half-rim running around the front of the turret and projecting from the sides. This is not easily visible on the production turret, which replaced this hard rim with a more rounded and less pronounced outswell, although the purpose was the same – to reduce the chances of ricochets up the sides of the turret hitting an exposed commander. The turret was also asymmetrical, with that rear swell offset to the right at the back and the front casting for the armament offset to the right as well at the front. This meant that the trunnion mount can be seen on the right-hand side of the turret but not on the left and the reason for this offset is obvious – it allows the commander to share space with the gun. With the primary (and only) weapon on the A.11 being the single machine gun, it was belt-fed from the left, so setting the gun off slightly to the right allowed the commander to operate the gun and reload it much more easily.

The rear of the turret would noticeably change from A.11.E.1 too, from a rounded back on the prototype to the production turret which angled-off the swell at the back of the turret and created a short ‘step’ underneath – a very modest change to create a little extra space inside.

The rear of the A.11.E.1 turret (above) differs noticeably in shape from the rear of the production turret (below)

Two more small features of note on the turret which would change from A.11.E.1 would be the addition of a small triangular bracket for mounting a radio antenna base on the rear right-hand side for the No. 11 Wireless Set inside, and the addition of a pair of mounts for the smoke grenade launchers, one on each side of the turret and operated by cable from inside. Both the addition of a radio and smoke grenades would be substantial improvements from the very basic tank which was A.11.E.1.

Armament

A.11.E.1 was intended to support infantry by providing not just a mobile protective shield in front of them, but also to suppress enemy positions with machine-gun fire. The machine gun, not the cannon, was the primary choice for killing enemy troops and destroying machine-gun positions, which were a major threat to the infantry. For A.11.E.1, the original weapon chosen was simply the standard water-cooled .303 calibre Vickers machine gun albeit, with a short note which followed saying “we can try our idea of M/C gun but this is not so urgent”.

‘M/C’ in this context may be taken to mean ‘Machine Cannon’ i.e. a heavy machine gun with added anti-armor capability over the standard .303 machine gun or another compact gun capable of firing a small high explosive charges as well. The details were clearly not finished, as the priority was to get the tank into development as soon as possible. The small turret would make the fitting of a larger gun harder but not impossible. For the development of the A.11, just two guns were selected, either a .303 calibre Vickers machine gun or its heavier brother, the 0.5 calibre Vickers machine gun. Whatever ‘machine cannon’ Sir John Carden and Colonel Strudd were discussing in October 1935 is not known.

Vickers .303 calibre Mark IVA machine gun.
Source: The Vickers Machine Gun
Vickers 0.50 calibre Mark V heavy machine gun
Source: The Vickers Machine Gun
Armament Options for A.11
Gun Vickers Mark IVA Vickers Mark V
Caliber .303 0.50*
Muzzle Velocity 744 m/s 760 m/s
Weight (vehicle mounted) 65 ½ lbs. (29.7 kg) 71 ¾ lbs. (32.5 kg)
Rate of fire 500 650-700
Belt size 250 rounds 100 rounds
Note * 12.7 x 81 mm (.5 Vickers also known as the ‘.5V/580’) rather than the 12.7 x 120mm (0.5 Vickers High Velocity also known as the ‘.5 V/690’). The number after the ‘V’ in both cases referred to the weight of the bullet in grains rather than a velocity

Both types of machine gun were available with a variety of ammunition, from a lead core ‘normal’ bullet suitable for general use to an armor-piercing round. When it comes to the common complaint about the A.11, that it was under-armed, the existence of armor-piercing ammunition for both guns has to be taken into consideration.

For the .303 caliber gun, armor-piercing rounds had been available since WW1, as had incendiary rounds. The Mark.VII.W.z Armour Piercing round of 1917 (known later as the W Mk.Iz from 1927) was a 174 grain (11.28 gram) cupro-nickel jacketed bullet with a 93 grain (6.02 gram) steel tip. Traveling at 762 m/s, the bullet was designed to meet a requirement that 70% of rounds could penetrate a 10 mm thick armor plate at 100 yards (91.4 m). An effective anti-armor range of 100 m does not sound like much, but was perfectly adequate to deal with close-by enemy positions and also for suppressing protected targets further away.

For the 0.5 calibre gun, the armor-piercing round was known as the ‘Armour Piercing W. Mark 1z’ and also featured a hardened steel core. The penetrative requirements for this round were that 7 times out of 10, it would be able to penetrate 18 mm of armor plate at 0 degrees and 15 mm at 20 degrees vertical, all at 100 yards (91.4 m). A tracer version of this round, known as the SAP Tracer FG, came in various marks and there was even an incendiary version of it, known as the ‘Incendiary B Mark I.z’.

Whilst the .303 was an ideal weapon for suppressing enemy positions, mowing down enemy troops and dealing with soft-skinned vehicles, it was not suitable for picking off enemy forces behind a shield, like a gun crew. It was also not suitable for dealing with light enemy armor. The option of mounting the .50 calibre version removed that problem at short ranges. Both guns were perfectly adequate for general work, with acceptable accuracy on target out to at least 1,500 m. Both versions were virtually indistinguishable from each other when fitted into the turret and concealed within the large cast armor housing over the water-cooling jacket, although only troop leader’s tanks were fitted with the 0.50 calibre.

Some 3,000 rounds (12 belts) of .303 caliber ammunition were eventually to be carried as standard, which would be sufficient for just 6 minutes of continuous automatic fire. In the trial photos, there is one which appears to show half a dozen ammunition cans on a shelf on the right hand side. Assuming this was an attempt to carry more ammunition, then that would be several more belts for perhaps as much as 5,000 rounds carried. Boxes for the .50 Vickers ammunition held just a single 100 round belt, such was the greater size of the round. Assuming the ammunition stowage for both guns was to be proportional, this would mean 1,200 .50 Vickers rounds, enough for just 2 minutes of continuous fire.

Production

A contract for the production of 60 tanks was signed at the end of April 1938 and, ten days later, another order for the same amount came, meaning a total of 120 tanks. This would be enough to provide tanks for 2 whole battalions.

Conclusion

The A.11.E.1 was a successful prototype. It arrived late and perhaps this was partially the result of the untimely death of its creator, Sir John Carden, in December 1935 in an air crash. Certainly, there was nothing particularly novel about the tank or some new technology that had to be invented for it to exist.

The A.11.E.1 occupies an unusual space within British tank design too, as it languished in that period in the 1930’s where a new weapon was needed, but not one was entirely sure on what they were really going to need. Nonetheless, the design was still capable of being modified from its original form into something a little more than that and of being a capable platform for a device like the Fowler mine plough. The reality for it was that, by the time it was in production and being delivered, there was already a replacement in the pipeline in the form of the A.12 Matilda. That particular vehicle had a much more difficult birth and yet it could not have existed in its final form without the A.11 beforehand. The heavily armored infantry tank which started with A.11 and its prototype A.11.E.1, became the foundation of the heavily armored A.12 and its most dominant feature. The A.11.E.1 should, therefore, not be seen as some retrograde step for the Army to some attempt to rerun the First World War, but an attempt to learn from that war and produce a tank sufficiently protected for the next one.

The first production A.11 off the production line. In this head on view, the offset of the machine gun to one side is evident, as is the very narrow profile the tank presents front-on to an enemy. Source: Fletcher
Matilda A.11.E.1. Illustration by Stoneheartisk.
Top view of the Matilda A.11.E.1. Illustration by Stoneheartisk.
Rear view of the Matilda A.11.E.1. Illustration by Stoneheartisk.
Right side view of the Matilda A.11.E.1. Illustration by Stoneheartisk.
Front view of the Matilda A.11.E.1. Illustration by Stoneheartisk.

 

Specifications A.11.E.1

Dimensions (L-H-W) 15’11” (4.85 m) Long, 7’ 6” (2.29 m) wide, 6’ 1.5” (1.87 m) high
Engine 3.63 litre Ford V8 petrol producing 70 hp
Speed top speed 10.9 mph (17.5 km/h) on road and 5.8 mph (9.3 km/h) off road, cruising speed 8.17 mph (13.1 km/h) and 5.6 mph (9.0 km/h) off road.
Armament .303 or 0.5 Vickers machine gun
Crew 2 (Driver, Commander/Gunner)

Sources

Fletcher, D. (1991). Mechanised Force. HMSO, UK
Fletcher, D. (2017). British Battle Tanks. Osprey Publishing, UK
Foss, C., & McKenzie, P. (1988). The Vickers Tanks. Haynes Publishing, UK
Forty, G., & Forty, A. (1988). Bovington Tanks. DPC, UK
Brown, P. (2014). 1 ATB in France 1939-40. Military Modelling Vol.44 No.4. 2014
Brown, P. (2014). 1 ATB in France 1939-40. Military Modelling Vol.44 No.5. 2014
Solarz, J. (2008). Matilda 1939-1945. Tank Power vol. LXI. Warsaw, Poland
Obituary, Sir John Carden. Flight Magazine, 19th December 1935
Tank Training Vol. II Part III Pamphlet No.2 .303-IN., Vickers Machine Guns Marks VI, IVA, IBV and I. (1936). HMSO, UK
Tank Training Vol. II Part III Pamphlet No.5 .5-IN., Vickers Machine Guns Mark V. (1937). HMSO, UK
War Office File 194/44 Matilda Infantry Tank, September 1936
War Office File 291-1439 British Tank Data
Williams, A. (2012). The .5” Vickers Guns and Ammunition. https://quarryhs.co.uk/Vickers.html

Categories
WW1 US Prototypes

Roy / Lzarnopyski Infantry Fort

USA ww1 USA / Austria – 1919
Infantry Fort – None built

World War One was, by 1918, the largest and most costly war in terms of lives in the history of mankind. Starting in 1914, the war finally ended officially in June 1919, with the signing of the Treaty of Versailles, although, with the signing of the Armistice in November 1918, all active combat between the Allies and Central Powers ended. The United States had been late to the war, only joining on the side of the Allies in April 1917. For the period of the war which remained, the US built its own derived version of the Renault FT, changed to suit imperial units, and later, the heavy tank Mk. VIII, which was the product of a joint British / American development.

In the meantime, various inventions and designs were being submitted to the US Government and Army or just espoused in the media. These presented military vehicles of varying degrees of practicality and reality. Probably the last such vehicle to be submitted during the active phase of WW1 was filed with the US Patent office just 2 days prior to the Armistice of 11th November – this was the Infantry Fort of George Roy.

The Men

George Roy described himself as a subject of the Austrian Emperor and submitted the patent in his own name, as the inventor, along with a second man, Piotr Lzarnopyski. Roy assigned half the value of the design to Lzarnopyski, presumably because Lzarnopyski helped pay the required filing fees, as his name appears nowhere else on the patent application or drawing. Both men were identified as residing in Chicago, Illinois, and no nationality was given for Lzarnopyski, although the name is likely Polish in origin. Sadly, neither man appears to have applied for other patents before or subsequent to this one, so very little additional information can be gained on who they were or how they came to the design submitted in their names.

The Design

The intent behind the design was to provide a mobile tracked platform from which soldiers could deliver firepower upon the enemy, as well as be elevated and protected by armor when being transported.

The overall shape is one of a large flattened triangle, with the reverse angle of the triangle formed into a series of steps up which soldiers were to climb from a small projecting platform at the rear. Three steps would bring a soldier to the top fighting platform of the vehicle, from where he could fire from behind cover.

Layout

The triangular body of the vehicle was dominated by the large angled front glacis, which curved very slightly across its width, providing a well-shaped surface to deflect enemy bullets. In the recess of the curve of the glacis was a small curved firing step or platform on the front. At the top of the vehicle, where the glacis met the roof, the roof itself was just the flattened peak of the triangle, forming the top of a wall from behind which men could shoot.

The plan view of Roy’s design is dominated by the features on the left of the small platform and large curved front glacis. Note the use of two small anchors on the right right of the image.
Source: US Patent US1299620 amended by the author.

Behind this was a series of short steps down to a platform at the tail. Within the triangle, formed by the glacis and these steps, was the body of the vehicle, with a single rectangular door on each side. The tracks were arranged in a triangular pattern, with the top flattened. This matched the shape of the body of the vehicle. The track itself appears from the patent to have used pronounced square section timber spuds attached to the links and was pulled around via a sprocket, which was the rearmost of the two wheels at the top flattened part of the track. This drive sprocket was rotated by a simple chain drive from the engine, which was mounted onto a floor frame inside the body of the vehicle. Eight toothed road wheels were arranged evenly spaced on the bottom, against the ground portion of the track, spreading the load of the vehicle on the ground. No return rollers, jockey wheels, guide beams, or similar supports are shown to support the track either on the way up from the front or on the way back down at the back.

The track itself is full width, i.e. there is only this single track rather than one on each side. Power to drive the track does not get delivered via a sprocket on the left or right but via one arranged towards the center of the width of the track.

The flattened triangular arrangement of tracks taken from US Patent US1299620, with the vehicle parts edited out to highlight the track and engine. Source: US Patent US1299620 amended by the author.

Armor

The front of the vehicle was formed from one enormous and continuous glacis, from just above ground level all the way to the top of the tank, forming a door-stop shape. This angled plate would serve to deflect incoming enemy bullets and, whilst there is no armor thickness mentioned – the protection was only ever mentioned to serve against bullets. Thus, a thickness of not more than 8 mm might have been needed to provide the sort of bullet deflection Roy was intending. The steps were meant to be made from bullet-resistant armor plates, as this would allow men or stores to be carried inside the vehicle in safety.

Seen from the front the enemy can only see the enormous glacis plate and the bottom of the full-width track.
Source: US Patent US1299620 amended by the author.

The entire body surrounded the tracks at the front, covering them from enemy fire and likewise at the rear. The sides of the vehicle were protected as well, as this armored covering extended down to the same level as the glacis at the front.

Side view of the vehicle, with the sides shown completely enclosing the sides. The only feature that is drawn is the side door.
Source: US Patent US1299620 amended by the author.

Utility

Roy envisaged the vehicle in use as effectively a mobile armored wall, rather than a fort, despite the name he applied to it. With no sides or rear protection for the men using this as a firing platform, all of the firepower and armor was directed only to its front. Seen from any other direction, it would only serve to provide a series of easy and well elevated human targets for an opposing force to pick off.

Seen from the rear, all there is to Roy’s design is the steps and a full-width hinged door below the top step. A small space inside could store additional ammunition.
Source: US Patent US1299620 amended by the author.

The vehicle was clearly intended to either operate in the attack as a platform, or forming some defensive line with other vehicles, as it could be anchored to the ground by means of a simple anchor operated from the small platform at the rear.

The very simple ground anchor for the vehicle. Two of these were drawn with one on each side of the rear platform.
Source: US Patent US1299620 amended by the author.
The British Pedrail tracked shield of 1915. A poor idea that never saw service and yet was still better than Roy’s design in almost every regard, as it was a smaller, cheaper, and simpler machine providing more cover for soldiers behind it. Source: UK National Archives.

Engine

No form of propulsion was mentioned, other than the single comment describing the vehicle, where Roy stated it was to have a “motor driven track”. Driven from a single, high-mounted sprocket roughly central in the width of the single track, it is unclear how or even if the machine could be steered.

The engine is located slightly off-center, to the right side of the vehicle.
Source: US Patent 1,299,620 amended by the author.

Crew

Roy provided no information at all about any potential crew for the vehicle and, as it was not armed, presumably just a single person would be required to drive it. There is no indication as to where a driver might go, as there are no vision slits or windows provided from which someone inside could see out.

Practicality

On the topic of practicality, there really was none. The design provided zero protection for the men using it as a firestep from either the sides, rear, or above. Any crew would certainly have struggled to control such a vehicle with no clear idea as to how to steer the machine. It seems Roy intended it to be able to go only forwards.

For a period earlier in the war, this kind of naive tracked shield, for want of a better term, might have been forgivable, but the design was submitted in 1918 – more than 2 years after the first tanks had seen combat and long after images were to be found easily in newspapers around the world. There is simply nothing at all offered by this design that was not or could not be delivered better by a tank or something even simpler. Even the tracked Pedrail Shield of 1915 surpassed this idea, as it was simpler and provided better protection. Unsurprisingly, offering nothing at all to anyone, this design never progressed past the patent office.

Roy / Lzarnopyski Infantry Fort. Illustration by Pavel Alexe.

Roy/Lzarnopyski Infantry Fort specifications

Crew 1? (driver)
Propulsion engine of unknown type
Armament none
Armor bulletproof
For information about abbreviations check the Lexical Index

Sources

US Patent 1,299,620 Infantry Fort, filed 9th November 1918, granted 8th April 1919.

Categories
Cold War British Prototypes

Straussler Main Battle Tank

United Kingdom (1960)
Main battle tank – Plans only – none built

Nicholas Peter Sorrell Straussler (1891* – 1966) is perhaps most famous for designing the inflatable floatation screen for tanks such as the M4 Sherman, commonly referred to as a ‘Duplex Drive’ or DD tanks.

Born in Hungary in 1891*, at a time when it was still Austria-Hungary, he had, as a young man, come to the United Kingdom in 1910 or 1911. He may have found work during World War One in one of the hundreds of ordnance factories supporting the war effort. Certainly, he was demonstrating his engineering skills when he filed his first patent in January 1911 for a rotary engine.

(*His UK death certificate indicates a date of birth which could be 1892)

Early Engineering Work

After the First World War, he remained in the UK and applied for British nationality, marrying Edith Arbib in 1923. His engineering skills quickly found purpose and, by 1928, he was running the firm of Folding Boats and Structures Ltd. He was also designing small scout cars both with and without armor, both for domestic use and for export. He was finally naturalized as a British citizen in February 1933.

Clipping from a pre-war advert for the Vickers ‘Straussler’ folding boats.
Source: Pinterest

He would eventually open a small workshop in Brentford, West London, and produced a variety of unusual-looking but highly effective designs in partnership with the Alvis motor company, which proved to be both effective off-road and ruggedly reliable, gaining him some limited production contracts. He continued with armored vehicle design work, operating as Straussler Mechanization Ltd. until it entered voluntary liquidation in 1941 and its assets sold off in 1942. He would marry a second time in 1944 to a woman twenty years his junior, Josephine Vassie, and produce one child, Roderick, in 1945. They divorced or separated in around 1958.

A complicated private life aside, his most famous contribution to the war effort was to build on his work on Folding Boats and create an erectable canvas screen and outboard motor, tested on a Tetrarch light tank in July 1940. By the spring of 1942, this unusual arrangement was accepted as part of the general solution to solve the problem of how to get tanks ashore for an amphibious assault. The Infantry Tank Mk. III, better known as the ‘Valentine’, was equipped with these screens as well. Later, by 1943, the Valentine was replaced as the primary vehicle for ‘Strausslerisation’ using a floatation screen by the Sherman.

That development was a successful addition to the Allied arsenal in WW2 and, clearly, Straussler was keen that this development see wider adoption.

Designing the Ultimate Tank

After World War Two, Straussler continued work as an engineer and was, at some point, inspired to try and design a new type of vehicle. This was to combine two of his areas of design expertise, a screen for helping vehicles cross water, and a highly flexible suspension system allowing for a wide range of movement from track units and wheels alike to improve mobility.

Key features of the main battle tank design were to reflect what he felt were the fundamentals that would be needed from an “ideal” tank, specifically:

  • A vehicle as small and light as possible with a low profile.
  • Screen around the tank to allow it to be amphibious in water.
  • As small a crew as possible.
  • The largest possible primary “heavy caliber” armament, which would be loaded, aimed and fired automatically.
  • As much ammunition as could be carried.
  • The ability to mount alternative or additional weapons as may be required or desired.
  • Simple suspension system, allowing for ease of movement cross-country with low ground pressure and allowing the vehicle to operate on wheels or on tracks equally, including the braking system.
  • Suspension units mounted or unmounted by means of the vehicle’s own power.
  • Simple driving mechanism.
  • Easy access.
  • All-round visibility.
  • A crew compartment distinct from the main gun and engine provided with its own ventilation.
  • Easy maintenance with a simple and reliable design.
  • Width of 3,150 mm.
  • Railways loading width.
  • Height “below that of a normal man” – 1,700 mm.
  • 700 – 800 hp engine.
  • 28 – 32 hp/ton. (28.4 – 32.5 hp/tonne)
  • 2 speed gearbox.
  • Wheel speeds of 80 km/h.
  • 65 km/h on tracks.

“There is no Tank either projected or existing which has only a few of the features of the ‘Straussler’ let alone all the large numbers of highly desirable properties which are assembled in a single device. There is nothing in any of the design features which are mechanically, technically, or operational of doubtful or of difficult nature and which cannot be designed, and manufactured by any competent organisation to produce a highly successful tank”

Nicholas Straussler

Layout

The whole tank was to be divided into three basic compartments. The front compartment housing the crew, behind this was the ammunition compartment, and at the rear, the engine compartment and fuel.

The outline for Straussler’s MBT shows a compact design with the crew area at the front. The weapon system is mounted in the center and the engine compartment at the rear.
Source: The Tank Museum Bovington, modified by the author

The tank was to be of a very low profile, with the gun projecting directly out of the front of the well sloped glacis and with a flat roof to a slowly sloping back. On each side of the vehicle would be two pairs of track or drive units, consisting of four double rubber-tired road wheels on a common frame able to rotate around a central pivot and around which was a track. At the rear of the tank would be a large and permanently affixed electrically-driven and steerable propeller system to provide propulsion in the water for the tank when floating. To aid in crossing a water obstacle, the tank would also have a large fabric screen that could be installed and easily erected. When not in use, this was to be held in a “perimental trough” (a recess running around the outside of the tank) and sealed with a rubber gasket.

Each track unit was designed to be fitted with a pair of large cantilevered spring leaf units, providing cushioning on the move. Braking was to be provided within the unit as well, in the form of 8 large disc brakes, constituting a pair per track unit. Further, because of the electrical drive system, electrical braking could be employed as well, providing an easy and simple method to control the speed of the tank. The 600 mm wide track itself was not particularly important to Straussler, although he did suggest the use of a “spring leaf” type of track, as it was cheap and light and could resist the sort of sideways forces imparted on a track during turning using its flexibility.

The middle compartment, designed to house the ammunition, had within it a cage which was rigidly attached to the breech of the gun, which projected through the front of the tank, through the crew space, and into this section. Ammunition would be loaded through the roof via a large trap-door style hatch into the middle compartment. Likewise, in order to refuel or access the powerplant, another hatch was on top of the hull over the rear section as well.

Date

Sadly, there is no date on Straussler’s design for this low profile main battle tank. The design can, however, be roughly dated by some of the technology within it. For example, the ‘perimental trough’ mentioned by Straussler is similar in description and purpose to a patent design granted to Straussler in 1947. That design was for a collapsible screen, as before, for imparting buoyancy on an armored vehicle. However, this was to be fitted into an armored box around the vehicle to prevent damage, instead it would be a permanent ‘trough’ into which such a screen could go on a purpose-designed vehicle.

An armored protective enclosure for an integrated collapsible waterproof screen allows an armored vehicle to carry a permanently fitted screen protected from damage.
Source: British Patent GB623427 of 1947.

A second clue is the use of the folding propeller at the back of the tank. In March 1942, Straussler filed a patent in the United Kingdom for this design shown on a Valentine tank with a wading screen clearly in place. Although filed in 1942, this design was not granted a patent until 1945.

The folding rear propeller to move a floating tank in the water.
Source: US Patent: 2398057 of 1946 from British Patent GB487622.

A further clue is found in the name itself ‘Main Battle Tank’. The term itself originated after WW2 and was first used around 1957. These three clues combined would imply a date of design of not earlier than around 1957 and perhaps as late as 1965 or so.

Armor

Armored side skirts could be fitted to enhance the protection of the vehicle and especially to protect the drive units. However, no other mention of armor is included in his letter accompanying the design and the drawing itself shows no implicit thickness of armor either. Based solely on the drawing, it can only be inferred that protection was to be very light and this would be in keeping with a planned weight of just 25 tonnes. Given the low weight, a relatively low level of protection could be expected and the vehicle would have to rely for its primary protection on its low profile. At just 1.7 m high, allowing it to be easily concealed or camouflaged, the armor, or lack of it, would leave the vehicle highly vulnerable to even just cannon fire.

Crew

Just two men were supposed to operate this vehicle according to Straussler’s design, specifically a commander and a driver. Access for them was by means of a large hinged “trap-door” arrangement on the roof of the tank, with one for each man. Each man would sit in the forward section of the hull, on the right, sitting upright alongside each other. This meant only their compartment would need forced ventilation.

As well as telling the driver where to go and operating the radio to receive their own instructions, share combat information etc., the commander was also tasked with firing the primary armament. Aiming and loading were done automatically as the primary sight (a telescopic periscope) for the gun was placed on the roof between the driver and commander’s positions. The sight could be shared so that, in theory, both men would be able to aim the main gun.

Armament

The ‘ideal’ characteristics for a main battle tank, as outlined by Straussler, had to include the largest possible primary armament which could be carried. For this vehicle, Straussler proposed a 120 mm gun, although he does not mention if it were to be rifled or smoothbore. Considering a probable design date of the mid to late 1950s and his British experience, this would strongly suggest a rifled gun as a logical assumption.

Straussler had proposed that guns should be loaded, aimed, and fired automatically and that the tank should carry as many rounds as possible. However, his design principles included the smallest possible size characteristics as well, and the result was that just 31 shells could be carried inside in the “shellcage”. With a predicted firing rate of up to 12 rounds per minute (one every 5 seconds), this meant a continuous barrage of fire of just 2 ½ minutes if firing took place without a break. The automatic loading system was to be driven by an independent electrical motor moving new shells into the breech and the casing from spent shells out of the breech. As the gun was fixed in a side-mounted gimbal, it could move in both traverse and elevation, both of which were controlled via a hydraulic motor by the commander.

Front cross-section of the design, showing the angled position of the loading system and eccentrical position location of the main armament in the front left of the hull. The gimbal mount is to the side of the gun, shown without a blue outline.
Source: The Tank Museum, Bovington modified by the author
With the original drawing removed, the positioning of the loading system is even clearer.
Source: Author

Possibly, the most unusual part of the armament plan for the vehicle was the position of the main gun. The basic layout of the vehicle and the protrusion of the gun from the front implies a centrally ( or close to center) mounted gun, as this is commonly seen on numerous other vehicles of a roughly similar design, from the Jg.Pz. 38 t and Jagdpather, to the Swedish S-tank. However, this is not the case at all. Close examination of the drawings show that the gun was in fact offset to the front left, meaning that both of the crew were sequestered inside not only the front ½ of the vehicle, but also the front right of that third.

An advantage of this layout was that it obviated the problem of the mounting of the gun being too far back. As such, when the gun elevated, depressed or traversed, it would leave a large ‘track’ in the frontal armor which had to be empty to allow gun movement. Given the arrangements, this ‘hole’ in the front armor would not leave any weakness in protection for the crew, who would be separated by both a lateral and transverse bulkhead, meaning that all the barrel might need was some kind of flexible canvas shroud to prevent water ingress. The gun itself was rigidly fixed to the “shellcage” of 31 rounds and automatic loading mechanism. The drive motors were fixed at an angle, causing the shells to be carried at around 25º to 30º to the vertical in the center, directly behind the crew compartment. The drive motor was inside the right sponson. If the gun rotated or traversed, this angled arrangement would prevent fouling.

Primary armament for the design, loaded and mounted centrally, along with the optional rockets on the roof.
Source: The Tank Museum, Bovington modified by the author

As well as the 120 mm main gun, 4 machine guns were also to be carried, of either a ‘heavy’ (i.e. 0.50 caliber) or ‘light’ (i.e. 0.303” or 7.62 mm caliber) type. These machine guns would be placed in a pair of turrets, with one on each side of the front of the tank’s hull, mounted on top of the mudguards over the tracks. These turrets would be rotated, aimed, and fired remotely from inside the tank, although this would seriously occupy the crew inside, who already had plenty to do. Nonetheless, the position of these twin machine gun turrets would, in theory, allow for a level of protection across a wide arc on both sides as well as to the front, although how these were to be aimed was not explained by Straussler.

Engine, Steering, and Propulsion

The vehicle was to make use of a hybrid-type of drive system, whereby an engine drove an electrical generator which, in turn, drove electric motors to drive the tracks and provide the vehicle’s propulsion.

Straussler wanted a multifuel engine, i.e. one which could run on petrol or diesel or any available fuels. This type of engine could be the ‘normal’ kind of piston-driven engine or the Wankel type of engine as an alternative system. The Wankel type engine consists of a single triangular piston with curved faces with reciprocates within a roughly ‘8’-shaped cylinder. They are commonly known as rotary engines and have seen commercial use in some sports cars but were, and still are problematic for some issues like lubrication. The advantages, however, offered by a Wankel engine would have appealed to Struassler, not only because of the larger proportional size to weight and power output characteristics, but also because this type of engine produced a more uniform torque than a ‘normal’ type of piston engine as well as less vibration.

Nonetheless, this desire or at least the consideration of a Wankel type motor harkened back to Strausssler’s work decades earlier and his 1911 patent for an engine of exactly that type.

Straussler’s rotary engine design of 1911. Note that this image has been digitally cleaned.
Source: British Patent GB1611.

This engine would drive a single generator which would then drive the electrical motors. One motor was provided for each track. With four tracks, that meant four motors. In his design submission, Straussler does not expressly detail the use of the motors, but this sort of system would have allowed the driver to vary the electrical current being supplied to each track in order to provide turning forces as well as providing redundancy from damage. For example, even if one track unit on each side was damaged by enemy fire and the motors stopped working, as long as there was at least one operational motor and drive unit on each side, then not only could the vehicle still move under its own power, but it could also turn. With a fixed gun, not being able to turn meant not being able to fight, so providing this kind of redundancy with 4 tracks was a rational and logical step. What it also meant was that the vehicle would be able to neutrally steer around the center of the four units by powering one side one way and the other side the opposite direction.

Straussler’s MBT with engine in the rear compartment, large air intakes above and folding propeller system at the rear.
Source: The Tank Museum, Bovington, modified by the author

The system had other advantages in common with some other hybrid designs, namely in the layout of the vehicle. Lacking the need to have the engine and gearbox mechanically connected (as this system did not need a gearbox) to the final drives, it meant that it would create a more efficient internal volume unencumbered by rotating shafts and differentials, etc. Instead, the engine and generator could be simply connected by electrical cabling to the motors. Each motor would then drive one wheel within each track unit, so that, of the four double rubber-tired road wheels, the lead wheels on the front track units would be powered and so would the rearmost wheels on the rear track units.

Improved Mobility on Land and Water

The intention of Straussler was to have the tank as capable of moving on wheels as it was on tracks. This was not new, in the sense that the concept had been around for decades, most famously with wheel-cum-track machines, and the reason was exactly the same. Tracked vehicles tend to be better off-road, especially on a soft surface, as the tracks spread the load on the ground and gain more traction, whereas wheeled vehicles are better on hard surfaces, like roads. With less weight moving around, there was also less wear and tear.

In order to change between wheels and tracks, Straussler envisaged a hydraulic jacking system, whereby the center 2 pairs of rollers on each side could be lifted. By doing this, it would transfer the weight of the vehicle to be borne by the large driven rollers at opposite ends of each side. The tracks, once removed, could then be gathered up and stowed on the tank, as it would be driving on just the four driven rubber-tired road wheels.

When in the water, propulsion would be provided by both the tracks and by the electrically driven propeller at the back, which could be both steered as well as raised, so it did not foul with obstacles under the vehicle when not in use. When traveling in the water, the fabric screen would be erected from its collapsed position in the trough around the outside edge of the tank. The screen would neither make the tank taller than it had been beforehand, nor wider or longer. It would, in fact, only serve to displace enough water to provide the buoyancy the tank needed whilst floating in the water. The closest vehicle showing how this might have looked in real life if it had ever been made, is the Swedish S-tank.

Screen used on the S-tank followed Straussler’s basic floatation principle and method for tanks. Note how the design has to be modified to go around the barrel – something his MBT design circumvented by mounting the screen on the roof.
Source: Pinterest

Of note during the transit of the tank through water by this method is that Straussler envisaged that it could be used as a transporter too. Specifically, he stated that between 15 and 20 men could be accommodated on the roof, enough to form a small assault party to seize a structure or other without the need for boats.

This was not the only potential use for the roof space either. Quite why Struassler thought that adding a rocket launcher might add value to his design is unclear, although his inspiration perhaps might stem from something like the ‘Calliope’ system. He declined to outline what sort of rockets or other items might be mounted. It is possible, therefore, that he was thinking of this type of chassis for being the basis for vehicles like a bridge layer, but he declined to elaborate on the comment. Be it for rockets or men, the roof was available for transport, but hopefully not at the same time for safety reasons.

Suspension

The most complicated part of Struassler’s design was not the unusual gun mount, vehicle layout or even the roof-mounted screen and rockets. Instead, it was the suspension and this, perhaps more than anything else, is the primary defect of the design.

Nicholas Straussler was undoubtedly a talented engineer and had paid a lot of attention to vehicle suspension before WW2. In 1935, he filed a patent for a centrally pivoted system with separate sprung wheels as outriggers on each end and secondary sprung wheels underneath to provide tension and spread ground pressure.

Straussler’s patented suspension system from 1935. Note that this image has been digitally cleaned.
Source: British Patent GB453200
Straussler’s 1935 patent suspension shown on his 10-tonne V-4 design before WW2. The amount of movement from the front and rear wheels is readily apparent during this movement of the vehicle by a crane.
Source: Pinterest

The lineage of thought from this 1935 design to his MBT design is readily apparent with a close examination of the drawing provided. The same basic system was maintained, with a central pivot (dark blue) on a longitudinal frame (orange) and with a pair of large wheels (yellow) at each end of the beam. Around these wheels would go the track (green), but this design provided track tension and springing slightly differently. Instead of the coil springs as used in 1935, this design clearly made use of long leaf springs (light blue) linking the large wheels via their pivoting sub-frame (pink). With that long spring leaf above the central pivot, there was a single return roller (light orange) mounted centrally, directly above the pivot for the whole unit. Directly below this central pivot was another addition to his 1935 idea, and second tensioning wheel (light orange) and one which also served to provide track tension, as it was attached to another spring leaf (light blue) which was shorter than the top one but also attached to the sub frame for the main road wheels. In this way, whichever way the entire unit rotated during passage over the ground, this wheel would be pushed down against the track, providing tension and contact of the track with the ground. Likewise, when the hydraulic system was used to rotate the track units, it would be done to put one end of the unit in contact with the surface, presumably a road. With or without the track units fitted, this would serve to elevate the tank somewhat.

However, despite the seemingly advantageous nature of this suspension, Straussler chose not to patent it.

The complex suspension and track unit from Struassler.
Source: The Tank Museum, Bovington, modified by the author
In ‘wheel-mode’ for road-marching, the track units hydraulically rotated with or without tracks. The vehicle would be elevated by this process, as identified by the change in ground level shown in by the red arrows.
Source: The Tank Museum, Bovington, modified by the author.

Conclusion

This vehicle was far from Straussler’s last design for anything, let alone military items. By the late 1950s, Straussler had retired from running a business but not from inventions. Living in Geneva, Switzerland, he continued to produce designs including a folding boat and a folding motorized tricycle, amongst other things. He returned to England and died in London in 1966, aged 75, leaving a long history of inventions and his folding screen floatation system as his defining legacy.

The Straussler MBT, however, was not one of them. The design was not going to get any interest from the authorities who, at the time, would have been building more conventionally designed vehicles, such as the Chieftain. The concepts in inherent amphibious capacity were useful ones, but not essential and the light armor and unusual suspension were perhaps just a step too far for the authorities to engage with. Likewise, the roof-mounted rockets were an unnecessary addition and added nothing to the fightability of the design and in fact detracted somewhat from the otherwise clever idea to have the roof plate serve as a means of transport for troops over a water obstacle.

Perhaps the cleverest part of the design is the hardest to see in the side view – the loading system. The British were not advocates at the time of automatic loading systems, let alone one mounted in the manner Straussler designed, but the ability to mount the gun in this way would have provided the vehicle with the ability to deliver substantial firepower quickly against an opponent, creating the effect of more than one conventional tank for less than half the crew.

It is hard to assess Straussler’s design as being perhaps a step too far as an invention and this perhaps is reflected in the lack of a patent submission for what was a novel layout and could quite rightly have received legal protections. Straussler was certainly no stranger to the process and maybe it is the fact that he did not specifically try and protect this layout that indicates that even he felt it had serious limitations too. The design today is in the files in the archive of The Tank Museum, Bovington, a mostly forgotten idea from one of the foremost engineering freethinkers of his generation.

Straussler Main Battle Tank. Illustrations by the Glorious Pavel Carpaticus funded by our Patreon Campaign.

Straussler Main Battle Tank specifications

Dimensions (L-L-W-H) ~4.50 (hull), ~6.80 (over gun), 3.15, 1.70 m
Weight 25 tons
Crew 2 (driver, commander/ gunner)
Engine 700 – 800 hp multifuel or Wankel type with electric drive. Propellor for propulsion in the water.
Speed 65 km/h (on land using tracks), 80 km/h (on land using wheels)
Armament Fully automatic 120 mm gun with 31 rounds
4 machine guns in a pair of remotely operated turrets

Sources

British Patent GB1622, Rotary Internal Combustion Engine, filed 21st January 1911, granted 21st September 1911
British Patent GB453200, Improvements in or relating to wheel suspensions for endless track vehicles, field 4th March 1935, granted 4th September 1936
British Patent GB623427, Improvements in buoyancy imparting means for vehicles, filed 10th December 1946, granted 17th May 1949
England and Wales Marriage Registration Index, 1837-2005, Page 746, Volume 1A.
England and Wales Marriage Registration Index, 1837-2005, Page 801, Volume 1A.
England and Wales Death Registration Index 1837-2007, Page 268, Volume 17.
England and Wales Death Registration Index 1837-2007, Page 701, Volume 5C.
England and Wales Birth Registration Index, 1837-2008, Page 530, Volume 1A.
Fletcher, D. (2020). Strausslers and Alvis. https://www.keymilitary.com/article/strausslers-and-alvis

Categories
WW2 British Prototypes

TOG Citadel

United Kingdom (1939) Heavy Tank – concept only

Background

The battlefields of the Western Front during WW1 were characterized by thick belts of barbed wire covered by machine-gun fire often from concrete bunkers, creating an area which was all but impassable to infantry. The ground, shattered by years of war and millions of rounds of artillery fire, was often a quagmire of mud into which men, beasts, and machines would drown. Even if they managed to cross all of that, they would be faced with having to cross enemy trenches, anti-tank ditches, minefields, and other obstacles.

The British tanks of WW1 were specifically designed to overcome much of these problems, adopting a characteristic quasi-rhomboidal shape in which the tracks would run over the top of the hull, producing a high leading point for the track and carefully shaped to maximize the ability to both climb a step and cross ditches.

The early designs were relatively crude affairs, with inadequate armor, quickly falling prey to German anti-tank rifles and slow enough to be hit by enemy artillery. As the war progressed, the British progressively improved the armor and layout to the pinnacle of the whole design evolution, in the form of the Anglo-American Mk. VIII heavy tank. It had improved armor, improved mobility, in a larger tank with more firepower, and still retained the ability to extract itself from the terrible ground conditions. However, that tank did not get the opportunity to show its true power during the war and the mass production of it, which was being put in place, was canceled with the end of the war. Nonetheless, the principles had been established and if only thinking in WW1 terms, then this layout of the tank was clearly going to be ideal.

In 1939, many people could see the clouds of war gathering over Europe as an expansionist Nazi Germany under Adolf Hitler became more and more assertive, dominant, and militaristic. With the 1938 invasion of Czechoslovakia by Germany, any doubts about the future aspirations of Hitler to become the preeminent military power in Europe were over. Despite the appeasement of men such as the British Prime Minister, Neville Chamberlain, Germany was not going to cease in its growth and there was little time to prepare for a new major land war.

Thus, on the eve of war, and apparently with little comprehension that the nature of this forthcoming conflict was going to be different from those conditions experienced 20 years prior, the Army was in a rush to find a heavy tank. They simply resorted to exactly what they knew had worked before, a Mk. VIII shaped vehicle, albeit with more armor and firepower than before and the additional task of smashing reinforced bunkers.

It is not without a substantial degree of irony that the man substantially responsible for the Mk. VIII design, Sir Albert Stern, had, unlike the Army, moved on in thought. Along with his colleagues on the not yet named design committee, he was proposing a much more modern design in the form of the 300G. That tank featured a high leading track to help climb, a longer hull to help cross obstacles, and firepower concentrated in the turret to better deliver its firepower.

The Anglo-American Mk.VIII tank. Source: Beamish Collection

Origins

Lt. Col. Sir Albert Stern, a man who was very much ‘made’ by his experiences in helping to shape armored warfare in WW1, was in a powerful position, with a title, wealth, experience, and contacts in government. He also foresaw what he thought was to come and, in June 1939, was asked to visit the Minister of Supply, Mr. Leslie Burgin, to discuss the issue of heavy tanks.

The outlook was dire. British tank development had, since the end of WW1, stood almost stationary. There were few tanks, and what there was a mixed bag of various types and quality, with the best armored of the bunch being the A.11 and A.12 Matildas. Both carried substantial armor for the time, 60 mm or more, enough to protect from most infantry weapons available short of artillery, yet both were under-armed and not long enough to perform the sort of assault role envisaged by some British military planners.

Despite the protestations of men such as General Sir Maurice Taylor, Senior Military Advisor to the Ministry of Supply, who was dead-set against heavy tanks, Stern had gathered supporters in the form of men such as Sir Maurice Grove Taylor and Major General Alexander Elliot Davidson, Director of Mechanisation at the Ministry of Supply, to his side.

If there was to be a new and heavy tank, these men decided it should be along the lines of what was already proven and with which they were familiar. Given the parlous state of interwar British tank design and the utter lack of a viable alternative, the outcome was as obvious as it was inevitable, the new heavy tank should be along the lines of the Mk.VIII tank of WW1. Whilst Stern and his team gathered together their expertise and came up with their idea in the form of 300G, the Army would busy itself with its own ideas and generate a list of specifications identified as RBM-17. Then, they made their own outline of a tank to meet their own specifications – the Citadel.

RBM-17

With the 300G in hand, Sir Albert Stern had an outline for what he and the members of his as yet unofficial committee felt would meet the sort of need they saw coming. This was not a full-scale reversion to the conditions of WW1, but an improved vehicle with more trench and obstacle crossing ability than existed before.

The philosophy of a new special tank was therefore already tacitly in place and set roughly even before war was declared on 3rd September. At that point, Britain was suddenly at war with a major and aggressive European power and had no heavy tanks at all. Although this initial idea that a new tank was needed was already in place, it is inextricable that it still took until 29th September for the results to travel all the way from the General Staff to the Adelphi Hotel, where rooms had been prepared for Stern and his team to work.

On 28th September 1939, however, when the Army brought with them their list of requirements for a new tank, it immediately meant that the 300G design, on which the team had been working, was redundant. The Army was absolutely insistent that the vehicle had to have certain features, including the firepower concentrated in sponsons and a large gun in the front to smash bunkers, two features impossible to accommodate into 300G. Further, they wanted a fundamental shift in design from a turreted machine back to an ‘all-round’ track machine, as this would facilitate heavy unditching equipment.

Copy of R.B.M.-17, the original specifications for what the Army demanded from the nascent S.V.D.C.
Source: Author’s collection.

The specifications themselves clearly show exactly what the Army felt it needed in terms of a short-range special-purpose tank, but they also show the naivety on engineering matters and of tank design in general, especially as at one point, some felt this could be achieved for a vehicle under 40 tonnes in weight.

Criteria Set

Design

The tank to meet the requirements of RBM-17 was going to have to meet a set of criteria like no other tank had ever been asked to fulfill. This set, in September 1939, may well have seemed impossible to achieve to the General Staff. If one were to assume that they had deliberately set Sir Albert an impossible task to keep him busy and quiet, they were to find that even these extreme criteria were met and exceeded.

Requirement one, and the most important, was that it had to be able to cross a 16’ (4.9 m) wide trench and climb a parapet or other obstacle 7’ (2.1 m high). This was basically the widest anti-tank ditch and a high wall. Both of these obstacles were uncrossable by any British tank then in existence and the RBM-17 was to cross these without the aid of a fascine (a large bundle of sticks to fill in a ditch) or bridge.

Length Requirements

This first criterion, right from the start, guaranteed more than any other that the final size of the machine would have to be at least twice the length of the trench simply to avoid falling into it. A 16’ (4.9 m) wide trench, therefore, meant a tank 32’ (9.8 m) or so long. To climb a 7’ (2.1 m) step meant a very high track at the front in order to get purchase (grip) high on the wall or parapet. It is no surprise that these match the general ‘all-over’ track shape of the Mk. VIII tank.

Shape Requirements

The other reasons the RBM-17 was to follow the Mk.VIII’s shape were equally practical. The tank needed the maximum bearing surface on the ground, meaning the widest track possible, so it would not get stuck in soft ground. It also had to carry heavy unditching gear. In other words, it had to be able to get itself out of a hole or soft ground using a method like that used in WW1, a large spar of timber carried over the top of the tank, on which the tracks could get purchase to pull itself out. This ‘log extraction’ is still in use today and the carriage of an unditching beam or log is now most famously associated with Russian/Soviet tanks, which are often still seen with a log on the back. The method of use is identical in principle except that, in the RBM-17’s case, no crew would need to get out. In order for that spar to be carried over the tank by the tracks and underneath, it also determined that an ‘all-round’ track machine and one without a turret, which would get in the way of the spar, was needed.

Armor Requirements

The tank would have to be immune to both 37 mm and 47 mm anti-tank fire at 100 yards (91 m) and against the impact of a German 105 mm howitzer shell at normal impact. Given that the ‘rival’ A.20 was being considered around a 60 mm basis at this time due to a similar need to be immune to the 37 mm gun and yet could not meet the demand, the RBM-17 would have had to have not less than this thickness of armor at any point. More armor, of course, meant more weight.

The preeminent 37 mm anti-tank gun of the era was the German Pak 36, which could achieve around 64 mm of anti-armor performance at 100 m. For a 47 mm gun, weapons such as the French 47 mm SA 37 could deliver an anti-armor performance up to around 90 mm at just over 500 m and around 100 mm at 100 m.

A 105 mm shell, such as that from the German 10.5 cm leFH 18, was nearly 15 kg in weight with nearly 2 kg of explosives inside. Bearing in mind the often wafer-thin armor on the roof of tanks, being hit directly by such a shell would be devastating. Even a close ‘hit’ landing and bursting nearby was perfectly capable of crippling a vehicle, stripping off wheels or tracks or topping it over.

The Army was demanding immunity at 100 yards (just under 100 m), so clearly anything less than 80 mm of armor was going to be unacceptable, although the attention to protection from artillery would wane a little in emphasis as time went on.

Firepower Requirements

The gun was still not yet decided but had to be in the front and capable of defeating the heavy German bunkers (7’/2.1 m thick concrete) which were so worrisome to the General Staff. As such a gun would, by its very nature, be restricted to only a limited range of fire to the front, the tank would also need side armament to rake German positions as it passed them. Here, the General Staff wanted something simple, just a 2 pdr. and Besa machine gun combination in a sponson on each side. On top of this was to be a separate Besa pointing forwards and another to the rear. Eight smoke dischargers completed the required armament, as these would provide cover for the tank and infantry to follow.

All of this equipment and armament meant a crew complement of 7 to 8 men. The tank was to be powered by a diesel engine to reduce fire risk, fitted with a No.9 radio to speak with other tanks and troops, had to be able to go 50 miles (161 km) on its own and, on top of this, be able to be transportable by rail with little or no disassembly.

It must also be considered that Sir Albert and the soon-to-be-named ‘Old Gang’ clearly thought little of the ‘no turret’ and all-over track idea. Their first design was, in fact, far more similar in shape to the A.12 and A.20 than the Mk.VIII. When the requirements for the length of trench to be crossed were decided, the design grew longer, and when the turret was abandoned and all-round track selected by the General Staff, the Mk.VIII shape was inevitable. Those other TOG designs are known only by drawing number 300G in both a long and ‘compact’ form. Both were shelved in favor of the Mk.VIII approach, although the longer version would later be resurrected when a modicum of sanity returned to the General Staff.

In these early days, the selection of armament was a key consideration and a variety of armament and mounting options were considered across Sir Albert’s work and the A.20, including a 2 pdr./Besa 7.92 mm machine gun combination, as found in the turret of the A.12 Matilda, a 3” howitzer, a 3.7” howitzer, naval 6 pounder, and the French 75 mm gun, as used on the Char B1.

The 2 pdr./Besa option would only work if a turret was going to be selected for the tank, which meant a hull-mounted gun. With the 3” and 3.7” guns being low-velocity weapons, they were abandoned. This was because the work of Sir Albert had been given a very strict and very specific set of requirements, one of which would require a particularly powerful gun firing a high-velocity shell capable of breaching 7’ (2.1 m) of reinforced (ferro) concrete.

The requirements were specifically listed under the heading “Super-Heavy Tank (Land Battleship)” under the code ‘RBM-17’. The exact meaning of those code letters has never been adequately explained but, given that Sir Albert’s committee was already being labeled in a sort of British public-school humor kind of way as ‘The Old Gang’, it could be speculated that such a boyish kind of name was being thought of here for this ‘Really Big Machine’. The committee designing this vehicle would later (October 1939) receive a formal acknowledgment as the Special Vehicle Development Committee (S.V.D.C.), but they were equally happy using the ‘TOG’ term themselves as a badge of honor rather than as a mark of scorn, as has been happily assumed by some authors in the decades since the war.

The Citadel Design

Brigadier Kenchington from the War Office and Colonel Watson were the men who brought the RBM-17 specification ‘wish-list’ to the meeting with Sir Albert Stern. With them too was an interpretation of what this would look like for the committee to work on. It is not clear if the vehicle outline that they brought with them as a ‘Citadel’ tank was directly from these individual officers themselves or from the War Office or General Staff or a mix of the bunch, but the design was clear in realizing the needs of RBM-17.

The outline for the Citadel, labeled as ‘TOG-1’, dating somewhere between September and probably November 1939.
Source: The Tank Museum, Bovington

Layout

The presented vehicle was a long, low, lozenge-shaped tank, roughly along the lines of the Mk. VIII, but with a large field gun mounted in the front of the hull with heavy unditching gear. It was drawn showing large round, presumably cast sponsons for the 2 pdr. / coaxial machine gun combination. One important note on this design is the issue of crew access. No doors are shown and, in correspondence over the next month or so, the only comment on this topic was on the removal of side doors behind the sponsons. This too was presumably similar in intent to the Mk. VIII, although the shape or style of such a door is unlikely to have been the same given the heavy armor requirement.

Side access doors for the WW1 era Mk. VIII were thick enough to protect against small arms and even anti-tank rifle fire, but were nowhere near the armor required by RBM-17. Likewise, the idea of a door-mounted machine gun was never contemplated, as the side machine gun was to be coaxial with the sponson-mounted 2 pdr. Note the small rails for the unditching beam on the back do not extend forwards to the casemate.
Source: US National Archives

On top of the tank and projecting above the level of the tracks was a raised superstructure with a small cupola. This lookout allowed the commander to see where he was going and communicate to the driver in the front left. Whilst it may or may not have been rotatable, it was not an armed turret. The more notable issue on this raised section in the fighting chamber was that, just like the Mk. VIII, it would prevent the whole unditching beam over the top of the tank idea as well. Here, then, there seems to have been a disconnect in the minds of the military planners for the General Staff, who seemed to be confusing the earlier marks of British tanks, which used rails over a small raised structure for an unditching beam to travel over, with the rear-mounted beam on the Mk. VIII. Photographs of the Mk. VIII clearly show that the rails on its roof only extended over the rear section of the tail and thus that the beam would then not be able to be carried forward to help unditch the vehicle. The Mk. VIII therefore would only be able to deploy this beam backward to reverse out of a particularly boggy hole, whereas the early tanks, such as the Mk. IV, could deploy the beam forwards to get out of a hole forwards or in reverse.

Shown post-war on display, this vehicle clearly shows the issue of the top rails, whereby a beam or other equipment, such as a fascine could be dragged over the top without fouling on the casemate.
Source: Pinterest

Armor

No details on the armor for the Citadel idea were noted, other than the immunity requirement. Given that 37 mm and 47 mm anti-tank guns could respectively perforate between around 60 and 80 mm of armor at 100 yards (91 m), the requirements guaranteed armor not less than that already in use of the A.12 Matilda, with 3” (76 mm) of armor. Importantly, the immunity requirement did not specify that the armor had to be that thick per se, just that it needed to provide that level of protection. Whilst the vertical sides would need to be at least that thick, the front may not have needed to be, given the slope, but even so it would seem unlikely that the front, even sloped, would be thinner. The same is true of the sponsons, with their distinctive curved shape, projecting from the sides. Given the size of them, each would likely weigh roughly the same as the turret of the A.12 as well. It is not hard, therefore, to see why the desire to replace two of them with just one turret would finally win out later.

Armament

RBM-17 made it clear that the Army wanted a field gun in the front which could breach enemy heavy bunkers up to 7’ (2.1 m) thick and various options would be discussed with the S.V.D.C. as they tried to meet this demand. Of the options considered, there was little to choose from.

The biggest gun which could potentially be made to fit in the front was the venerable 60 pounder. The B.L. 60 pounder was over 30 years old and had seen extensive service in WW1, firing a 60 lb. (27 kg) shell containing 8 lbs. (3.6 kg) of high explosive at 650 m/s out to a range of 9 km. The gun itself was massive, employing a wheeled carriage and usually serviced by a crew of 10 men when used as a field gun. Even so, it produced a rate of fire of just 2 rounds per minute. The gun was also very long, with the barrel alone measuring nearly 5 m from breech to muzzle. This produced a problem for the front of the vehicle, as the barrel would potentially impale itself into an obstacle, such as the opposite face of a ditch when the vehicle was crossing it. Thus, the option of shortening the barrel was considered, even though this would reduce the muzzle velocity of the gun. However, as the long version firing HE could not defeat the 7’ (2.1 m) of concrete, the Army demanded that the gun would not be shortened.

Little discussion seems to have focussed on the two other huge problems of using such a gun in the front. Firstly, the fact that just one man was supposed to operate it and, no matter how much bully beef he might get, this would be an enormous task for one man who was also at some point supposed to use the front machine gun too. The second issue was how to mount such a heavy gun in the hull. Perhaps thankfully, this gun was discounted as a realistic option before any precious design resources were expended on trying to create a mounting that could take both the weight and the recoil.

British B.L. 60 pounder Mk. II in service in the 1930s with the British Army. A crew of 5 men can be seen operating this gun, with other men off-camera.
Source: wiki

The reality was that, in September 1939, there was no gun that could be mounted in the front which could achieve that 7’ (2.1 m) requirement. Whilst the demand for concrete destruction would be kept, it would end up as an ‘as much as possible’ requirement going forward through the end of 1939, rather than an absolute figure to be achieved.

Speed

The tank did not need to be fast in any way. There was simply no need. This vehicle would primarily be used for smashing enemy positions. Further, a slower vehicle emphasizing protection would resist the deleterious effect of enemy fire which it would attract, provide a more stable firing platform for firing back, and also clear a path for further tanks and troops to follow.

The low speed was also a reflection of reality. Whilst 5 mph (8 km/h) is certainly not by any means fast, it is surprisingly quick across the sort of terrible terrain which might be encountered in a Flanders-type shattered battlefield, with heavy mud and waterlogged ground. In fact, this speed would not only be faster than its forebears a generation earlier over such ground but also faster than any other tank in such conditions as well.

Crew

RBM-17 called for a commander, a driver, and a separate radio operator. Separating the radio operator from the commander, which was usually his dual job in a British tank, would at least take away one burden from him, but the job of commanding the vehicle was not going to be simplified much, as he would have to now control the crew operating the gun in the front hull and both sponsons. Two men, one for the 2 pdr. and one for the machine gun, would crew the sponsons on each side and just one man was supposed to operate the front hull gun on his own.

This herculean task for the front hull gunner/loader would certainly have been more than a little burdensome if a gun like the 60-pounder was adopted, having to haul the shells on his own, load them, aim the gun and fire, and then repeat. This would have been exhausting and slow work in the confines of the tank with all of the other activities going on, especially if it was moving at the time.

Power

The powerplant for this machine was not mentioned, described, or suggested. The fuel type was clearly spelled out as ‘diesel’. Although high speeds were not called for in the design brief, there was still going to be an issue over the availability of high-power diesel engines and how to transmit that power from the engine/s to the tracks. An eventual solution would be found to meet the need for power from a diesel thanks to Harry Ricardo, the engine designer on the S.V.D.C.

However, in September 1939, it was not that clear cut and engine options were severely limited by not only the power output needed, but also by the fuel type, as few diesel engines were available which could deliver the power of more than 500 hp which would be required and options to be considered included more than one engine, various domestic and foreign engines, and different types of transmissions to maintain efficiency.

An approximation of the Citadel tank of September 1939 modeled from the eventual hull of TOG-1 with the rounded sponsons and shown here with the long-barrelled 60-pdr. gun projecting from the front.
Source: Author
An approximation of the Citadel tank of September 1939 modeled from the eventual hull of TOG-1 with the rounded sponsons and shown here with the shortened 60-pdr. gun projecting from the front.
Source: Author

Conclusion

The Army’s design for the Citadel was odd, harkening back to the worst days of the slaughter of WW1 and no doubt that conflict served up generous helpings of concerns of a repeat of it. Seemingly in haste, the Army had leapt on Stern’s idea that, quite rightly, the Army needed a new special tank to prevent that type of warfare from taking place. Equally, the high command appeared to be panicking. This rush to get ‘something’ is seemingly made clear by the disconnect over the general outline of a tank. The Army were insistent on a turretless tank, so as not to interfere with heavy unditching gear, yet this very requirement was gone even by the end of WW1 with the change from all-over rails to just rails at the back for the unditching beam. Indeed, it is unclear how the High Command seemingly lacked knowledge on the topic, as even in WW1, vehicles had gone away from this type of complete top rail, as seen on the Mk. VIII, Medium Mk. B Whippet, and Medium Mk. C Hornet. Why the Army seemed so insistent on no turret because it would interfere with this equipment makes no sense when a turret would make no more interference than the raised casemate. This, perhaps more than anything else, shows that the Army was rushing to get ‘something’ to fill a need rather than relying on experts like Stern’s committee to develop a new vehicle.

The proposed design had too many crewmen and was too hard to control. Reducing the crew meant fewer men would be needed, more space in the fighting chamber for air to circulate, more space to move around, and more space for storage of ammunition, etcetera. Fewer men could be achieved by the adoption of a turret which would concentrate the firepower equivalent to both sponsons in one place as, afterall, both sponsons could not fire on the same target at the same time in anything other than the very limited circumstances of the target being directly ahead of the tank a distance away.

Removing sponsons would not only eliminate the need for so many crew and improve the interior volume, but would also remove two other significant burdens. One was the problem of transshipment, as no sponsons, or just small machine gun sponsons were far easier to move, fold in, or remove than these huge sponsons demanded. Secondly, their removal would save a lot of unnecessary weight from men, armor, and guns.

Adopting a turret would become the logical conclusion as the S.V.D.C. got to work on the Army’s idea, as saving crew and weight, and improving the distribution of firepower issues altered the general shape of the eventual vehicle into the ‘TOG-1’. Even with a turret, it was not the vehicle that the S.V.D.C. would design to meet the needs of RMB-17. That vehicle would have to wait, as the committee formed under Stern got to work in October 1939.

The size of the machine was inevitably going to be big given the size of the trench that needed to be crossed and the same is true of the front contact, with a 7’ step requiring a high front end. The Army’s demand for an all-road track likewise demanded a machine shaped like the Mk. VIII.

What the struggle to find a suitable powerplant would show was just how unrealistic RBM-17 was as a demand. At one point, the Army’s goal was to make this monster of a tank under 40 tonnes, a completely ludicrous idea that any engineer or designer would have laughed at when the Army was literally demanding a gallon in a pint pot.

In the end, the Army would not be able to get what they wanted. The requirements, although they could be met, could also be improved upon. The S.V.D.C. under Sir Albert Stern would develop a vehicle along the lines wanted by the Army and eventually persuade them of the value of a turret over large sponsons, and that vehicle would be TOG-1. The performance of TOG-1 would also exceed the Army’s requirements for mobility and obstacle crossing and, in fact, exceed their extreme requirements for a vehicle for all but the ability to smash a 7’ thick reinforced concrete structure. That requirement would be practically impossible at the time anyway, regardless of what design they might have come up with, and would remain out of reach for a couple of years until the advent of the 17 pdr.

The Citadel, however, was a starting point for the SVDC, as limited and relatively crude as it was. With a team of experts and mandate for work, the restrictions of RBM-17 would fade a little as the war developed, but the special tank concept would continue and the Citadel became just a footnote in the history of the committee.

Side view of the TOG Citadel with the shortened 60 pounder gun. Illustration by Ed Jackson, the winner of our illustration competition.

Specifications TOG Citadel

Dimensions >32’ (9.75 m) long
Weight >40 tons
Crew 7 – 8 (commander, driver, wireless operator, 4 – 5 gunners)
Speed (road) 5 mph required (min. off road of very bad ground)
Range 50 miles (80 km)
Fuel Diesel
Primary Armament heavy field gun such as 60 pdr. or shortened 60 pdr.
Sponson Armament 2 pounder gun and 7.92 mm BESA MG on each side
Other Armament front and rear 7.92 mm BESA MGs
Armor Sufficient to protect against 37 and 47 mm anti-tank guns and 105 mm howitzer
For information about abbreviations check the Lexical Index

Sources

Hills, A. (2017). The Tanks of TOG. FWD Publishing, USA.

Categories
WW1 US Armor

Ford 3-ton Special Tractor M.1918 (Ford 3-ton)

USA ww1 USA (1918) Light Tank – 15 built

The First World War broke out in 1914, dragging into the maelstrom the major powers of Europe and beyond. As early as 1915, faced with the carnage wrought by the industrialization of war exemplified by the use of the machine gun, armed men were being killed at enormous rates on the battlefields of Europe. Different armies took different approaches to resolve the problem. For Britain and France, this took the shape of armored machines to convey troops across enemy barbed wire or just to clear a path. This resulted in tanks like the British Mk. I and French Schneider. The Germans and Italians were not far behind with their own programs, yet the United States, having isolated itself from the fighting in WW1, had no development program of its own and, despite seeing these allied machines go into battle, took relatively little notice of this new epoch in warfare.

When the United States did finally enter the war in April 1917, it did so with a naive and mostly untested military, more resembling European armies of 1914 than the battle-tested forces and tactics of 1917. The one thing it certainly lacked was the tank and, for a while, would have to try and get hold of some wherever it could. These first vehicles initially came from the French, in the form of their own FTs and the license-produced version, the M1917, and later with the British, as a joint program to develop the Mk. VIII heavy tank.

The final scale of the tanks produced in the United States, from the tiny and mostly useless Ford 3-ton on the left to the Renault FT/M.1917 in the center, and Mk. VIII heavy tank (right).

In the middle of this was the automotive manufacturer, the Ford Motor Company. Ford would clearly take a hefty amount of inspiration from the Renault FT tank and put it into a diminutive package weighing just 3 tons. This was the Ford 3-ton, America’s first true independently-designed tank.

The concept of such a small, lightly armored, and lightly armed tank is questionable, especially with the benefit of hindsight over a century later. In 1917, however, there was little to go on from a design point of view for inspiration and even less in the form of combat experience on which to base a decision. The British had employed quasi-rhomboidal tanks at the end of 1916 but the deployment, whilst successful in the context of previous infantry attacks, was still not the giant breakthrough as hoped for.

Those British tanks were large, and slow, weighed over 30 tons carrying bulletproof armor and carrying either machine guns or 6 pounder guns or both, they were at least well-armed. The French had pursued their own tank program and would deliver an equally slow but less well-armed Schneider CA. They would, on the other hand, produce a far more effective tank in the form of the Renault FT. The trend, therefore, suggested smaller vehicles were more effective, which may also be cheaper and lighter. A lighter tank was easier to move both by train and on a road where the Renault FT was even moveable on the back of a truck.

The Ford Motor Company, it seemed, wanted to emulate the small tank concept. Small and light meant the advantages of both strategic and tactical movement but also faster and easier production. For a major car manufacturer, the opportunities of mass production of a tank made from straightforward components – like those already known to be successful on the Renault FT – was clearly the inspiration.

The Ford 3-ton prototype was built as an artillery tractor, with significant work being done on the suspension of the vehicle. However, the US Army wanted a tank to ship to the battlefields of Europe, so a light machine-gun was added, along with some other minor changes, and 15,000 Ford 3-ton tanks were ordered.

The Design

Despite witnessing the employment of the first tanks by the British and then the French, work in the US on their own tank had started late and progressed slowly. Even if a design was going to be more easily producible, it would take some time to overcome the significant lead in tank building by the British and French. The Americans had wasted valuable time converting the French FT design from metric to imperial measurements to suit American manufacturing, delaying the introduction of the tank. By March-April 1918, little progress on any tanks had been made, although the first prototypes of the 3-ton were at least finally ready.

The French Renault FT light tank. Armed with either a single machine gun or 37 mm cannon, the tank was characterized by the large front wheel raised off the ground, a horizontal beam with the road wheels and a low rear idler with the track’s return run carried in a curve across the top. At the rear is a large skid to assist in crossing a gap.
Source: Craig Moore

The first prototype vehicle was little more than a lightly armored and unarmed steel box for towing guns or equipment around a battlefield. With only one man needed to command and steer the vehicle, the layout left space for a second man in the front left of the vehicle. The development of a ‘tank’ version of the tractor was an obvious step forward, achieved by sticking a weapon in the front left for this extra man to operate, with the only cost being that access would go from two hatches to just the single hatch in front of the driver and the second hatch repositioned on top of the projection in the front housing the machine gun. That would not be the only change from the prototype tractor to a production tank though. The suspension would also be revised to progressively improve its performance. Even so, this first American-designed tank was never going to see combat and was clearly inadequate compared to the far more capable Renault FT or the American version which, at the time, still had not been finished.

Photographed at the Ford plant, Detroit, Michigan in April 1918, the simplicity of the design of the tractor is readily apparent, with the side armor consisting of just two plates. Note that the front idler is made from individual steel stays riveted together and that the common axle they share is exposed across the front exterior of the tank. The suspension would be improved for the tank version but the basic shape and layout would be retained.
Source: US National Archives Reference 165WW-313-A-64

The shape of the Renault FT has, since the end of WW1, become iconic with its egg-shaped track run, with the sprocket at the narrow end of the ‘egg’ at the back, and large idler wheel at the big end at the front. The large front wheel assisted with climbing obstacles and the top of the track run was held in place by means of springs, providing track tension for the whole system. The prototype Ford 3-ton had adopted this basic shape and even the French style track at the prototyping stage. This would be retained, albeit with some modification as the vehicle entered production.

Arrangement for the tank was also similar to the French Renault FT, with the engine to the rear, although with no separating bulkhead, under an angled roof. Ahead of this was the compartment for the crew. The most notable difference between the two ideas (this 3-ton and the Renault FT) was obviously the lack of a turret. The first prototype would also clearly be more ‘tractor’ than ‘tank’, as the front was devoid of any armament, with a flat front face angled slightly backward. The second version, the ‘tank’, would not have a turret but it would at least allow the US to have some armored ability to bring firepower to battle.

Nonetheless, the outcome would still end up inferior to the French tank. Still, something was better than the nothing the US Army had at the time.

A finished prototype Ford 3-ton fitted with an unknown machine gun. Note the relatively crude cylindrical commander’s cupola and that the jockey wheel at the front is ‘solid’ compared to the previous ‘open’ web style.
Source: US National Archives reference 165-WW313-A-67
First pattern of Ford 3-ton with the crude drum-shaped cupola during trials.
Source: US National Archives reference 165-WW313-A-65
First pattern of the Ford 3-ton climbing a slope.
Source: US National Archives reference 165-WW313-A-66

Armor

Despite being smaller than the Renault FT, the vehicle carried armor just ½” (12.7 mm) thick at best and down to ¼” (6.35 mm) for the floor, just like the prototype.

With just 12.7 mm, it was very much vulnerable not only to anti-tank rifles but also potentially to concentrated machine-gun fire and the ‘reversed’ German rifle bullet. On top of that, if the armor was perforated and a fire ensued with the fuel, the Renault, with its engine separated by a bulkhead from the crew, allowed some chance of escape, especially as each crewman had his own hatch. The Ford 3-ton tank, for whatever other failings it had, still provided one hatch per man to escape, although, with no divider between the engine and crew, a catastrophic and fatal fire was a very real hazard.

Automotive

Powered by a pair of Ford 4-cylinder petrol engines taken from the Model T car, spares would not be an issue. The engine was in mass production already so was known as a reliable and robust unit, albeit an anemic one. The engine itself had first been introduced in October 1908 – it would stay in production until May 1927.

Each engine consisted of a cast-iron block with 4 cylinders and 2 side valves per cylinder, reliant upon splash lubrication of the oil and cooled by water. With a capacity of 2.9 liters, each one could deliver between 20 and 22 bhp at 1,600 rpm and 112.5 Nm (83 ft/lb.) of torque.

The 2.9 litre Ford Model T petrol engine, as fitted to the motor car, showing the positions of various component parts. Source: Model T info.net

The solution to improve the power was not to develop a new and improved version of the engine, but to stick to what was known and to simply pair two of these engines as the powerplant. This gave a combined output of 34 hp at 1,700 rpm. At 3 tons, this would mean a calculated theoretical power to weight ratio of around 11 hp/ton, although the actually measured ratio was just 9.4 hp/ton due to the inherent efficiency losses in the transmission system. Nonetheless, the power plant selection, on the face of it, made a lot of sense. However, the selection of two engines made a combined single power output difficult and the outcome was that each engine would have to drive half the vehicle.

Arranged alongside each other, these engines had their own Ford planetary transmission and final drive, with each one only powering one side of the tank. Thus, the left engine drove the left track and vice versa. This was not the first vehicle to use this idea. The engines were started electrically.

The basic arrangement of the British Medium Mark A Whippet, which used a pair of Tylor engines side by side, with each driving the track on that side of the tank.
Source: Graphic modified by the author from an original drawing.

Combined together like this, the Ford 3-ton could achieve a top speed of around 8 mph (13 km/h) on a good hard surface. This was plenty for WW1, when the primary role for tanks was one of infantry support. For reference, the French Renault FT could achieve just 7 km/h and the British Whippet 13 km/h.

The transmission provided for 2 forward and a single reverse gear, meaning the vehicle could have one engine put into reverse and the other forward to spin on the spot, although the official technique was to put one into neutral and the other into drive. The commander drove the vehicle using hand levers, for which one lever controlled each transmission. Two brake pedals, one for each track (left foot pedal braking the left track, and right foot pedal braking the right track) added to the steering system, so that a sharp turn was to be done by braking one side and putting that side into neutral whilst the other side went ‘forwards’ or into reverse, turning the tank.

A fuel tank containing 17 US gallons (64.4 liters) of petrol provided an operational range of just 34 miles (55 km), assuming it was operating on flat and firm ground running at a fuel consumption of 2 miles per gallon (0.85 km per liter). Air for the engine for cooling and combustion purposes was drawn in through a raised rib on the rear spine of the tank and the exhaust was vented out of the back, with one exhaust pipe on each side at the rear.

The power plant for the Ford 3-ton, a pair of Model T Ford 34 hp petrol engines, each driving its own side of the tank.
Source: US National Archives reference 165-WW303-116
The complete power plant for the Ford 3-ton, combining a pair of engines, two transmissions, two final drives, and the radiator and fan installed.
Source: US National Archives.

Crew

A crew of two men was to be provided for the tank version of the vehicle. The commander, situated on the right, could merely observe to the front, commanding the man to his left, assuming he could hear him over the din of two engines directly behind them in a steel box.

View inside a Ford 3-ton tank from the front looking backwards, The engines have not yet been fitted and the incredibly tight space inside is readily apparent already. Note the two oval view holes provided in the back of the crew compartment and the lack of a divider between the crew space and the engine bay.
Source: US National Archives Reference: 165-WW-313-A-61

The commander’s only other job was to drive the vehicle. No armament was provided for the commander to use and no wireless either. The gunner, situated on the front left, had to operate the primary (and only) firepower for the tank.

Armament

The primary armament for the Ford 3-ton was a single 0.30 caliber machine gun in the front left of the hull. The original machine gun which had been selected was the 0.30 caliber M.1917 Marlin (a stripped-down version of the M.1895 Marlin), a rather ancient and fairly obsolete weapon that found use in both aircraft and tanks for the USA. This gun was soon switched to the 0.30 caliber Browning machine gun instead. Emulating the French Renault FT a little more was the consideration of making a version with a 37 mm gun as well.

0.30 caliber Marlin machine gun fitted into a mount identical to that used on the Ford 3-ton, prepared here for fitting to the US version of the French Renault FT, the M.1917. Note the aluminum cooling fins on the barrel and bag to catch the spare brass.
Source: Hunnicutt
A Marlin 0.30 caliber M.1917 tank machine gun preserved at the Pennsylvania Military Museum.
Source: WilliamMaloney.com
Interior view of a 37 mm gun, as postulated for the Ford 3-ton, shown here in the housing used in the US version of the French Renault FT, the M.1917. Note how compact this gun is.
Source: Hunnicutt
Ford 3-ton mounting the 0.30 caliber Marlin machine gun.
Source: Pinterest
Ford 3-ton mounting a 0.30 caliber Browning.
Source: US National Archives Reference 165-WW-313-A-4

Movement for the machine gun within its mount was limited. It had a traverse of just 10 degrees left or right, elevated to up to 42 degrees, and depressed to -5 degrees.

Suspension

The Ford 3-ton was to go through some substantial revision work on its suspension. The initial attempts on the prototype had resulted in a track emulating the French Renault FT, with a raised front idler and a rear-drive sprocket both raised off the ground. The prototype had also opted for 5 identical steel wheels fixed to a framework on the side of the hull, with a sixth wheel above wheel number 4 to help keep the track tight. With no springing suspension and not even rubber tires on the wheels, the vehicle had no suspension at all.

The first simple step was to improve track tension by replacing that single return roller with a pair of smaller wheels connected to an inverted leaf spring connected to the same mounting point. The spring tension would thus ensure that, even as the track wore and became loose, the track tension could be maintained.

Side view of a newly completed American-built version of the Renault FT, known as the M.1917, coming out of Van Dorn Iron Works in 1919.
Source: US National Archives Reference 165WW-313-A

The track links were simple steel plates with a built-in spud protruding from one edge, just like the Renault FT. Measuring just 7 inches (178 mm) wide, the links were connected using a single steel pin. There were 40 track links on each side and a ground contact length of 56 inches (1.42 m per side), for a ground pressure of 9.2 pounds sq. in. (0.063 MPa). To complement this simple and effective track system, along with the improvement to the front idler and more robust rear drive sprocket, was a suspension system for the road wheels as well. Gone were the 5 rigidly fixed wheels and, instead, a new system formed from two triple-wheel bogies was added. Each bogie was attached to one end of a large leaf spring anchored centrally. This system allowed for a small degree of vertical movement for the wheels, improving both traction and ride for the crew. An angular cover plate was still used over these wheels, but did not serve to support the wheels. It was meant just to keep the bogies as clear of mud and debris falling from the track return run above them as possible.

Side view of the Ford 3-ton tank, providing a clear view of the sprung double roller suspension unit and tail skids used to help cross a trench.
Source: US National Archives Reference 165WW-313-A-13
Rear ¾ view of the Ford 3-ton tank, providing a clear view of the double tail skid. The circular marks behind the tank appear to indicate it has been showing off its turning ability.
Source: US National Archives Reference 165WW313-A-12
Rearview of the Ford 3-ton, providing an excellent study of the rear end, with the tail skids and exhausts. Note that the commander’s cupola has vision slits facing backward, as well as the two circular vision holes in the rear of the crew compartment. Quite how the crew were meant to contort themselves to use these is unknown. Note the simple towing eye at the bottom, between the skids.
Source: US National Archives

Utility

There were very clearly two simple and distinct roles for the Ford 3-ton. The first, as exemplified by the version which was unarmed (the ‘3-ton tractor’), was a mobile lightly armored artillery tractor for towing field guns, machine guns, equipment, and men around a battlefield.

The second was for infantry support, using a front-mounted machine gun, although this armed version would also be able to tow a field gun just as well as the unarmed version could. As the hulls were the same, tracks were the same and power plant and transmission were all the same, simply put, the tank could do everything a tractor version could, making the tractor version redundant.

Production

Being late to the party did not mean that the US Army had small plans for tanks. In fact, some 500 of these tiny tanks were to be delivered by January 1919, from an initial order of 15,000 vehicles. However, with the signing of the Armistice in November 1918, it was clear that the war would soon be over and that the fighting phase had ended. Thus, there would be no need for huge herds of these tanks for the Army, which might get a chance to spend some time developing something a little better for the future.

Ford 3-ton being examined in France by French and US officers. This vehicle appears to have the number 89863 stenciled on the engine bay door which is open.
Source: Pinterest
A film still of footage of the Ford 3-ton during testing in France. This particular vehicle has the number US 9306 stenciled on the hatch for the commander/driver. Note the small steel rod holding up the commander’s cupola in the open position, although the small opening was likely not large enough to use for access.
Source: Pinterest

The result was that all orders were canceled, just 15 vehicles being built. The US Army Ordnance Department, in a measure of its frugality, admired this vehicle for its simple nature, which would make mass production simple (an estimate of 100 vehicles could be churned out every day by Ford if so required by Spring 1919) and low unit cost of just US$4,000 (US$63,200 in 2021 dollars).

Shipped to France by the US Army, the goal was to try and get these vehicles into combat, but they did not arrive until November 1918, whereupon the Tank Corps took the view of the French that it was not suitable for combat but might have some use as a light artillery tractor.

The French, who examined it, did not like the vehicle. They already had plenty of tank experience and saw no utility in this tank at all. Although it has been suggested that the US was trying to persuade the French to buy these tanks, that seems highly unlikely or at least just woefully optimistic given the Renault FT was a better tank or tractor in all regards.

Front ¾ view of the final model of the Ford 3-ton. The only armament is mounted low and well forwards, but would be awkward at best to operate for the man lying behind it.
Source: US National Archives
The poor visibility for such a low vehicle, dependent on just a few slits in the commander’s cupola and a simple hole for the gunner, left a lot to be desired. With thin armor, the vehicle was severely limited for any combat use.
Source: US National Archives
Elevation for the Ford 3-ton from a French report on the vehicle dated 4th October 1918. The spring suspension system is clearly shown.
Plan view of the Ford 3-ton from a French report dated 4th October 1918.

Conclusion

The Renault FT and the US version, when it would finally be ready, were both substantially superior to the Ford 3-ton in almost every regard. More armor (22 mm vs 12.7 mm), wider tracks for improved traction, improved firepower, as the use of a turret allowed for all-round fire, a bulkhead to prevent an engine fire from immolating the crew, and two hatches for the crew to access or escape from instead of one, were just a few of the advantages of these still cheap vehicles. The only discernible advantages this tiny tank might have over the FT was its smaller size, making it harder to target, and a fractionally better top speed, certainly not enough to outweigh its serious shortcomings.

A Ford 3-ton tank, resplendent in a 3 tone camouflage pattern of probably green and brown with a light yellow or tan and black dividing lines, performs on a pile of rubble for the public in Omaha, Nebraska, circa 1919.
Source: Durham Collection
Camouflage-painted Ford 3-ton seen during a public demonstration in Omaha, Nebraska circa 1919, showing a small latch on the bottom of the commander’s hatch to hold it shut.
Source: Durham Collection

The Ford 3-ton, in many ways, exemplifies the US in WW1. It was small, inadequate, and far too late. The American version of the Renault FT was also seriously late, leaving the Americans having to use British and French-supplied vehicles instead (a single battalion equipped with the British-built Mk. V and Mk V* and various French-built Renault FT tanks to equip light tank battalions). In fact, no US-built tank served in combat in WW1 at all.

General John Pershing would end up arriving in France in June 1917 with no armored support at all. The Ford 3-ton received a huge order for production and no doubt the Ford Motor Company could have delivered these in vast numbers. Whether they would have found any useful function is unclear and, with the end of the war, they were quickly canceled – perhaps an indication that, all along, they were so seriously limited. Today, there are just two surviving examples of the tank, one at the National Armor and Cavalry Museum at Fort Benning, Georgia, and the other in the Ordnance Collection at Fort Lee, Virginia.

Profile illustration of the M1918 production version. Illustration by David Bocquelet, funded by our Patreon campaign.

Sources

Aberdeen Proving Ground Series: Tank Data 1. WE Inc., USA
Alexander, J. (2015). Briefly Famous. Self Published, USA
Crismon, F. (1992). US Military Tracked Vehicles. Crestline Press, USA
Ford Model T.net. https://www.fordmodelt.net/specifications.htm
Hunnicutt, R. (1995). Stuart – A History of the American Light Tank Vol.1. Presidio Press, USA
Jarret, G., & Icks, R. (1971). Portrait of Power. Normount Publishing, USA
Jones, R., Rarey, G., & Icks, R. (1969). The fighting Tanks 1916-1933. WE Inc., USA
Mroz, A. (2009). American Military Vehicles of WW1. McFarland and Co. Inc., USA

M1918 specifications

Dimensions 1.6 m high, 4.1 m long (including the tail) and 1.65 m wide
Total weight, battle ready 6,200 lbs. (3.1 tons) / 2,800 kg (2.8 tonnes)
Crew 2 (driver/commander, and gunner)
Propulsion 2 x Ford Model T 4-cylinder petrol engines delivering 35 hp
Speed (road) 8 mph / 13 km/h
Range 34 miles (55 km)
Fuel Petrol 17 US gallons (64.4 liters)
Armament 1 x 0.30 Marlin machine gun / 1 x 0.30 caliber Browning machine gun / 1 x 37 mm gun
Armor 12.6 to 6.35 mm
For information about abbreviations check the Lexical Index
Categories
WW2 German Heavy Prototypes

Projekt P.1000

German tanks ww2 Germany (1942)
Super heavy tank – None built

In tank terms, few tanks evoke more awe from the reader in terms of size and the specifications than the Maus, a 200 tonne behemoth from the tank-stable of the even more famous Dr. Porsche. It is also no secret that there is a certain following, especially online and in the media generally, for what could, at best, be described as ‘Nazi Wonder Weapons’. It is not that any one of these ideas could have won the war for Germany, that was simply not going to happen in 1945 regardless of whatever vehicle, missile, or plane the Germans developed. What they were, however, is a reflection of the giant level of engineering and imagineering which ran amock at times in Nazi Germany. A political mindset wanting a 1,000 year Reich was also thinking huge in every conceivable area, from giant planes to super-ships, rockets, and, of course, tanks. If the Maus impressed as a 200-tonne vehicle, then imagine a vehicle 5-times that weight; a true goliath.

Online, that vehicle has become known as the ‘Ratte’ (Eng: Rat), as some kind of allusion to its Maus-sized forebear, but the vehicle was less rat-sized and more landship-sized and was known under the less amusing name of ‘P.1000’.

The Men Behind the Tank

The first and most obvious character to have to consider in any project on a grand scale is none other than Adolf Hitler himself. Hitler loved grand thinking, big projects, and the whole sort of bigger and better concepts. This sort of superlative nonsense, which politicians like to bandy to this day, involves the idea that bigger is somehow better. This probably comes from a position of ignorance on engineering matters and, frankly, on military ones too. What use such a giant machine, several hundred or even thousands of tonnes in weight, might have is hard to say, but that is perhaps not the real point of such a grand project.

The point, from the mindset of a man with absolute power, was to be the biggest and, therefore, the ‘best’ in all areas. If an opposing force, such as the Soviets, could produce a giant vehicle, then, in the quest for superiority in military, political, and econiomic terms, Nazi Germany had to be able to do so as well.

What it also meant was that, despite the lack of military and engineering skills of Hitler, he did have the absolute power to order anything, no matter how impractical. This combination is perhaps why there were so many of these giant wonder weapon ideas. Any such project would need his support.

The second man in the mix is the most important in the story of the P.1000, the far less well known figure of Edward F. Grote (note that his name is repeated numerous times online and in books as Grotte, but is very clearly written as Grote with one ‘t’ in both British and German patents, so his name assuredly was ‘Grote’). Grote’s work on huge tanks had begun early, before the war had even started, but still in the context of a Nazi Germany confident in its own abilities. He had spent some time in the Soviet Union (USSR), and even though the two authoritarian states may have differed ideologically, they were surprisingly aligned on other matters, to the point where they would later agree over the division of Poland in 1939.

Edward Grote was a skilled engineer who, when living in Leipzig and running an engineering concern between 1920 and 1922, had received several patents for engines, in particular diesel engine innovations. These included methods of cooling and also lubricating those engines with oil under pressure. Grote’s interest in power transfer and diesel engines would be very useful when it came to designing large and heavy tanks.

The Soviets

The Soviets had, after April 1929, tried to emulate the French FCM 2C with a project of their own. To this end, they had engaged various foreign engineers and designers and this included the ideas of Edward Grote. Grote and his firm had, by 1931, risen to being the head and lead designer of the Soviet design team for this new giant tank. A design bureau known as AWO-5 was set up in Leningrad (now St. Petersburg) for him to conduct the design and development work. By 22nd April that year, the preliminary outline was ready. This became the first in the ‘TG’ (Tank Grote) series.

The Soviet TG or TG-1 tank was designed with the involvement of Edward Grote.

The design was innovative but it was expensive. The novel track design did not find favor and the BT-5 tank was selected instead. Despite attempts to improve the TG design, it grew heavier, more complex, and even more expensive until May 1932, when the Soviets finally killed the project. The cheaper and simpler T-35A was eventually selected for this role instead.

Grote, however, did not give up on the idea of an increasingly large tank with little concern for the restrictions of road and rail weight and gauge limits. In March 1933, he submitted a new, massive, and even less plausible vehicle concept to Soviet Marshal Mikhail Tukhachevsky, a key figure in Soviet military modernization during the 1930s. At over 30 metres long, this 1,000-tonne vehicle mounted guns and armor of the sort of size usually seen on battleships, running on no less than 6 sets of tracks, with 3 on each side. Grote had stepped beyond the heavy or breakthrough tank and gone full land-battleship. He determined that it would need twelve 2,000 hp 16-cylinder diesel engines (24,000 hp / 17,630 kW total) and a special hydraulic transmission.

Aside from the obvious production and utility problems of such a huge vehicle, the design had serious flaws, including the lack of a suitable engine and the Soviets quite sensibly rejected the vehicle. With that, Grote’s work in the USSR was over and he returned to Germany.

Sporting no less than seven turrets, Grote’s 1,000 tonne Panzer, as it appeared in Kraftfahrkampftruppe magazine in September 1937. Note that Grote’s name in the bottom right corner is clearly ‘Grote’ and not ‘Grotte’. There are 6 sets of road wheels shown. Although this was years since Grote’s work in the USSR, it can be assumed that this design was substantially similar to that early one submitted to the Soviets.
Source: Frohlich.

Grote, having returned to Germany, continued his engineering design work with more patent applications for developments in the field of transmissions, hydraulic couplings, and tracks. Other than a public feud with Gunther Burstyn in the German press, Grote’s work received little if any serious attention and, whilst his tank work had stalled, his engineer career had not suffered. In fact, by the start of WW2 in September 1939, he had managed to land a position with the Ministry of Armament and Ammunition in the Third Reich and was a Special Representative for U-Boat construction.

World War Two

It was in this capacity that Grote got the chance to promote his Fortress tank idea to Adolf Hitler in person in June 1942, when they met at an armaments conference. Hitler, perhaps swayed by the idea that the Soviets already had a nearly decades-long lead on the Germans with Grote’s work, and a general love of ‘big’ projects, agreed to allow Grote to develop drawings of a new 1,000 tonne Panzer. To assist Grote in the work, he was to team up with Dr. Oskar Hacker, the Chief Designer at Steyr-Daimler-Puch and Deputy Chairman of the Tank Commission.

In July 1942, Grote wrote to Dr. Erich Müller at Krupp, looking for assistance with very large mechanical gearboxes, such as Krupp was designing for a giant coastal artillery carrier known as the R-2. In his letter, Grote revealed that he was working on a design for a vehicle weighing several hundred tonnes and was going to use a 16,000 hp power unit.

Grote met with Dr. Müller in Berlin on 13th August 1942 and it is hard to gauge what Dr. Müller made of this new Fortress tank idea from Grote. Measuring a metre longer than his 1933 concept, at 35 metres, it was also 40% wider, at some 14 metres, but was also lighter, at ‘just’ 800 tonnes.

Once more, the vehicle was to be carried on 2 sets of triple tracks, although they were even wider now, some 1.2 m each for a total track width of 7.2 m. Being a little longer than the 1933 design, this vehicle also put down an additional metre of track length for 21 metres of ground contact, meaning a contact area of 151.2 m2 (21 m x 7.2 m). Weighing 20% less than the 1933 design and with more track in contact with the ground, this pushed the ground pressure down by 25% to just 0.54 kg/m2.

Rather than struggling to connect together a dozen 2,000 hp engines, Grote envisaged just a pair of engines and he had two options. The first was a pair of 1,623 litre V12Z 32/44 double-acting (24 cylinders and therefore also known incorrectly as the V24Z 32/44) two-stroke diesel engines from Maschinenfabrik Augsburg-Nürnberg (MAN). Producing 8,500 hp each at 600 rpm nominally, these engines were rated officially as being able to deliver 10,000 hp at 564 rpm.

MAN engine nomenclature. A ‘V12’ engine is actually a 24 cylinder engine in this system, as the number relates only to one bank of cylinders and not the total number of cylinders.
Cross-section of the MAN V12Z 32/44 diesel engine. Two of these giant units would be required for Grote’s 1942 800 tonne Fortress tank.
Source: Pearce

These were massive engines, each of which weighed nearly 51 tonnes without ancillaries. The historian Michael Frohlich provides a combined weight for this pair of engines as 128 tonnes. The alternative, and Grote’s preferred solution, was in the form of eight V-20 (40 degree), 134.3 litre, 34 tonne, 2,000 hp (at 1,650 rpm) Daimler-Benz speedboat engines. Those engines were a variant of the MB-501 he had considered back in 1933, but could now deliver the 2,000 hp desired, although the continuous hp available was rated as 1,500 hp at 1,480 rpm.


MAN V12Z 32/44 (V24Z 32/44) during production of one of the 6 copies made (left) and completed (right).
Source: Pearce and Frohlich respectively

Eight of those speed boat engines would weigh a total of 272 tonnes, whereas a pair of the MAN engines would be 102 to 128 tonnes – substantially lighter than the MAN-engine-option. It is also worth noting that 8 of those MB-501 engines working together was not pie-in-the-sky thinking – six of the very same engines were actually installed in U-boats U-180 and U-190.


Front and rear views of the Mercedes-Benz V-20 MB-501 marine diesel engine.
Source: Pearce and Frohlich respectively.

The 1933 design was impractical, as there was no suitable power unit for it. However, in 1942, Grote had two options, both of which would work. With these engines connected together and steering assisted by means of a Pittler-Thomas hydraulic transmission, this Fortress tank would be able to manage a calculated top speed of between 3 and 12 km/h. This was substantially less than the 60 km/h proposed for the heavier vehicle back in 1933 but was also far more realistic. It was also perhaps more useful in the sense that support vehicles and troops would be able to keep up with it in an assault.

This new design followed the same rough shape as the one from 1933, with a characteristic large well sloped glacis plate and multiple turrets. No armor thicknesses were specified at the time but, given that the 1933 concept used armor up to 300 mm thick on the front and 250 mm thick on the sides and that this vehicle is slightly longer and lighter, then protection levels may have been 10-20% less, although the belly and roof armor would likely stay the same as before. It was, afterall, completely unnecessary to have 300 mm of frontal armor, as nothing short of the main guns on a battleship could penetrate armor that thick at the time.

Grote requested no less than 20 designers to assist him in his work from Krupp, but this was declined and further details of the vehicle requested. In September 1942, Grote wrote to Dr. Müller confirming that he had details of the engines and was working on an initial draft of the vehicle. A month later, they met in Berlin to discuss the armament for the vehicle and both men were thinking big – really big.

Dr. Müller proposed the use of a pair of 28 cm guns for the main turret, along with two secondary turrets, each with a pair of 12.8 cm guns, and a pair of turrets with two 10.5 cm guns, along with numerous machine guns. All of these guns were to come from naval supplies made by Krupp, with the 28 cm guns as the primary weapon and the 12.8 cm guns intended for anti-aircraft work. Grote appears to have favored a submarine 8.8 cm gun in place of the 10.5 cm pieces suggested by Dr. Müller and also 20 mm MG 151 cannons instead of machine guns. The 20 mm cannon would be mounted in rotating turrets at the suggestion of the Luftwaffe (German Air Force). In a weight analysis of the design that Grote put together and which was scheduled to be presented to Reichsminister Albert Speer on 17th October 1942, the vehicle had grown from 800 tonnes to 900 tonnes, but the design was also much more refined and well-considered. The primary problem with the increase in weight was the increase in ground pressure from 0.54 kg/cm2 to 0.63 kg/m2 and there was a lot of unnecessary weight.

The model of the proposed vehicle shows a 5-turreted design with the giant battleship-style primary turret roughly in the center and the four secondary turrets arranged around it in a square.

The arrangement really looked almost childlike in the idea of cramming as many guns or turrets onto a hull as possible, seemingly with little thought as to how these might actually be used. The MG-151 turrets, 3 per side, one more on the roof of the front of the hull and another on the back of the roof of the primary turret, were small and inconsequential in the design, but the large naval-style corner turrets were not. Each turret mounted a pair of naval guns and they stuck up so far from the roof of the hull that they seriously interfered with the laying of the primary guns in the main turret. This main turret would therefore be limited to firing to the front, sides or rear, as any attempt to fire at 45 degrees would be prevented by the turrets unless the main guns were elevated over the top at the time.

The culmination of the work of Dr. Müller and Grote in October 1942 was a monster. An enormous hull surmounted by a single giant turret with the primary armament and four more turrets which were naively mounted in such a way as to seriously hamper the use of the primary weapon. Note that the roof of the hull at the front appears flat, whereas it is angled at the rear. Source: Frohlich
Seen from above and behind the lines of the hull with the distinctive peaked rear hull roof are evident. The lines are clean as they are stark, but there is no indication as to where any air intakes may be for the engines. Source: Frohlich

Apparently missing his 17th October deadline with Speer, Grote had finished revamping the design by the 20th. On this day, he sent Dr. Müller the new plans and they featured the distinctive battleship-style turret with a 10.5 meter wide coincidence-type rangefinder and a pair of the 28 cm guns suggested by Müller. The problem with this selection was that an ammunition loading system for the huge main guns was required and the system available was simply too heavy.

Further, the plan for 88 mm submarine-type AA guns for the rear turrets had been replaced with 128 mm guns instead. There was no reported reasoning as to why this change might be made other than perhaps the implication that more and bigger is somehow better. There is, however, some logic in reducing the number of different types of guns on a vehicle, as this would simplify supplies of ammunition and also parts.

Eleven days later, on 31st October 1942, Grote sent Dr. Müller new drawings, including elevations of the vehicle, looking for feedback. Dr. Müller and the Krupp firm remained silent. Seemingly frustrated with the lack of response from Krupp, Grote even threatened to try and take his gripes to Hitler personally and he finally got to meet once more with Dr. Müller on 17th December. Quite what machinations had happened behind the scenes are unclear, but historian Michael Frohlich records that Grote was told at this meeting that his services were no longer required. As for his P-1000 concept, it had, apparently, been replaced with a heavy tank project by Krupp.

Hitler (center in the white trench coat), Karl Otto-Saur (Ministry of Armaments in the brown uniform and red armband on Hitler’s left), Dr. Ferdinand Porsche (black hat, blue suit, stood on the right of Hitler), Dr. Müller (far left of the photograph in the brown suit and hat), and Colonel Holzhäuer (head of Wa Prüf 6) stood between Otto-Suar and Hitler wearing the black Panzer uniform. Source: Frohlich

Grote’s design had evolved by this time as well, to a simpler and more practical vehicle than the 7-turreted monster from October. The problems of the primary weapons being restricted by the smaller turrets was substantially reduced, with the front corner turrets now sunk into the hull and projecting vertically far less, allowing the main turret to rotate freely. Further, the turrets at the back were completely removed, saving weight. Further weight was saved by reducing the length of the 28 cm gun barrels in the primary turret.

Automotively, the vehicle remained the same essential shape, but the giant road wheels of up to 2.5 m in diameter had been replaced with 12 smaller, double, and non-overlapping road wheels which were in contact with the length of track on the ground. Two more of those road wheels supported the front of each track on the leading edge and would bear the weight of the vehicle when crossing an obstacle, like a wall or ditch. With 6 sets of tracks, that meant 96 of those double road wheels to support the full lengths of each track. Such a long track run under the side skirts would need some kind of support too and this would likely be in the form of track rollers, although how many is not known.

The December 1942 reworked P-1000, with the much more streamlined upper hull. Fewer turrets and shorter 28 cm guns meant a large saving in weight, crew, cost, and complexity. Note that the hull roof at the front now has a slight angle to it, with a central ridge line where the roof angles down to the sponson grooves, which are flat.
Source: Frohlich

Battleships and Guns

It is no surprise that a company like Krupp, which made turrets and guns for battleships, might select a naval style of mounting for the guns for the P.1000. It is even less surprising when it is considered that Grote had been working as a Special Representative for U-Boat construction. No doubt, that was also the reason he selected engines designed for U-boats. This is further reinforced by the selection of naval cannons for the rest of the armament, such as the 8.8 cm SK/C35 submarine anti-aircraft gun.

The primary turret, perhaps the most battleship-looking part of the design, is reminiscent in shape of the triple 28 cm mounting which was carried on the battleship Gneisenau, albeit with two guns. The first, longer, type of 28 cm guns certainly appear to be very similar visually to those 28 cm Gneisenau guns. If those were the guns planned, they would be the 28 cm SK C/34.

The stern-mounted triple 28 cm/52 turret on the Admiral Scheer.
Source: Navweaps via US Naval Historical Center.

That gun could throw a 315 to 330 kg high-explosive or armor-piercing shell up to 40 km at a muzzle velocity of 890 m/s. Each of those 14.5 m long guns, however, weighed a little over 53 tonnes depending on the mounting. Two such guns would therefore be over 100 tonnes alone. Each gun was capable of firing a shell 3.5 times a minute, so two guns meant 7 rounds a minute – a full 2.2 to 2.3 tonnes of high explosives.

In his weight breakdown, Grote had allowed for ‘just’ 300 tonnes for armament, so the two guns alone, with no ammunition, accounted for a full third of that allowance. They may, however, have been the slightly older and shorter 28 cm SK C/28. That particular gun was lighter, just 48.2 tonnes per gun (96.4 tonnes total) and was 14.82 m long. It could fire a 300 kg armor-piercing or high explosive shell up to around 35 km at a rate of 2.5 rounds per minute. A pair of them would mean that with a suitable ammunition supply system the P.1000 could throw 5 rounds per minute at a target – over a tonne and a half of high explosives.

However, even those shorter guns appear to be too long for the shortened 28 cm guns shown by Grote, so he may have been planning an even shorter barrel to save weight. Regardless of which gun the P.100 was supposed to be using, the shells, the ranges, and the potential damage were huge.

Assuming each gun was to have a semi-useful supply of 28 cm ammunition, either armor-piercing or high explosive, then even the lighter shells were 300 kg each. Ten shells would add 3 tonnes, and 100 shells, 30 tonnes. If Grote was trying to emulate a battleship, then 100 rounds would have been the minimum he would be needing, so 30 tonnes is a reasonable estimate for the ammunition. Add to this the weight of the guns and 130 of the 300 tonne allowance (43%) is used up.

The design called for 12.8 cm guns for anti-aircraft work and, although the exact gun is not mentioned, it is likely to be related to the 12.8 cm Flakzwilling 40. Each of those guns weighed 4,800 kg, so the eight of them planned on the 20th October 1942 P.1000 would account for an additional 38.4 tonnes of weight. The gun fired either a light (26 kg) or heavy (47.4 kg) high explosive round for anti-aircraft work at a rate of 15-18 rounds per minute. Assuming, once more, a semi-useful ammunition load of 50 rounds per gun, enough for 3 minutes of continual firing, then this conservative estimate would mean an ammunition load of not less than 10.4 tonnes.

Adding that all up provides for at least around 170-180 tonnes of those 300 tonnes (~60 %) allotted for guns, which suggests that Grote was not far off on his assessment when other guns, machine guns and ammunition are considered in the matter.

A clue into just how large and imposing the sort of primary turret Grote had planned can be found to this day in Norway at the Austrått Fort. It is located on a finger of land jutting out across the fjord leading into the harbor at Trondheim. In 1942, to guard the approaches to Trondheim, a turret from the Gneisenau was installed on a concrete bunker. The triple 28 cm C/34 turret is today part of a museum open to the public.


The triple 28 cm C/34 gun turret from the Gneisenau at Austrått Fort, Norway. The people in the shot provide a good indication of just how large this turret really is.
Source: wikipedia via Lars Brattås and Bunkersite.com

Whilst the shape of the turret might be emblematic of that of a battleship, there is no way that the turret from the Gneisenau or a similar ship could have been used. This is simply due to weight, as the turret, such as that at Austrått Fort, is around 750 tonnes in weight with all three guns. Remove one gun (approximately 50 tonnes) and the turret is still 700 tonnes or so, three-quarters of the weight of the whole vehicle as planned.

That is not the least of the problems either for the main turret. Although no precise height was specified for the 1942 design, the original 1933 concept was to be a total of 11 m high. Even assuming the mounting of those 28 cm guns could match the +40 to – 8 degrees of vertical movement, as achieved in the Austrått Fort, this would still leave a substantial blind spot in front of the vehicle. Given the huge size of the guns and shells, that may not be such a bad thing. However, even with the recessed turret design from December 1942, the depression of the primary and secondary weapons is so poor that, up close, the vehicle would have no means of defending itself. Indeed, the ground clearance for the vehicle is so high some vehicles may be able to pass underneath.

Conclusion

If anything, the whole 1,000 tonne Panzer idea owed more to the somewhat fanciful concepts for land battleships floated around in the First World War, when they were rightly ignored by most armies as impractical. Nonetheless, the era between the wars, the resurgence of a powerful Germany, and the industrialization and military modernization of a no less authoritarian Soviet Union combined to form a setting in which such ideas were taken perhaps more seriously than common sense or military reality should have allowed.

It is not that large tanks were not in vogue between the wars, far from it. For example, of the designs which were actually built (and many more which were not), the British had made the A.1 Independent – a 33 tonne, 7.6 m long tank with 5 turrets. The French had made the FCM Char 2C, a 69 tonne, 10.3 m long monster. The Soviets had made the T-28, T-35A, and eventually the T-100 at 28 tonnes, and 7.4 m long, 45 tonnes and 9.7 m long, and 58 tonnes and 8.4 m long respectively. The Germans had already tried the large multi-turreted tank as well, with the Neubaufahrzeug at 23.4 tonnes and 6.7 m long. All of these vehicles had, whether as medium or heavy tanks, prove to be failures for a variety of reasons, not the least of which was how hard it was to command a vehicle with multiple weapons, weak armor, underpowered engines, etcetera. None of those vehicles were anywhere near the scale of the Festung Panzers Grote was designing, yet the respective national operators of them had all come to much the same conclusion already – they were too big and too hard to command.

After all of the work, the models, and their grand plans for a 1,000 land machine akin to a battleship, it had all come to nothing and done nothing more than waste time, money, and resources in the planning – all of which could have been used elsewhere. It seems that Grote’s work made surprisingly little impact either on Riechsminister Speer or even Otto-Saur. In a post-war debriefing interview conducted by Allied Intelligence, neither man really knew much and said even less.

Speer, for his part, talked of an entirely different project weighing 1,500 tonnes, with an 80 cm gun (the Sevastopol Gun), whereas Saur only recalled that Grote had worked in the Soviet Union for a 1,000 tonne tank in 1929-30 (he actually finished his work in the Soviet Union and was back in Germany by 1933). His statement is confusing in that he makes no direct mention of working with Grote on his ideas or describing them but was clear that the P.1000 project did not come from the Heereswaffenamt “because the HWA [Heereswaffenamt] had no people of the right type for such schemes, apart from the former head of the HWA, General Becker”. He did mention that the entire project was very hush-hush – just 5 people in total even knew of the contract for the vehicle. What this means is that Saur knew of the project, along with just four others according to him, yet he was not forthcoming on the project at all and the interviewees sadly did not press him further on the matter. Could the project really have had the sort of high-level interest that Grote implied in his letters or was it more that he was working on a project which was more viable in his own imagination than that of others. For sure, it is possible or even probable that Speer and Saur post-war would not seek to elucidate on their association with grand Nazi mega-weapons ideas, but this one was clearly pie in the sky anyway.

The later (and saner) version of the P1000, showing the large battleship turret and secondary turrets. Note the Maus next to it, show for scale.
small variation of the later design, with different side skirts and extra small caliber turrets on the side. Both illustrations by Pavel ‘Carpaticus’ Alexe.

3D renders of the first version of the P1000 mockup, courtesy of Gabriel Orosco

3D renders of the second version of the P1000 mockup, courtesy of Gabriel Orosco

Sources

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Frohlich, M. (2016). Uberschwere Panzerprojekte. Motorbuch Verlag, Germany.
CIOS report XXVI-13. Reich Ministry or Armaments and War Production. Section 16: Interview with Speer and Saur.
German Patent DE385516, Im Zweitakt arbeitende Verbrennungskraftmaschine, filed 25th April 1920, granted 24th November 1923.
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German Patent DE636428, Stuetzrollenanordnung an Gleiskettenfahrzeugen, filed 6th January 1935, granted 8th October 1936.
German Patent DE686130, Geschwindigkeitswechselgetriebe, filed 6th January 1935, granted 3rd January 1940.
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British Patent GB457908, Improvements in and relating to Change-Speed Gears, filed 5th February 1936, granted 8th December 1936
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French Patent FR817411, Dispositif de transmission d’un fluide sous pression, filed 5th February 1937, granted 2nd September 1937
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Navweaps.com 28cm/52 (11”) SK C/28 http://www.navweaps.com/Weapons/WNGER_11-52_skc28.php
Navweaps.com 28cm/54.5 (11”) SK C/34
http://www.navweaps.com/Weapons/WNGER_11-545_skc34.php
MKB Ørlandet http://bunkersite.com/locations/norway/orland/orlandet.php

Categories
WW2 British Infantry Tanks

Infantry Tank A.11 Matilda

British Empire (1934 – 1940) Infantry tank – 139 built

In September 1939, the United Kingdom and her Empire embarked on yet another war with Germany over the future of Europe. Despite a rearmament program started at the end of the 1930s, Britain had entered the war ill-prepared for the conflict to come. The Army was professional and mechanized and had new tanks, but it had too few of both men and machines. It also entered the war in some ways prepared for the last World War, expecting a more static type of warfare, but with a stern eye focussed on the need for heavy armor to protect the infantry. Two tanks, in particular, were the outcome of a reassessed tank program that decade – the A.11 Matilda and its bigger counterpart, the A.12 Matilda. These two tanks formed the bulwark of British armor in the campaign in France in 1940 and yet, despite success at Arras, only one went on to be a legend – the A.12. Its smaller and earlier sibling, the A.11, has since this time languished and even been lambasted as being somewhat hapless or helpless, underarmed, and underperforming. The A.11 Matilda was, however, an interesting and rather successful tank. Built so tough that German shells had trouble piercing its thick armor, the A.11 was a shock to the Germans when it was unleashed upon them at the Battle of Arras. Without its development, there would likely have been no A.12 Matilda in the form which went on to dominate the early battles of North Africa and later serve in the Pacific.

Origins

The A.11 Matilda has its origins in the late interwar period, as the British Army was reflecting on the future shape of a looming war with a well-equipped European land power. New tank developments were going to have to go beyond some rather silly ideas for barely bulletproof and minuscule tankettes from the mind of Messrs. Carden and Loyd, to something a little more survivable and useful.

Two men, in particular, were primarily responsible for setting the scene on which the A.11 emerged, namely Sir Hugh Ellis, Master General of Ordnance (M.G.O.), and Major-General A. E. Davidson as Director or Mechanisation (D.o.M.). Between them, and looking at how a future war would go, neither wanted a repeat of the slaughter of WW1 and there was clearly a need for a tank dedicated to just supporting infantry attacks. It would have to be well armored, so that guns like the rather excellent German 37 mm anti tank gun (Pak.36) would not be able to knock it out, and be able to screen following troops from fire. Thus, the Infantry Tank was born, with armor being a priority and firepower was to primarily focus on supporting infantry. That meant dealing with enemy machine guns, which were the primary threat to the troops.

Both men were skilled and competent in their fields, with Davidson also a respected engineer, but both still saw a future war generally along the lines of the last one. In debating the primary role of a new tank for 1934, therefore, it had to be one to support infantry (an ‘I’ or ‘Infantry’ tank) in the attack against enemy infantry and fortified positions. Enemy tanks could be dealt with by artillery, so a new tank really just needed heavy protection from enemy infantry and anti-tank guns as well as the means to deliver machine gunfire. As it had to support infantry at their pace, the speed was almost irrelevant. As these two men debated their plans for what kind of a new tank was needed and how it should work tactically, they consulted with Major-General Percy Hobart, who was the Inspector of the Royal Tank Corps (R.T.C.) at the time and proposed two solutions:

1)A small tank with a crew of two men, armed with machine guns and built in large numbers to swarm the enemy.
2)A heavy tank with a cannon.

The small machine gun-armed tank option was the first to be investigated and, in October 1935, the legend of vehicle design that was Sir John Carden was approached to develop this idea. A skilled engineer and talented vehicle designer, he was also the head of tank design at Messrs. Vickers Armstrong Ltd. This meant that whatever he designed, he could get into production quickly. It would also be a chance to actually produce a tank with a useful amount of armor instead of his diminutive tankettes.

Seen during maneuvers on a snowy French field in the Winter of 1939-1940, this A.11 shows how it was meant to prove infantry support – a heavily armored mobile machine gun advancing in support of and ahead of the infantry. Source: IWM

His rather crude initial sketch, finished on 3rd October 1935, was for this two-man small tank with a single turret and single machine gun. A week later, this sketch was taken by Sir John Carden to Colonel M. A. Strudd, the Assistant Director of Mechanisation (A.D.o.M.) and the A.11 was born under the code word ‘Matilda’.

It is commonly repeated online and even in some books that this name was selected after the prototype was seen ‘waddling’ like a duck. However, the connection between Matilda and Duck is unclear in and of itself in this false history, especially as that Disney character with the Matilda name only appeared after the war. The name was not penned after seeing it move, as it is written on 10th October 1935, when the tank was not much more than a doddle. The name was, in fact, just a company designation for the project – a code word to disguise what the vehicle was.

Sir John Carden’s original sketch of the A.11 shows a low and long vehicle with a small cylindrical turret. Clearly noted in the corner is a protection level of 60 mm.
Source: Fletcher

Just 11 months after the initial sketch, a prototype vehicle was finished. Known as A.11.E.1, it was delivered for testing and trials. Other than the suspension system chosen, the A.11 had a remarkably easy birth when it came to testing. The suspension had to be modified slightly and episcopes had to be fitted. The exhaust pipe had to be moved to a new location, in just one more of those small changes identified during testing to avoid problems in production vehicles. Indeed, that is the entire purpose of testing and the A.11 can be considered to have passed its trials and tests rather well. That is not to say that A.11, when it first rolled off the production lines at the end of 1939, was the same as the A.11.E.1. There were substantial differences – mostly to simplify production, to accommodate a radio, and to reduce the problems of bullet splash.

Design

Layout

The vehicle was very simple in arrangement. A crew of just two men controlled all aspects of the tank, from driving to combat. The driver in the front controlled the steering and propulsion via foot pedals and a pair of steering levers. Behind him, the commander controlled the turret and primary weapon, as well as covering the duties of commanding the tank in combat. These two men occupied a small, albeit adequately spaced fighting compartment separated from the engine behind them by a bulkhead.

The driver sat forward in the hull and was provided with a single, full hull width rectangular hatch above him. This large hatch was supported by two hydraulic cylinders due to its weight and had a single episcope in it for the driver.

A famous photograph of ‘Deoch’, an A.11 belonging to 4th RTR, seen in France 1940.
The driver is provided with a very large and simple hatch but only a narrow front view slit and a single rotatable episcope. The heavy armor around the tank and its small size is evident.
Source: IWM

The rear of the vehicle sloped sharply downwards over the engine bay. Perhaps the most distinctive feature of the A.11 was the lack of mudguards over the top of the track run. This is surprising, given how simple such a guard would be, whether in metal or even canvas (like on the Medium Mark A ‘Whippet’ of WW1) and the lack of a mudguard meant dirt and branches could be caught up in the tracks and dragged along the side of the tank or thrown up onto the engine deck. None of this improved either the mechanical or combat efficiency of the tank. In fact, the only effort to alleviate this problem was the addition of distinctive mini-track guards covering just the rear corner of the track run over the drive sprockets.

Seen during exercises in France during the winter of 1939-1940, this rear view of HMH 794 belonging to 4th Battalion R.T.R. shows substantial damage to the rather small rear track guards. Source: IWM

The hull itself had changed somewhat from the days of A.11.E.1. On the prototype A.11 (A.11.E.1), the hull side was fabricated as a simple two-piece construction with an offset vertical line of rivets about halfway down the length. On the production A.11 vehicles, this seam was retained but the rearmost panel was now also split from a single panel to two panels and also had to be riveted together. This added a little weight to the vehicle but simplified production by reducing the amount of cutting of the thick armor plating which was required. Gone too from A.11.E.1 was the large bolted-on glacis with the outer edges cut off at 90 degrees, creating a sharp vertical edge. This was replaced on the production vehicle with a new glacis riveted to the side plates and with angled outer edges.

The nose of the tank had also been simplified for manufacture. Gone was the multi-section front which formed not only the nose but also extended outwards on each side to support the front idler. On production vehicles, this nose was a single piece and was fully integrated with those front extensions, with the whole lot bolted to the hull.

Modified nose and glacis from A.11.E.1 (top) to Production A.11 shows the simplified front to support the front idlers. The original bolted-on glacis has been replaced with a fully riveted one and the original corners are also chamfered off to reduce splash.
Source: Composite image from various sources compiled by the author

It is noteworthy that, despite the riveted appearance of the tank, it was not made by fastening armor panels to a frame, but by simply riveting the heavily armored sections directly together.

Suspension and Tracks

The original sketch from Sir John Carden showed a suspension system substantially different from the one which the vehicle was subsequently built with. This early concept was a type of suspension similar to or taken from an early type of Dragon Artillery Tractor, like the Mark IIC. This was dropped by the time that the prototype A.11.E.1 was built in favor of a system based on that of the Dragon Mark IV Artillery Tractor, which was itself based on the running gear of the Vickers 6-ton tank (both vehicles produced by Vickers-Armstrong).

Vickers Dragon Mk. IV with the 6-ton-type suspension (left), and the Vickers 6-ton (right). Source: IWM and Beamish Archives respectively.

The tracks used on the A.11 were a medium pitch design made from cast manganese steel and featured no rubber pads for use on roads, but had a pronounced spud to gain better traction on soft ground.

The suspension on A.11 was to undergo a series of changes during its development as a prototype, but it remained essentially the same layout. This consisted of two large bogies on each side, each with an ‘arm’ on which there were 4 pairs of small roadwheels connected by leaf springs. Above each bogie was a steel-tired return roller. Just two return rollers each side left the A.11 with a pronounced sag along the top of each track run, forming three small undulations.

A.11.E.1 underwent small changes during its trials, with the switch from a toothed front idler to a smooth one and a change from rubber-tired rollers to steel-tired ones, both of which can be seen in photographs of A.11.E.1. The original bogies on A.11.E.1 changed too. Originally, these were a single piece consisting of that 4-wheel paired arm with the return roller integrated above them. This was separated for production, with the return roller mounted independently, presumably for reasons of cost and/or to simplify fabrication. They became a rounded half-column shape of casting which was bolted to the hull.

Changes to the front idler from A.11.E1 (top row) where it started as a toothed idler (top left) and was modified to be road (top right), compared to the simpler production idler (bottom).
Source: Composite image from various sources compiled by the author

The change from one-piece to a split design is easy to spot in photographs. However, harder to appreciate in these photos than this rather subtle change is that the modified suspension from one piece bogie and roller to a divided system moved the tracks slightly further out from the hull. Originally, the A.11.E.1 was 7’ 6” (2.29 m) wide and, with the new bogies, it became 7’ 8” (2.34 m) wide – 1 inch (25 mm) added on each side. It also meant that the track centers were no longer 6’ (1.83 m) apart, but 6’ 2” (1.88 m) apart.

The suspension, in fact, went through several permutations and tweaks to solve various problems and these were rather subtle. On the final production batch, the suspension units can be seen to still be a large single casting bolted to the side of the hull, but with the arm for the bogie completely independent of the arm for the return roller.

Evolution of the suspension for the A.11 was complex and subtle other than the switch from the original sketch (top). From top to bottom.

Top: Original sketch of the suspension from October 1935. This style of suspension was used on multiple designs from the early Dragon carrier to the ubiquitous ‘Bren Gun Carrier’
Second image: A.11.E.1 suspension upon delivery September 1936 showing that distinctive toothed front roller and the suspension modified from that of the Dragon Mk. IV with the one-piece bogies with the incorporated return roller.
Third image: The abandonment of the toothed front idler during testing.
Fourth image: Post-April 1937 suspension shown on the wrecked A.11 at Bovington. The large one-piece casting is bolted to the hull side (2 per side) and features a separate mounting for the bogie and for the return roller.
Source: Composite image from various sources compiled by the author

Armor

The armor was heavy – very heavy for the era. A standard thickness of 60 mm was applied on the front and sides of the tank, made from Vibrac 45 armor steel produced by the (Vickers) English Steel Corporation. The roof and floor plates were just 10 mm thick and made from Homogenous Hard tank armor and proof against .303 rifle fire.

In December 1936, splash tests were conducted at Farnborough and the mantlet on the A.11.E.1 had been found to be too easily damaged by sustained machine-gun fire, which would create burrs in the steel and lead to the mantlet becoming jammed. It also allowed the entry of bullet splash, both of which were unsatisfactory. The result was a redesigned mantlet for the production tank made from cast steel, which would chip away under the repeated stresses of concentrated fire and so would neither jam nor break up. It also reduced the chances of splash entering the turret.

The main 60 mm thick plates of the type intended for the primary armor had been tested at Shoeburyness in March 1937. Whilst the 60 mm thick rolled plate and 60 mm thick castings were sufficient to stop armor-piercing shots from the British 2-pounder gun, there was not sufficient additional protection to allow for a sufficient margin of safety. As a result, there was a suggestion of upgrading the thickness to 65 mm with a tensile strength of 75 tons (76 tonnes) to provide an additional margin of safety, although it does not appear that this suggestion was taken any further. If the armor was sufficient to stop the British 2-pounder (40 mm) armor-piercing round, which outperformed the German Pak 36 (37 mm) armor-piercing round versus armor plate, the protection would therefore be adequate as per the requirements.

Splash trials in November 1938 found that splash could enter through the large driver’s hatch, as well as through the engine louvers. On top of this problem, the bullet-proof glass selected by Vickers had the unpleasant characteristic of splintering when shot and had to be replaced. The result was that production vehicles were to gain a splash guard added horizontally across the glacis in front of the driver’s view slit to prevent small arms fire from ricocheting up in that direction.

Montage of the evolution of the driver’s vision slit area. Top row far left is A.11.E.1 after the addition of the driver’s episcope. The driver’s plate is clearly flush with no splash guard. Top right centre is the very first A.11 off the production line, once more showing a simple vision slit and a lack of splash guard on the driver’s plate. Top row far right is ‘Demon’ of 4th RTR, showing that vehicles without this splash guard entered service and that this featured on only some of the first batch. Middle row far left is ‘Dowager’ of 4th RTR next to Deoch of the same unit in France 1940 – Deoch had the splash guard whereas Dowager did not. Middle row far right is a 3rd production batch A.11 captured in France 1940 to illustrate the difference- this tank had a simple moving block flap which allowed for better visibility. This flap can be seen closed bottom row left in an A.11 lost in 1940. Bottom row right is the misnamed ‘Demon’ on display at the Tank Museum Bovington, showing a third production batch vehicle with the name from a first production batch vehicle.
Source: Composite image from various sources compiled by the author

Stowage and Head Lamps

Two large stowage bins were fitted to some vehicles, one either side of the driver’s cab, directly behind the headlamps. On the A.12 vehicle which followed the A.11, these stowage bins were moved forwards and downwards to flank the nose of the tank. Behind the curved front armor of the A.12, these front bins actually provide a misleading shape on the front of the A.12, giving it a full-width flush appearance when it is, in fact, a narrow nose-shape, just like the A.11. Moving those boxes forwards in that manner and making them integral with the vehicle did provide the advantage of additional protection for the A.12. During production of the A.11 in batches, these stowage boxes also changed position slightly. Final production vehicles have the headlamps in front of the stowage boxes.

Different styles of stowage boxes, with A.11.E.1 (top row left and right) with a low-slung box with unreinforced sides and a flat lid roughly level with the top of the glacis. On production vehicles, these boxes received a distinctive ‘X’ shaped reinforcement on all sides (bottom left). On the final production version, the boxes were raised to roughly match the shape of the front of the driver’s position and projecting slightly ahead of it (bottom right).
Source: Composite image from various sources compiled by the author
Headlamp changes from A.11.E.1 (top left), with the original boxed-in protected headlamps, to an early production A.11 (top right), where the headlamp position on either side of the driver’s position was retained, to a late production A.11 (bottom), where the stowage boxes were raised up, meaning the headlamps had to be moved forward.
Source: Composite image from various sources compiled by the author

Engine

Power for the A.11 was provided by a Ford V8 petrol engine delivering 70 hp, connected to a Fordson four-speed gearbox. Drive for the tracks was delivered from this gearbox via final drives at the rear to turn the sprockets. Steering was provided for through a system of clutch and brake steering (i.e. brake the right track to turn right and vice versa), as used on Vickers light tanks.

Cramped is one word, an efficient use of space however, might be another explanation for the very tight fit of the Ford 70 hp engine in the bay. The incredible thickness of the armor can be seen on the left on the top of the exposed side plate. Note that the cable seen at the top is a hatch release for the engine deck connected to the catch at the top left of the photo – it could only be released from inside the tank. Source: Fletcher

The engine was small and the result was a relatively slow vehicle. A top speed of just 8 mph (12.9 km/h) off-road could be attained, but this was not a problem at all for the design, as it only had to keep pace with infantry on foot. It has to be noted as well that this top speed was perfectly acceptable to the Army. In 1935, they had agreed to just 5 mph (8.0 km/h) and, whilst 8 mph (12.9 km/h) would be better, the A.11 clearly exceeded the minimum standard demanded. It is also noteworthy that, despite this relatively slow official top speed, during trials, A.11.E.1 actually managed a top speed of 10.9 mph (17.5 km/h) on a road and 5.8 mph (9.3 km/h) off-road, but this was not a problem at all for the design. The average speed the tank could sustain on a road was 8.17 mph (13.1 km/h) and 5.6 mph (9.0 km/h) off-road – again – better than the minimum standard required at inception. According to the tank manual from 1939, the engine was fitted with a governor which limited the top speed to 8 mph (12.9 km/h), although it is not clear what form this governor took and whether it could be removed by troops in the field.

Running on petrol, the engine was fed by internal fuel tanks which held 43 Imperial gallons (195.5 liters) for an official maximum operational range of 80 miles (129 km). The fuel consumption rate was recorded during trials as 2 gallons (9.1 liters) per hour on-road and 1.8 gallons (8.2 liters) per hour off-road, meaning that the A.11 could operate for up to 21.5 hours of road use and 23.8 hours off-road. Assuming 21 hours of on-road use at its sustained speed of 8.17 mph (13.1 km/h), this would mean a maximum operational road range of 171.6 miles (275 km).

Turret

The turret was made in a single piece from a substantial casting 60 mm thick all round. Provision was made for a single piece of armament – either a Vickers .303 caliber machine gun or the somewhat beefier .50 Vickers machine gun instead.

Almost cylindrical in shape, the basic elements of the A.11 turret were the same as drawn originally by Mr. Carden. The cylinder was angled at the back, providing a little more space. The front carried forwards the trunnions for the main gun, all within this one-piece casting.

Atop the turret was a simple circular hatch that opened in 2 semi-circular pieces. On the left side of this front half-circular hatch was the single episcope for the commander.

Turret roof of T.3347 showing the unusual split hatch. Source: Chris Stillito, Armour in Focus

The original turret casting for A.11.E.1 had been a little more complex than on the production model, where the pronounced half rim running around the front of the turret and projecting from the sides was blended into the casting. This hard rim can still be discerned on the production turret, but in a more rounded and more subtle form, although the purpose was still the same – to reduce the chances of ricochets up the sides of the turret hitting an exposed commander. Despite appearing to be cylindrical, the turret was not. It was actually asymmetrical, with a swell offset to the rear right and the cast area for the armament offset to the front left. This offset-casting at the front meant that the trunnion mount can be seen on the right hand side of the turret but not on the left and the reason for this offset is obvious – it allows the commander to share space with the gun. With the primary (and only) weapon on the A.11 being the single machine gun, it was belt fed from the left. Setting the gun off slightly to the right allowed the commander to operate the gun and reload it much more easily.

Two more small features of note on the turret include a small triangular bracket on the rear right-hand side for mounting a radio antenna base for the No. 11 Wireless Set set inside. The second notable feature is the pair of mounts for the smoke grenade launchers, one on each side of the turret and operated by cable from inside. Both of these additions appear on the production vehicle and would enhance the fighting capability of the tank. Smoke could be used to screen the infantry from enemy observation (and therefore their fire) and obviously the addition of a radio would assist in coordination.

The changes from the A.11.E.1 turret (top row) are readily apparent when compared to the production A.11 turret (bottom row). Changes include a slightly reshaped rear, the blending-in of that hard rim around the top edge of the front half, the addition of smoke grenade launchers on each side, the radio antenna base and the repositioning of the episcope for the commander.
Source: Composite image from various sources compiled by the author

Radio

No radio was fitted to A.11.E.1, presumably as a cost and complexity saving measure. In fact, right from the outset in 1935, no wireless set had been planned for A.11. This would be rectified by the time the tank entered production and a No.11 wireless set would eventually be fitted as standard on all production tanks, although this would obviously add weight and take up valuable space inside. The No.11 Wireless Set had only become available to tanks after 1938, so the A.11 design predated it – nonetheless, adding the radio to the A.11 was a good idea even if it came at a price. A mount for a radio antenna base was fitted to the rear right hand side of the turret and also to the upper right hand side of the hull just behind the turret.

Armament

The philosophy behind the A.11 design was for a tank that was able to support infantry. It would accomplish this by providing not just a mobile protective shield in front of them, but also by suppressing enemy positions with machine gun fire. It was the machine gun, not the cannon, which was the primary choice for killing enemy troops and destroying machine gun positions, which were the major threats to the infantry. In 1935, the primary armament for A.11.E.1 was simply to be the standard water-cooled .303 caliber Vickers machine gun, albeit with a short note which followed saying “we can try our idea of M/C gun, but this is not so urgent”.

‘M/C’ in this context may be taken to mean ‘Machine Cannon’ i.e. a heavy machine gun with added anti-armor capability over the standard .303 machine gun or another compact gun capable of firing small high explosive charges as well. The details were clearly not finished, as the priority was to get the tank into development as soon as possible. The small turret would make the fitting of a larger gun harder but not impossible. For the development of the A.11, just two guns were selected as possible armament, either a .303 calibre Vickers machine gun or its heavier counterpart, the 0.5 calibre Vickers machine gun. Whatever ‘machine cannon’ Sir John Carden and Colonel Strudd were discussing in October 1935 is not known.

Vickers .303 calibre Mark IVA machine gun.
Source: The Vickers Machine Gun
Vickers 0.50 calibre Mark V heavy machine gun
Source: The Vickers Machine Gun

Both types of machine gun were available with a variety of ammunition, from a lead core ‘normal’ bullet suitable for general use to an armor-piercing round. When it comes to the common complaint about the A.11, that it was under-armed, the existence of armor-piercing ammunition for both guns has to be taken into consideration.

For the .303 calibre gun, armor-piercing rounds had been available since WW1, as had incendiary rounds. The Mark.VII.W.z Armour Piercing round of 1917 (known later as the W Mk.Iz from 1927) was a 174 grain (11.28 gram) cupro-nickel jacketed bullet with a 93 grain (6.02 gram) steel tip. Travelling at 762 m/s, the bullet was designed to meet a requirement that 70% of rounds could penetrate a 10 mm thick armor plate at 100 yards (91.4 m). An effective anti-armor range of 100 m does not sound like much, but was perfectly adequate to deal with close-by enemy positions and also for suppressing protected targets further away.

For the 0.5 caliber gun, the armor-piercing round was known as the ‘Armour Piercing W. Mark 1z’ and also featured a hardened steel core. The penetrative requirements for this round were the same as for the .303 AP round – namely that, 7 times out of 10, it would be able to penetrate 18 mm of armor plate at 0 degrees and 15 mm at 20 degrees vertical, all at 100 yards (91.4 m). A tracer version of this round, known as the Semi-Armour Piercing (SAP) Tracer FG, came in various marks and there was even an incendiary version of it, known as the ‘Incendiary B Mark I.z’.

Whilst the .303 was an ideal weapon for suppressing enemy positions, mowing down enemy troops, and dealing with soft skinned vehicles, it was not suitable for picking off enemy forces behind a shield, like a gun crew. It was also not suitable for dealing with light enemy armor. The option of mounting the .50 caliber version removed that problem at short ranges. Both guns were perfectly adequate for general work, with acceptable accuracy on target out to at least 1,500 m. Both versions were virtually indistinguishable from each other when fitted into the turret and concealed within the large cast armor housing over the water-cooling jacket, although only troop leader’s tanks were fitted with the 0.50 caliber, at least for 4th R.T.R. By the end of 1939, the idea was for 16 of the 50 A.11 tanks belonging to 4th R.T.R. to be armed with the 0.50 Vickers.

Some 3,000 rounds (12 belts) of .303 caliber ammunition were to be carried as standard, which would be sufficient for just 6 minutes of continuous automatic fire. In the trial photos, there is one that appears to show half a dozen ammunition cans on a shelf on the right-hand side. Assuming this was an attempt to carry more ammunition, then that would be several more belts for perhaps as much as 5,000 rounds carried. Boxes for the .50 Vickers ammunition held just a single 100 round belt, such was the greater size of the round. Assuming the ammunition stowage for both guns was to be proportional, this would mean 1,200 .50 Vickers rounds, enough for just 2 minutes of continuous fire.

Experimental Work

A.11E1 – the first A.11 made, was used in the proving trials as the test-bed for a mine plough. This mine clearance device, made by Messrs. Fowlers of Leeds, would be pushed ahead of the tank and literally plough enemy anti-tank mines from the ground in front of the tracks and displace them to the sides. Should one go off, it would be well away from the underside of the tank.

This was a notable success as both a device and a mounting for the A.11, and subsequent batches of A.11 had the mounting points for this mine-plough added.

Fowler coulter mine plough fitted to HMH 788 – the first production A.11. Note the addition of tubular receptacles on the front of the hull either side of the driver’s cab for attaching part of the device. Also notable is the means of raising and lowering the device via the chain drive at the rear and the unusual tubular framework at the front of the mine plough, which was a later addition to the design. Source: Fletcher
A.11 ‘Gourock’ belonging to 7th Battalion Royal Tank Regiment ‘somewhere in France’, showing the power-take-off (PTO) fitted at the back, along with the winding mechanism to raise and lower the Fowler mine plough equipment. Note the chalked number on the back. This was a shipping identification. Although the color of the circle on the rear of the turret cannot be discerned, the only vehicles so marked were those assigned to C Company 4th R.T.R., and ‘D’ Company 7th R.T.R. As this is a 7th R.T.R. tank, this vehicle is identifiable as being assigned to D Company. Source: Brown

Production and Delivery

A contract for the production of 60 tanks was made at the end of April 1937 and, a year later, another order for the same amount was signed, meaning a total of 120 production tanks (121 total A.11s if the prototype is included). This would be enough to provide tanks for two whole battalions and the official name of the tank should leave no doubt as to what its purpose was – ‘Infantry Tank Mark I’ – a tank to support the infantry.

By January 1939, however, the vagaries of military procurement had become real and a third-order was placed for just 19 tanks. This was because the A.12, a larger, better armed and improved infantry tank, was being ordered and the A.11 and A.12 would now be issued across three battalions rather than two.

The first production A.11 off the production line. In this head-on view, the offsite of the machine gun to one side is evident, as is the very narrow profile the tank presents front-on to an enemy. Note that the mounts on the side of the turret, which look like ‘ears’, show that the addition of smoke dischargers was to be a standard feature for all production vehicles. Note that, although there is a horizontal splash guard on the glacis, there is no splash guard on the top edge of the driver’s plate. Source: Fletcher

By 1st February 1939, the first batch of 37 A.11s were delivered. This new tank was then issued to three battalions of the Royal Tank Corps (R.T.C.), specifically the 4th, 7th, and 8th battalions. The 4th Battalion R.T.C. was, at the time, at Farnborough, 7th Battalion at Catterick Camp, and 8th Battalion at Perham Down.

Each battalion consisted of three companies, each of which had five sections with 3 tanks apiece. On top of this, each battalion possessed a command company with 2 active tanks and 2 in reserve. There was, therefore, a theoretical strength of 45 tanks per battalion plus the 2 command tanks and 2 in reserve, for a total strength of 49 tanks, although this was meant to be 50 with an additional ‘spare’. The actual rollout was slightly different, with just one A.11 allocated to the command company, whilst the rest went to the combat companies. The second tank in the command company was a single Light Tank Mk. VI.

On 4th April 1939, these battalions of the R.T.C. were renamed as battalions of the Royal Tank Regiment (R.T.R.). With serious tensions in mainland Europe and the potential for a new war with Germany in the offing, the British Army began preparing a force to fight on the continent. After the declaration of war against Germany on 1st September 1939, the 4th, 7th, and 8th battalions R.T.R. (often simply named 4th, 7th, and 8th RTR) were formed into the 1st Army Tank Brigade (A.T.B.) under the eventual command of General Pratt although, initially, it was in the care of Colonel Caunter until 20th October. By the time of the outbreak of war, just 66 A.11s had been finished and delivered to these units, but the Brigade would be used to reinforce the British Expeditionary Force (B.E.F.) under General John Gort. The 1st A.T.B. started shipping out to France before the end of September, with 4th R.T.R arriving first and followed in the spring by 7th R.T.R. This delay was unfortunate, but it did mean that 7th R.T.R. could bring with them 23 of the new infantry tanks, the A.12, as well as more A.11s. It should be noted that, even though this tank was on issue to the Army and being deployed ‘to war’, the first deliveries of A.11 tanks to training schools did not take place until July 1939, months after the first tanks were delivered to units. It is recorded, however, that a single ‘Matilda’ tank was used in Brigade exercises in 1938 by the 1st Battalion Royal Berkshire Regiment, which would have to be A.11.E1, as no production vehicles had been finished by that time.

Like any tank production, the A.11 production was done in batches and various changes crept in during this process. The very first batch is distinguishable from later batches by the fact that the headlamps were mounted high up on the hull in front of the turret. Later batches had these headlamps moved lower down and further forwards towards the nose of the tank, as they would otherwise interfere with the Fowler mine plough.

The production of the A.11 was canceled by order of the War Department in June 1940, after the Battle of Dunkirk, although the final two vehicles did not clear the production line until August that year. By that time, a total of 139 A.11 tanks had been built by Messrs. Vickers Armstrong on Tyneside.

Army tank units are equipped with tanks possessing heavy armour, relatively low speed and high obstacle-crossing power. They have no weapons for their own close support other than smoke projectors, nor have they any special reconnaissance sections. Thus they are not
designed to act independently but in co-operation with infantry and artillery.
By virtue of its high degree of fire power, mobility and protection, the infantry tank is pre-eminently an offensive weapon of great effect in battle
”.

British Army Training Pamphlet No.22, Part III: Tactical
Handling of Army Tank Battalions – Employment, September 1939

A.11 belonging to 1st Army Tank Brigade on maneuvers in France, Autumn 1939. Source: The Tank Museum, Bovington

Camouflage, Markings, and Identification

In service, the A.11 was painted in the standard War Office-approved khaki green no.3 as a base, with a pattern of dark khaki green over the top.

The 4th Battalion R.T.R. used a ‘Chinese Eye’ symbol, which was a hang-over from a tradition inherited in 1918 from 6th Battalion R.T.C. The eye was painted with an iris-colored blue and outlined in black and was painted with one eye on each side of the turret.

Each vehicle is also identifiable by its War Department Index Number ‘T-……’ and a vehicle registration mark (VRM) consisting of three letters followed by three numbers. To be consistent with VRMs used on public and commercial vehicles of the time, the lettering on the plates was either silver or white on a black background. As of the end of 1940, the Army dropped the practice of using civilian registration numbers.

Unidentified A.11 of 4th R.T.R. seen during maneuvers in France 1940, cunningly concealing itself behind a giant haystack. Note the radio antenna on the hull mount. Source: IWM

As a point of some confusion, vehicles being sent overseas also received a number chalked onto the side, which can cause confusion, but has no relevance to unit identification. The number was simply part of the transportation of the vehicles.

Battalion commanders would fly a tricolor rectangular pennant (1’ 6” x 3’ / 46 x 91 cm) marked (top to bottom) Green, Red, and Brown, with a white 4 or 7 in the top left corner. Company Commanders would fly a 9” x 1’ 7” (23 x 48 cm) pennant (rectangular with a 8” / 20 cm deep triangular cut out) either Red (A Company), Yellow (B Company) or Blue (C Company). Black triangular pennants (9” x 1’ 1” / 23 x 33 cm) were flown by Section commanders, with two diagonal (2” / 5 cm) stripes to indicate which section as follows: Red (Sections 1, 6, and 11), Yellow (Sections 2, 7, and 12), Blue (Sections 3, 8, and 13), Green (Sections 4, 9, and 14), and White (5, 10, and 15).

As well as pennants flown from the radio antennas, there were also small signs painted onto the rear of the A.11 tanks, as well as the battalion light tanks. These painted signs also appear as small metal signs from time to time. These were to help with coordination by Commanders who would be able to see the rear of the vehicle and rear of the turret. Battalion headquarters tanks would have a diamond of either solid Blue for 4th R.T.R., or Red/Green for 7th R.T.R.

Company tanks from both battalions would use a large (9 inch 23 cm sides) Red triangle, B Company tanks a large (9 x 9 inch / 23 x 23 cm) Yellow Square, which may or may not have had a large black ‘B’ painted in it, and C Company a large (9 inch / 23 cm diameter) Blue circle. Of note is that, as 7th R.T.R. did not have a ‘C’ Company, it used this symbol for ‘D’ Company, as D was its third company. Larger symbols matching that Triangle, Square, and Circle format measuring 18 inches (46 cm) were used on the battalion’s A.12 tanks.

Other flags which may be seen in contemporary images are not unit identifications, but signal flags which are a simple, yet highly effective means of communication in the heat of battle. The rectangular signal flags included a horizontal tricolor Red, White, Blue, meaning ‘Rally’, a diagonally bifurcated Red/Yellow meaning ‘Out of Action’, and a double bifurcated flag colored Black, Yellow, Red, Blue meaning ‘Action’.

On top of all of those painted signs, A.11s vehicles assigned to the B.E.F. also received a white square (9” / 23 cm) marking applied on each face of the tank as a recognition sign. On top of all of these were names individually applied to tanks by their crews. Tanks of 4th R.T.R. began with a ‘D’ and those of 7th R.T.R. began with a ‘G’. Examples include Dahlia, Deoch, Dowager and Gnat, Gossip, and Ghurka, respectively.

Camouflage in the field could be improved with the use of a tarpaulin over the body of the tank and included the use of a ‘dishpan’ attached to the turret antenna mount to change the shape of the vehicle under the canvas. Over this, a fine net was spread to conceal it from enemy aircraft.

A.11 Matilda belonging to either 4th of 7th R.T.R. ‘somewhere in France’, 1940, hidden under a ‘shrimp net’. Note the use of the ‘dishpan’ in the first photo used to change the shape of the vehicle and to spread the tarpaulin. Source: War Office Photo

Service

In the Cauldron of Fire

The 1st A.T.B. started shipping out to France on 13th September 1939, with 4th R.T.R assembling in the area of Vimy. By November, 4th R.T.R. was scheduled to be fully equipped with its complement of A.11 and A.12 tanks, consisting of 50 A.11s and 23 A.12s and had moved to Attiches, which lies south of the city of Lille.

Reinforcements, in the shape of 7th R.T.R., left for France on 30th April 1940, bringing with them 27 more A.11s and 23 A.12s. The first elements of 7th R.T.R. began to arrive in France in the first days of May. The 8th battalion R.T.R. was scheduled to follow in May, bringing another 23 A.12s and 27 A.11s. As it happened, 4th R.T.R. never received any A.12s and, although 7th R.T.R. made it to France, 8th R.T.R. never did. It is worth noting that the HQ of 1st A.T.B. also arrived in France prior to May 1940. The 1st A.T.B., therefore, embarked on its campaign in France understrength, with just the 50 A.11s of 4th R.T.R. Perhaps in an effort to improve upon their firepower a little, in the absence of A.12 tanks for the battalion, 15 tanks were to be refitted with the 0.50 Vickers machine gun at this time, with a sixteenth allocated gun unaccounted for. This allocation could be interpreted to mean a fair allocation of five .50 Vickers machine guns to each company (15), with the sixteenth possibly for one of the two HQ Company A.11s.

April 1940 was primarily spent moving in anticipation of a German attack, as 7th R.T.R. made its way to reinforce 4th R.T.R., which by 12th May was in the area around Pacy. When the German attack finally came that day towards the Meuse, their advance was expected to be delayed, but they rapidly crossed this large natural barrier. The Germans had moved on Belgium originally, on the 10th, and in a rush to get their tanks into the right place, the tanks of 4th and now 7th R.T.R. were to be sent to Brussels via Orchies, departing on the 13th and 14th.

The journey was not long and the tanks of 4th R.T.R. were unloaded on 14th May east of the town of Hal, whilst those belonging to 7th R.T.R. were unloaded at Berchem, just south of the city of Antwerp, Belgium.

On this deployment to war, the relative compliments of tanks for both units were:

Armored vehicles of 1st A.T.B. as of 14th May 1940. Source: Author

The vehicles of 7th R.T.R. were ordered to occupy the Soignes Forest (Foret de Soignes) on the 15th, the day after arriving at Bercham. With the rapid German advance, British Corps HQ ordered a general withdrawal to avoid being cut off, leaving two sections of A.12 tanks at Ermite to cover the withdrawal. The withdrawal could not be completed by train due to bombing by German Stukas at Enghien, so continued by road instead, with the A.11s put at the back of the column. By 1100 hours on the 17th, the withdrawal halted and turned to move back towards Hal to block the advance of a German armored division. These Germans never showed up at Hal and, at 1500 hours, the withdrawal began again in the direction of Orchies. Here, 1st A.T.B. prepared for combat against the invading Germans when 4th R.T.R. occupied positions to the south and east of Orchies, whilst 7th R.T.R. moved to positions in the north. Once more, the Germans did not oblige and, in an effort to find the enemy, reconnaissance was carried out in the direction of the town of Evin before both units were moved again – this time to Vimy.

The intent was to use these tanks, in conjunction with 151st Infantry Brigade and 50th Infantry Division, in a counterattack against the German advance, although this operation was not able to be ordered until the morning of the 21st. In just over a week, therefore, a lot of ground (~120 miles) had been covered moving these units around to try and find the battle, and little more than some casualties from German bombing and a lot of wear and tear on the vehicles had been endured.

What the movement did, however, was to set the scene for perhaps the defining British battle of 1940 – the Battle of Arras. The wear and tear on the vehicles meant that, on the eve of that battle, the strength of 1st A.T.B. had been reduced to 58 A.11s, 16 A.12s and 12 light tanks. Many of these tanks were already in need of an overhaul but there was no time to do this.

Dreadnought and Dolphin seen in France with 4th R.T.R. 1940. Source: Pintrest

Arras and beyond

The German Army had executed its advance through Belgium faster than expected by Allied planners. The result was a degree of confusion and critical urgency on the part of the Allies to try and plug the gap in their own defenses. In just over a week (10th May 1940) since German forces invaded Belgium in Operation Fall Gelb (English: Operation Case Yellow), the primary British tanks for fighting the Germans had still not seen ground combat and had been sent to fill the gap in defenses which lay between Arras and Cambrai.

The British would not be alone in the battle. Their allies, the French, were there as well, trying to defend their own nation from the German advance. The British forces moving on the gap at Arras had with them the French 3ième Division Légère Mécanique (D.L.M.) (English: 3rd Light Mechanised Division). As a combined Anglo-French offensive, the forces arrayed at Arras in May 1940 are often referred to as ‘Frankforce’. It should be noted that Arras was not undefended – there was a garrison under General Petre but it was very small and stood no chance of withstanding a German assault.

The two British columns shown in red attack from the north and sweep around the west of Arras. To their right is the green column of the French supporting them. Source: alchetron.com

The British would not be going into battle blind. They knew of a large German force moving across the area in a strategic flanking maneuver to cut off the British to the north. This counterattack at Arras would be targeting part of that German effort and, if fully successful, would cut off the German line of advance and communication for their wider flanking maneuver. Initial contact with German forces had been made by reconnaissance troops of 4th R.T.R. on the night of the 20th at St. Amand. The order of battle for the British was for a three-pronged attack. The left column of this attack consisted of 4th R.T.R, under Lt. Col. Fitzmaurice with 35 A.11s, 6 A.12s (from 7th R.T.R., allocated as a reserve under the command of Maj. Hedderwick), and 7 light tanks, supported by 6th Battalion Durham Light Infantry (D.L.I.). The 6th D.L.I., would arrive late after having lost their trucks to German air attacks and having had to force march all night to cover 8 miles (13 km) to get into position. The same was true for men from 8th battalion D.L.I. as well.

Three miles away to their right was the second column consisting of 7th R.T.R., with 23 A.11 tanks, 10 A.12s, and 5 light tanks, supported by men from 8th Battalion D.L.I. The third element, positioned off to screen the right flank of this attack from the Germans was the French 3ième DLM with around 60 tanks. Although 9th D.L.I. was part of the 50th Division, it was held in divisional reserve along with the remainder of the Division.

Facing this combined force was the German 7th Panzer Division under the command of General Erwin Rommel. Gen. Rommel had planned on an afternoon advance by 7th Pz.Div. around the north-west of Arras in conjunction with the SS Totenkopf Division to its left and supported by the 5th Pz.Div. attacking to the east of Arras.

This German advance ran into the British and French counterattack on the afternoon of 21st May. It was the 4th R.T.R. (left column) which encountered the Germans first, running into fire from German anti-tank guns and artillery almost as soon as their advance began in the gap between Maoeuill and Anzin-st-Aubin. They began their attack at 1400 hours from the Arras-Doullens railway and started very well. Despite their exhausted state, they moved quickly to contact.

A.11 Matilda Daffodil, Drake, and Duck belonging to 4th R.T.R. attacking at Arras, as painted by the driver of Daffodil sometime after the battle, in England. Source: 4and7royaltankregiment.com via The Tank Museum

A German motorized column with men from the 6th Rifle Regiment of 7 Pz. Div. was found moving against Danville. It was stopped and shredded by this British advance. Despite German shelling, the D.L.I. advanced in good order supported by the tanks and moved into a line of German anti-tank guns. Radio silence had been ordered to achieve surprise and the result was that commanders ended up fighting almost independently of each other during the attack. In one incident, WO III (Warrant Officer 3rd Class) Armit, commanding one of the A.11s, found his .50 Vickers machine gun jammed and simply resorted to charging down on the German anti-tank guns relying on his armor alone to succeed.

Despite the problems of coordination, the attack was a resounding success and continued despite the molestations of enemy fire. The advance had crossed the La Scarpe River and then it dominated the area around Danville before moving off towards Achicourt crossing the Le Crinchon River. However, a serious blow was dealt to the coordination of the British advance by this column when Lt. Col. Fitzmaurice was killed by an artillery shell that struck his light tank. Nonetheless, the force continued its advance in the face of German resistance. The A.12s allocated to the advance were the target of much attention from German anti-tank guns, until finally the attack slowed down and was stopped along the line of the Arras-Bapaume road at Beaurains. This was at around 1530 hours, when the commander of the 50th Division, Major-General Martel, ordered a halt so that the right column could keep pace with the left column.

The right column had started off late and moved through Duisans. There, they ran headlong into some advanced German troops and transports, which were quickly destroyed. With that initial contact a success, the tired force was buoyed and, by 1500 hours, they encountered enfilading German fire from the West which had to be mopped up. This had delayed the column a little more and, although it had not stopped, it became obvious that a large enemy force of men and medium tanks was ahead of them at Warlus, on their route to Wailly-Ficheaux.

With the commanding officer of 7th R.T.R. (Lt. Col. Heyland) killed by enemy fire and the loss of radio contact, the attack was at risk of becoming disjointed, but Gen. Martel ordered the advance forward to contact in order to assess enemy strength, before being halted at around 1530 hours.

The attack had, bar for one unfortunate blue-on-blue incident between the British and French, been a resounding success. The attack had not reached the Sensee River as intended, but the Germans had heavy losses inflicted on them for relatively modest British and French casualties in a front which pushed the Germans back some 15 miles (24 km).

With the British attack halted, the Germans considered a counterattack. They were cognizant of the power of the Allied force arrayed ahead of them and now ready for a German attack. Rather than risk another costly black eye on the ground, the Germans instead turned to their superiority in the air to lead the way, with a 20-minute air raid by 100 dive bombers at around 1815 hours.

With enemy ground forces now moving against them, 4th R.T.R. was under a sustained assault, with their A.11 and A.12s arranged some 200 yards (183 m) behind the main infantry defensive line, providing much-needed fire support. As night fell on the 21st, a column of German tanks was detected moving along the crossroads 800 yards (732 m) south of Achicourt. Initially thought to be a tank from 4th R.T.R. coming back to the front, it was quickly realized that this German column was penetrating their lines and the 11 tanks of 4th R.T.R. were once more in combat, this time in the dark, and against enemy tanks rather than just infantry and anti-tank guns. The German attack consisted of 5 tanks* facing off against the 10 A.11s and single A.12 (from the 7th R.T.R. assigned to 4th R.T.R.) of the British about 250 yards (229 m) away. A short and fierce exchange of fire took place between the tanks, causing no losses on either side but resulting in a decision by the Germans to withdraw.

The right column of 7th R.T.R. had more success that evening, despite a bombing by German aircraft. That bombing preceded an advance by German tanks but, when British anti-tank guns of the 260th Anti-Tank Battery were brought up, several German tanks were left burning, as the rest withdrew once more.

Both columns had, therefore, encountered fierce resistance to their attacks by superior German numbers in men and machines and yet both columns had punched through the enemy forces a distance of around 5 miles (8 km) for the left column. This left the Germans to scrabble together counterattacks which were rendered useless by a combination of staunch infantry defense, rapid deployment of anti-tank guns, and the implacable armor provided by the A.11s and A.12s which remained operational. The tally of losses for the day was around 20 German tanks* completely lost with many more damaged and a trophy in the form of nearly 400 prisoners of war.

(*German tanks brought to Arras included the Pz.I armed with just machine guns, the Pz. II armed with a 20 mm cannon and a machine gun, and the Pz.IV Ausf. D armed with a short barreled 75 mm gun)

On the British side, 176 officers and men from 4th R.T.R. had been killed, captured, or wounded and another 50 from 7th R.T.R. Both 4th and 7th R.T.R. brought tanks back with them from the battle, specifically 4 light tanks and 12 A.11s from 4th R.T.R. although 4 of those A.11s were no longer fit for combat. Thirteen of the A.11s from 7th R.T.R. had survived along with 6 of their A.12s. The German losses for the action that day taken from the war diary of 7.Pz.Div. admits to the loss of 9 medium tanks, several light tanks, and 378 men missing or wounded.

“Our infantry tanks showed a definite superiority over the enemy tanks and the armour resisted direct hits from enemy A.Tk [anti-tank] guns quite easily and the bursting of the shells had no effect on the crews… the number of tanks available and the mechanical efficiency had been considerably reduced by the long marches which they had undertaken. If larger numbers of tanks had been available supported by stronger mobile columns a very great success might have been achieved. The attack showed the great power possessed by the side which is one step ahead of the other in tanks, i.e. in possessing armour which cannot be penetrated by the enemy anti-tank weapons”
General Martel – Account of offensive operations
carried out south of Arras 21st May 1940

Unwilling to allow the Germans time to assess that they had been bullied by a smaller force, 4th and 7th R.T.R. were withdrawn during the night to the town of Ecurie and, by dawn on the 22nd, to Vimy.

4th R.T.R. was to take up positions along the Givenchy Ridge and 7th R.T.R. positions east of the town of Souchez (north of Arras), supported by French tanks. The intention for the 23rd had been for 7th R.T.R. to advance to the west of Souchez, but this was canceled in favor of countering a German attack in the area around Carincy and Albain St. Nazaire, east of Souchez. Here, the A.12s of 7th R.T.R., armed with their 2 pounder guns, knocked out several German tanks followed by an attack on the outskirts of the town supported by the French. By the end of that evening, however, and despite repelling another German attack, the vehicles were paying the price of constant combat and little maintenance time, with two A.12s having to be abandoned with transmission problems.

Both 4th and 7th R.T.R. were having the same problems and, by the 25th, the two battalions became one in the form of the 4th/7th R.T.R., with their remaining strength of just 8 light tanks, 18 A.11s and just two A.12s, although one was suffering serious mechanical problems. The remaining vehicles, some of the wounded and what other elements could be spared for evacuation were sent in the direction of Dunkirk, where they had to abandon their vehicles.

Despite the heavy losses, the German attacks were unrelenting and the composite 4th/7th R.T.R. battalion was sent to Orchies to support the French and III Corps in their own attack planned for the 26th. By the time they got to the destination, III Corps had gone, the attack cancelled and they were ordered to Seclin instead, before being diverted to Dunkirk. By this time, the slower A.11s and perhaps the one A.12 which had not yet broken down were also ordered to Dunkirk, but more losses were suffered resulting from German air attacks.

In a bombing run, one A.11 was overturned by a bomb exploding nearby, another broke down and, by the time the unit reached the town of Fournes, just 13 A.11s remained.

From Fournes, the unit was ordered to Pont du Hern, but was low on petrol and, having been in almost constant combat and or movement, the constant wear and tear was culling the remaining tanks. Three were abandoned due to mechanical problems with the gearbox and tracks bringing the total to just 10.

The A.11 was not going to simply be marched to death, in fact, they had one more combat action to perform. This action took place in the town of La Bassee north of the city of Lens. Diverted on route to Pont du Hern on the road to Dunkirk, the 4th/7th R.T.R. was tasked with extracting the 1st Battalion Cameron Highlanders (part of 1st Division, II Corps) who were trapped in that town by the Germans. This was performed by advancing the tanks in a single line towards the enemy down the road, providing cover and raking the Germans with machine-gun fire as they did so. This time, however, the Germans were not facing a direct assault nor were they reliant upon poorly sited Pak 36s. Instead, the Germans used tanks in static positions and their artillery to break up the attack.

Just two of the 10 A.11s sent to the rescue at La Bassee managed to make it back to safety. These vehicles managed to get back to Dunkirk, where the tanks were abandoned and the crews evacuated.

It is perhaps surprising that 4th and 7th R.T.R. were not the only users of the A.11 in 1940. As part of 1st A.T.B., there was a brigade workshop operated by men from the Royal Army Ordnance Corps (R.A.O.C.). As early as 9th May, this unit was in France and working on repairing a pair of A.11s from 4th R.T.R. This is a perfectly normal arrangement for a level of maintenance which could not be done at the unit, with another unit where vehicles are repaired and then returned to the battalion for its operations. The R.A.O.C. provided invaluable support for 4th and 7th R.T.R., recovering vehicles when they could and getting them back into fighting order. On 22nd May, in the aftermath of the brutal clash at Arras, the workshop found itself potentially in line for an attack by German forces. In possession of a pair of A.12s and a single A.11 which they had recovered, they organized a defensive line which perhaps thankfully for them never came. Instead, they were ordered to move out on the 23rd, setting off with all three ‘Infantry’ tanks and towing another A.11 for a nominal ‘strength’ of two A.12’s and two A.11s. The A.11 being towed broke down and could not be recovered in time. However, the loss of one tank was countered as the unit moved, gathering strength to the point that, by the time it arrived at Mazingarbe, it consisted of 3 A.11s, one light tank (a Light Tank VIB), and 2 A.12s. At Mazingarbe, they tried to add another A.11 and an A.12 to their collection but were ordered back due to an allegedly unstable road. The R.A.O.C. workshop unit continued their work on the way to Kemmel, then Ploegsteert, Berges, and eventually to Dunkirk, where they arrived with 3 A.11s and 2 A.12s. From Dunkirk, like tens of thousands of others, the men were evacuated.

Finally, yet another 1940 user of the A.11 was the Baeuman Tank Company (B.T.C.). Named for its commanding officer, Brigadier-General Beauman, this was an ad-hoc unit formed from remnants of other units which became lost or disconnected in the Somme region during the battle of France, such as 1st Armoured and the 51st Highland divisions. Located in the area between Pont St. Pierre and Dieppe, on 27th May, this small unit managed to gather up 5 A.12s from the Rive Gauche Railway Station, all of which had mechanical problems but were otherwise available for combat. By 3rd June, this small unit had not only these 5 A.12s, but a total strength of 10 tanks which included 5 A.11s and crews as well.

The first deployment of this unit was a resounding failure when, on 5th June, it moved to Rouvray Aerodrome, notionally to stop a landing by German forces which was expected. On route, one A.12 broke down and had to be towed by another, which consequently caught fire. Another lost its clutch and, whilst two were salvageable, the third was crippled and dumped. The same story was true for one of the 5 A.11s, which also broke down. With a lack of time and parts, it was crippled and abandoned. On 7th June, they arrived just north of the town of Gratainville with a force of 4 A.11s and 3 A.12s, one Cruiser tank, and a Scout car they had collected to defend the river at Vascoeuil. From there, the company was moved to the west of the town of Gaillon, during which time another A.11 died from mechanical problems.

With just 6 ‘Infantry’ tanks left and running on petrol supplied by the French, the unit moved on to the town of Venables, where they came under enemy anti-tank gun and machine gunfire. During this encounter, one of the A.11s was struck by anti-tank gun fire in the track and crippled. It was rendered unusable by the British, with the expedient of shooting it with 2 pounder ammunition from an A.12. Another two ‘Infantry’ tanks were lost when the engine seized on one A.11, followed shortly thereafter by a broken track on an A.12, meaning it too had to be left during a withdrawal from the area. One more of these vehicles was rendered unusable by shooting it with 2 pounder gun fire, but this was not the end of the woes for these tanks.

One more A.11 was lost when it caught fire with a broken steering clutch, along with another A.12 and its broken track. This meant that, by the evening of the 11th, just one tank remained operational – a lone A.12. Reaching the town of Gauthier, it was cannibalized for track pins to go back and successfully recover the other A.12. In perhaps the most successful tank-recovery effort of 1940, the team not only brought back that A.12, but also an A.13 they found along the way.

It was, however, hopeless. The A.13 was in a bad condition and, with just two functional tanks (one of which had radiator trouble) and insufficient spare track pins, if one broke down they were left with trying to improvise some armored vehicles from their trucks. The unit withdrew to Cherbourg for evacuation, marking the end of the last A.11 use in combat in France.

Review of Arras

In combat at Arras, the crews of the A.11s were, in some cases, in virtually continuous combat against German forces for several hours. Analysis after the Battle of Arras on 21st May showed the substantial value that the heavy armor of the A.11 had brought. The Germans, though perhaps not expecting such an attack in such force, had sited their anti-tank guns directly facing the advancing British. No effort had been made to use a defilading position to fire upon the British tanks from the side. For what such a sitting might have been worth, the Pak.36 would still have seriously struggled to penetrate either the A.11 or A.12, although hits to the suspension and wheels could have crippled them. Both British infantry tanks had shown themselves to be virtually invulnerable to the admittedly accurate German anti-tank fire. One tank of 4th R.T.R. showed 24 separate impacts, including two from an enemy tank with no damage, and another 14 hits, all of which also failed to cause damage. Some of those hits had been received at ranges as close as 150 yards (137 m).

Able to resist the otherwise highly regarded Pak.36 so easily, it is no shock either that, during the unfortunate blue-on-blue incident with the French, one A.11 which received three hits from the gun of a French Somua S35 suffered no damage at all other than superficial dents. Even exposed to enemy artillery, the A.11 had proven itself to be a tough beast, with only a direct hit from German artillery taking them out of the fight.

Had it not been for the prompt and somewhat desperate action of Rommel in stopping the chaos in the German forces which the attack had caused, and by concentrating fire from artillery and using the German 88 mm guns at his disposal, the British tanks would have been virtually unstoppable.

It was there, at Arras, that the rather cheap and ‘silly’ A.11 had proved invaluable. It may have only had a single machine gun, but the armor was so heavy that the German 37 mm guns could make little impression on it and those vehicles which were lost were due either to break down, running out of fuel, or being crippled with their tracks shot off. It has been pointed out by some historians that it is after the Battle of Arras that the Germans quickly learned the shortcomings of their primary anti-tank gun – the 37 mm, and quickly ordered a replacement for the Panzer III in the form of a 50 mm gun.

The British tank force of May 1940 was a small one. The A.11s and A.12’s issued to 4th and 7th R.T.R. serving with the British Expeditionary Force (B.E.F.), supported by 2 battalions from the Durham Light Infantry, blunted the nose of the German advance. In the eyes of many, this single notable action gave the remnants of the B.E.F. the breathing room they need to escape at Dunkirk and shows the oversized strategic impact which a superior tank could bring when deployed in battle.

Despite making good use of a lot of captured tanks from Czechoslovakia and France, the Germans appear to have made no use of the A.11s they captured. They appear to have been gathered together and simply scrapped.

Successor and Conclusion

The A.11 is a curious design as it came in right at the end of what could be identified as interwar tanks and the first ‘modern’ tank for WW2. There is also a clear line of evolution from the A.11 Matilda to her bigger counterpart, the A.12, even though they would both, in effect, be developed in parallel with each other in the last couple of years of the 1930’s.

Almost as soon as the A.11 design was being finished and starting its service trials, a bigger and better replacement was already on the drawing board. Work, in fact, had already begun on A.12 by Spring 1937. That tank would end up delivered heavier than desired, with armor slightly heavier than A.11 and with an even more complex suspension system. If A.11 was a failure for its slow speed and focus on armor, then this would be even more true of A.12, which would not have the ‘excuse’ of being the first of a new class of tank. Instead of being a failure, the somewhat heavier (25.4 tonnes) A.12 became one of the outstanding tanks of the Second World War. The A.12 was more than double the weight of the A.11 and shared issues like large castings and the associated difficulty of manufacture, a complex suspension system, and relatively slow speeds. Not only that, but the A.12 is one of the few tanks which not only served during the entirety of the war but also in all theatres of it. The outstanding A.12 simply could not have existed in a vacuum or a situation in which the A.11 did not. That fact alone is sufficient to render any complaints about the A.11 moot but the A.11 was also clearly a decent tank in its own right as well.

Sir John Carden died in an aircrash in December 1935, meaning that the roll out of his A.11 design was left to the firm without his guidance. Thus he did not get to see his little tank go into action. Neither did he see the poor reviews of it post-war, as if somehow the lack of a slightly better armament or a more powerful engine could somehow have saved the B.E.F. from its defeat by the Wehrmacht in 1940. Notwithstanding the failures of 1940 and the retreat of the B.E.F. at Dunkirk, the A.11 proved itself a fearsome tank in combat and one which helped in the blunting of the German offensive at Arras. The reputation it has garnered since the war as a failure is simply unfounded.

Surviving Vehicles

As of 2021, there are just three surviving A.11s known. All three are at The Tank Museum, Bovington, England.

T-3447 – a number which should equate to a VRM of HMH 802 per Army issue lists, is an amalgam vehicle restored from wreckage recovered from a UK firing range. Currently painted as a vehicle belonging to 4th Battalion Royal Tank Regiment, the tank is a runner, albeit using a modern engine. The tank does not appear to have ever been issued.

T-8106, another A.11 and still a runner with its original engine, is also painted up as a vehicle belonging to 4th Battalion R.T.R. from 1940, including the B.E.F. recognition markings. It is currently displaying VRM PMX 466. This registration is one assigned to the third production batch of 19 A.11s after January 1939 and the ‘T’ number assigned should therefore fall between T-8101 and T-8119.

A third Matilda, ‘T’ number unknown and recovered from a firing range, is currently outside the Vehicle Conservation Centre, displaying numerous shell impacts. The vehicle is a wreck and unlikely to ever be restored.

5 views of the A.11 Matilda ‘Grouse’ belonging to 7th RTR. Illustrations by Adrielcz, funded by our Patreon campaign.

Specifications A.11

Crew 2 (Driver, Commander/Gunner)
Dimensions (L-H-W) 15’11” (4.85 m) L, 7’ 6” (2.29 m) W, 6’ 1.5” (1.88 m) H
Weight 11 tonnes
Engine 3.63 litre Ford V8 petrol producing 70 hp
Speed 8 mph (12.9 kp/h)
Armour 10 – 60 mm
Armament .303 or 0.5 Vickers machine gun

Sources

http://www.4and7royaltankregiment.com/1940-1941/
Battistelli, P.(2010). Erwin Rommel. Osprey Publishing, UK
Ellis, L. (1954). History of the Second World War: The War in France and Flanders 1939-1940. HMSO, UK
Fletcher, D. (1991). Mechanised Force. HMSO, UK
Fletcher, D. (2017). British Battle Tanks. Osprey Publishing, UK
Foss, C., & McKenzie, P. (1988). The Vickers Tanks. Haynes Publishing, UK
Forty, G., & Forty, A. (1988). Bovington Tanks. Halsgrove Publishing, UK
Brown, P. (2014). 1 ATB in France 1939-40. Military Modelling Vol.44 No.4. 2014
Brown, P. (2014). 1 ATB in France 1939-40. Military Modelling Vol.44 No.5. 2014
Smalley, E. (2015). The British Expeditionary Force 1939-1940. Palgrave Macmillan Press, UK
Solarz, J. (2008). Matilda 1939-1945. Tank Power vol. LXI. Warsaw, Poland
Obituary, Sir John Carden. Flight Magazine, 19th December 1935
Offensive Operations carried out South of Arras on 21 May 1940 – British Report. Gen. Martel papers. Imperial War Museum.
Tank Training Vol. II Part III Pamphlet No.2 .303-IN., Vickers Machine Guns Marks VI, IVA, IBV and I. (1936). HMSO, UK
Tank Training Vol. II Part III Pamphlet No.5 .5-IN., Vickers Machine Guns Mark V. (1937). HMSO, UK
War Office File 194/44 Matilda Infantry Tank, September 1936
War Office File 291-1439 British Tank Data
Williams, A. (2012). The .5” Vickers Guns and Ammunition. https://quarryhs.co.uk/Vickers.html
Zaloga, S. (1980). Blitzkrieg: Armour Camouflage and Markings, 1939-1940. Arms and Armour Press, UK

Categories
WW1 US Prototypes

Ford 3-man light tank

USA ww1 USA (1918) Light Tank – 1 built

The USA was a mess in WW1. War had broken out in Europe between the major world powers, killing hundreds of thousands and spreading to a front from the North Sea to Switzerland, also covering Northern Italy, the Balkans, Africa, and beyond. Yet, in the 3 years of war before the United States joined in, it had done little to prepare and certainly had not taken heed from the unleashing of tanks by the British in 1916 that a new epoch of warfare had begun. Thus, when it did finally enter the war in April 1917 on the side of the Entente, it did so with no tanks at all. In fact, no US-built tanks would ever see service in WW1, and the only tanks they used would be ones provided by the British and French. US development work was slow and even something as seemingly simple as just license building the Renault FT proved expensive and difficult to accomplish.

The Ford Motor Company had become involved too. Producer of the Model T, the world’s most common motor vehicle of the era, their production lines were well suited to mass production of vehicles for war and they tried their hand at their own tiny tank in the form of the 3-ton ‘Special Tractor’, which became known as the M.1918. This tank became available prior to the American-built version of the French FT, known as the M.1917. Whilst this US-built FT was still languishing unfinished in development purgatory, the Ford Company revealed one more attempt at a tank, this time a slightly bigger version of the FT for 3 men as a light tank, the unimaginatively named Ford 3-man Light Tank.

Design Philosophy

The vehicle itself was more than a little odd. It is not entirely clear why Ford chose to try and redesign the FT to enlarge it just a little, nor who was even asking for it. It is known that the US Army was disappointed with the tiny and mostly useless Ford 3-ton tank. Armed with just a single machine gun, that 3-ton vehicle had armor vulnerable to even small arms fire and lacked a turret. It was objectively worse than the French Renault FT by almost every measure and the most notable was the lack of firepower.

Side view of the Ford 3-ton tank, providing a clear view of the sprung double roller suspension unit and tail skids used to help cross a trench.
Source: US National Archives Reference 165WW-313-A-13

Even if the 3-ton had been fitted with a 37 mm gun in place of the machine gun, it lacked a turret to make the best use of that firepower, whereas the Renault FT could at least deliver fire all around. That French vehicle came in two types, a machine gun version and a light cannon version with a 37 mm gun. The M.1917 was to follow the same layout, so it makes a little logic that the Army might want both a cannon and a machine gun in one package. Trying to achieve this modest goal came at a price and the resultant design was a bigger, rather crude-looking FT-style vehicle trying to embody the good FT bits with the new requirement.

The French Renault FT light tank. Armed with either a single machine gun or 37 mm cannon, the tank was characterized by the large front wheel raised off the ground, a horizontal beam with the road wheels, and a low rear idler with the track’s return run carried in a curve across the top. At the rear is a large skid to assist in crossing a gap.
American M.1917 tank – the American version of the French FT. This example is at the Canadian War Museum. Source: JustSomePics via Wiki

Design

The general arrangement of the Ford 3-man Light Tank was to follow roughly the same lines as the Renault FT. The driver sat at the front, with a turret located above and behind him and, behind that, the engine. On each side was a track unit consisting of a large raised front idler, a series of road wheels under a protective cover, and a smaller rear drive sprocket. The center of the body was square, with vertical sides and a flat top on which was mounted a multi-sided frusto-conical turret consisting of 7 or 8 sections riveted or bolted together and surmounted by a large domed roof. At the rear of the tank, the engine bay had vertical sides and angled top plates over the engine, just like the M.1917, with a spine running lengthwise down the top of this section. At the rear was a large curved skid acting as a tail to help the tank cross ditches.

Front ¾ view of the Ford 3-man tank from a contemporary publication where the original background was edited out.
Source: Pinterest

Crew

As the name suggested, the tank was to have a crew of three. The Renault FT, M.1917, and Ford 3-ton all had two crewmen, with one of the crew having to do two tasks, as either commander/gunner or driver/commander. Clearly, it would be preferable and more efficient to divide tasks so the driver could concentrate on driving and the commander on command, which makes the design of the 3-man Light Tank all the more inexplicable. Here, the crew arrangement had a driver, located in the front left of the hull, in a small rectangular section jutting out of the body. Next to him was a small section which can be seen in photographs, with a circular port on the front. That was for mounting a machine gun in a ball mount and also featured a small vision slit in the side for the gunner.

The turret, however, with a large circular opening for the gun mounting, would be occupied by the commander, who would have to not only command but also control the primary armament as well. It has been suggested in some books that the primary armament was to be a cannon and a machine gun but, with only the commander in the turret, he would not be able to operate two guns at the same time. The alternative to all this was that the gunner was not in the hull but was, in fact, in the turret all along, to control the gun from there. This would leave the hull gun to the control of the driver. Whichever way it worked, one crew member was still going to have to do more than one job, unless the gunner was just to hop back and forth between hull and turret armament, in which case, of course, the hull gun was pointless and the gunner could just use the turret machine gun.

The most likely arrangement for the crew in the vehicle was simply that, gunner and driver in the hull and the commander performing the same functions as he would in the cannon-armed FT. This was certainly a major redesign and reworking of the FT idea just to cram in a third man and a limited traverse machine gun. Adding weight to this idea of crew positioning is that both the rectangular driver’s piece and the projecting section next to it for the ball-mounted machine gun could be raised to allow greater ventilation and vision when on a road march. Presumably, the large rounded top of the turret could also open or was provided with a hatch but, without photographs of this area, this cannot be established. Surviving photographs of the wooden mock-up also show a large rectangular forward-opening hatch on the glacis plate, presumably intended to serve as the access for the hull crew.

Armament

The goal all along was to increase the firepower over that of the Renault FT/M.1917. Due to their small size, those tanks could only carry either a machine gun or a short-barrelled 37 mm cannon.

The machine gun selected would possibly have been the 0.30 caliber Marlin M.1917 machine gun, although this had already been discontinued even on the tiny Ford 3-ton in favor of the 0.30 caliber Browning, or the Browning. Nonetheless, the Marlin was fitted to some M.1917 light tanks, so it is possible that this gun was to be the front ball mount.

0.30 caliber Marlin machine gun fitted into a mount identical to that used on the Ford 3-ton, prepared here for fitting to the US version of the French Renault FT, the M.1917. Note the aluminum cooling fins on the barrel and bag to catch the spare brass.
Source: Hunnicutt

The Renault FT and M.1917 also had the option of fitting the short-barrelled 37 mm. This single-shot Puteaux SA 18 cannon on the FT could be loaded and fired quickly and easily despite the small fighting space thanks to the small and light ammunition. These 37 mm x 94 rimmed rounds were a 500 gram Armor Piercing High Explosive round (Mle. 1892) traveling at 388 m/s, and a plain 560 gram High Explosive (Mle. 1916) round traveling at 365 m/s. This provided the tank with the ability to support the infantry by taking out enemy machine guns, as well as limited anti-armor capability, which would be useful for breaching small earthworks or gunshields, etcetera.

Interior view of a 37 mm gun, as postulated for the Ford 3-man. shown here in the housing used in the US version of the French Renault FT, the M.1917. Note how compact this gun is.
Source: Hunnicutt

If this gun was the one being planned for the Ford 3-man or if it was a larger gun, like a 6-pounder, is unclear. Certainly, the larger turret would have allowed for a larger gun breech inside, and the later M.1921 Medium Tank A used a very similar style turret face opening for a gun, which may be an indication for what the final gun mount would have looked like. The M.19211 Medium A used the model 1920 6 pounder tank gun, which was accepted for service in January 1920. Thus, in mid to late 1919, when this Ford 3-man Light Tank was being prepared, this gun would not have been ready for use.

Gimbal mount for the 6 pounder (57 mm) gun on the M.1921 Medium Tank A. Noteworthy is that, even in 1921, there still was no cannon and machine-gun mounting in use, supporting the premise that the Ford 3-man would only have a cannon in the turret.
Source: Pinterest
Inside view of the Model 1920 6 pounder (57 mm) tank gun, as used on the M.1921 Medium Tank A. Source: US National Archives

Armor and Dimensions

The Renault FT was a 6.5 tonnes, 5 m long, 1.74 m wide, 2.14 m tall light tank. With 16 mm thick armor on the well-angled front and vertical sides, along with 22 mm thick armor on the turret, the tank was well protected against anti-tank rifle fire at point-blank on all but the sides straight on. Despite this, the FT is not considered a particularly well-armored tank, even though this is the same sort of thickness as utilized on the British heavy tanks of the period. The thickness of the armor was really dictated by the need to protect against German anti-tank rifle fire, concentrated machine-gun fire, or the ‘reversed’ German rifle bullet.

Front view of the wooden mock-up of the Ford 3-man light tank, showing the distinctly Renault FT-shaped turret and the twin front position for the crew.
Source: DodgeGarage.com
Side view of the wooden mock-up of the Ford 3-man light tank, showing the distinctly Renault FT-shaped turret (substantially shorter than that of the vehicle when actually built) and the twin front position for the crew.
Source: DodgeGarage.com

Considering that the Ford 3-man Light Tank was meant to be an improvement over the Renault FT, it is surprising therefore that the armor was between 0.37” (9.4 mm) to 0.6” (15.24 mm) thick at its thickest, regardless of whether it was on the well-angled front or vertical sides. What this means is that the Ford 3-man, in a tank the same length and a little wider, taller and heavier, had armor thinner than even the thinnest part of the front or sides of the Renault FT. If the armor on the FT had been made that way to protect against German anti-tank rifle fire, then clearly the armor of the Ford 3-man was inadequate.

Suspension

The general suspension principle for the Ford 3-man was similar to the French Renault FT with the large raised front idler and rear sprocket. This was not the only feature copied from an earlier design. The common axle used by the front idlers, exposed outside the front of the tank, was a legacy of the Ford 3-ton.

Of the few photographs of the vehicle, one taken in the Ford plant of the unfinished vehicle shows the track run sagging down at the top, seemingly supported by simply what appears to be a raised section on the mud cover rather than rollers. The later side view of the tank taken outside shows the track raised and taut, held up by a pair of small return rollers instead.

The wooden mock-up also differs somewhat from the vehicle that was actually completed in that the pair of return rollers were not fixed rigidly to the hull, but were actually intended to be on an inverted spring leaf suspension unit in the same style as used on the Ford 3-ton tank.

One of the rare photos of the Ford 3-man, shown here in an Official Ordnance Corps image probably taken at the Ford factory. This also shows the Ford 3-ton in the background.
Source: Pinterest

Also visible in the outdoor photo is the cover over the road wheels, which is similar to that used on the Ford 3-ton, in that the wheels underneath are not rigidly fastened to this cover but instead appear to be in four pairs of wheels, with two pairs likely connected to either end of a leaf spring suspension unit under the cover. The Ford 3-ton had already switched to just this type of sprung bogie system under a side mud cover, so it is likely that this system was retained for this tank as well. An odd feature on the top of this mud cover is an ‘M’-shaped ridge of steel, the purpose of which is not known, but could be speculated as an attempt to either prevent the accumulation of mud or to help prevent wire or other debris from being drawn along the top of the mud cover into the sprocket.

Side view of the Ford 3-man Light Tank, showing the Renault FT heritage and the new, bigger rear end for the exhaust. Note how much taller the finished turret is than the original wooden mock-up with the Renault FT turret.
Source: Crismon

The tracks were at least something new to the design, or at least partially new. The tracks from the Renault FT and M.1917 were, like those of the Ford 3-ton, relatively simple flat plates with a raised spud on one edge to gain traction on soft ground. The Ford 3-man’s tracks were a little different, featuring what appears to be a spud pressed into the track plate, which also featured a small hole into which the tooth of the track sprocket would fit. The track links still used the same system of a plate riveted to a shoe underneath, into which the teeth of the sprocket could mesh. The addition of this hole would allow the teeth to be larger and improve the purchase of the track during motion. Seemingly unconnected and a case of convergent evolution on the subject of tank tracks, the Italian version of the Renault FT, which was also in progress at this time, known as the Fiat 3000, had a very similar style.

Fiat 3000 – the Italian improved Renault FT, showing the similarity in the track links on this tank to the Ford 3-man, despite seemingly no connection between the designs or designers.
Source: Pinterest

Engine

The Ford 3-ton had used a pair of Ford Model T petrol engines, with one engine powering each track, creating a task for the driver, who had to constantly adjust and balance the engines to keep the vehicle straight. This new vehicle would adopt the more powerful Hudson 6 cylinder petrol engine delivering 60 hp.

This engine was connected to a pair of modified Ford transmissions and then, by gearing, to a drive shaft to the drive sprockets.

Whereas the Ford 3-ton required one engine for each side with its own gearbox and could operate them singly to provide a turning moment, this vehicle was an improvement. The gearing system could operate either just a single transmission or both together to produce a 3 speed system with 2 forward gears and a single reverse gear.

A new ventilation and engine cooling system was also installed and the spine on the rear of the engine deck clearly still shows the influence of the Renault FT for the air intake. Cooling for the engine was provided by means of a water-filled radiator and fan, with the air for cooling and combustion drawn in through that spine and the exhaust all vented out of a large grille behind it.

Rear ¾ view of the Ford 3-man light tank, showing the extended engine bay and the distinctive double skid tail, as used on the Ford 3-ton.
Source: DodgeGarage.com
Another view of the Ford 3-man light tank, showing a small vision slit next to the front right crew position. The lineage from the Renault FT is undeniable.
Source: DodgeGarage.com

Production Outcome

The vehicle was still unfinished when the fighting part of WW1 ended and, yet, even while it was in development, the US Army Ordnance Department were seemingly so impressed with this rather crude vehicle that they still ordered 1,000 of them. With an order for 15,000 Ford 3-ton tanks and 1,000 of these, the war was potentially very lucrative for the Ford Company. With the end of the war and just 15 Ford 3-tons and this partially finished 3-man, however, any such ideas of a financial tank-building windfall was over for Ford. The vehicle was, at some point, tested to some degree by the Ordnance Department in 1919 and was found wanting. Just like the Ford 3-ton, this tank was too rear heavy and the design was not adopted. It is believed that the tank was later scrapped.

Conclusion

The Ford 3-man light tank is an oddity. A ton of effort and redesign work for little benefit. Redesigning the successful Renault FT just so it could include a third man and then to squander that opportunity by placing him in the front to operate just a single machine gun when he would really be more usefully employed in a bigger turret with the firepower concentrated there. With the Renault FT in mass production and being copied in the form of the American M.1917, what role could this vehicle actually perform? Larger, heavier and barely better armed, and yet with less armor, the vehicle stands out as a classic example of trying to improve on a design which was already close to perfection, and an effort which did not achieve success but instead failed utterly. The vehicle was simply worse in every way to the Renault FT with the sole benefit of another machine gun, a large price to pay for a completely new tank and presumably the reason why this vehicle managed just a simple example before being abandoned.

The Ford 3-man Light Tank in its complete form. Illustration by Andrei ‘Octo10’ Kirushkin, funded by our Patreon campaign.

Sources

Aberdeen Proving Ground Series: Tank Data 1. WE Inc., USA
Alexander, J. (2015). Briefly Famous. Self Published, USA
Crismon, F. (1992). US Military Tracked Vehicles. Crestline Press, USA
Ford Model T.net. https://www.fordmodelt.net/specifications.htm
Hunnicutt, R. (1995). Stuart – A History of the American Light Tank Vol.1. Presidio Press, USA
Jarret, G., & Icks, R. (1971). Portrait of Power. Normount Publishing, USA
Jones, R., Rarey, G., & Icks, R. (1969). The fighting Tanks 1916-1933. WE Inc., USA
Mroz, A. (2009). American Military Vehicles of WW1. McFarland and Co. Inc., USA

Ford 3-man light tank specifications

Dimensions 16’ (4.88 m) long excluding tail
6 ½’ (1.98 m) wide
7’ 9” (2.36 m) high
Total weight, battle ready 7.5 tons
Crew 3
Propulsion Hudson 6-cylinder petrol producing 60 hp
Armor 0.37” (9.4 mm) to 0.60” (15.24 mm)
For information about abbreviations check the Lexical Index
Categories
WW2 French Projects

Jacquet Assault Train

France (1944) Articulated vehicle – design only

Victor-Barthelemy Jacquet is not a French designer with golden name recognition, like Louis Renault or Colonel Jean Estienne, the fathers of the Renault FT and French tanks respectively. Indeed, virtually nothing is known of him outside of a few patent applications submitted between 1922 and 1944. It is this final patent, submitted at a time when France was being liberated from the Germans by the Allies, which was perhaps one of the oddest tank designs of the war – a train tank or, in modern parlance, a cybernetically connected articulated armored fighting vehicle.

The Man

Little can be found about Victor-Barthelmy Jacquet. What is known is that he submitted his first patent in France in 1922, followed by 7 more filings in Great Britain and France over the next 22 years. His penultimate patent was for this ‘train d’assaut’. His patent filings were technical in nature and showed a degree of engineering mechanical competency, so it is fair to assume that Jacquet at least had a degree of engineering knowledge. When it comes to the ‘train d’assaut’, there are not many clues from which to work for providing additional background on Jacquet, not even his address at the time. However, this was disclosed in the 1922 application in Great Britain for a patent on his reversible motor pump. At that time, he was living at 20 Boulevard de Villiers, Levallois-Perret, right in the heart of Paris. Today, this is a rather anonymous and mundane white apartment block with commercial premises underneath. Where Jacquet may have resided 22 years later is unknown, nor is the reason for the hiatus from 1922 to his next patent in 1943.

A French ancestry site (geneanet.co.fr), which cannot be verified, shows a trace of a Victor-Barthelmy Jacquet born in Montbrison, west of the city of Lyon on 6th December 1883 and dying in Paris on 7th May 1947, aged 67. If that entry is correct, then Jacquet was born as one of 11 children and had served in WW1 (1914-1919). He would have been 31 years old at the outbreak of WW1, and 39 when he submitted that first patent. At the outbreak of WW2, in 1939, he would have been too old for military service at 56 years of age and in 1944, when he submitted this assault train idea, 61.

He is certainly not to be confused with Victor Eugene Alexandre Jacquet from Montbrisson, born two years later (1885) and who died in 1946. That Jacquet was a poet and may have been a relative or just someone sharing a similar name, it is unclear which. If geneanet.co.fr has the correct Victor-Barthelmey Jacquet, then this Victor Eugene Jacquet is not a sibling.

Design

The design of Jacquet’s assault train was simple and complex, all in one package. Simple in theory and complicated in design. The fact that this was as far as it went belied the fact that to put such a vehicle into use would border on the fiendishly complex. Consisting of 3 distinct and different sections, known as ‘cabins’, the design connected all three of them together with a hydraulic coupling allowing for independent movement. In total, this vehicle would amount to some 6 to 7 meters long, with around 0.5 m of ground clearance. Using hydraulic pressure, the coupling could also be locked to assist in obstacle crossing. Each section had its own independent track system and turret.

Jacquet’s assault train, as seen in his 1944 patent application, climbing a short escarpment. The image has been digitally cleaned for clarity.
Source: French patent FR99201

The unusual shape of all three cabins left the leading section angled down and forwards, rather akin to the shape of the bonnet on a car. All three cabins were vertically sided with a rounded upper hull. The turret on cabin 1, mounted in the center of this part of the vehicle, could, therefore cover a very shallow angle to the front – ideal for spraying fire into the steep angle of a trench or for when this leading cabin cleared a slope. It also allowed for the turret on the larger and longer cabin in the middle to overlook the entirety of cabin 1, including its turret, meaning it could also fire to the front as well as to the sides. The third cabin, in the rear, was, like cabin 1, small and angled with a turret operating canted. The angle of the hull roof slope was not as sharp as that on cabin 1. Cabin 3 was also slightly larger than cabin 1 as well. All three turrets followed the same shape.

Harder to tell from the side image was that the leading cabin was also narrower than the main cabin in the middle. This allowed for weapons mounted in the leading edges of this central cabin to fire past the forward cabin.

Front view of Jacquet’s Assault Train. No armament shown in the foremost turret. Modified and adapted from French patent FR99201.

Suspension

All three cabins were tracked, using a relatively straightforward system consisting of a large drive sprocket and a toothed idler at opposite ends of the track. Between these large wheels were what appears to be four double sets of wheels connected together in pairs on either side of a heavy inverted elliptical spring, allowing vertical movement of the bogies. Each bogie was effectively split in two, with one wheel-pair in each piece and the two pieces connected together via a pin, allowing the wheel pairs to move slightly independently of each other. The inner of those two-wheel pairs, consisting of the inner half of each bogie, was connected by another set of leaf springs. To add to the suspension provided by those two sets of elliptical springs, a third set, consisting of half-elliptical springs, was fixed firmly at the top to the hull side and flexibly at the bottom to the foremost wheel on the foremost bogie. The rearmost end of the rearmost bogie was affixed to the hull via a vertical arm and, thus, the entire system could move as one, individually or as bogies. Whilst that is simple enough, albeit far from modern for a tank in 1944 which could be on a more modern system, like volute springs or torsion bars, it was still viable.

The suspension system for each of the cabins of the Assault Train. Note that the tracks are facing left to right. Modified and adapted from French patent FR99201.

Automotive

The center cabin carried the engine and primary gearbox for the vehicle, ensuring that the heaviest mechanical components were mounted close to the center of gravity. From there was a rather complicated system of secondary drive elements to carry power from this primary gearbox to the drive sprockets at the back of the center cabin and, via a long drive shaft, to a powered differential at the rear of the rearmost cabin. Although not shown in the plan view drawing in the patient, the output from the gearbox also went forwards down the center line of the vehicle to the front cabin, to presumably another powered differential at the front of the tracks.

Plan view of the main cabin (right) and the smaller fore or aft cabin (left). The image has been digitally cleaned for clarity. Source: French patent FR99201
Seating position for the crew in the center cabin of the vehicle is shown along with the steering levers. The image has been digitally cleaned for clarity. Source: French patent FR99201

Steering for the vehicle was delivered by means of levers and pedals for braking the tracks, accelerating the engine, and also controlling the hydraulics for moving the cabins in what must have been the most complicated driving job imaginable. This would be made worse by the fact that the driver was positioned high up centrally in the middle section of the vehicle, using the turret for visibility. This meant his view forwards on the ground would be totally obscured by the leading cabin.

Armament and Protection

Protection for all three cabins of the vehicle was provided by a body that was well rounded and made from cast type of steel of either manganese steel or another suitable alloy. Inside this cast steel shell would be the necessary supports, pre-made for the attachment of all of the mechanical components, such as the engine and transmission.

Weapons for the assault train are unnamed but, in his patent application, Jacquet describes how the cast steel body would come with supports cast to hold various components and weapons and any “.. liquids, gases, compressed air, etc., necessary for …. The defense of the assault train”. Whilst some of those elements may also form parts of the propulsion or fuel system, there is clearly also the potential envisaged for at least the use of hazardous liquids and gases for defensive purposes, effectively meaning either something corrosive, poisonous, and/or flammable.

To add to the burden and the otherwise difficult working position of the driver, he would also find himself sat alongside the primary armament of the cabin, which was fitted in the turret.

The rear cabin was designed to house a single 75 mm gun which, very oddly, was pointed directly backward out of the hull of the cabin rather than in the turret. Aiming the gun would therefore be a function of aiming the entire rear of the vehicle at the target. The patent further elaborated on armament by suggesting that other anti-tank guns, machine guns, or a “compressed air mine tube against anti-tank barriers” could be added, without providing any conception as to what that weapon might look like.

As a basic outline of the armament spread across the three cabins and turrets, there would be 4 machine guns and 2 cannons and the drawing clearly shows at least two of those machine guns protruding from the forward face of the central cabin. It is logical to assume that some armament would be mounted in each turret. Given that the leading cabin had the turret so sharply canted, there seems little point in a large cannon in that turret, being so limited in use. A reasonable estimate, therefore, of armament might be for just a single machine gun in that leading cabin’s turret, two in the sides of cabin 2, and a single machine gun in the turret of cabin 3, making 4 in total. With a large caliber gun presumably for firing high explosive shells, like the French 75 mm, in the rear of cabin 3, this would only leave the turret in cabin 2 to find a suitable armament for. Given the small size of the turret and the fact that the driver is also sharing it, whatever cannon or other armament mounted therein would have to be fairly small and would serve to complicate both driving and firing.

Crew

No specific crew is listed or detailed by Jacquet but, based on his drawings and description, an estimate can be made. Only one man was needed to drive the vehicle (cabin 2) along presumably with a commander – again, best positioned in the turret of cabin 2, and therefore probably having to operate the gun as well. At least one other crewman would be needed in cabin 2 to operate the hull machine guns on one side and two men if both were to be operated at the same time, for a total of 3-4 men (commander, driver, machine gunner x 2) in cabin 2.

Cabin 1, with no driving to do, would need at least one man to operate the gun and possibly a second to assist with loading or observation (machine gunner, assistant). The same is true in the rearmost cabin (cabin 3), with the added complexity of the large field gun which would need at least two men to operate so that it could be loaded, aimed, and fired with any degree of alacrity. That would mean not less than 3 and more likely 4 men (turret machine gunner, field gunner, two loaders) there. This means that across the three cabins, at least 8 and maybe as many as 10 men would be needed to operate the entire vehicle.

Articulation

This was certainly not the first articulated fighting vehicle concert. The first of the modern era was from British Colonel R. E. B. Crompton in 1915, with two tractors connected back to back in an effort to make a longer tracked vehicle for crossing trenches. It is this obstacle crossing ability which was, and still is, appealing to designers of articulated vehicles, like the plan for a set of additional tracks on the front of the St. Chamond in WW1, Delahaye’s 1918 design for a multi-tracked articulating vehicle, or the design for connecting a whole series of tanks together from M. Boireaux in 1936. They all used this characteristic to dramatically move one set of tracks from the other to increase the mobility of the vehicle over rough terrain or obstacles.

It is not known if Jacquet knew of some or any of these preceding ideas or not or if this was just a case of convergent thinking. Either way, the outcome was the same – using a system of articulation of one or more sections of track, whether independent on a chassis or not, to increase obstacle crossing.

The means by which Jacquet’s vehicle was to cross an obstacle was, much like the other ideas, to use one or more sets of tracks on a body or bodies. For Jacquet, in his three-cabin vehicle, it was the smaller leading cabin that led the way in crossing obstacles and this was achieved with a hydraulically controlled bearing between the cabins, which allowed for both vertical and horizontal movement. Cabin 2, the larger of the three cabins and located in the middle, provided the bulk of the system, with the third cabin at the back acting almost as a tail and balance for the whole lot. Between the cabins were effectively spheres, with a third of the front and rear removed and with the remaining part able to fit into the adjoining piece, giving the appearance of a concertina effect when in operation. For the connection between cabins 1 and 2, this was formed from three such ‘cut spheres’ forming the connection, but only two for the connection between cabins 2 and 3.

The three cabins of Jacquet’s Assault Train seen from above, showing the horizontal movement available to it. Note that the image has been digitally cleaned for clarity.
Source: French patent FR99201

When the system came to a vertical obstacle, such as a wall or even a cliff up to the height of the whole vehicle, it would begin to scale it by elevating the leading cabin hydraulically. Lifting this off the ground and then moving cabins 2 and 3 forwards would push cabin 1 up the cliff. As cabin 1 got to the top, the middle cabin would come off the ground but be hauled forwards by the trailing cabin, helping to provide forward thrust, as well as what traction cabin 1 could purchase at the top of the escarpment. As cabin 1 cleared the top, this tractive effort increased and brought cabin 2 to the top just as cabin 3 started to leave the ground and provided less and less traction.

Diagrammatic cross-section of the leading section of the vehicle, showing the engine and primary gearbox, along with the circles indicating the articulation. The rounded body work is also apparent. Note that the image has been digitally cleaned for clarity.
Source: French patent FR99201

Thus, all the pieces of the vehicle would act in sympathy with each other. As one piece lost traction, the others gained it, balancing out the forces needed. Even in the case of a vertical face, the system could work on paper.

The means by which the tank could climb a sheer cliff face as tall as itself.
Images adapted and modified from French Patent FR907544.

In the case of a wide gap, such as a particularly unpleasant anti-tank ditch, river, or canal, the system still worked. However, instead of elevating the leading cabin of the vehicle, the coupling could be locked and cabin 1 pushed ahead into the gap. As long as the center of gravity of the vehicle was not exceeded in pushing this leading cabin out in the void, the whole train would remain level on the other side of the gap. By the time cabin 1 reached the other side, cabin 2 would be exiting the bank, and cabin 1 would be pulling it across and so on for cabin 2 and cabin 3, with the coupling locked. Assuming that the gap allowed for a small dip onto the facing bank, like crossing a river, then the gap crossable could be even larger than that of the distance to the center of gravity. This relatively small vehicle of three parts possessed a remarkable level of agility which would set it apart from a more conventional design.

Original page from Jacquet’s patent.

Conclusion

Jacquet’s Assault Train swerved headlong into oblivion as a design. Once the basic elements were drawn as they were, Jacquet had committed the vehicle to an impossibly complex drive and hydraulic system to navigate even relatively modest obstacles. Hard to drive, complex to maintain, impossible to command to any effect, the vehicle rightly was as poorly thought-out as it was likely for production or adoption.

Many of the same problems with articulated vehicles which existed prior to this design and which continued to exist thereafter, such as control over the separate sections of the vehicle, how to command and operate it, how to effectively lock and release a hydraulically actuated flexible coupling, were unresolved. Jacquet’s solutions were just like his suspension design – simple in thought, complex in practicality and worse than every other available alternative. There was absolutely no likelihood of this design reaching any stage of trials or production with an armed force as it was laid out. If the technical issues were not bad enough, then the ludicrous number of crew required to operate it should be sufficient to kill it off. A vehicle needing 8 to 10 or more crew was simply never going to be a viable concept when contemporary vehicles fielded by Britain, France, the USA, and the Soviet Union, were 4 and 5 man crews for substantially more tank for the effort.

A slight ray of light for the vehicle was the basic concept of articulation. Whilst it was certainly not new at the time, it was at least clear on how an articulated vehicle of more than 2 sections could have an advantage over a 2 piece design. Namely, a three-piece vehicle could climb even higher obstacles or cross even greater gaps using that third cabin at the back as a tail. Nonetheless, the patent was accepted in July 1951 and quickly filed and forgotten.

5-way vies of the Jacquet Assault Train, showing off the articulated design and the odd turrets.
Front-right view of the Jacquet Assault Train cresting a rise. The advantages of the articulated design are evident.
The same from the rear. All renders done by Giganaut, funded by our Patreon campaign.

Specifications – Jacquet’s Assault Train

Crew: est. 8 – 10 men (driver, commander, machine gunners x 4, artillery gunner, loaders x 2)
Dimensions: 6 – 7 metres long. 0.5 m ground clearance.
Armor: cast steel or manganese or other alloy cast armour
Armament: Optional single 75 mm cannon, anti-tank guns, multiple machine guns, compressed air explosive launcher

References

French Patent FR545918 Moteur rotatif reversible, filed 14th January 1922, granted 4th August 1922, published 4th October 1922
British Patent GB191718 Reversible Rotary Motor or Pump, filed 29th December 1922 – application not accepted.
French Patent FR887564 Dispositif Differential, filed 6th November 1942, granted 16th August 1943, published 17th November 1943
French Patent FR897490 Disposif de changement de vitesse, filed 24th August 1943, granted 30th May 1944, published 22nd March 1945
French Patent FR90371 Machine rotative, filed 6th June 1944, granted 10th September 1945, published 8th April 1946
French Patent FR906066 Motor-thermique, filed 25th July 1944, granted 7th May 1945, published 21st December 1945
French Patent FR99201 Train d’assaut, filed 25th September 1944, granted 18th July 1951, published 24th October 1951
French Patent FR907544 Disposif de transport a patins et roues commandees, field 31st October 1944, granted 2nd July 1945, published 14th March 1946
Forehistoire.free.fr http://forezhistoire.free.fr/56-ph-victor-jacquet.html

Categories
WW2 German Heavy Prototypes WW2 Soviet Prototypes

Grote’s 1,000 tonne Festungs Panzer ‘Fortress Tank’

German Tanks Soviet Union/Germany (1932) Super Heavy Tank – None built

In armored terms, few tanks evoke more awe in terms of size and specifications than the Maus, a 200-tonne behemoth from the tank-stable of the even more famous Dr. Porsche. It is also no secret that there is a certain following, especially online and in the media generally, for what could, at best, be described as ‘Nazi Wonder Weapons’. It is not that any one of these ideas could have won the war for Germany, that was simply not going to happen in 1945 regardless of whatever vehicle, missile, or plane the Germans developed. What they were, however, is a reflection of the giant level of engineering and imagineering which ran amock at times in Nazi Germany. A political mindset wanting a 1,000 year Reich was also thinking huge in every conceivable area, from giant planes to super-ships, rockets, and, of course, tanks. If the Maus impressed as a 200-tonne vehicle, then imagine a vehicle 5-times that weight; a true goliath.

Online, that vehicle has become known as the ‘Ratte’ (Eng: Rat), as some kind of allusion to its Maus-sized forebear, but the vehicle was less rat-sized and more landship-sized and was known under the less amusing name of ‘P.1000’. Perhaps even more surprising than its incredible weight and size was that this vehicle was not some late-war attempt to wrestle victory from defeat by overwhelming Allied superiority, but began life in the 1930s. More than that, it did not even begin life in Germany, but in the nation to become Nazi Germany’s greatest enemy, the Soviet Union.

The Men Behind the Tank

The primary figure in the story of the P.1000 is the enigmatic Edward F. Grote. (Note that his name is repeated numerous times online and in books as ‘Grotte’, but is very clearly written as Grote with one ‘t’ in both British and German patents, so his name assuredly was ‘Grote’). Grote’s work on huge tanks had begun early during the time he spent working in the Soviet Union (USSR). A skilled engineer, Grote had lived in Leipzig between 1920 and 1922, running an engineering concern where he had received several patents for engines, in particular diesel engine innovations. These included methods of cooling and also lubricating those engines with oil under pressure. Grote’s interest in power transfer and diesel engines would be very useful when it came to designing large and heavy tanks.

The Soviets

The Soviets had, after April 1929, tried to emulate the French FCM Char 2C with a project of their own. They had tried to engage foreign engineers and designers and were interested in the ideas of Edward Grote. Grote’s skills led him, by 1931, to become head of the Soviet design team for this new giant tank, his firm having been selected over two rival firms in 1930, primarily for political reasons – Grote was a sympathizer of the Soviet government and one of his engineers was a member of the German Communist Party. His task for the Soviets was to develop a breakthrough tank able to match the French FCM Char 2C and the order for this work was dated 5th April 1930. At the time, the specifications for this breakthrough vehicle were perhaps somewhat unremarkable, with a weight of just 40 tonnes and armor not less than 20 mm thick.

A design bureau known as AWO-5 was set up in Leningrad (now St. Petersburg) for him to conduct this work. By 22nd April 1930, just over two weeks since the task was officially set, the preliminary outline was ready. This design became the first in a series of ‘TG’ tanks – TG for ‘Tank Grote’.

Photo of the staff of the Leningrad design bureau AWO-5, taken in 1931. Edward Grote sits in the centre on the front row. Source: Frohlich


The Soviet TG or TG-1 tank was designed with the involvement of Edward Grote.

In just over a year, the first prototype was ready for trials, but the novel track design was a particularly weak point of the design. Added to this was that the cost was excessive, to the extent that the BT-5, an 11.5-tonne tank with an armor of just 23 mm at best, was preferred instead – hardly suitable for a breakthrough role, although its speed would be useful for exploitation of a breakthrough.

Soviet BT-5 tank (with tracks removed) at Kubinka, Russia.
Source: Craig Moore

More versions of the TG followed and it inevitably grew larger, heavier and more complex in doing so, with the sixth and final version presented in May 1932. By this time, the Soviets had seemingly grown weary of a project which was producing increasingly large and expensive tanks when there were alternatives available, such as emulating the British A1E1 Independent.
The result was that the Soviets turned from this German design to their own vehicle inspired by the British A1E1 and which was ready in 1933, in the form of the T-35A. At over 45 tonnes, this tank was large – nearly 10 m long, and was fitted with 5 turrets, although armor was just 30 mm at best.

Soviet T-35A
Source: Wiki

The First Fortress Tank

Grote, however, had not given up on his increasingly large tank ideas. It is worth noting that the big size limiter for tanks is based around the size and weight which can be borne by roads, and especially railways. These limitations restrict the maximum width and height of the vehicle more than the length. This has historically resulted in some very long vehicles, as the designers of the vehicles struggle to provide the armor and automotive power within these strict limits.

Grote, and several designers before and since, have understood that, as soon as you step beyond these maximums, there is no point in a vehicle a little wider or a bit taller than could be carried by train. Indeed, the decision to go big from a design point of view is technically very freeing, as the dimensions can be made whatever they need to be to fulfill the role of the vehicle. If, like it was for Grote, the need was for a well-protected breakthrough tank with a lot of firepower, then freeing himself from those strict limits meant he could make a big tank to mount big guns. It would need a big engine or engines to power it but, again, there was effectively no limit on the volume into which the unit or units required to power the vehicle could fit.

Liberated from the width and height restrictions of the rail gauge, Grote had gone beyond the plausibility of his TG vehicles and, in March 1933, submitted a new, massive, and less plausible vehicle concept to Soviet Marshal Mikhail Tukhachevsky. Tukhachevsky was a key figure in Soviet military modernization in the 1930s before he, like millions of others, fell victim to the murderous purges of Joseph Stalin. The dimensions of the vehicle were truly staggering. A hull 34 meters long, 10 meters wide, and 11 meters high, it was topped with a pair of 305 mm guns in fully rotating turrets. A pair of smaller turrets, each fitted with a pair of 152 mm guns, were mounted on the front corners of the hull, and two more turrets, each fitted with a pair of 76 mm guns, were fitted aft of the primary turrets. If that was not enough firepower, two further turrets, each fitted with a 45 mm gun, were also to be mounted.

The sides of the hull were vertical and used heavy armor plating 250 mm thick to cover the enormous road wheels* and suspension. The front of the tank was very well angled and was to be 300 mm thick. This 300 mm of armor was to be repeated on the front of the primary turrets and roof armor was to be 100 mm thick. Certainly, this would have been sorely needed given the size of the tank and what a target it would have made for enemy artillery or aircraft. The thinnest part of the armor was the hull floor, at 60 mm thick.

Supported on a trio of 1 m wide tracks on each side, there would be 6 m of track width on the ground. Given that the vehicle was estimated to weigh 1,000 tonnes, this track, with a ground contact length of 20 m, spread the great load and the ground pressure was calculated to be just 0.72 kg/cm2 (about half that of the 180 tonnes Pz.Kpfw. Maus), a little more than that exerted by a heavily laden man’s foot. This was truly the Festungs panzer or ‘Fortress’ type tank Grote was picturing, with a crew of not less than 40 men to command, drive, maintain and operate all of the weapons, but it was also no slouch despite its huge mass.

(* assuming the 1942 rebirth was just a revamped version of his 1933 idea, then the wheels would be around 2.5 m in diameter)

By virtue of twelve 2,000 hp 16-cylinder diesel engines (24,000 hp / 17,630 kW total) and a special hydraulic transmission, Grote expected his 1,000 tonne monster to manage up to 60 km/h. One of the crucial advantages the enormous size would give Grote would be the obstacle-crossing ability of the tank. With its high leading edge of track, his tank would be able to climb a vertical step no less than 4.8 m high and ford an 8 m deep river without having to concern itself with bridges.

With the design submitted, it was reviewed and found to have serious problems. Not the least of these was that the planned engine power and speed of the vehicle were not realistic. There was simply no engine producing 2,000 hp available. The V-16 (cylinders at a 50-degree angle) 88.51 liter Mercedes-Benz MB502 marine diesel engines, could, at best, produce just 1,320 hp at 1,650 rpm or a continuous output of 900 hp at 1,500 rpm. Assuming 12 of those could be used, then this would produce a continuous 10,800 hp or a maximum of 15,840 hp, well short of the 24,000 hp needed. The engines were to have been laid out 6 on each side and all driving a common driveshaft. This power was then to be transmitted either hydraulically or electrically to the drive sprocket.

Mercedes-Benz MB-502 V-16 diesel engine.
Source: Pearce

A supercharged version of that engine was also available later, but this was not in production when Grote’s design was submitted. That engine, the MB-512, could produce the same continuous 900 hp as the MB-502 at 1,500 rpm, but an improved 1,600 hp maximum output at 1,650 rpm. Even if this improved version was available to Grote, it would, at best, have delivered just 19,200 hp combined maximum – just 80% of what he needed.

With no suitable engine available, the Soviets could not accept Grote’s design and would soon part company with Grote and embark on their own fortress-tank work. With the failure of the TG tanks and now this fortress tank, Grote’s work in the Soviet Union came to an end and he returned to Germany in 1933.

Back to Germany

Grote, now living in Berlin, did not stop his engineering and submitted another patent application in 1935. Several more patents followed, relating to transmissions and hydraulic couplings but also, and more importantly, for tracks as well.

Grote’s transmission design of 1936.
Source: British Patent GB457908.

In January 1935, Grote filed a patent application for a novel type of caterpillar track. In his design, half of the metal links of a common style of track were to be replaced by intermediate links made of rubber sandwiched between the steel links. These rubber links would be in compression all the time, squashed between moving metal links on each side. The design would serve not only to create a lighter type of track but also one completely under tension the whole time, which would improve the efficiency of the driving force applied to the track. Perhaps more unusually, none of the links were actually physically connected together in the sense of a track pin. Instead, each track consisted of a pair of flexible chains, rather like the chain on a bicycle or chain saw, which would loop around the drive and road wheels. Each metal link would have two hollow channels made in it for each of these chains to pass through, and then, between each metal link, two of these smaller rubber intermediate links were placed, each with a single channel for the drive chain to pass through. The rectangular shape of the chain and of the channel in both the rubber intermediate links, and the metal links also prevented twisting of the links, or, in the case of the rubber links, any rotation from taking place. As the entire system was in compression the whole time, it also served to provide a completely sealed track system for the chain, so as to keep out dust, which would otherwise increase the wear and tear and reduce the track’s service life. Unlike a continuous rubber belt type track system, where damage means having to replace the whole length of track, this idea meant that localized repair was possible.

Grote’s unusual rubber intermediary link track design of 1935.
Source: German Patent DE651648

Another of his patents, submitted in 1936, was for a moveable caterpillar track system. In that invention, the leading edge of the track could be changed so as to be low during road movement or raised to climb obstacles. There is no mention of tank design in either the metal-rubber-metal track design patent or in the elevated track patent, so it might be assumed that there was no military element involved in his designs.

Grote’s tracked vehicle patent of June 1936, showing how the leading wheel of the track could be raised to improve obstacle crossing.
Source: German Patent DE632293.

Arguments with Burstyn

With some tank-related patents behind him, Grote saw himself referenced indirectly in a December 1936 magazine article that had stated that a German engineer had designed a 1,000-tonne tank for the Soviets. Grote chose to write his own piece in response defending the size of the vehicle he had designed and this appeared in the Kraftfahrkampftruppe magazine in 1937.

In doing so, Grote had managed to earn the ire of Günther Burstyn, the same Günther Burstyn who designed a tracked vehicle in 1912 and had tried, unsuccessfully, to get interest from the Austro-Hungarian Empire in the idea. Burstyn was scathing in his own views on Grote’s concept, saying it was not only impractical due to its size, but also had no military utility, perhaps forgetting how naïve and impractical his own idea had been.

Sporting no less than seven turrets, Grote’s 1,000 tonne Panzer, as it appeared in Kraftfahrkampftruppe magazine in September 1937. Note that Grote’s name in the bottom right corner is clearly ‘Grote’ and not ‘Grotte’. Note also that there are 6 sets road wheels shown.
Source: Frohlich.
The same type of artist’s view as that in Kraftfahrkampftruppe magazine but with a different arrangement of turrets, wheels, mud chutes, and gawking onlookers. Note that there are 9 sets of road wheels shown.
Source: yandex.ru
The size of the figures next to Grote’s idea really illustrates the gigantic proportions he was thinking in.
Source: Frohlich
Another view of Grote’s vision of a giant multi-turreted, 6-tracked behemoth. Note that the central tracks of each trio is clearly recessed from the outer and inner track on each side. It is unclear if that was a deliberate part of the design or if it is a misunderstanding by the artist. Source: Frohlich

Burstyn’s primary complaint was the weight of the vehicle based on the false assumption that more mass meant it would be immobile. The ground pressure for such a massive machine was not particularly great, as it was to have 6 sets of tracks, with each putting around 20 meters of track on the ground. With each track 1 meter wide, 6 of them, with 20 meters of length meant a track contact area of 120 m2 (20 m x 6.0 m) and producing a ground pressure of 0.72 kg/cm2, very low for a vehicle of its dimensions. For reference, the German Pz.Kpfw. VI Tiger produced around 1.04 kg/cm2

Further to this, Burstyn was also critical of the top speed. The desired top speed of 60 km/h was not possible with the engines available at the time but Burstyn did not claim it was impractical for that reason, instead, it appears to be based on the notion that big equals slow. Certainly, 60 km/h was not going to be possible even under the best of situations, as the engines required were lacking, but even assuming he could manage half of the required engine power, it is fair to assume Grote’s design would at least have matched the comparatively slug-like 15 km/h top speed of the French FCM Char 2C. Further, the role such a gigantic vehicle would have to perform in smashing enemy lines, positions, and formations, and high speeds would not be needed anyway. It could not go so fast as to outstrip accompanying and supporting vehicles and troops anyway.

Unlike the FCM Char 2C, Grote’s Fortress tank concept would not use multiple small road wheels but would, instead, use several (the exact number varies in the artist’s impressions) very large diameter (~2 – 3 m) double road wheels per track section. Each of these sets of wheels was mounted into a bogie and that bogie was sprung by means of hydraulic cylinders with a compensator of some type. Steering would be produced by simply braking one side of the tank.

On the matter of immobility, Burstyn was simply incorrect and working on an incorrect premise. He was not, however, wrong in his critique of the military utility of the vehicle, but Grote would have a long way to go before he could prove or promote his ideas again.

Conclusion

The 1933 concept was the culmination of tank work in the Soviet Union, where the tank had got bigger and bigger to accommodate more and more armor and firepower and the larger and larger engines needed to propel the machine. Trying to achieve the goals of heavy armor impervious to enemy fire, heavy armament, and high mobility seem impossible at first glance, especially given the inherent constraints on the size of a vehicle. As Grote would find, the only way to achieve everything he wanted was to step out of the physical limits imposed by things outside of tank design, such as road widths, bridging, and rail gauges. Once those limits were exceeded even slightly, there was suddenly no real limit on the size of the machine and he could start with huge amounts of firepower and massive sections of armor. In doing so, he also would need a means of propulsion which was not available to him at the time. The ‘1,000 tonnes’ was probably as a symbolic weight that might grab the attention or funding which an ‘872 tonne’ design might not, but Grote had embarked on a slippery slope with no limits imposed. The end result was a gargantuan machine which, whether or not it would even move, was irrelevant to what practical use it could possibly have had.

Untethered from the reality, limits on size the machine had grown perhaps way beyond what he had wanted, to a vehicle of huge proportions with a ludicrous array of armament. Grote’s design, quite rightly, was rejected by the Soviets, for whom a simpler and more conventional machine, well armored and armed, would find favor well after the T-35A.

It is perhaps ironic that the lessons learned by the Soviets from this German flight of fancy had to be relearned by the Germans a few years later. Grote, in fact, went on to further refine his ideas. During that development, the dimensions were still gargantuan for a tracked armored fighting vehicle, but the design did at least get a little less ridiculous as it went on, at least in terms of fewer turrets. The weight and armament of those designs, however, remained excessively large and they were equally unsuccessful.

The shorter version of the 1000 tonne Festungs Panzer, showing the completely unworkable layout of the vehicle. Illustration by Andrei ‘Octo10’ Kirushkin, funded by our Patreon campaign.

Sources

Pearce, W. (2017). Mercedes-Benz 500 Series Diesel Marine Engines.
Pearce, W. (2017). MAN Double-Acting Diesel Marine Engines.
Frohlich, M. (2016). Uberschwere Panzerprojekte. Motorbuch Verlag, Germany.
CIOS report XXVI-13. Reich Ministry or Armaments and War Production. Section 16: Interview with Speer and Saur.
German Patent DE385516, Im Zweitakt arbeitende Verbrennungskraftmaschine, filed 25th April 1920, granted 24th November 1923.
German Patent DE370179, Verbrennungskraftmaschine, filed 25th April 1920, granted 27th February 1923.
German Patent DE344184, Zweitaktverpuffungsmotor mit Kolbenaufsatz, filed 4th June 1920, granted 21st November 1921.
German Patent DE370180, Verfahren fuer Gleichdruckmotoren, filed 26th October 1920, granted 27th February 1923.
German Patent DE370178, Verbrennungskraftmaschine, filed 7th January 1921, granted 27th February 1923.
German Patent DE373330, Schwinglagerung fuer Kolbenbolzen, filed 5th May 1922, granted 10th April 1923.
German Patent DE391884, Vorrichtung zur zentralen Schmierung von Maschinenteilen an Kraftmaschinen, filed 18th June 1922, granted 12th March 1924.
German Patent DE741751, Stopfbuechsenlose Druckmittelueberleitung von einem feststehenden in einen umlaufenden Teil, filed 6th January 1935, granted 17th November 1943.
German Patent DE636428, Stuetzrollenanordnung an Gleiskettenfahrzeugen, filed 6th January 1935, granted 8th October 1936.
German Patent DE686130, Geschwindigkeitswechselgetriebe, filed 6th January 1935, granted 3rd January 1940.
German Patent DE710437, Stopfbuechsenlose Druckmittelueberleitung von einem feststehenden in einen umlaufenden Teil, field 6th January 1935, granted 13th September 1941.
German Patent DE651648, Gleiskette mit Zugketten und einzelnen Metallgliedern, filed 6th January 1935, granted 16th October 1937.
British Patent GB457908, Improvements in and relating to Change-Speed Gears, filed 5th February 1936, granted 8th December 1936
US Patent US2169639, Clutch mechanism for change-speed gears, filed 20th May 1936, granted 5th January 1935
German Patent DE632293, Gleiskettenfahrzeug, field 11th June 1936, granted 6th July 1936.
French Patent FR817411, Dispositif de transmission d’un fluide sous pression, filed 5th February 1937, granted 2nd September 1937
German Patent DE698945, Kugelgelenkige Verbindung zweier mit gleicher Winkelgeschwindigkeit umlaufender Wellen mittels in Gehaeusen der Wellen laengs verschiebbarer Gelenkbolzen, filed 31st March 1937, granted 20th November 1940.
German Patent DE159183, Druckmittelüberleitung von einem feststehenden in einen umlaufenden Teil, field 14th March 1938, granted 25th June 1940.
German Patent DE159429, Druckmittelüberleitung zwischen zwei gegeneinander umlaufenden Systemen, filed 14th May 1938, granted 26th August 1940.
Belgian Patent BE502775, Einrichtung zur Befestigung eines Bolzens in einem Werkstueck, filed 25th April 1950, granted 15th May 1951.
German Patent DE842728, Einrichtung zur Befestigung eines Bolzens in einem Werkstueck, filed 28th April 1950, granted 30th June 1952.
Navweaps.com 28cm/52 (11”) SK C/28
Navweaps.com 28cm/54.5 (11”) SK C/34
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Grote’s 1,000 tonne ‘Festungs Panzer’ concept, March 1933 specifications

Dimensions 34 m Long x 10 m Wide x 11 m High
Total weight, battle ready 1,000 tonnes
Crew 40
Propulsion 12 x 2,000 hp
Speed (road) 60 km/h desired
Armament 7 turrets;
1 x twin 305 mm, 2 x twin 152 mm, 2 x twin 76 mm, 2 x 45 mm
Armor 300 mm front, 250 mm sides, 100 mm roof, 60 mm floor
For information about abbreviations check the Lexical Index
Categories
Cold War British Prototypes

Cerebos

United Kingdom (1956)
Heavy Tank Destroyer – Design only

Cerebos was a project designed by the 7th Tank Technical Officers (T.T.O.) Mechanical and Gunnery AFV design exercise held at the British Royal Armoured Corp (R.A.C.) School of Tank Technology (S.T.T.) in 1956. In the study, the designers were tasked with coming up with a heavy tank destroyer using guided anti-tank missiles as its primary offensive weapon. It had to be able to operate on the front lines of a European conflict, have relative immunity from Soviet guns at combat ranges, and a very high chance of scoring a direct hit and killing any Soviet vehicle of the day.

Background

The concept of a heavy and super-heavy missile vehicle had already been on the minds of British AFV designers for a few years during the early part of the Cold War. The Anti-Tank Guided Missile (A.T.G.M.) was a relatively new technology in an era when tank guns were still relying on ranging machine guns for calculating the distance to the target. The ability to effectively engage a tank at twice the effective range of such a gun and to effectively track and guide the missile to the target was highly desirable. This fact, combined with the huge leaps in armor penetration capabilities from shaped-charge (SC) technologies used in High Explosive Anti-Tank (HEAT) type warheads, especially compared to ‘conventional’ anti-tank ammunition of the period, made many think the era of the conventional armored tank was over. This was simply because, using conventional armor technologies, no tank could hope to survive against HEAT warheads such as the French SS.10, Soviet AT-1 Snapper, and later the Mosquito or Swedish Bantam. In order to stop such weapons, steel armor would need to have been over 500 mm thick, which in turn would have led to impractical machines. One result of this technological shift away from conventional armor was a generation of very lightly armored main battle tanks like the German Leopard. Whilst this shift was recognised early in Western nations, despite projects like the British Conqueror and some American heavy tank/tank destroyer projects, it took longer to be recognised in the Soviet Union, at least in the eyes of the West. Tanks like the IS-3 and T-10 loomed large in the imagination and nightmares of Western planners along with some incorrect assessments of the armor of a new generation of Soviet medium tanks. This meant that new means of countering this Soviet armor were needed.

The debate over the end of the tank has been waged since almost the very beginning of the weapon. For each new anti-tank weapon, a new defense innovation was found and, conversely, for each new step-up in armor, a new weapon to defeat this armor was found. In this way, to a broad extent, the evolution of anti-tank weapons very much reflected the evolution of tank armor. Within this context, there are few evolutionary leaps that were as profound in tank terms as this first decade or so after the end of WW2. The A.T.G.M. had gotten to the point where it was closer to forcing the tank into obscurity than ever before and, were it not for the vast fleets of tanks in Soviet service that remained an active threat forcing NATO to maintain its own significant fleet of tanks, armored warfare may have taken a very different route.

In the meantime, all nations were still churning out regular tanks expected to fight other tanks and so, much like the Second World War, tank destroyers were still being developed and built with the sole aim of breaking up enemy tank formations at long range. For the British, the appearance of heavy Soviet armor and the prospect of large enemy armored formations posed a particular threat. Many of those vehicles were virtually immune to the UK’s best tank-guns then in service and in such large numbers that even if they could match Soviet armor with British firepower they could still be overwhelmed.

There was little the British could do to counter the enormous numerical advantage of the Soviet forces in Europe but there was something which could be done about the guns and this fed into the motivation behind the development of the Royal Ordnance L7 105 mm rifled gun and eventually the L1 120 mm rifled gun too. Despite some heavy Anti-Tank concepts in the UK, the 7th T.T.O. Course opted instead for an A.T.G.M.-based Anti-Tank platform over a gun-based solution. The weaponry for this option consisted of a version of the Malkara missile, and this, it was felt, would provide the offensive power required to counter the Soviet threat. It also provided the additional benefit that the avoidance of a turret allowed all available protection to be focussed on the hull instead and all for less weight than a conventionally armed and armored gun-tank.

Cerebos

This was the context and logic behind the Cerebos, a turretless guided-missile tank destroyer with heavy armor. It was intended to operate on the front lines, have enough protection to withstand strikes from enemy tanks using conventional guns, and ideally use the chassis of a vehicle already in service as a platform. It was desired to have a missile able to destroy the heaviest Soviet vehicles then known in service or considered to potentially enter service. An ideal rate of fire of four rounds per minute was requested, with a minimum of two rounds per minute, with two missiles ready to fire at any time.

The model of Cerebos shows a well-shaped front which was heavily armored and the vertical launching pods for the missiles. The missile shown on the ‘stick’ is merely illustrative as they were launched internally and vertically not from this elevated position.

Layout

The goal was to reuse, as far as possible, the hull of an existing vehicle and Cerebos did just that and was based around a heavily modified Centurion tank. This meant a high degree of commonality of parts between Cerebos and the standard battle tank of the British Army of the day, which would reduce the logistical burden of the vehicle. The modifications, though, were extensive. Instead of the sloped glacis of the Centurion, Cerebos used a steeply angled ‘pike’ type nose, similar in style to that on the Soviet IS-3 tank. The driver sat along the centreline of the tank with a forward observation window cut directly out of the armor. The commander sat directly behind him, and the loader sat even further back on a swivel chair that allowed him the freedom of movement to assemble the missiles.

The missile bin had to be as equally protected as the vehicle itself and yet maintain a potential 360° arc of fire. This was somewhat problematic, as adding a conventional missile rack on the top of the vehicle would add not only excessive weight but would also result in a large and conspicuous target that would be vulnerable to small arms fire, shell splinters, etc. It would also be heavy, requiring dedicated hydraulics just to operate. To overcome these issues, the designers had the missile bins located inside the hull of the vehicle in a vertical arrangement, with 5 additional missiles stowed vertically running alongside the left and right sides of the inner hull. On firing the missile, the silo roof would fold open in two triangular parts. The weapon was then fired and guided on to its target by the commander. Once the missile was away, a new one was selected and attached to what amounts to a ‘potter’s wheel’ type base. This base rotated 360 degrees in the missile chamber, with the four fins being added from a separate supply located in front of each missile. This might seem odd as an idea, but the fins were the part of the missile which increased their storage volume and this semi-assembly of the missile attaching the fins meant that a larger number of missiles could be stowed inside the tank.

Protection

Cerebos was based on the Centurion but it was better protected from enemy fire than the Centurion. Sporting heavy frontal armor with a glacis plate 120 mm thick angled back at 65° and a lower front plate 120 mm thick angled at 55°, the Cerebos was felt to be well-enough protected to be able to take any reasonable enemy fire which might be forthcoming from the Soviet tanks of the day. In more conventional UK armor terms, the sides were still quite weak though, with just 25 mm on the upper sides (at 8°) tapering to 20 mm (at 10°) on the lower hull sides. The roof and rear were 25 mm thick, just enough for protection from small arms fire and shell bursts. The belly plate, just 20 mm thick, was sufficient to provide some protection from landmines but the focus of armor was on the front, facing the enemy, making the best use of the weight allowance available for maximum effect.

Automotive

Power for Cerebos was provided by a 9-liter Jaguar 90° V8 petrol engine delivering 350 b.h.p. at 3,750 rpm connected via a Merritt Brown 6-speed (4 forward and 2 reverse) gearbox. Drive was delivered, just like the Centurion – to the rear sprockets. This engine was expected to permit the 21-ton (21.3 tonnes) Cerebos to achieve a top speed of 28 mph (45 km/h) and operate for a maximum range of 220 km at 14 mph (22.5 km/h).

Armament

The primary armament proposed for Cerebos was a Manual Command to Line-Of-Sight (M.C.L.O.S.) type anti-tank missile that looked somewhat like a slightly smaller and sleeker Malkara missile, measuring 5 ft. (1.5 m) long and 10 inches (254 mm) in diameter. Unlike the High Explosive Squash Head (H.E.S.H.) warhead on the Malkara, this 20 lb. (9 kg) warhead was a shaped charge High Explosive Anti-Tank (HEAT) type. The total missile weight was expected to be 85 lb (38.5 kg) and these would be launched vertically from within the missile tube. Once assembled with its fins, it was ready for launching and this could be done whilst a missile was already underway as the targeting was being carried out by the commander with missile assembly taking place independently.

A pair of launchers and 12 missiles (two already assembled and ready to fire, with another ten stowed) could be carried. Although no performance data for these missiles was given, it can be estimated from the diameter of the warhead and the performance of contemporary missiles to achieve a penetration of approximately five times its diameter, which would equal about 750 mm of armor plate – more than sufficient to defeat any known Soviet tank in service at the time.

The maximum range for the missile was just as impressive as the anti-armor performance expected – far exceeding the range available from a conventional tank gun. Cerebos was to be able to engage targets at ranges of up to 6,000 yards (5.4 km), although the missiles did have a minimum safe distance as well – 500 yards (460 meters). With a flight-speed of 350 feet per second (107 m/s), the missiles had a potential maximum flight time of about 50 seconds. For ease of stowage, the missiles were kept without their fins. The gunner would have to assemble the bare missile, attach the fins individually by means of the snap-on fasteners and then load a missile into the missile bin. This whole process was estimated to take not more than 2 minutes per missile. This would mean (assuming two were already loaded) that up to 4 missiles could be fired in a 4-minute window.

Secondary armament for Cerebos was primarily for self-defense and consisted of a single Browning .30 caliber (7.62 mm) machine gun remotely operated from within the hull with a 360° degree arc of fire and provided with 4,250 rounds of ammunition. Six No.36 smoke dischargers were provided, with 3 per-side, and the crew was provided with grenades and small arms.

Side view of Cerebos showing the 5 unassembled fin-less missiles on one side of the compartment. Another 5 were along the right-hand side as well. With two in the bay ready to go, Cerebos had 12 missiles. Note the curvature at the front is unintentional and merely a result of the curvature of the original paper on which the plan was printed and bound.

Conclusion

For its time and era, the wings being clipped on was nothing new and this type of missile-build-before-launch concept was also to be added into the FV4010 heavy missile vehicle, as the later fold out missiles and overall lighter materials were still some years away. Two flaws not raised in the original documentation but more observable with hindsight are the lack of a telescopic mast or periscope allowing firing from the reverse side of slopes and the poorly placed second cupola that had much of its view blocked by being located behind the first. Other issues are the commander acting as the missile gunner, guiding it to its target, placing undue stress, and preventing him from monitoring the battlefield. The Cerebos was no more than a design project and never built, however, many of the ideas and features later appeared on the Malkara launching FV4010.

The Cerebos heavy missile tank destroyer. The vehicle is in travel mode, with the missiles safely within the hull. Notice the very heavily sloped pike-shaped front. Illustration by Yuvnashva Sharma, funded by our Patreon campaign.

Sources
Bovington Tank Museum Archives, STT section, Cerebos box

Cerebos Specifications

Dimensions (L-W-h) 21ft 5.5 inches x 9ft 10 inches x 8ft 4 inches (6.53 x 3.00 x 2.54 m)
Crew 3 (commander/gunner, driver, loader)
Propulsion Jaguar 9 liter 90° V8, 350 bhp
Speed (road) 28 mph (45 km/h)
Ground Clearance 17 inches (0.43 m)
Track Center Distance 8 ft. 4 inches (2.54 m)
Length of Track on Ground 14 ft. 7 inches (4.45 m)
Normal ground pressure 8.4 psi (57.92 kPa)
L/C ratio 1.75
Vertical obstacle crossed 3ft 8 inches (1.12 m)
Gap crossed 7ft (2.13 m)
Armament Manual Command to Line-Of-Sight (MCLOS) ATGM
0.3/7.62 mm MG
Maximum, Minimum Missile Range 6000 yards/5.4 km, 500 yards/457 meters
Missile Velocity 350 fps (107 m/s)
Ammunition 12 High Explosive Anti Tank Missiles
Armor Front: 120 mm @ 65 degrees
Sides: 25-20 mm
Rear 25 mm
Bottom 20 mm