Categories
WW2 German prototypes

Höchammer all-terrain one-man tank

Nazi Germany (1937) One man tank – None built

The machine gun was, and still is, a devastating weapon of war. Able to deliver hundreds or thousands of bullets over a prolonged period of time, a single machine can tie down the advance of thousands of the enemy if it is positioned correctly. The main drawback with the machine gun though is that it is large, heavy, and requires a lot of ammunition. It is no surprise, therefore, that, over the years, there have been numerous attempts to create a vehicle which can carry the machine gun and its ammunition to get close enough to the enemy to deliver on its deadly potential.

Matthäus Höchammer of Fürth, Bayern, had exactly this line of thought in 1937 and submitted his concept for achieving this goal to the German patent office. He was to submit one of the most complex and interesting one-man tank concepts conceived, a vehicle that combined the ultra-low silhouette of a man laid prone with a trench digger and tank tracks combined.

Side view of Höchammer’s design for a one-man tank showing the elevation of the front-mounted blade. Source: German Patent DE665817

Arrangement

The general layout for Höchammer’s design followed the same thought process of other one-man tank designs: a man lying down and controlling the tank with his feet while operating a forward-firing weapon.

Lying the operator prone in the tank created a low-profile for the vehicle. As the hands would be occupied by the weapon, the vehicle would be controlled almost completely by means of foot control for speed and direction and all of this would be clad in armor to protect it from enemy bullets. As such, there are several very similar designs, most notable of which is that of Ernst Mahlkuch, another German designer-submitted patent in 1938.

Lying face forward, the single-occupant was very low to the ground. This enabled him to make good use of cover, both from fire and visual cover, as a low vehicle like this could hide in just long grass. What was an advantage for protection though, was a significant handicap for operations, as it reduced the observation height for the operator, meaning he would find it hard to identify and target the enemy forces and make it difficult to see obstacles in front of the vehicle.

Construction of the design was relatively straightforward, with the lower half of the hull being made from a sheet of pressed steel. The upper half was angular with a pointed front and sharply sloping roofline, both of which would improve ballistic protection by encouraging the deflection of incoming enemy fire. The top half had the appearance of being welded together, made from flat panels of metal. Given its small size would likely be ‘bulletproof’ at best, this would mean around 10-12 mm thick with the lower half being much thinner, as it would be unlikely to have to be protected from enemy fire at all.

The single occupant of Höchammer’s design had to lay prone to keep the height of the vehicle down and had to face forwards in order to see where he was going. This meant that the controls were operated by his feet, keeping his hands free to operate the single machine gun pointing forwards.

As an effort to provide a modicum of comfort to the operator, Höchammer incorporated a mattress for him to lay on, a nice touch to improve the conditions inside an otherwise noisy, cramped, and rather crude weapon.

Automotive

Behind the operator (commander, driver and gunner combined) was the engine, operated by means of pedals pushed by the operator’s legs. The engine was to be of a ‘particularly strong’ type, a high-speed 4 or 6-cylinder engine, although Höchammer made no comment as to whether it would be running on petrol or diesel.

Connected to this engine was the gearbox which delivered power to the final drives for the tank located at the back. Running on thin tracks for the full length of the tank, the suspension was provided for by means of 3 pairs of overlapping wheels with a large wheel at each end of the track run. Track support was provided by means of rollers above the road wheels.

The engine for Höchammer’s design was low, exhausted to the rear, and was cooled by a fan at about a 45 degree angle drawing air through an angled radiator at the back. Source: German Patent DE665817

Trench

Höchammer’s design had a very low ground clearance and this would make it very vulnerable to becoming stuck on a rock or tree stump, not a surprise in a tank just 25-30 cm high. Unlike Malkuch though, Höchammer had a viable solution to this problem, one which further increased the protection of the vehicle from enemy observation and fire – a bulldozer blade. This allowed the vehicle to carved a shallow trench for itself making it harder to see and hit.

Front view of Höchammer’s design with the blade off (left) and blade down (right). The profile it was to cut through the earth is shown in the left image. Source: German Patent DE665817

As the vehicle moved forwards, the bulldozer blade would plough the earth in front of the vehicle, pushing the spoil out to each side. These earthen banks on each side provided additional cover for the vehicle and also meant it was even lower than it would be operating on the surface. If a stiff obstacle was encountered or the blade was not needed, it could simply be retracted upwards above the line-of-fire of the machine gun.

The blade had the additional advantage that it created a shallow trench in which following unarmored troops could crawl through as part of their advance.

Conclusion

Just like other one-man tanks, the one from Matthäus Höchammer was fundamentally flawed. It was so low that the occupant would have a terrible view of the battlefield, very thinly protected, and with all of the fightability, steering, and command of the tank in one man, hard to control too. There is simply too much in a tank as a combat system for one man to manage by himself and it is likely this reason, above all others, to explain why this one-man tank concept went nowhere.

The failure of the design though was not the end of Höchammer. He was a Master Carpenter by trade and survived WW2. His tank design might have been useless but Höchammer at least found some success in life as, between 1952 and 1956, he served as an elected member of the Fürth Block e. V. political movement on Fürth City Council.

The Höchammer one-man tank, showing its insanely low height and the bulldozer blades at the front. Illustration by Andrei “Octo10” Kirushkin and funded by our Patreon campaign.

Sources

German Patent DE665817 ‘Geländegängiger, gepanzerter Einmannkampfwagen’ filed 8th May 1937, granted 15th September 1938
Hrsg. Kreisverband SPD Fürth: 90 Jahre Fürther Sozialdemokratie 1872 – 1962. Eigenverlag Fürth, 1962
Via Fuerth Wiki

Specifications

Dimensions 25-30 cm high, ~50 cm wide
Crew 1
Armament Single machine gun
Armor est. 10-12 mm max
Categories
WW2 German prototypes

15/17 cm Sturmgeschütz auf E100 Fahrgestell

Nazi Germany (1944) Tank Destroyer – None built

The E100, a 100-tonne experimental chassis developed by the firm of Adler using the Krupp 130-tonne Tiger-Maus design, was never finished. Partially complete at the end of the war, it was recovered to the UK for testing and evaluation and the ‘tank’ part of its history has, since the war, remained centred on this aspect of it. The design was a complicated and drawn out process and the use of the hull went further than just a tank concept.

When Krupp’s Tiger-Maus was abandoned in January 1943, the design was surplus, as development effort went into the Porsche-Maus instead. However, Ernst Kniekampf (Panzer Kommission) did not throw out Krupp’s design. Instead, and regardless of whatever reservations he may have expressed later about heavy tanks, he handed off the plans to the firm of Adler by the end of June 1943. Adler then worked on the design, making changes to it but keeping the essential design. The only substantive change, in fact, was the switch from Tiger II-style torsion bar suspension to externally-mounted Belleville-Washer-type spring suspension. Very little, other than collecting parts, took place with the E100 until March 1944, when Krupp became aware of its existence.

Considering it was their original work, they were likely unhappy at having been sidelined on the matter, but they obligingly provided assistance to Adler in the construction of the E100 anyway. When, in May 1944, the opportunity to work on a new vehicle mounting a 15 cm or 17 cm gun came up, there were two hulls optioned for it: the Maus (designed by Porsche and built by Krupp), and the E100 (designed by Krupp, added to by Adler, and to be built by Krupp). Krupp, therefore, embarked on another task, how to fit the huge 15 cm or 17 cm gun onto their as yet unbuilt, and untested E100 chassis.

Conception

If the idea of a 15 cm or 17 cm gun in a fixed casemate on a Maus hull is not hard enough to visualize, then it is worth bearing in mind that mounting a gun of this size on an E100 chassis is even more so. Specifically, because the E100 chassis was so much lighter, under 90 tonnes fully laden for the chassis.

On 9th May 1944, representatives from Porsche and Krupp met to discuss a new heavy type of self-propelled gun. Drawings were presented at this meeting of ideas by Krupp for how to mount the 15 cm L/63 or 17 cm L/53 gun on the Maus chassis as a direct competitor to a similar idea from Adler (Adlerwerke) for mounting these guns on the E100. Both designs were to use a fixed casemate structure (Sturmgeschütz Aufbau) in which to mount the guns.

These ideas were considered at a meeting held at Porsche’s plant on 17th May 1944, and it was here that Krupp expressed their earnest desire to do anything to avoid having to try and use the 15 cm gun in preference to the 17 cm one, likely as a result of the size and weight of the gun and its shells. Obering Hendel, the officer dispatched to ensure production quotas were being met by tank factories, considered both Maus and E100 ideas. His conclusion was not in favor of the Maus. The Maus hull was too high for a new fixed casemate to still fit within the rail loading gauge (assuming a normal railcar), whereas the E100 hull, being significantly lower, was much more suitable.

The Maus-plan was over, it was not a suitable platform and was abandoned as an idea. Instead, the E100 was selected, and on 28th May 1944, Krupp was requested to produce a 1:5th scale wooden model of their design. The purpose of this model was to get a better insight into how the vehicle could be organized internally for crew and ammunition. Importantly, both the 15 cm and 17 cm guns were to be shown, and the design was known as 15/17 cm Kanone auf E100 Fahrgestell (15 or 17 cm gun on 100-tonne experimental chassis).

Development to Termination

Although the E100 chassis had shown more promise, primarily as a result of being lower and lighter than the alternative chassis (Maus), this success was short-lived. Just under two months after being told to produce this model, all work was stopped. Wa Prüf 6 (Waffen Prüfen 6 – the design office responsible for motorized equipment) forwarded to Krupp a copy of the letter from Reichsminister Albert Speer dated 10th July 1944. In the letter, Speer, on Hitler’s orders, required all work on heavy guns on tank chassis to cease. There was a model, however. Krupp must have finished or at least prepared a model by this date as the letter ended that they were to take the model of the Sturmgeschutz 15 cm L/68 to General Guderian.

Guderian was not a fan of these heavy tank projects and had scuppered plans for Maus production a year earlier. There was little-to-no likelihood that he would suddenly change his mind on this type of project seeing just a wooden model of it. Nothing more is heard of the project after this point as it met the same fate as the 15/17 cm Sturmgeschütz auf Mausfahrzeug before it.

Plans for the mounting of the 15 cm gun still survive, at least for mounting it on the front of the turret for E100, but there is no trace of the 1:5th scale wooden model. Nonetheless, it is worthwhile considering what this machine might have looked like, aside from the fantasy creations of model makers and computer game companies, which may be designed more for the ‘cool’ factor than from a basis in engineering.

Layout

The primary consideration over what a 15/17 cm Kanone auf E100 Fahrgestell would look like begins with a look at the E100 hull. As it was was, the E100 hull featured a conventional layout with the engine at the rear, transmission at the front, and a centrally-mounted turret. There were plans for a modified layout on the E100, but as of 1944, when these plans were being considered, these had not progressed, and the original E100 hull had still not been finished. It remains open to question as to whether or not the 15/17 cm Kanone auf E100 Fahrgestell being proposed was to use the first hull or this later modified hull, but as this was future planning it is possible it was to be based off the second, improved hull. Further, it remains open to question as to whether the layout would be fundamentally altered with a casemate placed at the rear with the engine in front of it, like the Elephant/Ferdinand, or if it would simply occupy the space previously filled by the turret and basket.

Regardless of which E100 hull was to be used, the turret, and therefore the casemate, could only be fitted centrally or just forward of centre. Mounting anything else on the already heavy front end, such as in the manner of a Jagdpanther, would simply overwhelm the suspension.

Assuming a central position for the casemate, in roughly the same manner as the Jagdtiger, would mean that no changes would be made to the engine and transmission layout in either hull and keep the front driving position (front left) able to access the main crew compartment. Moving to a rear casemate system would separate the driver from the fighting compartment. A rear casemate would also suffer from the additional problem of having the gun over the engine bay which would greatly complicate access to the engine compartment for maintenance, a serious consideration in the design of the Jadgtiger and a primary reason for adopting a central-casemate layout.

Armor

It is assumed that the basic armor of the E100 hull, including the removable side armor sections, would be maintained and also that the armor on the casemate would approximately match the same protection levels offered by the E100 turm. That turret weighed just 35 tonnes with 200 mm of armor on the front, 80 mm on the sides, and 150 mm on the rear. Being a fixed casemate would mean there would be little scope for manoeuvering to avoid being hit in the sides but, just like the Jagdtiger, which had over 200 mm on the casemate face and 80 mm on the sides, the casemate on a 15/17 cm Kanone auf E100 Fahrgestell would likely be done in a similar way, except that the rear turret armor planned (150 mm thick) would not be required. On the turret, it added a degree of protection to accidental friendly fire from behind but much more importantly, acted as a counterbalance to the enormously heavy front of the turret. No such counterweight was needed on a fixed casemate so the armor could, if so desired, be greatly reduced in that area. Although it makes sense to reduce weight, the rear of the lower rear hull would still be 150 mm thick.

Jagdtiger blueprint
Manufacturing scheme for the Jagdtiger, showing the massive casemate front armor to good effect and a possible approximation of the layout envisaged for mounting a heavy gun on the E100 chassis. Source: Frohlich

Gun

The two guns in consideration for mounting on the E100 chassis were the 17 cm Stu.K. L/53 and the 15 cm Stu.K. L68. The 17 cm gun was, as of 22nd March 1944, still only a paper design and was unlikely to be available anytime soon given the demands of gun production already being very high. The second gun, and by far the preferred option of the two, was the 15 cm Stu.K. L/68 gun and the design for this piece was finished on 4th July 1944, just 6 days before Hitler killed the project.

Fragment of an official German drawing showing the proposed installation of the 15 cm Stu.K. L68 on an E100 chassis. Source: Warspot.ru

Given the enormous size of the 17 cm gun, its huge breech, high weight, and the size of its ammunition and the date of the design for the 15 cm gun, it seems likely that Krupp did everything they could to avoid using the 17 cm gun. Both guns, however, had to meet the requirements set by General Guderian (Inspector-General of Panzer troops) in April 1944 to be able to defeat up to 200 mm of armor at 4,000 meters, leaving no doubt as to a key intended purpose of this vehicle, the destruction of increasingly well-armored enemy tanks at long range. Of note too is that there is no comment as to secondary weaponry. Not a machine gun, but a second, tank cannon, like was originally intended for the Maeuschen program with a 15 cm or 12.8 cm gun paired with a 7.5 cm gun. Only using this single large gun would free up significant space inside the casemate for this E100-based vehicle as well as providing additional stowage space for the 15 cm ammunition. Just as with Maus and E100, it could be expected that a machine gun (either M.G.34 or M.G. 42) would be mounted independently on the left-hand side of the main gun to be operated by the gunner.

One last note on the casemate is the use of a rangefinder. The two rangefinders considered for the Maus II and E100 turm rangefinders were coincidence type devices fitted across the width of the turret. Both types were around 2 m long (1.9 and 2.1 m wide) and there seems to be little doubt that the 15/17 cm Kanone auf E100 Fahrgestell would also have to have a rangefinder, especially given the 4,000 m ranges at which it was going to be expected to deliver accurate fire against enemy tanks and structures. Given the common positioning of the rangefinder on the Maus II and E100, it is reasonable to assume a similar arrangement of a similar size/type of rangefinder would also have to have been used on the 15/17 cm Kanone auf E100 Fahrgestell.

Crew

Regardless of which layout the 15/17 cm Kanone auf E100 Fahrgestell took, it would need a crew and it is hard to envisage this vehicle operating with a crew of fewer than 6. At a minimum, the vehicle would need a driver, a radio operator, a loader, a gunner, and a commander, which totals 5. The Maus required the sixth man in order to operate the secondary 7.5 cm gun, and whilst it was likely that no such gun was to be on the 15/17 cm Kanone auf E100 Fahrgestell, the use of a second loader was all but essential, unless some kind of loader-assist system was planned, considering the size and weight of the 15 cm ammunition. A unitary (one piece) 15 cm shell, for example, weighed in excess of 34 kg and possibly over 40 kg depending on what ammunition might have been chosen. Moving those shells around would rapidly exhaust a single loader, so a second loader is almost essential just to make the machine viable.

Conclusion

Although the idea of the 15 cm or 17 cm gun using the Maus chassis had failed after a brief spark of interest in May 1944, with the E100 being selected in preference, it was not much of a loss. The E100 was to suffer the same fate. On 10th July 1944, Hitler canceled all of the work on these heavy guns on heavy tanks and the 15/17 cm Kanone auf E100 Fahrgestell became yet another failed project in what was a very long list of such projects.

Although it is not known what the 15/17 cm Kanone auf E100 Fahrgestell would have looked like and much of this article has been speculative about the shape and look of the vehicle, it is important to consider the design in order to gain an understanding of the challenges involved in mounting very large guns on very large chassis.

For Germany in mid-1944 to be considering these weapons though was pure folly. It would take months to get such a machine into production and longer still to get crew trained and units issued and deployed to combat. At a time when Germany was on the retreat and the war was a foregone conclusion, to focus precious and ever-dwindling resources on these machines was wasteful. It did nothing more than hasten the end of Germany.


What-if illustration of a Sturmgeschütz auf E100 with a centrally-mounted fighting compartment sporting the 15 cm Stu.K. L/68 gun in a Dunkelgelb finish.


What-if illustration of a Sturmgeschütz auf E100 with a centrally-mounted fighting compartment sporting the 17 cm Stu.K. L/53, lacking the E100 side skirts and with only a layer of Rotbraun primer paint.

Both illustrations by Mr. C.Ryan, paid for through our Patreon campaign.

Specifications

Dimensions (L-W-H) est.39.3 feet x 14.6 feet x 11 feet (12 x 4.48 x 3.37 meters)
Weight est. 127 long tons (130 tonnes)
Crew est. 6 (commander, gunner, 2 x loaders, driver, radio operator)
Propulsion Maybach HL 230 P30 V-12 Petrol delivering 700 hp
Maybach HL 234 V-12 Petrol delivering up to 1,200 hp
Suspension Hortsmann
Speed (road) <23 km/h (road) (HL 230), up to <40 km/h (road) (HL 234)
Armament 17 cm Stu.K. L/53 alternatively 15 cm Stu.K. L68
7.92 mm M.G.34 or M.G. 42 machine gun
Armour Casemate:
Front – est. 200 mm
Sides – 80 mm @ 29/30 deg.
Rear – est. 80 mm
Roof – 40 mm @ 90 deg.
Hull:
Front – Glacis – 200 mm @ 60 deg.
– Lower front – 150 mm @ 50 deg.
Track guards –
Sponson floor – 30 mm @ 89 deg.
Side – 120 mm @ 0 deg.
Rear – 150 mm @ 30 deg.
Floor – front – 80 mm @ 90 deg.
Floor – middle and rear – 40 mm @ 90 deg.
Roof – 40 mm @ 90 deg.
Trench est. 9.5 feet (2.9 m)

Sources

Porsche, F. Bericht Uber die Werksorprobung des Typ 205/1 in Böblingen von 11.1 – 3.2.1944
British Intelligence Objectives Sub-Committee. (1945). BIOS report 1343: German Steel Armour Piercing Projectiles and Theory of Penetration. Technical Information and Documents Unit, London.
British Report on ‘Experimental Super Heavy Tank ‘Mouse’ (Pz.Kpfw. Maus)’ – May 1945
CIOS Final Evaluation Report 153. (28th June 1945). Interrogation of Herr Stiele von Heydekampf.
Datenblatter für Heeres Waffen Fahrzeuge Gerät W127. (1976).
Frohlich, M. (2016). Panzerkampfwagen Maus’. Motorbuch Verlag, Germany
Frohlich, M. (2015). Schwere Panzer der Wehrmacht. Motorbuch Verlag, Germany
Jentz, T., Doyle, H. (2008). Panzer Tracts No.6-3 Schwere Panzerkampfwagen Maus and E 100.
Ludvigsen, K. (2018). Professor Porsche’s Wars. Pen and Sword Publications
Ogorkiewicz, R. (1991). Technology of Tanks. Janes Information Group, Surrey, England
Sawodny, M., Bracher, K. (1978). Panzerkampfwagen Maus und andere deutsche Panzerprojekte. Odzun-Pallas-Verlag, Friedberg, West Germany
Pasholok, Y. (2015). Heavyweight Paper Tank Destroyers at Warspot.ru https://warspot.ru/4351-sverhtyazhyolye-bumazhnye-istrebiteli-tankov
Pasholok, Y. (2016). Heavyweight Paper Tank Destroyers at Warspot.ru https://warspot.ru/5659-bronetehnika-iz-taynyh-podvalov
Spielberger, W. (1998). Spezialpanzerfahrzeuge des Deutschen Heeres. Motor Book Verlag
Spielberger, W., Milson, J. (1973). Elefant and Maus. AFV Weapons Profile No.61.
US Army. (1953). Technical Manual TM9-1985-3 German Explosive Ordnance (Projectiles and Projectile Fuzes)
US Army. (1946). Intelligence Bulletin March 1946. The German Mouse.
US Navy. (September 1945). Technical Report 485-45 – German Powder Composition and Internal Ballistics for Guns. US Naval Technical Mission in Europe Report.
War Office. (25th October 1944). 12.8cm A.Tk. Gun Pak.44 on Pz.Jag. Tiger (Pz.Kpfw. Tiger B Chassis) Sd.Kfz.186 JAGDTIGER. Appendix D War Office Technical Intelligence Summary, No.149 1944.
War Office. (25th April 1945). Technical Intelligence Summary Report 174 Appendix C
War Office. (4th June 1945). Technical Intelligence Summary Report 178 Appendix E
War Office. (27th June 1945). Technical Intelligence Summary Report 180 Appendix D
War Office. (26th July 1945). Technical Intelligence Summary Report 182 Appendix F and G
War Office. (11th October 1945). Technical Intelligence Summary Report 186 Appendix A
War Office. (20th December 1945). Technical Intelligence Summary Report 188 Appendix

Categories
WW2 German prototypes

Durchbruchswagen

ww2 German half-tracks Nazi Germany (1935-39)
Heavy Tank – 3 Hulls & 1 Turret Built

The Tiger I and the Tiger II are some of the most famous tanks in the whole history of armored warfare. These behemoths of World War Two have captured the imagination and attention of many generations of tank lovers and armor researchers. However, while the Tiger was the product of a rushed development following the lessons of Operation Barbarossa, the German quest for a heavy breakthrough tank stretches back to 1935, with the design process of a 30 ton Panzer that would become the Durchbruchswagen.

A Long Incubation

The first mention of what would eventually become the Tiger series appears in a report from October 1935, at a time when Germany had barely started building the Panzer I. General Liese, the head of the Heeres Waffenamt, the German Army Weapons Agency, stated that:

“The initial velocity of the 7.5 cm gun must be increased to about 650 meters/second to be effective against the Char 2 C, 3 C, and D. This type of increase requires the design of a completely new Panzer. Based on rough calculations, armor protection up to 20 mm thick (still not fully protected against 2 cm guns) would result in a weight of at least 30 tonnes. The head of the army recently spoke out against this type of tank. As a follow-up action, confirm that the development of a medium Panzer weighing about 30 tonnes with a 7.5 cm gun with increased capability can be dropped.”

It is notable that a 30 tonne tank was seen as a medium tank at the time, given that the newly built Panzer I weighed just 5 tonnes, while the first versions of the Panzer IV would go on to weigh 18 tonnes. Nonetheless, it is important to note that this tank, armed with a 7.5 cm gun, was intended as a counter to enemy heavy tanks, most notably the French Char 2C and the Char 2C bis, incorrectly called the 3C in the document.

The weight of 30 tonnes was chosen because, as was brought up during a 1936 meeting on the development of an engine for this tank:

“a higher weight would hardly be allowable when considering the Pionier bridging equipment”

The 30 tonne Panzer development project was not dropped by the Army and reappeared in the documentation in December 1935, with the problem of the engine:

“Dipl.Ing. Augustin turned the discussion to the development of a 600 hp engine for the heavy Panzers and noted that his opinion was that 600 horsepower will not be sufficient and that indeed it would be more correct to immediately develop a motor capable of 700 hp.”

This was just wishful thinking. At this point, Maybach was barely testing a 300 hp engine. The planned 600 hp 32 liter Maybach HL 320 V-12 petrol engine never got built. One year later, in October 1936, Wa Pruef 6, the German design office for armored vehicles, sent a request to Krupp for a conceptual design of a turret for this 30 tonne Panzer sporting the 7.5 cm L/24 gun.

Reproduction of the Durchbruchswagen experimental hull based on the description given by Dipl.Ing. Adders, the head of the design department of Henschel, following his interrogation by British Intelligence in 1945. Note that the five road wheels on each side are offset from each other indicating the use of torsion bar suspension. Source: Germany’s Tiger Tanks, D.W. to Tiger I

A Tank With Many Names

At this point, the 30 tonne Panzer was known as the Begleitwagen (verstaerkt), meaning ‘Escort Vehicle, Strengthened’. This indicates that the new 30 tonne Panzer was meant to cover the same role as the Panzer IV, which was also known as the Begleitwagen in its development. This would have meant that small units of 30 tonne Panzers would have been used to accompany lighter tanks during operations, being responsible for taking out enemy strongpoints which could be destroyed using their high explosive shells.

In March 1937, this designation was changed into Infanteriwagen, or ‘Infantry vehicle’. This also indicates a change in the role it was meant to carry out, presumably to having to work alongside friendly infantry to overcome enemy defenses, probably closer to the British and French concepts of an Infantry tank. This would not last long and, in April 1937, the vehicle would receive its most known designation, Durchbruchswagen, or ‘Breakthrough vehicle’. Again, this probably came with a role change, a role that would stick with the German heavy tanks up to the E100. This breakthrough role, which also appears in both Soviet and French armored doctrines before the war, proposed the use of heavy tank units to punch through the enemy defensive line, thus creating a breach which could then be exploited by other armored and motorized divisions.

Construction

The construction of the first Durchbruchswagen began with a January 1937 order from Wa Pruef 6 to the Henschel company for the design of a chassis for the 30 tonne Panzer. This would cement a practice that would hold on for most of the German heavy tank development of having two companies designing the vehicle, Krupp doing the turret and gun and another company doing the chassis. Two versions were built, the D.W.1 and the D.W.2, meant to be delivered in the second half of 1938, mostly with automotive differences.

Drawing of the Durchbruchswagen 1 by H.L.Doyle showing the vehicle with a test weight instead of a turret. Source: Tiger and its Variants

Durchbruchswagen I

The Durchbruchswagen I was protected by flat 5 cm thick armor on the front, sides and rear, which was meant to be proof against the armor-piercing shells of the German 3.7 cm PaK, although it is unclear at which range this was supposed to be at. The Armor Piercing (A.P.) shell of the 3.7 cm could penetrate more than 5 cm of armor at point blank range. To give a comparison, the Panzer IV Ausf.F, which had the same gun, same engine, a very similar turret and the same 5 cm frontal armor, weighed just over 7 tonnes less than the Durchbruchswagen’s intended weight. A significant part of this difference can be accounted for by the thinner side, rear, top and bottom armor, although other differences between the two tanks make this comparison just indicative.

The roof and bottom of the hull were 2 cm thick. The armor at the front was stepped. However, both of the constructed vehicles were made out of ‘soft’ (not armor) steel, as they were meant mostly for automotive tests. Also, due to the inability of existing milling machines to fabricate such long 5 cm armored plates, the side armor was made from two parts, with a split at the front of the engine compartment. At the joining, they were riveted to an internal frame. This increased the weight of the vehicle and affected the structural integrity of the side armor.

For that time, this was quite thick armor. Only the Char B1 bis had thicker armor (60 mm front and 55 mm sides), with the SOMUA S35 also having similar armor (47 mm front, 40 mm sides). Furthermore, just like on the Tiger I prototype, there was a foldable armor plate that could be lowered using hand cranks to protect the drive sprockets at the front. This foldable armor plate was allegedly put through a protection test which it failed. There were two escape hatches in the bottom of the tank, one on the right front, close to the radio operator, and one at the rear left of the hull, in the engine compartment. This could be accessed through a door in the firewall that separated the engine from the crew compartment. While not specifically mentioned in any source, the Durchbruchswagen I hull probably had a driver’s visor in the front of the upper glacis and a hatch in the roof. The radio operator on the right side of the front hull also probably had a hatch in the roof and a ball-mount machine gun.

The engine was a 12-liter water-cooled gasoline Maybach HL 120 TR giving out 280 hp, placed at the rear of the tank. The TRM version of this engine also propelled the Panzer III, Panzer IV and their derivatives. The engine was coupled to a Maybach-Motorenwerk Variorex semi-automatic transmission, also used on the Panzer III, placed at the front of the tank. These could allegedly propel the vehicle to a maximum speed of 35 km/h. The steering system consisted of three Cletrac stages in series. A Cletrac system allows the transfer of power from one track to the other when steering, without the usual loss of power due to braking. The three stages allowed the use of three different turning radiuses, so the tank could make a shallower or tighter turn without losing power. However, problems appeared with the steering system, with the cast iron housing being broken twice. The exhaust was at the rear of the tank, coming down from the upper part of the rear of the vehicle. There were also problems with the brakes, as the first version, done by Henschel, gave out a lot of smoke when breaking, so the coating had to be replaced.

One of the only two known images of the D.W. tanks, showing the final drives, first roadwheel and first shock absorber of the D.W.2. Source: Tiger and its Variants

The running gear consisted of a drive sprocket at the front, an idler at the rear, three return rollers and five medium-size double road wheels on each side. They had rubber rims in order to decrease the noise made by the tracks. Due to the use of a torsion bar suspension, the road wheels were not symmetrically placed. The ones on the right side of the tank were slightly forward compared to the ones on the left. The torsion bars were square and hollow on the inside. They were very soft-springed, meaning that they could give a smoother ride in certain conditions, but could not handle rough terrain and would lead to a lot of pitching during driving and when stopping or starting. Two shock absorbers were mounted on each side, one on the first roadwheel and one on the last roadwheel. These were meant to assist these torsion bars, as they were subjected to stronger shocks, especially when stopping or accelerating. Also, bump stops were added to the suspension in order to stop the road wheels from being deviated too much and thus protecting the tank from bellying out. The tracks had a pitch of 300 mm. The pitch of a track is the distance between the centers of two subsequent track links. In general, decreasing the pitch could lead to better speed and ride, but also means more track links were needed, with more connections and more parts. The tracks were lubricated and could be fitted with rubber pads. The rubber pads would have made the tank quieter and less prone to damaging or destroying the pavement on roads, while the lubrication decreased friction and thus increased the speed of the vehicle. These were both characteristics that seem to have been carried over from half-track designs.

The crew probably consisted of five people as on other German tanks being developed at that time. This would have included the driver and radio operator in the front part of the hull of the tank, and a gunner, a loader and a commander in the turret. This would have been a very important feature of this vehicle, as it would have allowed the commander to focus on his duties of observation and tactical leadership instead of having to aim and load the gun.

The dimensions of the Durchbruchswagen are not available in any of the sources, but it can be reasonably assumed that they would have been similar to those of the VK30.01(H). This later vehicle had a length of 5.7 and a height of 2.6 meters. The width of the VK30.01(H), of 3.1 meters, was probably larger than that of the D.W. due to the different suspension system. Nonetheless, these values are also very close to those of the Panzer IV.

Drawing of the Durchbruchswagen 2 by H.L.Doyle, showing a Panzer IV-like turret. The main outside differences compared to the D.W.1 drawing are the one-piece side armor, the crew escape hatch in the lower side and the different side viewport for the driver. It is unclear if these differences are historical or just speculative. Source: Tiger and its Variants

Durchbruchswagen 2

Work on the Durchbruchswagen 2 was started halfway through 1937 and it mostly had automotive improvements. In the book ‘Tiger and its variants’, Doyle’s drawing of the D.W.2 shows it with the one-piece side armor. However, in the book ‘Germany’s Tiger tanks’, Jentz specifically mentions that the one-piece side armor was introduced with the VK30.01(H) neue Konstruktion, and thus the D.W.2 should have the two piece side armor. Similarly, ‘Tiger and its variants’ shows the addition of a hull side-escape hatch to the D.W.2 while ‘Germany’s Tiger tanks’ makes no mention of such a thing.

Automotive-wise, the larger stages of the previous Cletrac system were replaced with a three-stage differential with magnetic clutches. Not only did these allow for power to be transferred from one track to the other while turning, but a triple stage differential also allowed to reverse one track with respect to the other, thus allowing the tank to neutral steer. The Cletrac stage with the smallest turning radius was kept though.

Also, the track pitch was decreased to 260 mm, which is claimed to have significantly improved the ride of the vehicle. The torsion bars were also changed to a more rigid type, with a three-times larger springing constant.

Due to these changes, the drive sprocket, final drives and parking brakes also needed to be modified.

The shorter pitch tracks of the Durchbruchswagen 2. This is one of only two known photos of the D.W. tanks. Source: Tiger and its Variants

The Turret

These two hulls were supposedly trialed to test all the components and identify what improvements could be made for future projects. However, almost no details remain about these tests. What is certain is that the Durchbruchswagen was not accepted as built.

Work on the Durchbruchswagen turret was done in parallel to that on the hulls. Krupp sent the requested conceptual drawings for the turret in February 1937, and was quickly informed by Wa Pruef 6 to use it as a basis for subsequent development. In the March 1937 answer, Wa Pruef details the desired characteristics of the D.W. turret.

The turret was to have a turret ring diameter of 1,500 mm, smaller than that of the Panzer IV. Also, the turret would be rotated manually, as

“No plans are made for an electric drive for traversing the turret. Auxiliary traversing gear for the loader is to be included.”

The armor of the turret would be 50 mm all around, with a 20 mm external mantlet and a 15 mm turret roof, affording similar protection as the hull. There is no other information on the shape of the turret of the Durchbruchswagen, although H.L.Doyle’s line-drawing in ‘Tiger and its variants’ shows a Panzer IV-like turret with a large commander cupola at the rear, a crew access hatch and a vision port on each side.

The gun to be used in this turret was the same 7.5 cm Kampfwagenkanone L/24 that would be mounted on the early versions of the Panzer IV. In a meeting in January 1939 on the topic of the heavy 30 tonne Panzers, it was expressly specified that no gun larger than the short 7.5 cm should be pursued because the increased weight would have to be compensated by a decrease in armor, which was deemed unacceptable.

The main shell for this gun was the Sprenggranate 34 high-explosive shell. This shell weighed around 4.5 kg and had an explosive filler of almost half a kilogram. This was meant to be used against enemy infantry, machine-gun posts, anti-tank guns, bunkers and soft-skinned vehicles. For anti-tank purposes, a series of High Explosive Anti Tank (H.E.A.T) shells were introduced during the lifetime of this gun, with penetrations ranging from around 45 mm to over 100 mm, although they were introduced into service later. Two types of Armor Piercing Capped Ballistic Capped (A.P.C.B.C.) shells were also available, with a penetration of 54 mm to 60 mm at 100 m distance. An APCBC shell works basically as a normal Armor Piercing (A.P.) shell, but has two additional caps added to the tip of the shell. The first cap is made of soft metal and is meant to absorb a part of the shock on impacting the armor and thus preventing the armor piercing tip from shattering. The ballistic cap was a hollow light cone added on the top of the shell with the sole purpose of improving the aerodynamics of the shell. This improved both accuracy and the penetrating power, as the shell kept more of its kinetic energy at longer ranges.

Another machine gun (most probably an MG 34) would have probably been mounted coaxially with the gun. The instruction letter from March 1937 specifies that the radio should be mounted in the turret, behind the gun. However, this seems impossible to do in a Panzer IV-like turret. If the turret was as the one drawn by Doyle, then the radio would have almost certainly been mounted in the hull.

Krupp finished the D.W. turret in May 1939, building it from soft steel. It was then shipped to Magdeburg, where it was put on display along with other developments, such as the Panzer IV turret. Nothing is known about what happened after this with the turret.

The End of the Line

The Durchbruchswagen project melts into the subsequent VK 30.01 (H), which inherited many of the characteristics of the D.W. designs. The Durchbruchswagen design also underwent its last designation evolution in November 1939, also receiving the designation Vollketten 30.01 (H) alte Konstruktion.

Nonetheless, a final D.W. hull was constructed from armor plate for ballistic tests. This hull had some changes compared to the previous two hulls, having slightly different armor values that were closer to those on the VK30.01(H). This was completed after September 1940 and shipped to Kummersdorf for firing tests. No information about the results are currently available.

The armor scheme of the single D.W. hull constructed from armor plate. However, these thicknesses were changed to be closer to those intended for the VK30.01(H). Source: Germany’s Tiger Tanks, D.W. to Tiger I

A Note on Sources

There is almost no photographic evidence for the Durchbruchswagen. The only known photographs of the project were published in ‘Tiger and its variants’ and consist of a photograph of the tracks and one of the final drives at the front of the vehicle, along with a roadwheel and a shock absorber. This paucity of photographic evidence is disturbing. Other visual references include a 1940 armor scheme of the ballistic test hull and a 1945 British reconstruction of the D.W. hull based on the interrogation of Dr. Aders, the head of the design department of Henschel. Finally, two beautiful line drawings from Hillary Louis Doyle are available in the book ‘Tiger and its variants’, but how many of the details on it are based on historical references and how many are conjectural is unknown.

It is also important to note that there is annoyingly little information available on the Durchbruchswagen, with only three books treating it in any detail. Even so, most of the technical details and specifications come from the 1945 interrogation of Dr. Aders by the British and not from contemporary German documents, so they should be treated with a degree of skepticism.

Dipl. Ing. Erwin Aders, one of the main designers involved in the Durchbruchswagen project. Source: Tiger and its Variants

Conclusion

Nowadays, the Durchbruchswagen are mostly forgotten except for some mentions in a couple of books and their appearance in a popular video game. However, they played an important role in the development of German heavy tanks that would culminate in the Tiger tanks. They were the main designs worked on at a time when the German heavy tank doctrine was being crystallized. Also, they were very important in testing the capabilities of the German armaments industry and helping identify where research and development were needed, such as designing better armor milling, better suspension and better engines.

Nevertheless, the Germans would not adopt a heavy tank for the Wehrmacht until 1942, meaning that the German tank divisions went into the Second World War without such a vehicle. During the peak of the German offensive successes, when such a tank would have been most useful in breaking down Polish, French, or Soviet defensive lines, none was available. The Germans nonetheless achieved great success despite the thin armor of their tanks due to excellent communications, training, leadership, and tactics.



Illustration of the Durchbruchswagen 2 based on H.L.Doyle’s drawing produced by Tank Encyclopedia’s own David Bocquelet. The hull side is in one piece

Specifications

Dimensions Around 5.7 x 3.1 x 2.7 m
Armament 7.5 cm Kampfwagenkanone L/24
Machine Guns 2 x MG 34
Armor 50 mm hull front, rear and sides
20 mm hull roof and floor
50 mm turret front, rear and sides
15 mm turret roof
Weight Around 30 tonnes
Crew Probably 5 (driver, co-driver, commander, gunner, loader)
Propulsion Maybach HL 120 TR, 280 hp
Max Speed Allegedly 35 km/h
Total Operated 3 hulls and 1 turret built

Sources

Panzer Tracts No.6 Schwere Panzerkampfwagen D.W. to E100 including the Tigers, T.Jentz and H.L.Doyle
Germany’s Tiger Tanks, D.W. to Tiger I, Design, Production and Modifications, T.Jentz and H.L.Doyle
The Tiger tank and its Variants, W.Spielberger and H.L.Doyle


Categories
WW2 German prototypes

Schwerer-Flammpanzer auf Tiger I (Flammanlage auf Tiger I – ‘Flammpanzer VI’’)

Nazi Germany (1944-45)
Flamethrower Tank – Experimental Only

There is something about a flamethrower that induces the primordial fear amongst those on the receiving end. The awe of seeing a sheet of flame projected towards you with little or no chance of stopping it was recognized as a very effective psychological weapon during World War I, when these devices first started to be fielded. Even as far back as then, there were ideas and plans to mount these flamethrowers into tanks. An armored all-terrain platform makes a lot of sense for a flamethrower-carrier, as it is protected by its armor from the small arms of the enemy but also able to traverse the rough or broken ground in front of the position. Further, whilst a man-portable system was limited by the ability and stamina of the man hauling it, a vehicle was not. A vehicle-mounted flamethrower system could carry far more fuel for a bigger flame thrower with a longer range than was possible with a man-portable system.

The Germans, right from World War I, were fans of flamethrowers and understood the potential of them both in their direct military application for clearing an enemy position as well as for their psychological effect. Various German tanks in World War II were trialed with flamethrowers, although some are better known than others. One of these projects that is mostly forgotten and was never realized in a vehicle was the fitting of a heavy flamethrower into the hull of a Tiger I, the Schwerer-Flammpanzer auf Tiger I.

Flamethrowers mounted on the Panzer I (Pz.Kpfw.I Ausf. A), also known as ‘Flammpanzer I’, were used in North Africa against the British and a version known as the ‘Flamingo’, based on the Panzer II (Pz.Kpfw.II(F) Sd.Kfz.122), also known as ’Flammpanzer II’, was used on the Russian Front. Both of these vehicles saw relatively limited service. They were simply too vulnerable to enemy fire with thin armor which even an anti-tank rifle could penetrate from the front. As such, the poor range of the flame projectors they mounted left them very vulnerable to being penetrated as they had to get too close. This, and carrying hundreds of liters of fuel inside the tank was thus a recipe for disaster for the crews. The Flammpanzer I had mounted its projector in the turret alongside a single machine gun but the Flammpanzer II went for two nozzles, one on each front mudguard over the tracks (Spritzkopfe – Spray Heads). Each was independently operable, able to be rotated through 180 degrees. The turret was changed to include new vision ports permitting a better view of each nozzle as it worked and just a single machine gun. Flame time for the Flammpanzer II was limited. Just 160 litres of fuel were carried, enough for up to 80 ‘shots’ lasting up to 2-3 seconds each with the usual method being to douse the target with fuel before igniting it.

Flammpanzers I and II (Flamingo) showing the turret-mounted flame-projector on the Panzer I and the front-wing mounted projectors on the Panzer II. Source: Jentz et al. (left)

A solution to the lack of armor on the Flammpanzer I and II was to use the hull of a more heavily armored tank. Whilst it was on a much slower platform, a successful flamethrower was retrofitted to captured French Renault Char B tanks (Pz.Kpfw.B2 (F1)). Powered by a J-10 Motor driving a pump rather than being reliant upon cylinders of compressed nitrogen gas as the propellant like on the Flammpanzer II, this system had a range of 40 to 45 metres with enough fuel for about 200 separate bursts. This was a new type of fitting designed by Wegmann, although the actual flamethrower was designed by Koebe. This partnership paired the heavily protected Char B hull with the flamethrower, allowing, at least in theory, for the vehicle to get close enough to the enemy to make use of it.

Two views of the front-mounted flame-projector fitted to the front of the captured French Char B2 (Pz.Kpfw.B2 (F)). Source: Jentz et al. via The Tank Museum, England

The Panzer III (Pz.Kpfw.III (F) Sd.Kfz.141/3) flamethrower version, also known as the Flammpanzer III, was different to the Pz.Kpfw.B2 (F) using a Koebe* HL II 40/40 1000/20 pump which, in turn, was driven by a two-stroke 28 hp Auto Union ZW 1101 (DKW) (1,100 cc) engine. It could achieve a jet of burning flame oil out to just 60 metres at a pressure of 1.52 to 1.72 MPa (15 to 17 atmospheres) and a rate of 7.8 litres per second. The fuel mix itself was a mixture of oil and petrol to create a thickened burning fluid which was easily ignited by means of Smits glow plugs (Smitskerzen). This system had far better mobility than the Pz.Kpfw.B2 (F) retrofitted system, but still required improvement and found limited use.

*(Koebe was the firm of Hermann Koebe Feuerwehr-Geraete-Fabrik of Berlin, a manufacturer of fire-fighting equipment)

Panzer III (Pz.Kpfw.III (F) Sd.Kfz.141/3) ‘Flammpanzer III’ in action. Source: Jentz and Doyle
Koebe HL II 40/40 1000/200 auxilliary pump and fuel tank (on top) as used in the Pz.Kpfw.III (F) to deliver the flame-fuel. source: Jentz et al.

Enter the Tiger

Despite the successful use of various flamethrower-armed vehicles, including tanks and half tracks, during the war, it was clear to the Germans that the short range of the flame systems used meant that the vehicles carrying them had to get too close to the enemy and this rendered them vulnerable to fire. The solution was twofold: first, put the flamethrower on a heavily armored platform (like had been tried on the Pz.Kpfw.B2 (F)), and secondly, partner this with a new, longer-range flamethrower system.

At the end of 1944, a solution was proffered by Hitler. On 5th December 1944, during a conference, he requested that a long-range flamethrower should be mounted behind as heavy an armored chassis as possible. Various heavy tank projects had been suggested up to and including the Maus (which had been through its own flamethrower development by this time). The Tiger II chassis was the most well armored vehicle in service which was in production at the time, but chassis for that vehicle were at a premium. The next best thing of course was the Tiger I (Sd.Kfz.181 – Tiger Ausf. E), a vehicle which had finished production and for which there were hulls available as vehicles were brought back from the front for repair.

Repurposing these hulls for this use was not dissimilar from the idea to reuse hulls for the Sturmtiger programme, as it meant that a tank which might have had severe and irreparable turret damage could be reused for the war effort. Unlike the Sturmtiger though, this flamethrower idea would not require extensive rebuilding with a new superstructure and weapon system. Instead, the plan was much simpler. Hitler’s goal was a Flammpanzer with frontal armor which was impenetrable to enemy fire with a target of 250 mm, but the Tiger I, with armor up to 120 mm thick on the front, would have to do in the short-term. This demand was repeated by Hitler on 29th December 1944 and the task passed over to Obert Crohn of the Entwicklungskommission Panzer (Tank Development Committee).

Preserved Tiger 131 at The Tank Museum Bovington. Currently the only running Tiger tank in the world. Source: Mark Nash

Development

Reusing Tiger I hulls would mean there would be no need to design a chassis on which to mount this flamethrower but there were still technical hurdles to overcome. First was the flame-part of the problem and, on 23rd January, Obert Crohn reported a solution. It was a reversion to the older high-pressure gas-based delivery system but it would provide a significantly longer range flamethrower, at 120-140 metres. The mounting for the weapon was selected as being the machine gun port on the front of the Tiger, meaning it could be directed by the man in the front right who had previously had the role of radio operator/hull machine gunner, but there was still the issue of the fuel tanks. The interior of the Tiger was crammed full already with the equipment it needed to function as a tank as well as the turret basket, ammunition etc., so there were only two easy options for the fuel. Either it would have to be hauled in a trailer behind (a solution adopted famously by the Churchill Crocodile) or else the turret would have to be removed to create the space. The advantage of a trailer idea is that the main gun could be retained, but this would come at a cost. The trailer would be vulnerable and, since the surplus Tiger Is were those with damaged turrets anyway, the turretless internal-fuel-stowage option was chosen instead. This would be lighter and avoid the vulnerable trailer but had its own flaws. First was the lack of armament as the hull weapon had been replaced, and the turret weapons had been lost. This would receive separate consideration for a solution. The second problem was the profile. A turretless Tiger would draw significant attention and be an obvious target on which an enemy could focus fire.

Certainly, production would not have been a significant issue as the modifications were modest but the whole concept had to be called into question. Major General Thomale was a fan of the flamethrower but only in limited circumstances. Specifically, he liked them on small, light, and maneuverable vehicles which could target the odd stubborn strongpoint and the Tiger I was neither small, light, nor particularly fast even with a turret removed. His second point was also valid. With its main gun, the tank could pick off the enemy at combat ranges up to 2,500 metres meaning a significant safety distance from their fire and, with 80 rounds, could do so many times. A flamethrower meant getting very, very close and offered relatively few attempts to destroy the enemy. Despite the limited advantages of the system, he was therefore against it.

The flame thrower system designed could still be used, but would have to be mounted on something smaller and lighter instead, and the Jagdpanzer 38 was selected as the replacement. Nonetheless, the idea of a flamethrower on the Tiger I was not over.

On 19th March 1945, despite the extremely dire war situation, the project, named ‘Flammenlage auf Tiger I’ (Flame mounting on Tiger I) or ‘Schwerer-Flammpanzer auf Tiger I’ (Heavy flamethrower on Tiger I) was still being listed as a project under development and Hitler ordered Maj.Gen. Thomale to fit the flamethrower system to a turretless Tiger I with the second idea of increasing the thickness of the armor on the front. Quite how much additional armor was meant to be added is not clear nor how it was to be done, but perhaps something akin to the method used on the Ferdinand/Elephant is the best approximation as to which would have been adopted. The Sturmtiger was similarly up-armored with an extra 50 mm plate, which suggests the frontal armour of the Schwerer-Flammpanzer auf Tiger I could have been increased to around 150 mm across the front, a lot less than Hitler might have wanted but certainly a significant improvement.

The original Tiger (P) armor was significantly improved with heavy armor plating bolted to the original front to improve protection. Source: Jentz and McKaughan
Prototype Sturmtiger with 50 mm thick additional front armor plate bolted on the lower front section.

Further progress was still reported into the final days of Nazi Germany, with an update from Wa Pruef 6 on the project as late as 3rd April 1945. In this report, Obert Holzhauer (head of Wa Pruef 6) reported that, following Hitler’s orders, the first steps in putting together this experimental heavy flamethrower on a Tiger I had taken place at Wegmann, Kassel on 21st and 22nd March with completion of the project estimated by 15th April. The Tiger I to be used had been dispatched by train from Kummersdorf on 17th March but, due to enemy bombing, had been delayed until 3rd April 1945. From Kassel, the vehicle was then sent to the firm of MIAG at Braunschweig for assembly there under supervision of men from Wegmann.

This additional movement and Allied bombing meant that the target completion date of 15th April was missed and the vehicle was never completed. Likely, work on actually fitting the system was never even started before Allied forces overran the facility. This is confirmed by a British intelligence report of the time which stated:

…It is believed that this equipment never progressed beyond the experimental stage and no specimen has yet been recovered….

– War Office. (26th July 1945). Technical Intelligence Summary Report 182 Appendix F ‘Flame thrower mounted on Pz.Kpfw. TIGER MODEL E (Sd.Kfz.181)’

System

The new flame-system that was to be fitted to the Flammenlage auf Tiger I reverted back to using compressed nitrogen and special reduction valves (obtained from the Kriegsmarine) which raised the pressure output from the tanks. This meant that this new system had abandoned the motor-driven-pump system. In this way, the pressure of the system could be raised from 1.52 to 1.72 MPa (15 to 17 atmospheres) to 2.03 to 2.53 MPa (20 to 25 atmospheres). With this increased pressure, the system could deliver a jet of burning fuel out to a range of 120 to 140 metres. A pair of 400-litre fuel tanks* would be fitted on the inside (there was more room because no turret was required), providing enough fuel for 16 to 20 bursts, meaning each burst would use about 40 to 50 litres of fuel. At 2-3 seconds per burst, this means the system delivered about 20 litres per second.

The fuel was different to what had been used before. Koebe, when asked at the end of 1942 to design a long-range flamethrower for use on the Porsche-Maus, proved unable to develop a system with a range of more than 100 m. Even then it would have required a flame-nozzle (Spritzkopf) 22 mm wide and would have used 33 litres of fuel per second propelled by a 30 hp engine driving a pumping system. To project a flame even further would require a narrower (12-14 mm) nozzle, but the jet would disperse with range. To go further, therefore, the fuel needed to be thicker and it was this factor which meant a pump could not be used. Even with a range of 140 metres, this was still not ideal and Hiter, in March 1945, still wanted a thicker fuel to match the type used by the British on their flamethrowers, but there would be no time to develop an even thicker fuel. The projector itself, when fitted into the front of the Tiger, would have had only limited traverse. A range of motion of just 10 degrees in all directions was possible.

*(A British report from July 1945 on the project reported a single 300 litre tank, suggesting just a single fuel tank was found with the remains of the system when it was recovered and mis-estimated in volume)

Given that this project was relatively crude, it is hard to know exactly how many men would have been required to crew it, but some things are known. For example, the tank would have had to have kept its driver, located in the front left. Without any kind of remote-control over the direction of the flame-projector, the flame-projector located in the front right would need manual operation too and this would have meant the retention of the man who would usually operate both the hull machine gun and the radio. He would have been the flame-operator and likely still the radio operator too, although it was also identified that flamethrower tanks should have a second radio set in order to coordinate with supporting vehicles. This would suggest the use of a Panzerbefehlswagen Tiger hull which was fitted with both a Fu 5 and Fu 8 (Sd.Kfz. 267) or Fu 7 (Sd.Kfz. 268) radio sets, although on the Panzerbefehlswagen Tiger the additional set was fitted into the turret and would have to be relocated within the hull. No loader was required nor was a gunner, but a commander would certainly have had to be retained in order to coordinate the operation of the vehicle, which would therefore indicate a crew of 3 men. Even with the removal of the turret and ammunition, the two 400-litre tanks required would have taken up a lot of the internal space and it is doubtful there would be room for a fourth man and, in any case, there was no clear role for him anyway.

Automotive

As the vehicle was based upon an existing Tiger I hull, there were likely no changes made to whichever hull was to be used. As the Tiger I had gone through production, various minor changes were made to some internal and external fittings. Some were fitted with special air filters at the back, and others not. Early production Tiger I vehicles received the 650 hp Maybach HL 210 650 hp petrol engine whilst later vehicles received the 700 hp Maybach HL 230 petrol engine. Early production Tigers used rubber-tyred road wheels but these were later replaced with a more resilient steel-tyred type. Without knowing which hull was to be used, it is impossible to know exactly what the Schwerer-Flammpanzer auf Tiger I would have looked like, but the essentials of the automotive system would be identical.

Layout

Changes to the Tiger I hull were relatively modest. Removal of the turret meant leaving a large hole in the roof of the tank which was obviously a serious hazard in combat so this would have been covered with a large armor-plate. Already discussed is the additional armor on the front, although how this might have looked around the machine gun mounting is unclear. Other than these changes and the interior changes, like the removal of the ammunition racks etc., there would have been few changes inside and most of the work would have been done on the roof. For the prototype, it is possible that just a single plain disc of metal welded or bolted over the hole where the turret would have sat would have been employed. This would have retained the front crew hatches but meant that a commander in the back would have been unable to get out except by these front hatches. Given the hundreds of litres of fuel he would be sat next to, this seems highly improbable for any design which would ever have been authorised for production and the description in the British 1945 report provides an additional clue.

Other Armament

Whilst with no turret and hull machine gun the vehicle might seem otherwise unarmed, it was to get a new machine gun, most likely either an M.G.34 (Maschinengewehr 34) or M.G. 42. This would not have been mounted within the vehicle, but this time mounted externally. This would have been controlled from inside, again supporting the proposition of a third crew member, and would have been mounted on the outside of the cover plate over the turret-hole.

The mounting of such a weapon was certainly not a new idea and was mounted on various Sturmgeschütz in the form of a 7.92 mm M.G. 34, fitted with a 50-round drum mounted behind a short and sharply curved gun shield. Under the gun was a small optical sight which permitted the man below the armor to see where he was firing. Reloading however, had to take place externally.

Roof-mounted remote-controlled weapon station as featured on a Jg.Pz.38t (left) and from an Allied Intelligence Bulletin (right). Source: pzfahrer.net/hetzermgs.html and Intelligence Bulletin May 1945

In order to provide any value to the commander, he would have needed to be provided with some optics as the small optic on even the roof-mounted machine gun would be wholly inadequate for the purposes of command. A hatch would also have been required for observations, access or egress to the vehicle, changing barrels, or reloading/clearing stoppage on the machine gun. Despite the description of the “single continuous roof plate”, it would appear that any development of this vehicle would have needed to include at least a moveable optic and hatch for him, or even just a repurposed tank cupola.

One extra piece to consider is that the Tiger was fitted with a self-protection system launching S-mines to protect against enemy infantry. As this Schwerer-Flammpanzer auf Tiger I was, by definition, having to get very close to the enemy in order to use its primary weapon, it would be logical to assume that this type of system would have been adopted for any production of the Schwerer-Flammpanzer auf Tiger I even if the prototype being assembled did not have them. Further, a lot of flame throwing vehicles used by the Germans carried smoke-candle launchers in order to create a smoke screen to protect them from enemy observation. Here again, the addition of smoke grenade launchers on the Schwerer-Flammenpanzer auf Tiger I is a very reasonable assumption as once it had ‘flamed’ its target it would need to withdraw and a smoke screen provides ideal screening during such a manoeuvre.

Conclusion

The overall idea was not a bad one. A flamethrower certainly had some practical military value and served as a potentially very effective psychological weapon against the enemy too. This fact was reinforced in February 1944 by considerations from Panzer Grenadier Division ‘Grossdeutschland’, which recommended the use of a motor-driven ‘howling siren’ to accompany the use of the flamethrower to maximise the demoralisation effect.

Early flame-throwing attempts had been too small (Panzer I), too lightly armored (Panzer II) and too short in range (Panzer III et al.). A heavy flamethrower paired with a heavily armored hull from the Tiger I seems like a system which could have fulfilled the requirements but it was simply flawed in premise.

With very little development time on hand and with the progress of the war going so badly, this was a weapon system which was not going to enter production. The days of assaults against fixed enemy positions like bunkers and trenches, for which a flamethrower is best suited, were over by 1945, as most of the fighting was defensive in nature. The Schwerer-Flammpanzer auf Tiger I was never finished so no photos of it exist and whatever plans may have existed for it are believed to have been lost. Outside of reports, both German and British, the project remains unknown, and the reader is therefore reminded that the discussion over the vehicle is speculative, as is the artist’s rendering.



Illustration of the Schwerer-Flammpanzer auf Tiger I (Flammanlage auf Tiger I – ‘Flammpanzer VI’’) based on existing descriptions. Modified by Pavel Alexe, based on wok by David Bocquelet.

Sources

Doyle, H., Jentz, T., Sarson, P. (1995). Flammpanzer German Flamethrowers 1941-45, Osprey Publishing, UK
Doyle, H., Jentz, T. (2011). Panzerkampfwagen III Umbau. Panzer Tracts, Maryland, USA
Jentz, T., McKaughan, J. (1995). Elefant Panzerjager Tiger (P). Darlington Productions, Maryland, USA
Jentz, T., Doyle, H. (2008). Panzer Tracts No.6-3 Schwere Panzerkampfwagen Maus and E 100.
US War Department. (May 1945). Intelligence Bulletin Vol. III No.9. War Department, Washington, USA
War Office. (26th July 1945). Technical Intelligence Summary Report 182 Appendix F


Categories
WW2 German prototypes

VK30.01(D) and VK30.02(M) – Panther Prototypes

Nazi Germany (1942)
Medium Tank Prototypes – 4 Built

“…I was quite startled, however, by an unusual event in connection with the tank in question. In the spring of 1941, Hitler had given his express permission that a Russian officer’s commission be permitted to visit our tank training schools and armor production facilities, and had ordered that the Russians be allowed to see everything. During this visit, the Russians, when shown our Panzer IV, simply refused to believe that this vehicle was our heaviest tank. They repeatedly claimed that we were keeping our newest design from them, which Hitler had promised to demonstrate. The commission’s insistence was so great that our manufacturers and officials in the Waffenamt finally concluded that the Russians had heavier and better types than we did…”

– General Heinz Guderian, Erinnerung eines Soldaten/Panzer Leader

This should have been the first warning sign to the Germans that the Soviet Red Army was not as far behind technologically as they had believed. In 1941, World War II was in full swing, Germany had swept through most of Europe, and with the Channel blocking their advance into England, the only way left to go was east, turning on their one-time ally, the Soviet Union.

As early as July of 1940, Hitler had been thinking about invading the Soviet Union; he was counting on their obsolete and disorganized military to quickly fall to the blitzkrieg as the rest of Europe already had. Although Germany and the Soviet Union had signed a non-aggression pact in 1939, both countries still held a distrust of one another. This would be validated on the Soviet’s part when the Germans invaded on June 22nd, 1941.

At the start of Operation Barbarossa, the German invasion of the Soviet Union, Germany’s primary tanks were the Panzer III and the Panzer IV, both of which were mid-1930s designs. Even so, they were still seen as superior to anything the Russians could field. Indeed, the Panzer III’s 3.7 cm KwK 36 cannon would have no trouble at all punching through T-26s and BT tanks; but time had not stood still since the Germans were last allowed to examine the Soviet’s tanks. Whether through arrogance or ignorance, the Germans had failed to realize that Soviet tank development in 1941 had far outpaced their own. Only one day into Operation Barbarossa they would see this firsthand.

June 23rd, 1941, would see the combat debut of the T-34 and KV-1, the latter all but impregnable to German 3.7 cm and 5 cm anti-tank guns. The T-34 in particular was seen by the Germans as a massive leap forward in tank design, combining maneuverability, a powerful cannon, and good protection on account of its comprehensive use of sloped armor. The appearance of these new enemy tanks left the German army scrambling to find a solution to defeat them. The companies of Henschel and Porsche had been involved in work on a heavy breakthrough tank since early 1937 and late 1939 respectively, but this had not been seriously pursued up until this point. However, the appearance of the new Soviet tanks, and the promise of even better ones to come, led to much more focus being laid on the design that would eventually become the Tiger. Moreover, a new, more modern tank design was needed, incorporating the advantages of sloped armor but retaining the maneuverability that had made the Panzer III and IV so successful.

On July 18th, 1941, Rheinmetall-Borsig was contracted to develop a new tank cannon specifically to defeat the heavy Soviet armor encountered on the Eastern Front. It was to be capable of penetrating 140 mm (5.51 in) of armor at 1 kilometer (0.62 miles). They were also asked to develop a turret to house it. This gun and turret was to be mounted on the VK45.01(H2) [Tiger], but that project instead went with an 8.8 cm gun in a different turret, leaving the 7,5cm gun for what would become the Panther. For this purpose, the turret would be redesigned, becoming more squat and losing the side hatches and rear machine gun mount.

The 7.5 cm cannon was originally designed with a barrel length of L/60, or 60 calibers; this gave it a barrel length of 4,500 mm (177.2 inches). However, as the gun turned out to be slightly anemic, the barrel length was increased to L/70; resulting in a length of 5,250 mm (206.7 inches). This gun would be standardized as the 7.5 cm KwK 42 L/70.

The Rheinmetall-Borsig turret and 7,5cm cannon, here still 60 calibers in length, mounted on the VK45.01(H2) wooden mockup. To the left of the VK45.01(H2) appears to be another Tiger hull mockup, with another version of the turret that more closely resembles the turret that would be used on the Panther. Source
Rear view of the Rheinmetall-Borsig turret and 7,5cm cannon mounted on the VK45.01(H2) wooden mockup. Source

Upon experiencing the shock of encountering the T-34 firsthand at the Battle of Mtsensk on October 6th, 1941, General Heinz Guderian, the commander of the 2nd Panzer Army, sent for a commission to come and study the T-34 tanks that had been knocked out, and to talk to the men that had been involved in fighting them to determine what advantages the Soviet tanks possessed over the German vehicles, and what could be incorporated into new German designs.

The Special Armor Investigation Committee was led by Oberst Sebastian Fichtner, head of Waffen Prüfämter (Weapons Testing Office) 6, or Wa. Prüf. 6, the German organization in charge of tank development. The team included Heinrich Ernst Kniepkamp (senior engineer at Wa. Prüf. 6), Major Ruden (also of Wa. Prüf. 6), Otto Wunderlich (representing Daimler-Benz), Erwin Aders (representing Henschel), Director Dorn (representing Krupp), Engineer Oswald (representing Maschinenfabrik Augsburg-Nürnberg (M.A.N.)), Ferdinand Porsche (representing Porsche), Engineer Zimmer (representing Rheinmetall-Borsig), Oskar Hacker (representing Steyr), and Walter Rohland (representing Vereinigte Stahlwerke).

The commission arrived at the front on November 18th, 1941, and stayed until the 21st. During this time they heard the experiences of officers of the engineering corps, as well as suggestions from a tank repair company on how best to improve air filters to deal with the dusty conditions of the Russian summer. They examined a recent battlefield and met with repair and recovery personnel of the XXIV Panzer Korps.

While at the front, the commission examined several knocked out T-34s. They quickly determined three design advantages the T-34 possessed over the Panzer III. The first, which has been pointed out already, was the sloped armor, which afforded greater protection than flat armor of the same thickness. The second was the suspension; the T-34 had five large roadwheels and no return rollers, giving a smoother ride and greater suspension travel. In addition, its wide tracks gave low ground pressure, ensuring that it did not bog down on soft terrain. The third promising feature of the T-34 was the long gun barrel overhanging the front of the tank. This had previously been avoided by German tank designers as it could complicate maneuvering in forests and cities. A longer barrel affords more time for the shell to accelerate before leaving the cannon, resulting in better muzzle velocity and thus better armor penetration.

General Guderian laid out for them the issues experienced so far and requested the following:

  • Current tanks should be up-gunned.
  • New tanks must be made with wider tracks and lower ground pressure to deal with the Rasputitsa mud. Tanks must be able to drive cross-country and on unimproved trails in all seasons.
  • The new tank must have heavier armament, improved armor protection, and higher tactical mobility compared to previous designs. It should also have a more powerful motor and maintain a high power-to-weight ratio.

With their work done, the commission returned to Germany to distribute their findings.

Sebastian Fichtner was opposed to starting development on an entirely new tank, as the VK24.01, the fruit of the previous VK20 project to replace the Panzers III and IV, was nearly completed. However, the Reich Minister for Armaments and Ammunition, Fritz Todt, disregarded Fichtner’s concerns and gave the go-ahead to start work on a new tank.

Wa. Prüf. 6 therefore put forth a design competition on November 25th, 1941, issuing contracts to the firms of Daimler-Benz and M.A.N. to develop a new tank with the following parameters:

  • Combat weight of 30 to 35 metric tonnes
  • Maximum width of 3,150 mm (10’4’’)
  • Maximum height of 2,990 mm (9’9.7’’)
  • Minimum ground clearance of 500 mm (19.7 inches)
  • 60 mm (2.36 inch) thick frontal armor, sloped at 35° from the horizontal
  • 40 mm (1.57 inch) thick side armor, sloped at 50° from the horizontal
  • 16 mm (0.63 inch) thick floor and roof armor
  • Main armament was to be Rheinmetall’s 7,5cm cannon
  • Engine expected to be between 650 and 700 metric horsepower
  • Steering mechanism was expected to be the L 600 C unit
  • Speeds of between 4 kph (2.5 mph) in lowest gear and 55 kph (34.2 mph) in top gear
  • Cooling system capable of operating in temperatures up to 42° C (107.6° F)
  • Capable of running for 5 consecutive hours

The design was expected to be ready by Spring of 1942.

Remarkably, on the very same day the new design competition was ordered, M.A.N. had drafted a new version of their VK20.02 incorporating sloped armor (Drawing No. Tu 13947). This design strongly resembles M.A.N.’s later design for the VK30.02 [Panther], and even more so the little brother of this design, the Gefechtsaufklärer Leopard. Assuredly this is no coincidence, as both M.A.N. and Daimler-Benz used experience gained with the VK20 series of tanks in creating their VK30 designs. Source: Panzer Tracts 5-1

Development of the M.A.N. Design


Illustration of the M.A.N. design by Andrei Kirushkin

In response to a postwar inquiry as to what inspired the Panther design, M.A.N. stated that, “Previous steps were design studies conducted under the names VK20.01, VK24.01, and VK30.01. Based on requirements established by Wa. Prüf. 6, they were reworked to slope the walls like the Russian design [T-34].” No other mention of VK24.01 or of a VK30.01(M) have been found. If they existed at all, they have been lost to time.

M.A.N.’s design team, led by Paul Max Wiebicke, utilized the turret developed by Rheinmetall-Borsig for mounting the 7.5 cm cannon. The turret was placed in the center of the tank as far back as possible to reduce the length of the barrel overhanging the front of the tank. Secondary armament consisted of two 7.92 mm (0.31 inch) MG 34 machine guns. One was mounted coaxially to the right of the main cannon, and the other was given to the radio operator to fire through a bow position.

Crew layout was typical for German tanks, driver and radio operator/machine gunner in the hull, with the driver on the left and the machine gunner on the right; gunner, commander, and loader in the turret, with the gunner and commander on the left and loader on the right of the gun. Hatches were placed in the roof above the driver and radio operator; this provided an easier means to evacuate wounded crew members than the side hatches the Daimler-Benz design used. An escape hatch for the turret crew was placed on the rear of the turret.

Frontal hull armor was 60 mm (2.36 inches) thick, sloped back by 55° from the vertical (both upper and lower glacis). Side hull armor was 40 mm (1.57 inch) thick, vertical behind the tracks and sloped back by 40° above them. The rear of the hull was 40 mm (1.57 inch) thick with a 30° reverse slope. The hull roof and belly were both 16 mm (0.63 inch) thick at 0°; as was the turret roof, although the forward section was slightly angled, at 85° from the vertical. The front of the turret was 80 mm (3.15 inches) thick, sloped at 12°; the sides and rear were 45 mm (1.77 inch) sloped at 25°. The overall dimensions of the design were 6.839 meters (22’5.3’’) long excluding gun barrel, or 8.625 meters (28’3.6’’) including the barrel; 3.270 meters (10’8.7’’) wide, and 2.885 meters (9’5.6’’) tall including the turret, or 2.314 meters (7’7.1’’) tall excluding the turret.

The powerplant was originally suggested to be a 650 hp liquid-cooled two-stroke V8 diesel engine being developed at M.A.N.’s Augsburg plant. Despite the fact this engine had been in development since 1940, originally being designed for 450 hp output, Fichtner urged M.A.N. to push for 700 hp. Development of this engine was slow and it became too large and heavy, eventually being abandoned. Instead, M.A.N. went with Maybach’s HL 210 engine; bringing in Maybach to do the work of mounting the engine and designing the cooling system and other accessories. Air for the engine was sucked in from under two protective domes mounted in the middle of the engine deck, while two fans, one on either side of the engine block, circulated air through the radiators. Interestingly, the fans were driven by bevel gears and shafts, as opposed to fan belts. The Maybach engine would power a driveshaft passing through a 250×250 mm (9.8 inch) square shroud under the fighting compartment, and into a front-mounted transmission, as was common for German tanks. The transmission was an AK 7/200 unit of the standard mechanical type. It was coupled to an L 600 C hydraulic, controlled differential, regenerative steering mechanism that was also used on the VK45.01(H) [Tiger]. M.A.N. had originally wanted to use solid disk brakes for steering but was told that these would cause issues with heat from friction.

The VK30.02(M)’s suspension consisted of three rows of 860 mm (33.9 inch) diameter roadwheels, mounted on double torsion bar suspension. With tracks that had two rows of guide horns, one row of wheels ran on the outside of either row of guide horns, and the center row of wheels ran between them. The roadwheels of the center row were double units, resembling two normal roadwheels bolted together. The leading axle carried a central double wheel. The second axle carried a pair of single wheels flanking the first roadwheel on either side; this was repeated four times down the length of the suspension. This design was described as an ‘interleaved eight wheel setup’, as there were eight axles, even though each axle carried more than one wheel. Hemscheidt HT 90 shock absorbers were mounted to the second and sixth axles. Suspension bumpers had to be placed under the first, second, and seventh roadwheel arms to keep the roadwheels from traveling too far, overloading, and breaking the torsion bars. This limited suspension travel to a still impressive 510 mm (20.1 inches).

This complicated suspension system, combined with a wide track (660 mm (26 inch)) gave the tank a smooth ride and a consistent, low ground pressure of 0.68 kg/cm2 (9.67 psi). Although this type of suspension was already being used on half-tracks and on the Tiger tank, there was still trepidation from some regarding its use over more traditional designs. Equally, there were people who felt it was the way forward, such as Sebastian Fichtner and Heinrich Kniepkamp.

The VK30.02(M) carried 750 liters (198.1 gallons) of fuel, giving it an impressive projected on-road range of 270 km (167.7 miles) and an off-road range of 195 km (121.2 miles)*. Top speed was 55.8 kph (34.7 mph) and sustained road cruising speed was 40 kph (24.9 mph). The design was capable of a vertical step of 826 mm (32.5 inches) and a gradeability of 35°. Ground clearance was 500 mm (19.7 inches). The floor space of the fighting compartment was calculated as 7.26 square meters (78.1 square feet), but this did not include the steering mechanism, transmission, and other components, which if factored in would reduce the overall fighting space dramatically.

Shortly after work started on the VK30, M.A.N. was also tasked with creating a light scout version of the tank; this would become the VK16.02. The VK16.02 generally resembled a smaller version of the VK30.02(M), and very strongly resembled the VK20.02. In January 1942, Wa. Prüf. 6 transferred development responsibility for the VK16.02 to MIAG, to allow M.A.N. to focus on the VK30.02. In theory, Daimler-Benz also would have been developing a version of the VK16.02 based on their own tank, however no documentation regarding this survives.

On January 22nd, 1942, Paul Max Wiebicke and Otto Meyer (the General Manager of M.A.N.) met with Fichtner, Kniepkamp, Oberst Joachim von Wilcke, and a Major Crohn (the latter two also being members of Wa. Prüf. 6, although their roles are unclear) to discuss their VK30 design. The M.A.N. representatives reported that although they had settled on 32.5 metric tons as the weight of their design on December 9th, 1941, changes to the design had increased the projected weight to 36 metric tons. Wa. Prüf. 6 had apparently already been informed of the change, and constructed the scale model of the M.A.N. design so to reflect this. Wiebicke and Meyer were also shown the scale model of the Daimler-Benz design at this time, remarking that it was “very attractive”. The two tank models were to be shown to Hitler at a meeting at his headquarters the next day, on January 23rd. During the meeting on the 23rd, Fritz Todt decided that another meeting between the two companies should be held, so that the two designs could be standardized against each other. The date for this was set as February 2nd, 1942.

The scale model of the M.A.N. design. Source

While the steering mechanism for the VK30 was intended to be the L 600 C, M.A.N. had been developing simplified alternative designs, claiming that only by using their simplified steering mechanism could they build their tank with a pointed front hull. Wa. Prüf. 6 agreed to this, as long as the steering mechanism was ready before August 1942.

With most people of influence preferring the Daimler-Benz proposal, M.A.N. decided they needed to do something to make their design more appealing. What they came up with was sealing the engine compartment with a rubber lining to allow deep wading. With the engine compartment watertight, it would be able to operate underwater so long as the air intake on the top of the engine deck wasn’t submerged. The radiators, which were mounted vertically on either side of the engine, were not encompassed by this watertight compartment; instead they were exposed to the water whereby they could radiate heat. Because the cooling system was designed to flood whenever the tank entered water, all parts involved had to be impervious to water damage. All that had to be done to ready the tank for deep wading was shutting off the engine fans, which could be done from the driver’s position, and closing open ports, such as the air intake covers. Unfortunately, as would be discovered later, the rubber that kept the water out was also very good at keeping heat in. Heat buildup in the engine, from a wading system that was never even requested, would lead to many breakdowns and issues before it was fixed.

On February 2nd**, Paul Wiebicke, as well as Friedrich Reif (another worker from M.A.N.), went to the Heereswaffenamt building in Berlin to meet with Fichtner, Kniepkamp, von Wilcke, Crohn, and the design team from Daimler-Benz. When they arrived, they were informed that the meeting with Daimler-Benz had been cancelled, as Wilhelm Kissel (head of the Daimler-Benz board of directors) had managed to convince Reichsminister Todt to end the collaboration between M.A.N. and Daimler-Benz, and to allow Daimler to start work on building their prototypes. Regardless, the M.A.N. team had a constructive meeting regarding their tank design, and Sebastian Fichtner reassured them that Daimler was only being given permission to construct prototypes, not that they had been declared the winner of the competition. However, only a few days later, on the evening of February 10th, Fichtner again spoke to the M.A.N. representatives and informed them that after further discussion, Todt had approved the Daimler-Benz design for mass production.

**Germany’s Panther Tank gives this date as February 3rd, while it is in agreement with other sources that the meeting was supposed to take place on February 2nd. This could be a typo, but it is also possible the meeting had been postponed a day, before being cancelled.

The trip to Berlin had not been a total loss however, as M.A.N. was able to submit their final design to Wa. Prüf. 6, only one day after Daimler-Benz had done the same. Even though it was their ‘final’ design which they submitted as their entry, they were still making changes to it, some details of which were discussed at this meeting. The previous requirement that the M.A.N. design needed to be able to use the Daimler-Benz diesel engine was dropped, on account of the fact that cooperation between the companies was ended. Wiebicke and Meyer knew that Daimler wanted to deliver their first prototype by May of 1942, so they declared M.A.N. would also make this promise. Minor changes to the design suggested by Wa. Prüf. 6 had been incorporated or clarified by February 20th. The winner of the VK30 competition would be chosen following a presentation of the two designs in Berlin on March 3rd.

Development of the Daimler-Benz Design


Illustration of the Daimler-Benz Design by Andrei Kirushkin

Daimler-Benz’s VK30 design was a much closer copy of the T-34 than M.A.N.’s design. It retained the all-round sloping armor, forward mounted turret, and rear-mounted transmission – a feature uncommon in German tanks. The VK30.01(D) was armed with the Rheinmetall 7.5 cm cannon as per Wa. Prüf. 6’s design requirements, however Daimler opted to go with their own turret design instead of using the one developed by Rheinmetall. Secondary armament was identical to the M.A.N. design, two 7.92 mm (0.31 inch) MG 34 machine guns, one mounted coaxially to the right of the main gun, and another fired by the radio operator through a slot in the hull. Daimler-Benz’s turret had a turret ring diameter of 1600 mm (63 inches), 50 mm (2 inches) less than that of the Rheinmetall turret used on M.A.N.’s design; this would be its downfall.

Frontal hull armor was 60 mm (2.36 inches) thick, sloped back by 55° from the vertical (both upper and lower glacis). Side hull armor was 40 mm (1.57 inches) thick, vertical behind the tracks and sloped back by 40° above them. The rear of the hull was thicker than the sides, 50 mm (1.97 inches) sloped at 25°. The turret roof, hull roof, and belly were all 16 mm (0.63 inch) thick. The turret was sloped 30° all around, with frontal thickness of 80 mm (3.15 inches) and sides and rear of 45 mm (1.77 inches). The overall dimensions of the design were: 9.015 meters (29’6.9’’) long (including gun barrel), 3.280 meters (10’9.1’’) wide, and 2.690 meters (8’9.9’’) tall.

The VK30.01(D)’s suspension was similar to the suspension of the M.A.N. design in that it consisted of four sets of interleaved roadwheels, arranged in three rows. These roadwheels were 900 mm (35.4 inches) in diameter. The roadwheels of the center layer were built differently to the inner and outer layer wheels. Rather than being two single wheels joined together, as in the M.A.N. design, they had a groove down the middle, to accommodate the single row of guide horns on the tracks. Each set of roadwheels, meaning the leading central wheel, and the single wheels that flanked it on either side, was supported on its own U-shaped rocker bar. There were four such units on each side of the tank, each unit being connected to the hull by a suspension arm, the end of which opposite the rocker bar rested in a square bracket bolted to the side of the hull. Two of these brackets existed per side, with the forward one supporting the front two suspension units, and the rearward one supporting the rear two suspension units.

The suspension itself was leaf springs; three bundles per side. The first suspension unit was sprung on a small leaf spring bundle, bolted to the hull forward of the first square support bracket. The central two suspension units were each sprung on one side of a large central leaf spring bundle, mounted between the two support brackets. Finally, the rear suspension unit mirrored the first, and was sprung on another small leaf spring bundle, rearward of the second support bracket. The leaf spring suspension had the advantages of being easy to repair and maintain, and was already familiar to tank crews.

Relatively narrow tracks (540 mm (21.3 inches)) gave the 35 metric ton tank a ground pressure of 0.83 kg/cm2 (11.8 psi). The design was capable of a vertical step of 730 mm (28.7 inches) and a 40° grade, 5° better than the M.A.N. design. Ground clearance was 530 mm (20.9 inches).

VK30.01(D) suspension models, made by Tanks Encyclopedia’s own C. Ryan

Power would be provided by a Daimler-Benz MB 507 water-cooled V12 diesel engine, working through a rear-mounted KSG 8/200 hydraulic-assist transmission with an L 600 C hydraulic, controlled differential, regenerative steering mechanism. This transmission, developed jointly between Daimler-Benz and Ortlinghaus, incorporated a hydraulic multi-plate clutch, which afforded smooth gear changes and was easy to use. This choice of transmission was influenced by Daimler-Benz’s previous experience with the VK20.01(D). However, the hydraulic system had downsides as well; it was rather long compared to similar mechanical transmissions, and was not widely used. The only experience German heavy industry had with this type of transmission at the time was in small diesel switcher locomotives. To keep the tank compact, the engine was offset to the starboard side, with the output facing forward, from whence the powertrain was turned around and went through the transmission, which was mounted beside the engine.

VK30.01(D) engine-transmission layout blueprint. Source

The VK30.01(D) could carry 550 liters (145.3 gallons) of fuel, giving it a projected on-road range of 195 km (121.2 miles) and an off-road range of 140 km (87 miles)*. It also carried additional fuel tanks on the rear of the hull that could be jettisoned before going into battle. These auxiliary fuel tanks were likely intended to offset the fact that the M.A.N. design had a 200 liter (52.8 gallon) internal fuel capacity advantage over the Daimler-Benz design. Top speed was 56 kph (34.8 mph) and sustained road cruising speed was 40 kph (24.9 mph).

Cooling was provided by air sucked in through the tops of the protrusions on either side of the hull behind the turret. The air was passed over laterally-mounted radiators on either side of the engine and exhausted out the back. Four fans circulated air to the engine, one powered directly by the engine and the other three via V-belts. For deep wading, all hatches were sealed and air inlets and outlets would be closed off from the outside by valves. This would leave the engine running uncooled, giving a running time of a mere ten minutes before damage started to occur.

Crew was to consist of five men, as usual for German tanks; driver, radio operator/machine gunner, gunner, loader, and commander. Two convenient side hatches were provided in both the hull and turret to allow the crew to escape should the tank be knocked out. Because the turret was mounted so far forward, it was considered moving the driver into the turret with the rest of the crew, but after the initial design study this idea was not pursued. The area of the fighting compartment, from the engine firewall forward, was calculated as 6.43 square meters (69.2 square feet).

The scale model of the Daimler-Benz design. Source: Peter Chamberlain

On the 28th and 29th of January, 1942, Wilhelm Kissel and Richard Oberländer (technical manager of Daimler-Benz Werke 40, the main Berlin-Marienfelde plant) met with Reichsminister Todt and Sebastian Fichtner to discuss their proposed tank design. Fichtner pointed out that Daimler’s design had narrower tracks than M.A.N.’s; he also stated that he believed torsion bar suspension was superior to leaf spring suspension, as torsion bars allow greater internal width of the hull. The Daimer representatives disagreed with him on the superiority of torsion bars, as leaf springs allowed their design to be 200 mm (7.9 inches) lower than if it had used torsion bars, and leaf springs did not require the complicated shock absorbers that torsion bars did. Daimler believed that because their track had longer length in contact with the ground their design still had better ground pressure than the M.A.N. design, despite having narrower tracks. However, in actuality the track length in contact with the ground for both the VK30.01(D) and VK30.02(M) was the same, 3,920 mm (154.3 inches).

When recounting this meeting after the fact, Daimler representatives said that, “When compared to the competition, our tank with the longer suspension has improved performance when rolling over uneven terrain, crossing trenches, and climbing obstacles.” One interpretation of this statement is that the Daimler representatives were speaking of the aforementioned belief their tank had a longer track run than the M.A.N. design; however, another interpretation is that this statement seems to imply that Daimler had multiple suspension designs. It is possible that this is the explanation for why the unfinished chassis seen at the end of the war has return rollers, while no other depiction of the VK30.01(D) is shown to have them. The author puts forward the theory that the VK30.01(D), as it is most commonly depicted with no return rollers, is the “standard model”, while the unfinished chassis was to be built with the aforementioned “long suspension”, which must have necessitated return rollers by placing the roadwheels further from the drive sprocket.

During this meeting, the rear-mounted transmission was discussed at length; Fichtner was opposed to this feature as it could lead to tracks being thrown. (All the way back in 1928, the Germans had experienced this problem with the original Leichttraktor. They found that the rear-mounted transmission would cause the track to be “thrown”, or unseat itself from the drive sprocket. To correct this they instead went to front-mounted transmissions and stuck with them until the end of the war.) Daimler felt that wherever the transmission was mounted, there was no difference in the reliability and handling of the tank, as shown by Russian tanks. On this topic, Daimler-Benz representatives said, “Employment of the rear drive provides additional crew space and also a better slope to the hull front armor, which is especially important in preventing penetration of armor-piercing shells. If no option is possible for the choice of motor, our design also allows the installation of the Maybach [HL 210] motor. However, in basic principle, only our MB 507 and MB 503 motors will be proposed.”

The turret Daimler used was also discussed, with Daimler insisting on using the “OKH-Einheitsturm” (Oberkommando des Heeres Standard Turret), which reportedly Fritz Todt was in support of. It is never clarified exactly what the OKH-Einheitsturm is. Some sources seem to have assumed this meant the Panzer IV turret and associated 7.5 cm KwK 40, however this is certainly false, as from the start, the VK30 project was to use Rheinmetall’s 7.5 cm cannon. The Oberkommando des Heeres, or German Army High Command was not a designing office and would not have its name applied to anything other than for the purpose of official endorsement.

Further confounding this, the only other reference to the “Einheitsturm” is in Germany’s Panther Tank by Thomas Jentz, which indicates that it was to have been used on Krupp’s VK20.02(K) in late 1941/early 1942, mounting a “7.5 cm KwK 44”. Two 7.5 cm cannons used the designation “KwK 44”, and both came much later in the war. The first was the KwK 44 L/70, an improvement on the KwK 42 L/70 that would have been used in the Panther Ausf.F; the second was the KwK 44 L/36.5, the cannon that was mounted coaxially in the Maus. Although the latter would be the more reasonably sized given the context, neither gun is of the correct time period.

Einheitsturm may very well be the name for the turret designed by Daimler-Benz for the VK30.01(D), but the question of whether this turret design was approved by the OKH as a future standardized turret, as the name suggests, why it was chosen, how it came to be, and why no record of it exists apart from two off handed mentions, remains unanswered.

During the January 28/29th meeting, the Daimler representatives inquired as to the allowed weight of the vehicle, which Fichter told them was still 32 to 35 metric tons (even though M.A.N. had already exceeded this). Wilhelm Kissel also took this time to talk to Fritz Todt about the cooperation between M.A.N. and Daimler-Benz on their projects, which he felt was no longer beneficial. He emphasised that, “everything that is expected in meeting the design requirements derived from experience on the Eastern Front, is being met by the Daimler-Benz design.” Implying that involving M.A.N. in development was only holding Daimler back. Kissel also said that, should the Daimler design win the VK30 competition, Daimler-Benz was prepared to finish the design at their own expense. Fritz Todt agreed that the cooperation between M.A.N. and Daimler-Benz had outlived its usefulness and would allow the two firms to develop their designs separately. Following this, the February 2nd meeting between M.A.N. and Daimler was canceled.

Kissel had managed to convince Todt to allow the VK30.01(D) to go forward, and on February 2nd, Daimler’s design was finalized and deemed ready for mass production without change, much to Kniepkamp and Fichtner’s dismay. Daimler-Benz was approved to construct five prototypes, one with an MB 507 diesel engine, one with an MB 503 gasoline engine, and three with Maybach HL 210 engines. The first of these was projected to be completed in June of 1942. This is not to say that Daimler’s design had been chosen at this point, but Fritz Todt had allowed Daimler-Benz to go ahead with further development on their design without making radical changes.

The same day, February 2nd, Wilhelm Kissel wrote to Jakob Werlin (head of Daimler-Benz Munich) about his success, “Assuredly, you will greatly enjoy hearing that it was possible for me to convince the Reichsminister that a decision in favor of our new proposed tank is the correct one. When this decision is reached, the gentlemen from both the Heereswaffenamt [Wa. Prüf. 6] and M.A.N. will indeed be astonished.” A day later, M.A.N. would submit their finalized design as well. The winner of the competition would be chosen following a presentation of the two designs in Berlin on March 3rd.

On February 8th, Fritz Todt was killed in a plane crash; whatever plans he had for the VK30.01(D) went with him. However, much to Daimler-Benz’s fortune, the new Reich Minister for Armaments and Ammunition, Albert Speer, was also a proponent of their design.

On March 5th, 1942, Hitler, acting on the recommendation of Albert Speer, ordered Daimler-Benz to prepare for production of their design, giving them an order for 200 units. Hitler felt that the Daimler design was superior in almost every way, and particularly liked the fact that it used a diesel engine; he felt this was the way forward in tank design. Whether these views were entirely Hitler’s, or were seeded by Speer, is up for debate. At this time, the order for prototypes from Daimler-Benz seems to have been reduced to just two.

*These figures are rounded to the nearest fifth. They were found using the following formulae determined by the Kraftfahrt Versuchsstelle (driving test center) at Kummersdorf.
On-road fuel consumption: 8 liters per vehicle ton per 100 km
Off-road (moderate) fuel consumption: 11 liters per vehicle ton per 100 km
Calculations assumed the vehicle in question was running on 74 octane gasoline, however the Daimler-Benz design ran on diesel; meaning it would have been 15 to 20% more efficient than calculated.

Judgement

The results of the scheduled presentation of the VK30 designs in Berlin on March 3rd, 1942, have not been recorded by any available sources. Whether it occurred at all is unknown.

The scale model of the M.A.N. (left) and Daimler-Benz design (right), shown to Hitler on January 23rd. Source

As design work on the VK30 machines was finished and a winner needed to be chosen as soon as possible, Hitler had a special committee put together to weigh the advantages of both designs and suggest which should go into production. In charge of this committee was Oberst Wolfgang Thomale (OKH Inspector of the tank corps) and Robert Eberan von Eberhorst (professor at Dresden Technical University). The committee first met on May 1st, 1942, in the Bendlerblock building in Berlin, the headquarters of the OKH. Four meetings in total would be held, the subsequent three occurring on May 5th, 6th, and 7th.

Drawing No. Tu 16901 of the VK30.02(M), dated May 2nd, 1942, submitted along with M.A.N.’s proposal to the Panther Committee. Source: Germany’s Panther Tank by Thomas L. Jentz

There were two main considerations regarding which design would be selected. First was that a large number of the tank would need to be operational by the summer of 1943, and to facilitate this, production should start in December 1942. This requirement was felt to outweigh all others. The December 1942 deadline was supposedly set by Karl-Otto Saur (Albert Speer’s deputy) in a bid to win favor with Hitler by getting the new tank into production faster. The second consideration was that, in order to combat the numerical superiority of the enemy, the German machine needed to be of higher quality.

Both designs were capable of a top speed of over 55 kph (34 mph) and an on-road cruising speed of 40 kph (25 mph). Both designs carried the specified 7,5cm KwK 42 L/70 cannon with the same number of shells (79 rounds), and both designs incorporated the requested sloped 60 mm thick frontal hull armor. In fact, the armor of both tanks was nearly identical, besides differing angles of sloping the only difference was the M.A.N. design’s 40 mm (1.57 inches) of rear hull armor compared to the Daimler’s 50 mm (1.97 inch).

Comparison of the M.A.N. and Daimler-Benz designs by their stats on paper. While the Daimler-Benz design has a small advantage in armor, the M.A.N. design has a larger advantage in automotive capabilities. Table produced by Author.

Particular attention was paid to the advantages and disadvantages of transmission placement. The advantages of the forward-mounted transmission in the M.A.N. design were seen as:

  • Direct operation of the gearbox and steering (The Daimler-Benz design had to have a complicated series of linkages to allow the driver to control the transmission.)
  • The steering brakes could be adjusted from inside the vehicle
  • Less mud would be jammed up in the drive sprocket, as it would have more time to be shaken from the tracks on their return trip

Advantages of the rear-mounted transmission of the Daimler-Benz design were:

  • The heat, smell, and noise from the transmission would be as far away from the crew as possible
  • The driver and radio operator had more room
  • Space inside the fighting compartment was used more efficiently
  • The whole vehicle was lower (The hull of the Daimler-Benz design was 52 mm (2 inches) shorter than the M.A.N. design.)

Both designs would take nearly the same amount of time to construct once in production; the amount of work that would go into making one tank was projected as 1,063 man-hours for the Daimler-Benz design, and 1,078.5 for the M.A.N. design. Of these numbers, 351.5 man-hours would be required for assembly of the hull for the Daimler-Benz design, and 327 for the M.A.N. design. The M.A.N. design would require a special type of drill press to manufacture the hull.

Unfortunately, because Daimler-Benz had designed their own turret instead of using the one designed by Rheinmetall, as M.A.N. had done, they would not be able to have the turret in production by the December deadline. Additionally, the machine gun mount and optics of Daimler’s turret design were seen as vulnerable areas compared to the Rheinmetall turret. However, the final nail in the coffin for the Daimler-Benz design was the smaller turret ring. Because Daimler’s turret ring was 50 mm smaller in diameter than Rheinmetall’s, the latter turret would not fit onto the Daimler-Benz hull without significant redesign to widen the whole tank. Furthermore, the Daimler-Benz design was felt to too strongly resemble the T-34, which could lead to incidents of friendly fire. The forward-mounted turret was also seen as an issue, as the greater gun overhang increased the likelihood of impaling the gun barrel in the ground when going down hill, or catching it on trees or buildings. The M.A.N. design minimized this issue by putting the turret in the center of the vehicle. Finally, the M.A.N. design had greater operational range, provided a better firing platform on account of its suspension, used an engine that was already in production, and was more suitable for deep wading due to its sealed engine compartment. For these reasons, the “Panther Committee”, as it was known, unanimously chose the M.A.N. design.

Their decision was handed down to the chairman of the Panzerkommission, Dr. Ferdinand Porsche, on May 11th. This was also the date on which the name “Panther” was first recorded in regard to the project. The origin of the name is unknown, though Albert Speer later recalls in his book, Inside the Third Reich, that this was chosen to signify the new tank’s agility in comparison with the Tiger.

Hitler was informed of the Panther Committee’s findings in detail on the 13th of May. He felt that the rear-mounted transmission of the Daimler-Benz design was still superior, and that the 60 mm (2.36 inches) of armor on both designs was insufficient. He did concede, however, that getting the tank into production as fast as possible was the deciding factor, and that producing both tanks alongside each other would hinder this. Hitler stated that he would study the commission’s findings overnight and give his decision through his adjutant, Gerhard Engel, the next day.

Engel relayed to Porsche on the 14th that Hitler was in agreement with the committee’s findings, and that the M.A.N. design was to go ahead instead of the Daimler-Benz design. However, Hitler had stipulated that the frontal armor needed to be increased to 80 mm (3.15 inches). On May 15th, 1942, Fichtner placed a phone call to M.A.N. to inform them that they had won the contract, and of the increase in armor required by Hitler. It was also suggested that they consider Dr. Porsche’s suggestion of using a Kolben-Danek (ČKD) steering system, like the kind used in the Panzer 38(t).

Out of the Frying Pan and into the Fire

With M.A.N.’s Panther design going forward with the utmost priority, Heinrich Kniepkamp took personal charge of development. The design received the name Panzerkampfwagen V “Panther” and the Sonderkraftfahrzeug nummer (special vehicle number) Sd.Kfz.171.

On or around May 4th, one week before their design for the VK30 was chosen, M.A.N. had a final meeting regarding their design where the major details were reviewed. In addition to what has already been covered, in this meeting it was specified that:

  • There were 86 track links per side, and the width of the tracks would not prohibit transport by rail.
  • The transmission used a Maybach OLVAR 0640 12 16 gear drive.
  • The final point worth mentioning the author has been unable to determine the meaning of, other than that it relates to the transmission. “Spur gear side transmission doubly geared down, with sprockets of module 9 and 11. The middle tooth group was not required to be ground since it made no contact.”

At this point, the steering system that was to be used in the tank was undecided. It was assumed that a traditional clutch-brake steering system would be used initially. The reason for this change was that the companies that would be involved in the manufacture of the Panther did not have the proper equipment, specifically slotting machines, to cut the gears for the controlled differential type transmission. A portion of the 29 gears that made up each controlled differential were “hollow” gears, that is, the teeth were on the inside of the wheel, rather than the outside. This type of gear was significantly harder to make.

The transmission housing would be cast with steel of a strength of 60 kg/mm². Converted to megapascals, the most common unit of pressure used in describing tensile strengths, this is 588 MPa. Compare this to high strength steels, which range in the area of 750 to 850 MPa, and armor plate which goes above 900 MPa. The reason why the steel used in the transmission was so weak, relatively speaking, was to allow more units to be made. The weak drivetrain, already propelling a tank several tons heavier than it was designed for, and now made of lower quality materials, would plague the Panther throughout its service life. Any shrink holes that formed in the transmission housing from the casting process would be welded over and the whole casing would be heated and allowed to gradually cool, a toughening process known as annealation.

A conference was held on May 19th, 1942, at the Reich Ministry for Armaments and War Production. In this meeting it was determined that a majority of the facilities involved in manufacturing parts for the Panther tank would be those captured in France.

A conference with Hitler was held on June 4th, 1942, in regard to the new Panther tank. Hitler felt that by the spring of 1943, even the increased frontal armor of 80 mm (3.15 inches) would not be enough. He demanded that it be attempted to increase all frontal armor of the tank to 100 mm (3.94 inch) thickness. The same day, another meeting was held (presumably back at the Reich Ministry for Armaments and War Production, if the meeting with Hitler had not been there in the first place) between representatives of the four companies selected to build the new tank; M.A.N. of Nürnberg, Daimler-Benz of Berlin, Maschinenfabrik Niedersachsen-Hannover (M.N.H.) of Hannover, and Henschel of Kassel. It was determined that by the 12th of May, 1943, 250 Panther tanks must be available for combat. A model of the tank was displayed at the end of the meeting.

At some point during development, the L 600 C steering mechanism that was originally intended for the Panther had been dropped, in its place was the Einradienlenkgetriebe (single radius steering gear), also called the Maybach Double Differential. It is not known whether this steering mechanism is the same as the one insisted upon by M.A.N. that would allow for a pointed front hull, or if it was an entirely separate development. The Einradienlenkgetriebe is a steering mechanism completely unique to the Panther tank, having not been used on any other machine before or since. It combined two types of tank steering: the normal double differential and the controlled differential. “Single radius” refers to the fact that each gear has its own fixed turning radius (as opposed to other steering mechanisms, wherein the turning radius is variable depending on how much steering input is given). As there were seven forward gears, there were seven different turning radii, plus neutral steering.

A contract was awarded to Adler of Frankfurt am Main to deliver 50 Maybach OLVAR transmissions for testing in the Panther as an alternative to the Zahnradfabrik AK 7/200. In this configuration, the tank would have been known as Panther Model B, however the OLVAR transmissions were never installed.

In a meeting on the 13th of July, 1942, Paul Wiebicke insisted that the Einradienlenkgetriebe must be used from the start in all Panthers. When confronted with the possibility of this totally new and untested steering mechanism failing to work, he suggested that 60 clutch-brake steering systems should be built just in case, therefore they would be available to complete tanks if the Einradienlenkgetriebe turned out to not be ready.

The Panzerkommission met the next day, and again the Panther’s steering mechanism was discussed. They came to the conclusion that the first 100 tanks would have the interim clutch-brake steering system while production of the Einradienlenkgetriebe got underway. All tanks with clutch-brake steering were to be backfitted with Einradienlenkgetriebe by the end of April 1943.

M.A.N. hoped that trials of the new steering mechanism would be completed by mid-October 1942. Three different sets of gearing were put forward, the differences between them being the turning radius. The three setups would have given turning radiuses of 50, 80, and 115 meters (164, 262, and 337 feet) respectively, when in seventh gear. For speed and simplicity it was decided to only test the gearing that would give 80 and 115 meter turning radiuses. To test the two types against each other it was planned to make two interchangeable sets of gears for each of the first 20 to 30 steering units. In the final analysis, the 80 meter turning radius gearing was chosen.

M.A.N. had received a contract to complete an experimental VK30.02(M) chassis by August 1942, and a second, complete prototype by September. Both prototypes were made out of mild steel. The exact date these prototypes were finished is unknown; sources are divided as to whether the first was completed in late August or early September, but the latter seems more likely. Panther & Its Variants claims it was delivered at the end of September.

On August 3rd, Krupp, which had been in the process of designing the unrelated Panzerselbstfahrlafette IVd assault gun on the basis of their Panzerselbstfahrlafette IVc self-propelled anti-aircraft gun, was informed that the 8.8cm L/71-armed assault gun would no longer be based on its own unique chassis, but on that of the VK30.02(M), and should be redesigned accordingly. This would become what is known as the Jagdpanther.

On August 4th, M.A.N. announced that they would begin construction of the first prototype hull, and they requested that the foremen and chief operators from the Henschel, M.N.H., and Daimler-Benz plants visit M.A.N. in Nürnberg to familiarize themselves with the project.

The first prototype, VK30.02(M) Chassis Number V1, was finished without a turret. Instead, it had a box-shaped weight to simulate the turret. This machine was used for driving tests on the M.A.N. factory grounds in Nürnberg. The suspension of the V1 differed from all other Panthers in that the shock absorbers were mounted to the first and eighth roadwheel arms, as opposed to the second and sixth.


Illustration of VK30.02(M) Chassis Number V1 by Andrei Kirushkin

Due to unavailability of parts and for the sake of simplicity, the prototype was completed with a clutch-brake type steering unit. This was less efficient than the Maybach type, produced higher wear on parts, and did not allow the tank to neutral steer. Additionally, in place of the intended planetary reduction gear, this machine was fitted with a two-stage spur gear reduction of the final drive; the end result of a final drive reduction being the trade-off of speed for torque. It is unclear what steering system the V2 prototype used.

The only known photograph of the VK30.02(M) V1 undergoing trials at the M.A.N. factory grounds, seen here attempting to climb a rather impressive grade. Evidence of the vehicle’s descent into the pit, or perhaps a separate attempt at climbing out, can be seen on the far side. Source: Panther & Its Variants

The second prototype was a complete tank with turret. VK30.02(M) Chassis Number V2 mounted the 7.5 cm KwK 42 L/70 with an early, 220 mm (8.66 inch) diameter, single-baffle muzzle break in the Rheinmetall-Borsig turret. While similar to the muzzle break used by the 7.5 cm KwK 40 L/43 on the Panzer IV Ausf.F2, it was not identical. The V2 had apparently been delayed by the Rheinmetall turret not being ready in time. The turret housing was finished on September 16th, and final assembly of the turret was done at Rheinmetall’s Düsseldorf plant.

The turret used on the VK30.02(M) V2 was derived from the turret developed for the VK45.01(H2), the original Tiger tank. Back in May of 1942, it had a maximum width of 2.14 m (7 feet) which tapered to a frontal width of 1.84 m (6 feet). Excluding the cupola it was 770 mm (30.3 inches) tall. By the time the turret was built and mounted, it had grown to 790 mm tall (31.1 inches) and 2.30 m (7’7’’) wide, tapering to 2.104 m (6’11’’) wide. Increasing the height of the turret by 20 mm (0.79 inches) while also keeping the frontal plate sloped at 12° and the rear at 25°, meant that the turret also became 20 mm (0.79 inches) longer. The length would not be changed on production turrets, even when the frontal turret armor was increased to 100 mm (3.94 inches), meaning that the 20 mm of extra space needed was taken from the inside, instead of being expanded outward. Another feature of the prototype turret that would not be changed in the production model was the offsetting of the entire gun mantlet by 40 mm (1.57 inches) to the right of the centerline.

Inside view of the prototype turret mounted on the VK30.02(M) V2. The gunner’s position is to the left of the cannon and the loader’s to the right. The commander’s seat can be seen at the far left of frame. Source: Panzer Tracts 5-1

The most distinctive feature of the Versuchs-Turm (experimental turret) though, was the curved turret sides and bulge stamped into the left side of the turret to accommodate the cupola. The controls for the smoke grenade launchers were placed inside this bulge. The sides of the production turret would be widened to eliminate the cupola bulge; the layout of many of the interior components would also be changed.

View of the inside of the Versuchs-Turm from the loader’s position, facing the rear. The controls for the Nebelkerze (smoke dischargers) can be seen in the bulge under the commander’s cupola. The hatch to the left of frame is the main entrance and exit for the turret crew. Source: Panzer Tracts 5-1

When it was completed, the second prototype VK30.02(M) was sent to Kummersdorf proving grounds for official testing. The V1 was registered as IIN-2686 and the V2 as IIN-0687. “IIN” was the prefix for license plates registered to the cities of Nürnberg and Fürth. What is strange about this is that registered German military vehicles usually had a registration number with the prefix “WH” for the Heer (army) or “WL” for the Luftwaffe. Instead, the VK30.02(M) prototypes were registered as civilian vehicles in Nürnberg, the home city of M.A.N.

The hulls of the two Panther prototypes differed slightly from the production model. None of the hull plates were interlocking, as they would be on all Panthers that came after. The hull side plate did not extend past the rear plate at all. Between the 16 mm (0.63 inch) thick bottom of the hull and the 40 mm (1.57 inch) thick rear plate (reverse sloped at 30°) was a small 30 mm (1.18 inch) thick plate reverse sloped at 60°. On production vehicles this piece was eliminated, meaning the belly plate and the rear plate were directly connected to each other. The driver’s periscope was only 432.5 mm (17 inches) to the left of the centerline, on production vehicles it would be moved further out, to about 490 mm (19.3 inches) left of center line. The casting of the armored covers that went over the fans on top of the engine deck included an extension that encompassed the radiator filler cap, this would be eliminated on the production model. The drive sprockets on the prototypes were different to the production type. The dual exhausts shared a single horizontally mounted muffler, with a single exhaust pipe exiting at the center, just behind the engine deck. The roadwheels had 18 rim bolts each as opposed to 16. Finally, at the rear of the engine compartment was a single large fuel tank, the filler cap for this tank was to the left of the center line on top the engine deck.

VK30.02(M) V2 on trials, likely at Kummersdorf. Notice the ball-shaped muzzle break, drive sprocket, and clean-cut side armor plates. Source: Panther External Appearance & Design Changes
VK30.02(M) V2 on trials, likely at Kummersdorf. Notice the bulge on the side of the turret which accommodates the cupola, and also the ladder on the side of the hull. Source: Panther External Appearance & Design Changes
VK30.02(M) V2 on trials, likely at Kummersdorf. Notice the license plate held on with wire. Source: Panther External Appearance & Design Changes
VK30.02(M) V2 on trials, likely at Kummersdorf. Notice the narrow rear of the Versuchs-Turm, the extensions of the armored fan covers which encompass the radiator filler ports, the single exhaust pipe, and the rear license plate hanging from the exhaust. Source: Panther External Appearance & Design Changes
VK30.02(M) V2 on trials, likely at Kummersdorf. Source: Panther External Appearance & Design Changes
View of the engine deck of the VK30.02(M) V2 with all cover panels removed. The large single fuel tank in the rear (nearest to the camera) would be changed on the production model, with the filler port being moved to the right and the section of tank on the left being deleted. Source: Panzer Tracts 5-1

On account of the 80 mm (3.15 inch) thick frontal armor demanded by Hitler, the V2 weighed 43 metric tons – 8 tons over the 35 ton weight limit for the VK30. It was powered by a 650 hp Maybach HL 210 engine, giving it a power-to-weight ratio of just 15.1 hp/ton. This figure was 25% worse than the initial VK30.02(M) design projected. On the positive side, trials showed that there was less stress on the rubber roadwheel tires than was expected, and less stress on the torsion bars as well (16kg/mm square actual versus 20-22kg/mm square expected).

VK30.02(M) V2 on trials, likely at Kummersdorf. Source

The Panzerkommission met for the 11th time on November 2nd and 3rd, either at the 2nd Panzer Regiment’s training field in Berka an der Werra, or the nearby city of Eisenach. The following week a wide variety of experimental vehicles were to be demonstrated at Berka an der Werra — the “rough terrain” outpost of Kummersdorf — for Albert Speer and personnel of Wa. Prüf. 6. The vehicles slated to be present at the demonstration included VK30.02(M) V2, VK30.01(D), a VK36.01(H), a Panzer II with a Zahnradfabrik Electric Transmission, a Panzer III with Ostketten, a Zugführerwagen 40 (Panzer III with Schachtellaufwerk overlapping suspension), the Zugführerwagen 41 (Panzer III with rubber-saving roadwheels), two Henschel Tigers, one with a Zahnradfabrik 12E-170 Electric Transmission, two Porsche Tigers, two Panzer IIIs and two armored cars with with flamethrower equipment, a T-34, and a KV-1. A number of half-tracks, trucks, and tractors were also involved in the display, namely four Sd.Kfz.3s, an Sd.Kfz.10, an Sd.Kfz.11, two Radschlepper Ost, a Raupenschlepper Ost, a French Latil, and an Opel Blitz 3,6-6700 A.

The supposed presence of a VK30.01(D) at this demonstration is the only evidence for a Daimler-Benz Panther ever being built to a degree where it would be operable. Sadly, there are no known photographs of the vehicle selection at this demonstration which would confirm many details about the lost history of the VK30.01(D).

On the first day of demonstrations, Albert Speer drove the VK30.02(M) V2 for one and a half hours. He was highly complimentary of the tank’s handling. The trials showed that the differential worked well in rough terrain and that the tank turned fine without having to rely on brake steering. At this time, the V2 was temporarily equipped with a controlled differential discontinuous regenerative steering unit. This would not be the same as the Einradienlenkgetriebe, and may in fact be the L 600 C. The delegation from M.A.N. present at the demonstration stated they were satisfied with the performance of their prototype.

On the 4th of December, the first Einradienlenkgetriebe delivered by Henschel was installed in the VK30.02(M) V1. The performance of this vehicle with the new steering mechanism was not recorded. This was the last use of the VK30.02(M) as a developmental platform, as the Panzerkampfwagen V went into production in January 1943.

Daimler’s Requiem

Information regarding the development and construction of the Daimler-Benz design is frustratingly slim. Only bits and pieces exist that, when cobbled together, give a rough idea of the sequence of events following Daimler’s loss of the Panther contract. Unfortunately, many of Daimler-Benz’s files were destroyed at the end of the war, and much of what did survive fell into possession of the Soviets. While the Iron Curtain has now fallen, this information has still not escaped the Russian archives.

Following M.A.N.’s victory in the VK30 program, Albert Speer informed Daimler-Benz on the 20th of May that work on their design was to cease. However, they would be allowed to complete the two prototype machines that were already under construction. With M.A.N.’s design selected after all, the previous order for 200 Daimler-Benz tanks was withdrawn.

The loss of the VK30 contract was discussed by the Daimler-Benz board of directors on June 3rd, 1942. The following transcript of that meeting is from Germany’s Panther Tank by Thomas Jentz.
“Our proposal for the new tank was not accepted by the special commission established by Hitler. Instead they selected the M.A.N. design for large scale production, after the initial proposal from M.A.N. apparently was improved. During a meeting, M.A.N. had the opportunity to learn all the advantages of our proposal which they then took into consideration in their own design.
At first, the majority of the experts were impressed by our proposal. Even Hitler expressed his approval. But then, the commission consisting of Thomale and Eberan, decided against us for the following reasons:

  • The double torsion bar suspension from Porsche was chosen over our proposed leaf springs.
  • The MB 507 motor proposed by us can not be produced in the number required.
  • Our design requires a new turret. The turret for the M.A.N. design was already designed. The M.A.N. vehicle had front drive, our vehicle rear drive. Because of the rear drive our vehicle required a new turret design. It was admitted that the rear drive possessed advantages.

We are completing only two experimental vehicles, that positively will make a good impression. The two experimental vehicles are to be completed in June/July 1943. The entire tank should be completed since we can finally obtain the turret ourselves. We still have the contract to build these two prototypes and therefore we also want to demonstrate these as completed tanks.”

The same month, June 1942, the MB 507 diesel engine was installed in the first prototype. It is believed the first VK30.01(D) was completed about September, likely excluding any sort of turret. As was discussed in the previous section, it is reported that the Daimler-Benz Panther was present at Berka an der Werra in November of 1942, and that it competed alongside the VK30.02(M) prototype.

The fact that an operational VK30.01(D) existed no later than November is an apparent contradiction to Daimler’s own estimate of June or July 1943 as the completion date. It is possible this was the projected date for total completion of both the first and second prototypes, including turrets, which needed to be made from scratch.

If the VK30.01(D) prototype was in fact made to run at some point in 1942, then the question remains, why are there no photographs of it? While photographs of the VK30.02(M) prototypes are few in number, enough exist to give us a visual history of the vehicles. Only two photos remain of a VK30.01(D) prototype, both show it in an incomplete state without a turret and running gear, left outside the Daimler-Benz plant in Berlin at the end of the war.

A still image from a video survey taken by the western Allies of the Daimler-Benz Marienfelde plant after the end of the war. The unfinished VK30.01(D) hull is seen among other discarded weapons and vehicles. It is painted in RAL 3009 Oxidrot (oxide red) primer. The vehicle to the right of frame is the VK20.01(D), the earliest ancestor of the Daimler-Benz Panther. The field gun beside the VK30.01(D) is an 8cm Panzerwurfkanone 8H63, previously known as the PAW 600. To the left of the VK30.01(D) is the hull of a StuG III Ausf.G with the Saukopf gun mantlet. Source: Unknown

The quality of these photographs is poor, but with digital manipulation, more details can be brought out that show this hull is quite different to the original VK30.01(D) design. The most prominent feature is the presence of return rollers mounted on top of the leaf spring bundles. This has been the most vexing question raised during the writing of this article, and one which no credible source dares to expand on. While the interpretation regarding the January 28/29th meeting that the phrase “long suspension” is in fact talking about the length of suspension travel and not the length of the track in contact with the ground is very much grasping at straws, there is no other explanation for the change in suspension layout that is not based entirely in conjecture and even fiction.

In addition to the suspension, mudguards, and the slightly redesigned driver’s visor, which placed the periscope further forward than that of the mockups, other features seen only on this hull include an amorphous bulge on either side of the lower hull, just rearward of where the idler wheel would be, and a black-colored triangular extension of the hull atop the left side mudguard. The purpose of these features is not known; the only potential clue to their use is one of the only known blueprints for the VK30.01(D), which shows a linkage of the track tensioning system protruding up through the frontal glacis of the hull in the same area as the box

VK30.01(D) blueprint, notice the black linkage coming from the idler wheel at the front of the hull. Source
A lightened and cropped version of the first picture, showing the first of three return rollers and the bulge on the left side of the hull. Source
Photograph taken of the same hull from the other side. This angle more clearly shows the undocumented features of this hull, namely the box atop the left side fender, the front mudflaps, modified driver’s port, and suspension with return rollers. Also of note are the Panther tracks in the foreground; it is not known whether these were to be used on this prototype, or if it is merely a coincidence they are here. The hull of the vehicle to the left of frame seems to be that of another VK20.01(D). Source: Panther & Its Variants
An enhanced version of the previous photo. The three return rollers and unfinished suspension are easier to see.
Another still taken from the same film as the first photograph of the VK30.01(D) hull. The framework on the building on the right matches that seen in the first still. At the extreme right of frame is what appears to be the front right corner of the VK30.01(D) hull poking above a pile of rubble between it and the camera. Note at the extreme left of frame is the hull of an Sd.Kfz.8 Typ DB 10 half-track. Source
Overview of the bombed out Daimler-Benz Marienfelde plant taken from across the street. This photo seems to be from a later date as some of the rubble has been cleared and the scaffolding on the main building has been removed. Arrows have been drawn on the enlarged portion of the photo to show the Sd.Kfz.8 hull and what may be the VK30.01(D) or the VK20.01(III). Source: Daimler AG “Mercedes-Benz Classic”

The history of the Daimler-Benz Panther between November 1942 and June 1945 has been lost to time. While there is no direct evidence that the second prototype, which would have mounted the MB 503 gasoline engine, was ever completed, or even laid down, there is circumstantial evidence to suggest this may be the case. Daimler-Benz’s official production numbers for Panther vehicles is 545 for 1943, and 1,215 for 1944. These figures are including all vehicle types in the Panther family, for instance the 1,215 figure is a summation of the 1,175 Panthers and 40 Bergepanthers that Daimler-Benz produced in 1944. Daimler’s figures are perfectly in line with the actual production numbers confirmed by the author, with the exception that Daimler-Benz produced only 543 Panthers in 1943. This leaves 2 vehicles unaccounted for; the same number of VK30.01(D) prototypes Daimler intended to make.

Without knowing for certain when and how the change in suspension came about, it can not be taken for granted that the vehicle seen in the photos is the first prototype. Its incomplete state would indicate that some work had gone into the VK30.01(D) after the November demonstration in which the first prototype took part, whether this was construction of a second prototype or deconstruction of the first. The final fate of the Daimler-Benz Panther remains unknown.


Conservative reconstruction of the incomplete VK30.01(D) hull found at the Daimler-Benz factory in 1945 based off of photographs and supplemented with known features of the original design. The hull with return rollers is seen in photos to have the same mounting brackets for leafsprings as the original hull design, thusly it is drawn here with leafsprings.


Hypothetical reconstruction of the incomplete VK30.01(D) hull with return rollers, closely following the original design which lacked them. The retention of the same leafsping suspension suggests relatively unchanged running gear, merely lengthened to accommodate the return rollers, hence the author’s “long suspension” theory. Certainly this arrangement looks quite attractive, and would have greatly improved the VK30.01(D)’s vertical stepping ability — an area where it was outclassed by the VK30.02(M). All illustrations on this page by Andrei ‘Octo10’ Kirushkin, funded by our Patreon campaign.

Final Disposition of the Prototypes

With the Panzerkampfwagen V Panther in production, the two VK30.02(M) prototypes had served their purpose. What became of the VK30.02(M) V2 is not known, as there is no record of it past December 1942. The V1 prototype, on the other hand, did go on to serve a useful purpose as a suspension testbed. No written sources detail the post-1942 career of the VK30.02(M) V1, photographs are all that is left to tell the story.

Sometime in 1943 or 1944, the VK30.02(M) V1 was modified to replace its 18 bolt roadwheels with new Gummisparenden Laufwerke (rubber-saving running gear), all-steel roadwheels. These 800 mm (31.5 inch) diameter roadwheels were designed to save precious rubber, a resource that Germany was quickly running out of; they were to be used on both the Panther II and Tiger II, and eventually would also be used on the Tiger Ausf.E and Panther Ausf.G. The VK30.02(M) V1 was also fitted with Transportketten (transport tracks) and new drive sprockets and idler wheels. Transportketten were 660 mm (26 inch) wide tracks used on the Tiger and Tiger II to allow those vehicles to fit on railcars; these tracks were intended to be used as the main combat tracks for the Panther II, which was under development in 1943, aimed to replace the troubled Panther Ausf.D and standardize components with the Tiger II, then also under development. The drive and idler wheels used on the VK30.02(M) V1 test vehicle seem to be completely unique, they do not resemble those used on the Panther II or any other tank.

Without supporting documentation as to when this conversion was made, it is impossible to say for certain its purpose; however, the fact it is equipped with Gummisparenden Laufwerke and Transportketten, both features of the Panther II, would suggest that this was a testbed for that vehicle. This is contradicted by the fact that the only known photos of the VK30.02(M) V1 in this configuration come from 1944, a year after the Panther II was cancelled.

During a series of tests in 1944 at the M.A.N. plant, the VK30.02(M) V1 Testbed was fitted with a vibration measuring apparatus. This consisted of a bicycle wheel “idler” in contact with the ground, a vertical track for the idler to move up and down on so to stay in contact with the ground, a lever which reduced the input from the idler by 2:1, and a further 6:1 reduction device in conjunction with a vibration recorder. Several wires ran from the sensor to the inside of the tank, presumably to a recording device.

The VK30.02(M) V1 Testbed driving over a wave road in 1944. The single bicycle tire on a vertical track mounted to the side of the tank is a system for measuring vibration. Source: Panzer Tracts 5-1
Another shot of the above. The license plate seems to have fallen off between this shot and the previous one and has been stuck back on sideways. On the left mudguard appears to be a Wolfsangel, a rune emblematic of the 2nd SS Panzer Division; the purpose of its presence is not known. Source
Closeup view of the vibration measuring device. Source
What may possibly be a photo of the VK30.02(M) V1. Other Panther chassis used for developmental purposes were also fitted with the same type of turret-simulating test weight, but usually without the observation cupola. The fact that this tank has two headlights and an apparent foot step on the side of the test weight are in line with the VK30.02(M) V1, but without greater detail it cannot be said for certain. Source

Allied reports on the post-war evaluation of Henschel’s Tank Proving Ground in Haustenbeck mention what may be one of the VK30.02(M) prototypes. Apart from the incomplete E-100 and Grille 17, two Tiger IIs, a Jagdtiger, a Panther Ausf.G, and two VK30.01(H)s also found at Haustenbeck, it is recorded that, “Two tanks made during early German tank development are also in this area. They are of light armor plate and show distinct lines of the Mark IV and Mark V tanks. The salient feature is in the development phase of their suspension systems.” Unfortunately, photos of these tanks have not been found.

Sources

AFV Profile 10 Panzerkampfwagen V Panther – Chris Ellis and Peter Chamberlain, ~1972
Armor at War Series Panther cn7006 – Thomas Anderson and Vincent Wai, 1996
Germany’s Panther Tank: The Quest for Combat Supremacy – Thomas L. Jentz, 1995
Osprey Military Fighting Armor of WWII Panther Variants 1942-1945 – Hilary Doyle and Thomas Jentz, 1997
Osprey New Vanguard Panther Medium Tank 1942-45 – Stephen A. Hart, 2003
Panther vs T-34 Ukraine 1943 – Robert Forczyk, 2007
Panther & Its Variants – Walter J. Spielberger, 1993
Panzer Tracts No.5-1 – Thomas L. Jentz and Hilary Louis Doyle, 2003
Panther External Appearance & Design Changes – Roddy MacDougall and Martin Block, 2016
Inside the Third Reich – Albert Speer, 1969
https://warspot.ru/14561-panteri-predki
http://www.gizmology.net/tracked.htm
ETO Ordnance Technical Intelligence Report 288 – Henschel Tank Proving Ground, 24 May 1945
100 Jahre DaimlerChrysler Werk Berlin – Chronik 1902 – 2002
Correspondence between the author and staff of Daimler AG
Correspondence between the author and staff of Rheinmetall AG

The author would like to express the utmost gratitude to the staff of Daimler/Mercedes for their generous assistance in providing information.

Categories
WW2 German prototypes

Schwerer-Flammpanzer auf Jagdtiger (Flammanlage auf Jagdtiger)

Nazi Germany (1944-45)
Flame Tank – Design Only

The Germans were quick to exploit the devastating psychological effects of the flamethrower in the First World War with man-portable examples. Those were short-range devices that excelled at demoralizing the enemy and at clearing enemy positions. However, they were seriously limited by their weight, range and operational endurance for ‘flaming’ – a function of how much fuel it could carry. There is only so much a man can carry and, even in WW1, there were ideas for mounting flamethrowers onto armored vehicles. Armor would allow for close contact with the enemy to obviate the problem of range, the engine and platform would counter the flaw of a man not being to carry enough fuel, and the armor would ensure it was protected, unlike a man-portable version. In WW2, the Germans tried various vehicles as the mounts for flamethrowers, from the Panzer I and II up to and including the Tiger I. One of the lesser-known concepts though was the consideration of the Jagdtiger as the platform on which to mount a flamethrower.

Why the Jagdtiger?

It is hard to understand quite why the Jagdtiger was considered as a possible platform for a heavy flamethrower without a short review of the previous flamethrowing equipment operated by the German Army. Some Panzer I’s were modified to mount flamethrowers during the Spanish Civil War, and very early in World War II the Germans had mounted a man-portable flamethrower into the turret of a Panzer I (Pz.Kpfw.I Ausf. A), known as ‘Flammpanzer I’. These had been used in North Africa against the British but the very thin armor of the Panzer I left it vulnerable close-up to anti-tank rifle fire and even concentrated machine-gun fire. The short-range of the man-portable flamethrower and small fuel tank meant that not only did it have to get very close to be effective, but also had a very short flame time on target due to the small fuel capacity.

Flammpanzers I and II (Flamingo) showing the turret-mounted flame-projector on the Pz.1 and the front-wing mounted projectors on the Pz.2 Source: Jentz et al. (left)

An improvement in this regard was the Pz.Kpfw.II(f) also known as ’Flammpanzer II’, which found use on the Russian Front. Slightly improved in all regards, the Flammpanzer II was still vulnerable to enemy fire and had an inadequate flame duration and range. It would not be until the retrofitting of a motor-driven flame-throwing system on captured French Renault Char B1 heavy tanks that at least one of these concerns (the armor issue) was resolved. That vehicle, known as the Pz.Kpfw.B2 (fl), had abandoned the compressed gas cylinders used on the Pz.Kpfw.II(f) and adopted a motor-driven pump to provide the pressure required, using the same principle as a fire-fighting pump for projecting water. Although this did require a relatively low-viscosity flame fuel made from oil mixed with petrol, the pump was able to cope and propel burning fuel out to 40 to 45 metres. The drawback with mounting this system on the Char B though was obvious. It was a captured vehicle in limited supply, was also rather slow and, more importantly, did not provide a significant increase in range.

Two views of the front-mounted flame-projector fitted to the front of the captured French Char B1 (Pz.Kpfw.B2 (f)). Source: Jentz et al. via The Tank Museum, England

It was not until the Pz.Kpfw.III (fl), a flamethrowing tank based on the Panzer III, that an effective German flame tank was provided. Powered by a Koebe* HL II 40/40 1000/20 pump which, in turn, was driven by a two-stroke 28 hp Auto Union ZW 1101 (DKW) (1,100 cc) engine, the Pz.Kpfw.III(fl) could propel a jet of burning flame oil out to just 60 metres at a pressure of 1.52 to 1.72 MPa (15 to 17 atmospheres) and a rate of 7.8 litres per second. The fuel mix itself easily ignited by means of Smits’ glow plugs (Smitskerzen). Mounting this weapon on the Panzer III provided adequate armor and mobility. It was still not ideal however, and would only find limited use.

* Koebe was the firm of Hermann Koebe Feuerwehr-Geraete-Fabrik of Berlin, a manufacturer of fire-fighting equipment

Pz.Kpfw.III (F) Sd.Kfz.141/3 ‘Flammpanzer III’ in action. Source: Jentz and Doyle

Flammtiger

The obvious successor to the Panzer III as a carrier for flamethrowing equipment was not, as might have been expected, the Panzer IV, because the same faults found with the Panzer III were still there on the Panzer IV, most importantly a lack of sufficient armor. The range of the weapon guaranteed that any vehicle had to come to very close range with the enemy which left it vulnerable, especially on the flanks, to enemy fire. This was why heavy/assault tanks carried heavy armor and it is no surprise therefore that, for an assault flamethrower, protection could be provided in two ways. Firstly, by increasing the distance from tank to target – which meant a longer range flamethrower, and secondly, by increasing the armor on the tank itself. By the time this was being considered though, the Allies were already operating heavily-armored flamethrowing vehicles with a long range, such as the Churchill Crocodile. With up to 152 mm of frontal armor, a range of 140 m and carrying nearly 2,000 litres of flame fuel, the Churchill Crocodile was strides ahead of anything in the German inventory and should have come as absolutely no surprise to the Germans. They had, after all, captured some Churchill Oke flamethrower tanks after the raid on Dieppe in 1942, yet had done little work on the subject.

It was not until 5th December 1944 that proper consideration was given to a long-range, good-duration, heavy flamethrower on a well-armored chassis, when the topic came up in a conference with Hitler. Hitler was no stranger to the idea. He had, after all, pressed for the addition of not one, but two flame nozzles to be added to the Porsche Maus over a year earlier, pushing for a system with a range of 200 m. By the end of 1944, though, the Maus project was effectively over despite having a functional vehicle, there was no prospect of production restarting for it. The most heavily armored chassis in use and available at that time was that of the Tiger II. Tiger II hulls were at a premium at the time and production was focussed on both the tank version of the hull as well as the tank-destroyer version, known as the Jagdtiger, with the huge 12.8 cm gun.

Hitler’s goal was to put a heavy flamethrower onto a vehicle with enough frontal armor to be effectively immune to enemy fire and this meant very thick armor. This was the focus of the following meeting on 29th December 1944 and the heaviest armored vehicle available was the Jadgtiger, but only if a range of 200 m could be achieved, something which at the time could not be done.

Despite a following meeting on 3rd January 1945, where the extremely heavy armor was emphasized and that a figure of 250 mm was needed (the same as the front of the Jagdtiger’s casemate), more discussion was had but no designs or plans were forthcoming. The Jagdtiger, as it met the armor requirement, was the leading prospect for this new vehicle, even if those vehicles were at a premium and needed for their original role.

At a further meeting held on 23rd January 1945 by the Entwicklungskommission (tank development committee), Obert Crohn of Wa Pruf 6 presented a design for a new flamethrower. This design, like the Churchill Crocodile, used compressed nitrogen gas (going back to the original gas-propelled rather than motor-driven system) and could achieve the same range as that of the Crocodile, about 140 metres. How much the Crocodile system influenced that design is debatable although the similarities are interesting.

With this new system designed, a longer range was achievable, albeit not the 200 m demanded and with Jagdtigers in short supply, it was instead to create a prototype based upon the hull of a Tiger I Ausf E. Whether that Tiger I-based heavy flamethrower would ever have been developed further into an actual production vehicle on the chassis is unknown, just as is whether or not the Jagdtiger-based idea would be revised if the flamethrower had proven successful. As it was, neither project was ever built. The Tiger I-based system was ordered and parts sent for assembly, but the war ended before this had been assembled. Nonetheless, a concept of what a production version of that Tiger I-based vehicle could look like is possible.

The Tiger I-based option was worked on under the name Schwerer-Flammpanzer auf Tiger I’ (Heavy flamethrower on Tiger I), so the Jagdtiger-based option could be speculatively referred to as Schwerer-Flammpanzer auf Jagdtiger’ (heavy flamethrower on Jagdtiger).

Schwerer-Flammpanzer auf Jagdtiger: What Would it Look Like?

Knowing only that the Jagdtiger platform was considered for mounting this heavy flamethrower system, and there being no plans or drawings known to exist for it, it is not possible to know exactly what such a vehicle could have looked like had it ever been built.

An examination of the considerations at play during this period provides some important clues though. First is the gun, not the flamethrower nozzle but the actual gun on the Jagdtiger. This gun was a 12.8 cm Pak.44 L/55. A very potent gun capable of firing a 28.3 kg armor-piercing shell and penetrating around 200 mm of armor at a range of 2,000 m. The obvious desire for the Jagdtiger would be to retain this gun as it allowed for the destruction of the enemy at a very long-range rather than closing to close range for a flame-attack. Major-General Thomale, for example, understood the value of flamethrowers, especially those on small, light and maneuverable vehicles and bemoaned the idea of a flame system on a Tiger I as it was wasteful of the main gun.

That obvious advantage of keeping the main gun was fulfilled by the British on the Churchill Crocodile and exactly this consideration was given the Tiger I project – retain the gun and add a flamethrower.

Taking the Jagdtiger therefore, exactly the same consideration can be given to it. Retain the gun and add the flamethrower in place of the hull machine gun. This, on the face of it, gained the advantages of both ideas but had a couple of flaws. Firstly, the loss of the machine gun would leave the Jadgtiger with no secondary armament, as it did not have a coaxial machine gun like the Tiger I. Of course, for the Tiger I option, it was eventually selected to go without a turret anyway, so it was left in the same boat and to get around this problem a remote-controlled machine gun was fitted to the roof of the Tiger I hull. Conceivably, a machine gun could easily be added to the roof of the Jagdtiger too as it retained all of the usual features there.

The second problem of putting the flamethrower in the hull machine gun position and retaining the gun was space. There was simply no space inside the Jagdtiger in which to put the large-volume fuel tanks required of a flamethrower. The same problem had been considered on the Tiger I (with turret) and the same solution was apparent for both. The obvious route was the same one taken by the British, the towing of a fuel-carrying trailer. For the Crocodile, the nitrogen cylinders were fitted into the trailer along with the fuel and then it was piped through the tank to the nozzle at the front for projection. The trailer-option, however, was not adopted, perhaps because it was too vulnerable to fire or for want of developing a whole new trailer for it.

With no trailer option possible, this would leave a question as to where the flamethrower would be mounted. It could, of course, go in the hull replacing the machine gun, perhaps retaining a dummy barrel, but it could likewise have simply, and more effectively, been mounted inside the huge casemate. The massive mounting at the front which allowed the 12.8 cm gun to move could be repurposed for holding the flame nozzle, as this would be easy for the gunner (to the left) to operate and direct whilst at the same time retaining the existing machine gun for close defence. In the absence of any plans or any development of the Jagdtiger-based idea, it is not possible to know which of these might have been selected.

Jagdtiger damaged during a bombing raid on the Nibelungen works on 16th October 1944 affording a unique look inside showing the enormous interior of the casemete to be occupied by the 12.8 cm gun. Source: Frohlich and Schneider respectively

The one thing the Jagdtiger really offered, making it a good choice for this heavy flamethrower idea, was volume, it was simply huge inside. With the breech, mounting, and ammunition for the 12.8 cm removed, there would easily have been enough room for fuel tanks. For the Tiger I, for comparative purposes, it was to have its turret removed and still had space for a pair of 400 litre fuel tanks. Retaining its full interior volume, a Jagdtiger-based vehicle would have had even more space inside so more than 800 litres could easily have been carried. Any further speculation as to what a potential Schwerst-Flammpanzer auf Jagdtiger is perhaps best left to model makers.

System

The new flame-system which had been chosen is worthy of attention in any discussion over this potential vehicle. As previously stated, the system had gone back to using compressed nitrogen gas, and was to use special high-pressure fittings to raise the pressure available from them. The reason for going back to gas-propellant was a change in fuel. In order to reduce dispersion and in an attempt to get closer to the thickened mix used by the British, the old oil/petrol mix had to be thickened up and this meant that a pump could no longer be used. The system pressure on the Pz.Kpfw.III (f) operated at 1.52 to 1.72 MPa (15 to 17 atmospheres), and by changing to this high-pressure gas system, that was increased to 2.03 to 2.53 MPa (20 to 25 atmospheres). This, and the thicker fuel, meant the range was increased to about 140 metres with a burst delivering around 20 litres of fuel per second.

Crew

Given that this project received nothing more than some consideration with no plans, it is not possible to know how many of the original complement of 6 men (commander, gunner, loader x 2, driver, and radio operator) would be retained. Certainly, the tank, at a minimum, required the driver, radio operator and commander, and with no gun, did not need the 2 loaders. This means that at least 3 men would be needed, but the gunner is questionable depending on whether or not the flame unit was mounted in the hull or casemate. Assuming it would have been casemate mounted, the retention of the gunner would have allowed the commander to concentrate on commanding the tank whilst the gunner used the flame gun to immolate the target.

Automotive

As the vehicle was based upon an existing Jagdtiger hull, there were likely no changes made to the hull, save for whatever new armored cover arrangement might have been added around the casemate front around the flame nozzle. It would have retained the same running gear and the same 700 hp Maybach HL230 petrol engine with performance probably about the same, as if the large and heavy 12.8 cm gun was removed, it would simply be replaced with a couple of large fuel tanks instead.

Conclusion

The overall idea was not a bad one considering the goal was the production of a very heavily armored heavy flamethrower. Despite General Thomale’s preference for small and light flamethrowing vehicles, the use of them was limited to isolated enemy positions, as they were simply too vulnerable to enemy fire otherwise. A flamethrower on a Jagdtiger might sound incredible on paper, but the slow nature of the vehicle, the sheer size and removing the gun would have made it a very obvious target for enemy fire.

It is undoubtedly true that a flamethrower has some practical military value as well as making a huge psychological impact on an enemy force. This fact is reinforced by consideration in February 1944 from the Panzer Grenadier Division ‘Grossdeutschland’, which recommended the use of a motor-driven ‘howling siren’ to accompany the use of the flamethrower to maximise the demoralisation effect.

Regardless of whatever value such a system might have had for extensive flaming of a heavily defended enemy target, this was simply neither what the German Army needed in 1945, nor a type of combat they were undertaking. By this time in the war, it was a process of defensive combat and withdrawal. The Jagdtiger itself proved to be rather inadequate at its role despite the otherwise impressive armor and armament and reusing this chassis for a flamethrower was a project without a purpose. Such things were only pursued because Hitler had said so.

No Schwerer-Flammpanzer auf Jagdtiger was ever made or likely even drawn, but consideration of the chassis for this type of weapon system provides a special insight into both the functioning and the dysfunction at the top of German military command and vehicle design.



Jagdtiger with the main gun removed and replaced with a fake main gun to disguise the flame projector. No drawings of what a Flammjagdtiger could look like exist. Therefore the art is an impression only of what a casemate-based flamethrower might have looked like if it had ever been pursued.


No drawings of what a Flammjagdtiger could look like exist. Therefore the art is an impression only what a hull-mounted flamethrower might have looked like, in this case having to haul a trailer for additional fuel.

These illustrations were produced by Mr. C. Ryan, funded by our Patreon Campaign.

Specifications

Total weight, battle-ready >70 tonnes
Crew 4 ((Driver, Radio operator/hull machine gunner, Commander, Gunner)
Propulsion Maybach HL230 P30 TRM 700 hp Petrol engine
Speed 38 km/h (road)
Armament Heavy flamethrower – 140 m range
Armor Glacis 150 mm at 50 deg., lower front hull 100 mm at 50 deg., front hull roof 50 mm, casemate roof 40 mm, engine deck 40 mm, hull lower sides 80 mm vertical, hull upper and casemate 80 mm at 25 deg., casemate front 250 mm at 15 deg., casemate rear 80 mm at 5 deg. Hull rear 80 mm at 30 deg., front hull floor 40 mm, rear hull floor 25 mm

Source

British Intelligence Objectives Sub-Committee. (1945). BIOS report 1343: German Steel Armour Piercing Projectiles and Theory of Penetration. Technical Information and Documents Unit, London.
Chamberlain, P., Doyle, H. (1993). Encyclopedia of German Tanks of World War Two. Arms and Armour Press.
Doyle, H., Jentz, T., Sarson, P. (1995). Flammpanzer German Flamethrowers 1941-45, Osprey Publishing, UK
Doyle, H., Jentz, T. (2011). Panzerkampfwagen III Umbau. Panzer Tracts, Maryland, USA
Jentz, T., McKaughan, J. (1995). Elefant Panzerjager Tiger (P). Darlington Productions, Maryland, USA
Frohlich, M. (2015). Schwere Panzer der Wehrmacht. Motorbuch Verlag, Germany
Jentz, T., Doyle, H. (2008). Panzer Tracts No.6-3 Schwere Panzerkampfwagen Maus and E 100.
Schneider, W. (1986). Rarities of the Tiger family: Elephant, Jagdtiger, Sturmtiger. Schiffer Publishing, PA, USA
Spielberger, W., Doyle, H., Jentz, T. (2007). Heavy Jagdpanzer: Development, Production, Operations. Schiffer Military History, PA, USA
US War Department. (May 1945). Intelligence Bulletin Vol. III No.9. War Department, Washington, USA
War Office. (26th July 1945). Technical Intelligence Summary Report 182 Appendix F

Categories
WW2 German prototypes WW2 Swedish prototypes

Räder-Raupen-Kampfwagen M28 (Landsverk 5)

Sweden (1928-33)
Light Tank – 6 Prototypes

An article by Wilhelm Geijer and Leander Jobse

The Räder-Raupen-Kampfwagen M28 (Eng: Wheel-Cum-Track Tank M28), also known as the Landsverk 5, was one of the first German tank projects after World War I. According to paragraph 171 of the Treaty of Versailles from 1919, the German Army and German companies were forbidden to develop tanks. However, nine years after the treaty was signed, the development of the M28 started in high secrecy. Five or six of these vehicles were built in various configurations and examined by both the German and Swedish Armies, but did not enter service with either of them.

Background

On 3 April 1926, graduate engineer (Dipl.-Ing.) Otto Merker, then working at the Schwäbische Hüttenwerke, part of the company Gutehoffnungshütte (GHH), filed a patent in France concerning designs of wheel-cum-track tractors. During the two following years, he would improve and refine his designs until 1928, when the wheel-cum-track vehicle (the Räder-Raupen Fahrzeug) was ready to be produced. It was designed to act as the basis for a tank intended to be produced by the subsidiary AB Landsverk in Landskrona, Sweden.

Two designs for a wheel-cum-track tractor, patented by Otto Merker in April 1926. Source: Brevet d’invention No. 631.839.

The full name of GHH was Gutehoffnungshütte, Aktienverein für Bergbau und Hüttenbetrieb (Eng: Joint Stock Association for Mining and Metallurgical Business), based in the city of Oberhausen (North Rhine-Westphalia, Germany) with a specialization in mechanical engineering. Landsverk, then known as Landskrona Nya Mekaniska Verkstads Aktiebolag (Landskrona New Mechanical Works Joint Stock Company), had originally been a foundry focusing on various civilian applications of metal works. By 1920, the company was on the brink of bankruptcy. Seeing an opportunity, GHH bailed them out and gained 50% of the company’s stocks in the process.

After 1920, GHH managed to acquire more stocks and owned 62.8% of Landsverk in 1925. These stocks were registered by another subsidiary, N.V. en Handelsmaatschappij Rollo, a Dutch company acquired by GHH in 1920. A Swedish law from 1916 prohibited foreigners from owning more than 20 percent of a company, but the Landsverk articles of association were based on an 1895 contract.

These factors allowed GHH, who also owned the majority of MAN AG at the time, to circumvent the limitations on tank development in Germany set by the Treaty of Versailles through setting up armored vehicle development in Sweden. This use of subsidiaries and foreign companies to circumvent the treaty, as well as the cooperation with the USSR, was already suspected by the Royal Swedish Army Materiel Administration’s artillery department in the early 1930s.

Name

The Räder-Raupen-Kampfwagen M28, meaning ‘Wheels-Tracks-Fighting vehicle Model 1928’, is sometimes also referred to as ‘GHH-Fahrzeug GKF’. In Sweden and within Landsverk, it was known as the ‘Landsverk 5’, or L-5 for short. The idea of a wheel-cum-track system already emerged in Germany during the early 1920’s when Joseph Vollmer developed a system based on a Hanomag tractor, utilized by the Czechoslovak-built Kolohousenka. Merker could have been inspired by Vollmer’s system, although it is also possible that he was influenced by the British, who had started testing wheel-cum-track systems mounted on various vehicles around the same time.

Chassis equipped with the 77 hp engine and hydraulic wheel system. Note the presence of rear fenders and headlights. Photo: alternathistory.com

Swedish Tank Acquisition

In December 1928, Swedish authorities officially established requirements for a future tank:

  • Maximum weight of 12 tonnes
  • Armor to stop 37 mm cannon fire
  • Armament consisting of both a cannon and a machine gun
  • Good mobility in Swedish terrain, an average speed of 20 km/h on road and half that in relatively difficult terrain

By this point, Sweden’s entire tank force consisted of just ten strv fm/21s (alternatively known as strv m/21s), and a small number of foreign vehicles acquired for trials. Furthermore, military spending had been drastically reduced as a result of the defense resolution of 1925. For these reasons, acquiring the largest number of vehicles possible with available assets within a relatively short time frame was stressed. The Swedish government had previously granted SEK 400,000 for this purpose.

Based on international trips to tank factories and trials of foreign designs, it was realized that no foreign tank available on the open market was suitable for Swedish circumstances at the time. Moreover, indigenous tank production was seen as a major advantage in terms of readiness for a potential military conflict. As such, Sweden turned to its own industry. In 1930, there were three companies within Sweden that could provide the military with a new tank. These were Morgårdshammars Mekaniska Verkstad AB (Morgårdshammar’s Mechanical Works Joint stock company), AB Landsverk, and AB Bofors.

The first of these, Morgårdshammars Mekaniska Verkstad, could provide an indigenous design which had been in development since 1927. This development was headed by the Austrian Major and tank theorist Fritz Heigl, famed for his publication ‘Taschenbuch der Tanks’ (Eng: ‘Handbook of Tanks’). Bofors and Landsverk, on the other hand, relied on German companies for design work. These companies were Krupp AG and Maschinenfabrik Esslingen respectively. Both Landsverk and Maschinenfabrik Esslingen were subsidiaries of GHH at the time. Krupp was, via two decoy companies, the largest stockholder of Bofors and these arms manufacturers actively cooperated in the development of various projects during the interwar years. In the case of the Bofors proposal, the tank in question was actually Krupp’s Leichttraktor design. This was an evolution of the LK II which was in service with the Swedish Army as the lightly modified strv fm/21. The Leichttraktor was interestingly equipped with a turret produced by Landsverk, the competitor of Bofors and Krupp in this case.

One of the Bofors (Krupp Leichttraktor) prototypes as a monument – the fate of a vehicle without a future. Photo: Yuri Pasholok, via warspot.ru

Design

The design of the M28 was unconventional overall. The engine was mounted in the front left of the vehicle in a u-shaped frame. A cooler was placed in front of it. The driver sat directly to the right of the engine. In an elevated hatch, three visors were located. It could be folded open to the right side of the vehicle. The rolled homogeneous armor on the vehicle was of mixed construction, being both bolted and riveted. Its thickness is unknown, although it was most likely between 8 to 13 mm thick, as with the production models offered to Sweden. This would be adequate against small arms fire, but certainly not against cannon or anti-tank gunfire.

The vehicle could also be driven from the back by a second driver whose seat was located in the rear right. He was covered by an elevatable hatch, in which a machine gun was installed. Above the machine gun, three square-shaped visors were placed. On the left side of the back, an access door was installed.

The M28 which was sent to the secret Soviet-German Kama proving grounds for testing, the protrusion at the front left of the vehicle is an air intake. Photo: Landskrona minnesbanken

Engine

Either five or six vehicles, numbered 1-6, were built but differed a bit from one another. Whether the sixth vehicle actually existed or was even planned is uncertain due to contradicting sources (this is further detailed below). The first three prototypes, 1-3, were powered by a Benz-50-PS 4-cylinder gasoline engine and was fitted with a 70 l fuel tank. This engine had a displacement of 4160 cm3 and a compression ratio of 4.75. It consumed 14 kg of fuel and 0.4 kg of oil per hour at cruising speed. It had a maximum output of 52 hp at 1950 rpm.

The other three prototypes, 4-6, had a 70-PS-NAG-D7P 4-cylinder gasoline engine and an 85 l fuel tank installed. It had a displacement of 3620 cm3, a compression ratio of 5.5, fuel consumption of 18 kg per hour and oil consumption of 0,6 kg per hour at cruising speed. The maximum output was 77 hp at 3400 rpm. The gasoline was pumped into the carburetor by an electric IMCO-Autopuls-12-V-Pumpe (pomp). Besides the standard fuel tank, an additional reserve can with a volume of 30 l could be brought along.

A Typ K 45 gearbox produced by ZF Friedrichshafen AG was installed. This gearbox was equipped with a multiplication device, a so-called ‘Maybach Schnellgang’, which provided the vehicle with four forward and two reverse gears in total. Changing from forward to reverse gear took 4-5 seconds. Driving on wheels, the early vehicle could reach a speed of 46 km/h, but only 23 km/h on track. The cruising range was 180 km on wheels and 80 km on tracks.

From Wheel to Track and Vice Versa

Changing from wheels to tracks was performed by lifting devices on the sides of the tank. Vehicles 1-4 had an electric lifting system installed, together with four 12 Volt batteries, 5 and 6 had a hydraulic system installed. With these systems, the wheels could be lowered or lifted 36 cm, resulting in a ground clearance of 15 cm between the tracks and the ground. Total ground clearance between the hull and the ground in the tracked mode was 40 cm. For the later type with the revised lifting device, the transition from tracks to wheels or the opposite could be made in just 20 seconds.

Previous wheel-cum-track vehicles were generally designed in such a way that switching from wheels to tracks or the opposite took a considerable amount of time. By being able to perform this process in just a few seconds, and from within the vehicle, the wheeled mode could be employed not only in regions that were known to possess large amounts of good roads but instead anywhere suitable. The wheeled system could also function as a jack for the vehicle, something which could have been very practical for performing maintenance to the running gear or repairing a damaged track.

The wheel-cum-track system had the additional advantages of decreasing wear on the running gear while also lowering running costs by decreasing both maintenance work and fuel consumption. In addition to this, the increased speed and subsequent increased tactical, as well as operational mobility provided by the wheeled mode, was considered important in combat scenarios of the day as stalemates were sought to be avoided based on experience from the First World War. In addition to this, speed was considered to be more important in terms of protection than armor.

If the lifting system did not work, for example due to a technical failure, the wheels could also be manually lifted. When manually performed, lifting or lowering the wheels took four men around five minutes.

The presence of the wheeled system did, however, have its drawbacks in the form of increased overall width and weight, both of which would be troublesome in terrain, while also limiting hull width. In the case of the M28, the total width was 2.4 m but the distance between the outer edges of the tracks was only 1.6 m. This would limit the equipment and ammunition which could be carried. To partially address the width and weight issues, the wheeled units were designed in such a fashion that they could be removed in around six hours.

Front and rear photos of the M28 where the three rear vision blocks can be seen. Photo: zhuanlan.zhihu.com

Suspension

The wheels used cantilever springs. A cantilever spring is a flat spring supported at one end and holding a load at or near the other end. The suspension consisted of semi-elliptic leaf springs. Ten small road wheels were located on each side, gathered in two units of four and one unit of two. In order to reduce noise, some of the suspension components were covered by rubber and a type of coating from Ferodo, a British friction product manufacturer.

The metal tracks had a width of 20 cm, and a length of 12 cm. 66 track links were located on each side. The full weight of the vehicle was roughly 7 tonnes, which resulted in a ground pressure of 0.85 kg/cm2. The vehicle was maneuvered by a steering wheel via a special type of planetary transmission, a development of a Cletrac transmission. Rather than applying full braking force to the inner track during a turn, this transmission only reduces the power output to said track instead of completely cutting power. This resulted in the vehicle having a much smoother turning process than other vehicles of its day. A turn radius of 3 m within the inner track could be achieved using this system. If necessary, the inner track could be fully braked in order to perform tighter turns. The wheels were steered by a worm gear.

Braking while driving on the tracks was done with an outer-band brake, meaning that brake band is wrapped around the outside of a brake drum which will brake when tightened. While driving on wheels, an internal-band brake system was used, meaning that the drum is pressed on from the inside. The wheels were made of steel and equipped with pneumatic tires, although bulletproof tires seem to have been used as well. The wheelbase had a length of 2.8 m, while the complete chassis had a length of 4.38 m. On wheels, the chassis would reach a height of 1.48 m. As mentioned, the total width of the vehicle was 2.4 m, and the distance between the outer edges of the tracks was 1.6 m. The complete chassis of the early type without superstructure weighed 5.3 tonnes, the later type weighed 5.4 tonnes.

Turret

The commander and gunner were both seated in a centrally mounted turret. A six-sided cupola for the commander was installed on top with a visor in each side. This cupola could presumably be opened to the rear in order to provide increased visibility and access, just as on the mockup. Furthermore, two visors were placed facing upwards on top of the cupola. The commander and gunner could enter through a hatch in the back of the turret.

Armament

The primary armament of the M28 consisted of a 37 mm gun equipped with a semi-automatic breech. It had a depression of 10 degrees and an elevation of 30 degrees. To the left of the cannon, a coaxial 7.92 mm Dreyse machine gun was installed. It could be disconnected from the main gun which allowed for a depression of 15 degrees and an elevation of 35 degrees. Two optics were installed in the front of the turret, one for the main gun and one for the machine gun. An additional 7.92 mm Dreyse machine gun was installed in the rear driver’s hatch. This gun had a traverse of 20 degrees to each side, a depression of 5 degrees and an elevation of 77 degrees, potentially allowing it to be used as an anti-aircraft machine gun, although it is unclear if it was specifically designed for this purpose. The ammunition complement consisted of 200 37 mm shells and 2000 7.92 mm rounds in total. It should be noted that the primary armament seems to have never been installed, as all images depicting the front of the turret lack the 37 mm gun. The large protrusion at the front of the turret appears to be a shroud of some sort, presumably present to protect the gun from damage.

M28 with the rear driver’s hatch and machine gun at high elevation. Photo: valka.cz

Building and German Testing

A total of either five or six vehicles were built between 1929 and 1930 by Maschinenfabrik Esslingen. In order to retain secrecy, this production was labeled as farming equipment. A full-scale mockup was also constructed in affiliation with these vehicles. One of the early models with a complete armored body and turret was sent to Kama tank proving grounds in the USSR in 1930. The Kama proving grounds were located near Kazan. The name Kama was a combination of Kazan and Malbrandt, Malbrandt being chief engineer and responsible for the trials taking place at Kama. The proving grounds were a result of the Treaty of Rapallo, signed in 1922 between Germany and the then SFSR, which was not only intended to improve economic cooperation but military cooperation as well. The existence of these proving grounds was kept top secret as it did violate the Treaty of Versailles from 1919.

Designs like the WD Schlepper, Großtraktor, and Leichttraktor were tested at Kama, and so was the M28. During the tests, it became clear that it was underpowered and the suspension overloaded, which caused problems with the reliability of the systems, so the armored superstructure and turret were removed. After that, it performed reasonably well, but the Germans had lost their interest in this vehicle. When the collaboration between the USSR and German army ended in 1933, the vehicle was taken back to Germany and scrapped shortly after. What happened to the other vehicles is unknown, but it is highly unlikely that any chassis survived past the Second World War.

Demonstrations for Swedish Delegations

The first information regarding the M28 reached Swedish military authorities in the form of a confidential message to a lieutenant Elliot at the Royal Army Materiel Administration’s artillery department. It was reported that only a chassis had been produced so far. The fact that Germany was banned from tank production by the Versailles Treaty was well known. While the matter was subsequently shrouded in secrecy, captain Gösta Bratt, who was experienced with engines, was allowed to inspect and drive the tank in Germany.

The L-5 chassis, as it was referred to, was demonstrated to Swedish representatives on a number of occasions between 1930 and 1931. Demonstrations were primarily held with the later 77 hp engine and hydraulic system equipped chassis, without the hull and turret. Mobility was found to be more than sufficient and steering was easy to perform, even in sharp downward slopes. In the wheeled mode, a maximum speed of 80 km/h (49.7 mph) forward and 25 km/h (15.5 mph) backward could be attained. Additionally, upward slopes of around 40 degrees could be traversed without using full engine power. This was of course without the additional weight and instability brought by the armored body.

The running gear was generally liked, but the effectiveness of the semi-elliptic leaf spring suspension was not seen as sufficient, although improved suspension types were already being considered by this point. The construction of the wheeled units was regarded as being sufficiently robust for field use. Other features that were particularly acclaimed were the effective transmission, powerful engine, and silent running. The designer considered the advanced transmission, which allowed for reduced power output to the inner track during a turn, to be overly complex and that it would be advantageous to not include this feature in the production model. The Swedish delegation, on the other hand, viewed it as a significant advantage in Swedish terrain. While the pneumatic tires which were demonstrated were seen as suitable for peacetime conditions, their suitability for combat was doubted. For combat use, other types could replace the pneumatic tires. Semi-solid tires, which were offered by Landsverk for the production models, or bulletproof ones were considered for this purpose.

The previously mentioned issues with total and hull width respectively were however constant concerns. At the time, the maximum width of a tank suitable for Swedish terrain was considered to be 2 m, 0.4 m less than that of the displayed chassis. There was however consideration made on this point, namely that such a width would still be suitable for Swedish forests. A protecting framework could be fitted which would have protected the wheeled units, although this would not automatically increase mobility in dense terrain. Moreover, the 1.6 m distance between the outer edges of the tracks meant that stability could also become an issue in uneven terrain.

Another problem was the lack of armor protection in the opinion of Swedish officials, only 13 to 15 mm of frontal armor in the case of the projected designs. This could be addressed in the case of the fully tracked vehicle, as the weight saved by removing the wheeled units could be used to increase the frontal armor to 25 mm. Some statements doubted whether armor protection below 30 mm for the most vital areas was even acceptable and that the armor of the fully tracked variant should be improved without increasing the total weight of the vehicle beyond 9.5 tonnes.

Firepower was also criticized, despite meeting the original requirements, as only one weapon could generally be used to engage a target at a time. While the hull machine gun was an exception to this, as it would not be operated by the turret crew, it could only provide a limited arc of fire.

Despite these negative factors, the displays resulted in mostly positive reviews. The general performance of the tank was considered to meet and in some cases exceed the previously mentioned requirements and the vehicle was seen as a modern tank at the time.

Profile view of the M28 in its wheeled mode. Photo: valka.cz

Swedish Consideration

Landsverk’s offer to Swedish authorities actually differed from the L-5 in the state that it was demonstrated. Two variants were offered, both a wheel-cum-track design as well as a fully tracked model. These were known as BT.150 I and OT.150 I respectively. They differed from the original in a number of ways, among them, that they would use a rear-mounted 150 hp Maybach engine. A Scania-Vabis model was originally planned, but no suitable engine from this manufacturer was available. The vehicle would be around 0.5 m longer and some steering systems were to be altered. The tracks would be wider and the leading wheel would be placed higher up while the suspension system would be improved. Total weight of this projected type was 8.4-8.9 tonnes. Both of the offered designs moved the fourth crew member from the rear of the vehicle to the front, next to the driver. The fully tracked vehicle was intended to be equipped both with a hull mounted machine gun as well as radio equipment, whereas the wheel-cum-track design would feature either a hull machine gun or a radio. These projected characteristics generally align with what the development process resulted in, namely the L-10 and L-30 designs.

By 1931, the envisioned organization of a Swedish tank company consisted of 18 tanks, a number which Sweden did not possess. Moreover, what tank types were available, such as the strv m/21-29 (upgraded strv fm/21) and strv fm/28 (Renault NC27), were mostly obsolete by this point. Because of these factors, the tactical requirements and capabilities of modern tanks could not be properly assessed. This stressed the acquisition of a fully developed and modern vehicles within a short time frame.

As a result, only acquiring the fully tracked model was seen as an attractive option. Acquiring only this variant would have also allowed for a wider hull to be used while decreasing the overall width as the wheeled system would not be protruding beyond the sides of the hull. This would have increased stability as well as cross-country mobility while allowing for increased armor protection. The enhanced tactical and operational mobility provided by the wheel-cum-track design was however appreciated and purchasing one vehicle in this configuration would allow for extensive field trials and consideration to be performed with this type of vehicle. The potential to use the same vehicle model both as a fully tracked tank and as a vehicle with mixed propulsion was also seen as advantageous.

The increased speed but decreased protection of the wheel-cum-track design meant that a different tactical approach would be applied to the wheel-cum-track model. There were suggestions to use mixed units with fully tracked versions as the first line of an advance, while tanks in the wheeled mode would follow as guard tanks, and as such, be better able to react thanks to their higher top speed, like massing on a strong point or performing a local counter-attack. The wheel-cum-track tanks would also be able to support flanking recon or combat units or protect columns on the move. A tank with mixed propulsion was also considered suitable as a command tank. As the direct combat value of the wheel-cum-track design was not significantly worse than that of a fully tracked vehicle, they would be able to perform conventional combat roles as well. Moreover, as the wheeled units could be removed, it was possible to negate the issues with weight and total width which otherwise hinder this type of wheel-cum-track design.

More radical approaches were also explored, where tanks with mixed propulsions systems were seen as a potential replacement for armored cars. This built on the fact that the tracked system would allow cavalry units to pass difficult terrain and road obstacles while at the same time being more potent in the combat role. Logistical services like repair work and maintenance would also be aided by the fact that cavalry and tank units would share the same vehicle types. These advantages would, of course, be offset by the considerably increased cost of wheel-cum-track tanks compared to conventional armored cars. This view of mixed propulsion designs generally aligns with the opinion of Hauptmann Streich, who acted as a spokesperson for the Kraftfahr division of the German Waffenamt. He stated that a wheel-cum-track vehicle would be more suitable as a reconnaissance vehicle, rather than as a conventional tank.

The Sixth Vehicle – Author’s Theory

In historical writing and documents, there seems to be an inconsistency as to whether five or six vehicles were built. While German sources always seem to mention six vehicles, Swedish Army documents sometimes mention that only five vehicles were built.

The German-Soviet military cooperation was highly secret. This could mean that a sixth vehicle could have been kept secret from the Swedish Army and sent to Kama without them knowing. That would not only explain why the Swedes talked about five vehicles, but also why they never tested the vehicle with installed armor and armament. It is never even mentioned in Swedish sources that armor and armament existed. As such, it is very likely that the only vehicle that received armor and armament was secretly sent to Kama, with the Swedish army left unaware of its existence.

Conclusion

The greatest feat of the M28, or L-5, was serving as the catalyst of Swedish tank development, which would be headed by Landsverk until the 1950s. Trials of this vehicle proved largely positive and directly influenced the decision of the Royal Army Materiel Administration to place an order for the further evolved L-10 and L-30 designs in October 1931. While the purchase of a prototype of the newer type was considered, the limited funds and time frame rushed the acquisition process, resulting in a full purchase of the new designs. As for the competing tanks, the Bofors design proved to possess certain inherent design flaws. The Morgårdshammar design on the other hand, while displaying some positive features, could never be presented in physical form, and its head designer had by this point passed out due to disease. Meanwhile, the L-5 could mostly satisfy and in some cases exceed the requirements set up by Swedish authorities in 1928, and was thus the logical project to invest in. The development of these Landsverk designs would continue in Sweden as Otto Merker was employed at Landsverk directly in 1929, being tasked with creating a tank development division. He was appointed head of this division the following year. The establishment of a foreign subsidiary in the form of AB Landsverk allowed the German industry to gain experience with armored vehicle design throughout the 1930s in relative secrecy. Said experience was subsequently applied to help create the German armored force and its advanced designs as they existed in the lead up to the Second World War.

Drawing of the Landsverk BT.150 II from ~1930, one of the evolutionary stages between the L-5 and the following L-30. Photo: Krigsarkivet, special thanks to Karl Blomster for providing the photograph.


Illustration of the Räder-Raupen-Kampfwagen M28 or ‘Landsverk 5’ produced by Andrie Kirushkin, funded by our Patreon Campaign

Specifications

Dimensions 4.38 x 2.4 m (with wheels, 1.6 m body) x 1.48 (chassis only, on wheels) meters
Total weight, battle ready Aprx. 7 tonnes
Propulsion (TE and TM) (1-3) Benz-50-PS, 52 hp. (4-6) 70-PS-NAG-D7P, 77 hp.
Speed (road) 46 km/h (wheels), 23 kph (tracks)
Armament 37mm Gun
2x MG Dreyse 7.92 mm
Total Production 5 – 6

Sources

Die gepanzerten Radfahrzeuge des deutschen Heeres 1905-1945. Walter J. Spielberger, Hilary L. Doyle. Motorbuch Verlag, Stuttgart, 2002. p.94-99.
Safehaven: The Allied Pursuit of Nazi Assets Abroad, Martin Lorenz-Meyer, 2007, University of Missouri Press, p.10-11.
Paul Reusch und die Gutehoffnungshütte: Leitung eines deutschen Großunternehmens, Christian Marx, Wallstein Verlag, 2013.
The Secret School of War: The Soviet-German Tank Academy at Kama, Ian Johnson, MA thesis, Ohio State University, 2012.
Treaty Of Versailles, paragraph 171.
Merker, O. (1926). French patent No. 631.839. Paris, France: Ministère du Commerce et de l’Industrie.
Krigsarkivet, Arméförvaltningen, Artilleridepartementet, Konstruktionsavdelningen, Vol: F I:5
ASJ Landsverk, Lars von Rosen, Löddeköpinge: Sprinter AB/Maskinskyddarna, 2005, p.84
PANSAR Nummer 2 2014, Christer Badstöe
PANSAR Nummer 3 2014, Christer Badstöe
PANSAR Nummer 3 1982, Putte Hallberg
www.landskronaminnesbanken.se


Categories
WW2 German prototypes

Demag D II ‘Liliput’

ww2 German half-tracks Nazi Germany (1934-36)
Unarmoured Half-Track – At Least 3 Completed

The D II series of experimental half-tracks arose from the German Army’s pursuit of motorization in the years preceding the outbreak of the Second World War. Following successful trials with prototype designs that utilized the half-track principle in the late 1920s, semi-tracked trucks and prime movers became an integral component of this overarching drive for greater strategic and tactical mobility. Capable of achieving high speeds on roads as well as traversing difficult cross-country terrain, these vehicles appeared to be an excellent means of motorizing the German Army (Reichsheer). Convinced by these many advantages, the Heeres Waffenamt (Army Ordnance Department) assigned one of their most talented engineers, Heinrich Ernst Kniepkamp, the task of overseeing the development of a range of different half-tracks to fulfill the various needs of the German Army.

Having already approved the development of several designs capable of hauling heavy loads of up to five tonnes or more, in 1934 the Heeres Waffenamt initiated work on a smaller design that would be more suitable for towing lighter infantry guns and anti-tank guns. In response to these requirements for the Kleinster geländegängiger Ketten-schlepper (smallest cross-country tracked towing vehicle), the Demag firm produced small numbers of three consecutive prototype half-tracks: the D II 1, the D II 2, and the D II 3.

Known by their diminutive appellation ‘Liliput’, these comparatively small half-tracks nevertheless employed a whole host of innovative technological features that would go on to find widespread use throughout the Second World War. However, despite numerous incremental improvements across the three permutations of the D II series, the final D II 3 design still required further refinement before it could be considered suitable for series production. As a result, the overall design of the D II 3 continued to be gradually revised between 1937 and 1938, until it evolved by way of the interim D 6 into the final D 7. Classified as the Sd.Kfz.10 1-tonne half-track by the Heer, over 10,000 of the D 7 half-tracks would be produced from 1938 until the end of the Second World War.

In light of the ubiquity of its descendants, the D II 3 was a significant stage in the development of German semi-tracked prime movers. Even though the early D II designs appear to be far removed from the future Sd.Kfz.10, the underpinnings of a reliable workhorse had been established by the time the D II 3 was produced in 1936. As such, these obscure machines (of which we know very little) represent an important chapter not only in the development of German prime movers but also in the German Army’s quest to fully motorize its forces; a goal that, contrary to Nazi propaganda, would never be achieved.

A D II 3 half-track demonstrating its off-road capabilities. This machine was intended to be a mobile lightweight towing vehicle, with the versatility to perform well on paved roads or rough terrain. Consequently, it was designed to use a torsion bar suspension on both the tracked section of the running gear and on the front road wheels. In order to determine the best features, the D II series were tested with two types of tracks, as well as pneumatic tires or solid rubber tires on the front wheels. Seen here with all-steel tracks and solid tires, this D II 3 is unique in that it appears to have had a camouflage scheme applied to the hull. Consisting of two colors separated by stripes of a third darker color, this style of application does not conform to the usual Buntfarbenanstrich (a multi-colored scheme comprising three camouflage colors) that adorned many German military vehicles of the early 1930s.

Solving an Old Problem: The Motorisation of the German Army

Following Germany’s defeat at the end of the First World War in November 1918, the fledgling Weimar Republic inherited a strategic conundrum that had bedeviled generations of German military planners: how could the German armed forces defend Germany’s vast frontiers to both the east and the west with an army that was primarily reliant on railways for its mobility? Worse still for the German generals, the stipulations of the Treaty of Versailles compounded Germany’s vulnerability by placing size restrictions on the size of the military and banning the use of much of the latest military technology, including tanks. Confronted with this perennial German predicament and many hostile neighbors, the Reichsheer aimed to solve this problem by cultivating a highly mobile professional army that could rapidly respond to enemy incursions and form the nucleus of a resurrected German army capable of conducting its own offensive operations. In order to realize these strategic aspirations, the Reichsheer needed to enhance its tactical mobility. This, in turn, required one essential ingredient: the motorization of the German Army.

Correspondingly, significant emphasis was placed upon procuring motorized transportation for the Reichsheer, particularly in the form of tractors to tow artillery, in order to ensure that Germany’s limited military assets possessed the mobility to make a difference on the battlefield. These efforts culminated in the Kraftfahrüstungsprogramm (Motorisation Programme) formulated by the General Staff during 1927 and 1928. According to this initiative, the Reichsheer would specify its automotive requirements and provide technical specifications for designs that would be able to fulfill its needs. Whilst the 1920s saw many developments in this field, the Weimar Republic’s clandestine attempts to rearm in defiance of the Treaty of Versailles were accelerated with the accession of Adolf Hitler as German Chancellor in January 1933. Under the Nazi Party, which was vehemently opposed to what was perceived as the emasculating and unjust dictates of Versailles, plans to rebuild and motorize the Reichsheer were given greater priority and would eventually receive considerably more funds for research and development.

Among the many experiments in motorization undertaken by the Weimar Republic and continued by the Nazis was the development of three-quarter tracked vehicles (commonly known as half-tracks) for the purposes of carrying loads and, more importantly, towing artillery. Encouraged by earlier successes with these vehicles, Waffen Prüfwesen 6 (Wa Prüf 6), the sub-division of the German Army’s ordnance department responsible for the development of tanks and motor vehicles, initiated the creation of a light, medium, and heavy class of three-quarter tracked vehicles for the Reichsheer in 1932. At first, these vehicles were identified in accordance with their load-carrying capacity, but they were later reclassified to reflect towing weights of 5 tonnes, 8 tonnes, and 12 tonnes respectively. This reorientation originates from the conceptualization of these vehicles as prime-movers for the German Army’s various artillery pieces and trailers.

One of the products of this push for the motorization of the Reichsheer was the one-tonne three-quarter tracked vehicle. Although the initial requirements for three-quarter tracked vehicles prepared by Wa Prüf 6 in 1932 had not called for anything with less than 5 tonnes of towing capacity, there were plenty of anti-tank guns and infantry guns in development during the 1930s that would benefit from motorised towing, but which did not require a tractor with a 5-tonne towing capacity. Therefore, in order to provide prime movers for these indispensable constituents of German infantry formations, Wa Prüf 6 expanded the range of three-quarter tracked vehicles in 1934 to encompass a design with a one-tonne towing capacity. It was due to this imperative of motorization that the rather odd-looking Demag D II came into being.

The Demag D II 1 towing a 3.7 cm Pak anti-tank gun (left and an ammunition trailer (right). The trailer is most probably a Sd.Ah.32 used for transporting 3.7cm Pak, 7.5cm Le. IG, and 15cm s.IG 33 ammunition. Similar photographs exist of the Demag D II prototypes demonstrating their ability to tow 2cm Flak anti-aircraft guns. Although poor quality photographs (see Panzer Tracts 22-1 for better quality images), they show the unconventional appearance of the D II 1 and the rubber-padded track links associated with many of Kniepkamp’s designs. Due to the space taken up by the rear-mounted engine, the D II 1 was only capable of carrying four men. Sources: valka.cz & Forum.axishistory.com

The Dark Ages: The Genesis of the One-Tonne Half-Track

Whilst the overarching narrative recounting the mobilization of the Reichsheer is relatively well-known, the more intricate details pertaining to each particular vehicle are, by contrast, exceedingly scant. Nowhere is this more apparent than in the all-too-typical case of the one-tonne half-tracked vehicle, of which there are no surviving primary source records from either Demag or Wa Prüf 6 concerning its early development and production. Historians of the Medieval period may resent the ‘Dark Ages’ paradigm, but it is an apt term to describe the loss of information regarding the history of many interwar German military vehicles.

Consequently, the only comprehensive source available that outlines the early history of the one-tonne three-quarter tracked vehicle is a report compiled after the war in June 1946 by the British Army of the Rhine (BAOR). Entitled ‘German Semi-Tracked Vehicle Development from 1934 onwards’, this document provides a detailed overview of the history and the technical features of most of the German three-quarter tracked vehicles developed before and during the Second World War. However, the fact that the information in this report was primarily derived from post-war interviews with relevant personnel from the design firms and Wa Prüf 6, who did not have access to their records, means that it can contain significant errors and omissions. In the case of the one-tonne three-quarter tracked vehicle, the BAOR report contains only a brief synopsis of the production and technical features of the trial vehicles. Faced with this barren documentary record, there is little that can be said about the events leading up to the completion of the first Demag D II 1 sometime in 1934 or 1935.

Piecing together the evidence that is available, it is probable that the one-tonne half-track started development in 1934 as part of an effort to create a light prime mover that could advance at high speeds along paved roads and negotiate rugged terrain. The idea that the one-tonne three-quarter tracked vehicle was envisaged as a towing vehicle for light artillery, such as the leichtes Infanteriegeschütz 18 (le. IG 18) or the 3.7 cm Panzerabwehrkanone (3.7 cm Pak), is supported by a myriad of photographs showing trials vehicles hitched to these guns and their ammunition trailers, as well as the wartime use of their successors in this exact role.

Having established a need for this lightweight towing vehicle in 1934, Wa Prüf 6 contracted Demag AG, a crane manufacturing company based in Wetter an der Ruhr, to produce a series of trial vehicles (Versuchs-Fahrzeuge) incorporating their desired technical features and adhering to the prescribed specifications. Although Demag was a large industrial concern specializing in heavy equipment such as cranes and steam locomotives, this appears to have been their first project involving the development of half-tracked vehicles. Unfortunately, there is no information revealing why Demag was chosen to design these trials vehicles, or whether there were alternative concepts considered for this role. Whatever the wider story behind the early stages of the one-tonne half-track, between 1934 and 1936, Demag designed and produced a series of distinctive three-quarter tracked vehicles known as the D II, all of which employed several novel and unique technical features.

An excellent view showcasing the poorly optimized internal layout of the D II 1. Thanks to this overhead view, it is possible to appreciate the vast space consumed by the BMW 6-cylinder petrol engine. This design decision left little room for accommodating crew members and their various accouterments. In contrast to the previous photographs of the D II 1, this example has been equipped with the all-steel track links which do not have any rubber pads. Source: valka.cz

Micro Machines: The Development of the D II 1 and D II 2 ‘Liliput’

The first incarnations of the D II are immediately recognizable due to to their diminutive size and unconventional appearance. It is thanks to these characteristics that this series of machines received the peculiar moniker ‘Liliput’, an adjective (spelled ‘Lilliput’ in English) that denotes an object or person of extremely small size. Originating from Jonathan Swift’s famous eighteenth-century novel Gulliver’s Travels, in which Lilliput is an imaginary island inhabited by miniature 15 cm tall people, the term entered the European lexicon after this popular novel was translated into different languages. Whilst it may seem strange for a German military vehicle to be referred to by this esoteric label, the term ‘Liliput’ was sufficiently well-known in contemporary Europe that it became the name of one of the smallest semi-automatic handguns ever produced, the 4.25 mm Liliput Pistol, which was designed and manufactured by Waffenfabrik August Menz in Germany between 1920 and 1927. It is unknown how this term came to be attached to the Demag D II, but it appears to have been a contemporary name that aptly captures the strange appearance of these tiny machines.

Asides from its noteworthy name, the first variant of the Demag D II series developed between 1934 and 1935, the D II 1, also incorporated a number of unusual technological innovations. Whereas the other German semi-tracked vehicles mounted the automotive components onto a traditional chassis frame, the D II 1 encased all of these parts inside a unique lightweight hull. This novel approach to the construction helped to ensure that the machine would remain as light as possible, thus increasing its maneuverability and cross-country performance.

These performance characteristics were enhanced by Kniepkamp’s revolutionary torsion bar suspension, fitted to both the front axle as well as the tracked section. This worked in conjunction with the interleaved road wheels to provide the D II 1 with excellent mobility across challenging terrain, not to mention relatively fast speeds on paved roads. Although these features do not seem particularly remarkable in light of their widespread employment in later German designs of the Second World War, the Demag D II 1 was one of the first three-quarter tracked vehicles to use such an advanced suspension system successfully.

Kniepkamp’s penchant for cutting-edge technology and his preoccupation with speed, mobility, and weight are also evident in one of the types of track fitted to the D II 1. Alongside orthodox unlubricated pin cast steel track links intended to prioritize off-road traction, the D II 1 was also tested with lubricated needle-bearing track links, each of which carried a rubber pad. These track designs were viewed as a compromise between steel and rubber tracks, the former permitting higher speeds on road, with the latter being more suitable for off-road activity and more durable. By equipping German half-tracks with lubricated rubber padded tracks, Kniepkamp hoped to retain some of the beneficial performance and noise-dampening qualities of the rubber tracks, without sacrificing all of the resilience afforded by steel tracks. Although it appears to be the case that different track designs were still being evaluated at the time when the D II series was being tested, the lubricated needle-bearing rubber padded tracks had become a standard feature on all major German three-quarter tracked vehicles by the beginning of the Second World War.

Whereas the technical and automotive attributes of the Demag D II 1 fulfilled the brief for a light cross-country vehicle, other aspects of the design left something to be desired. Chief among these limitations of the D II 1, at least among those that are apparent without having access to any detailed testing reports, was the placement of the 1.479 litre 6-cylinder 28 hp BMW 315 engine. In another example of defying normal expectations, the engine of the D II 1 was not located in a separate compartment at the front, but was instead installed at the right rear of the hull, where it took up most of the space inside the rear compartment. As a result, there was room for only a driver and three additional men, with little space for extra stowage. For a vehicle designed to tow guns and carry their ammunition and crew complements, the lack of internal volume was a significant shortcoming that could only be rectified by a radical rearrangement of the internal layout of the hull.

One of the two known photographs of the Demag D II 2. Seen here crossing a trench, the D II 2 has been fitted with cast steel track links, which were known to provide better cross-country mobility than the rubber-padded alternatives. Curiously, there is also a triangular attachment of unknown purpose fitted to the front wheel’s hub. The many similarities between the D II 1 and the D II 2, such as the rear-mounted engine, the torsion bar suspension for the front wheels, and the hull construction, are readily apparent in this photograph. The civilian number plate ‘IY-02247’ seen on the front of the vehicle appears to have been used for all of the D II prototypes. Source: valka.cz

Sometime after the D II 1 was completed, the D II 2 was finished in 1935. In many respects, the D II 2 remained the same as its predecessor. It maintained the exact layout, engine, and suspension used in the D II 1, with the only major difference being the addition of an extra road wheel to the tracked suspension as well as a corresponding increase in track length. Other than the provision of a canvas cover to protect the driver from the elements, there were no more significant differences distinguishing the D II 2 from the earlier D II 1.

Consequently, by the end of 1935, Wa Prüf 6 was in possession of two lightweight compact towing vehicles capable of moving their light artillery. In the case of the D II 2, this translated into a vehicle capable of towing up to 600 kg, despite only weighing 2,560 kg fully laden. Moreover, it was able to attain a range of 250 km and a top speed of 50km/hr on roads, as well as scale a grade of 24 degrees unloaded or 12 degrees loaded. However, there were also significant shortcomings to these early designs which necessitated continued development by Demag.

An extremely rare photograph of the Demag D II 2 showing the extra fourth road wheel added to the suspension. Given the presence of both civilian and military observers, as well as the guide flags in the foreground, this D II 2 appears to be participating in some kind of training exercise or demonstration. It has been fitted with the lubricated rubber-padded tracks and a canvas cover over the cab to protect the driver from the elements. From this angle, it is also just possible to see the towing hitch and the rear-mounted exhaust muffler. Further in the background, there is a Sd.Ah.32 ammunition trailer, which is one of the loads that the Demag D II was designed to tow. Source: forum.axishistory.com

Towards the Sd.Kfz.10: The Demag D II 3

In 1936, the third and final incarnation of the D II, the D II 3, was assembled by Demag and delivered to Wa Prüf 6 for testing. In this guise, the D II came to more closely resemble the final shape of the mass-produced D 7. The original layout was discarded in favor of a more traditional setup, with the engine placed at the front in a separate compartment, whilst another road wheel was also appended to the suspension. Along with the conspicuous bulbous front fenders, these alterations to the D II 3 resulted in an appearance that bore a much closer resemblance to the later Sd.Kfz.10.

The D II 3 fitted with all-steel unlubricated tracks and pneumatic front tires. Compared to its predecessors in the D II series, the D II 3 had a more traditional layout with an engine at the front and the rear area reserved for passengers and cargo. Close examination of the photo shows a spare wheel attached to the rear, four rifles stowed behind the cab, and a couple of stowage boxes along the side. The radiator grille, large front fenders, and bug-eye headlamps give this machine a similar appearance to the later Sd.Kfz.10. However, the torsion bar suspension seen here fitted to the front wheels was a remnant of the earlier designs that would not be carried over to the D 6 and D 7. Source: valka.cz

However, the modifications to the D II 3 were not merely superficial aesthetic details. By replacing the BMW 315 engine with a larger 1.971 liter 6-cylinder BMW 319, the D II 3 was slightly more powerful than its predecessors. In addition to this, the relocation of the engine to the front of the vehicle improved cooling, thereby reducing the stress on the engine. Furthermore, the greater internal volume in the rear compartment meant that the D II 3 was able to transport 6 men in total, including the driver. For a vehicle intended to transport gun crews, this was a considerable upgrade to the design that increased its utility on the battlefield.

An overhead view of the Demag D II 3 highlighting the improved internal layout. By relocating the engine to the front of the vehicle, Demag created a rear area more conducive to carrying gun crews and their equipment. There was space for four passengers (as well as a driver and co-driver in the cab) and sufficient room to allow for stowage boxes to be attached along the sides. Source: valka.cz

The suspension also underwent several notable alterations. The solid road wheels of the D II were replaced by five road wheels of a new 6-holed variety. Coupled to a larger idler wheel that was mounted close to the ground, the extra track contact area provided by this refined suspension improved flotation on soft terrain, thus ameliorating the cross country mobility of this machine.

Another crucial evolution to the D II 3 design was the substitution of rollers in the place of teeth on the front-mounted drive sprocket. By using rollers, the friction between the track links and the sprocket was decreased. This reduction in resistance allowed the D II 3 to attain higher speeds and was to become a staple feature of later German three-quarter tracked designs.

In the same way as its forebears, the D II 3 was trialed with at least two different track designs, as well as two kinds of front wheels. In terms of tracks, this consisted of a familiar all-steel design alongside Kniepkamp’s lubricated rubber-padded tracks. These tracks could be combined with either pneumatic tires of a type similar to the D II 1 and D II 2, or a solid rubber variety. Unsurprisingly for an experimental vehicle like the D II 3, the photographic evidence is sparse and, due to the quality of surviving photos, difficult to interpret. However, photographs show that both types of tracks and front wheels were equipped on the D II 3, and seem to suggest that the different tire designs were tested in combination with both track variants.

An unusual photograph of a D II 3 in service with the Heer. This example has solid rubber front tires in place of the pneumatic versions used by the earlier D II prototypes and some D II 3s. Alongside these road wheels are all-steel tracks enveloping the distinctive six-holed road wheels. The flag-shaped object mounted next to the left side fender is a flag staff, a metal frame used to hold various pennants and flags that would help to identify the specific unit that the vehicle belonged to. Although these were a common feature on pre-war half-tracks, they were dropped from new production vehicles during the early stages of the Second World War. Source: forum.valka.cz

If the technical features of the D II are relatively well-documented by the BAOR report, production figures for these earlier vehicles are more opaque. According to the British, 38 D II 3 were completed by Demag. However, this claim is not confirmed by any surviving German records from the time and does not accord with the usual practice of producing trial vehicles in small series of one to five examples. This suggests that this statement in the BAOR report may be one of its many errors, but without the original German records, no definitive answer can be obtained. In either case, it is clear that in spite of the considerable improvements, the Demag D II 3 was an experimental vehicle that required further development in the eyes of Wa Prüf 6.

A D II 3 parked in front of two Panzerattrappen (dummy training tanks created on the basis of passenger cars). This particular specimen has solid front wheels fitted in combination with rubber-padded tracks. These tracks would have provided a faster, quieter ride on the paved areas in this courtyard compared to all-steel track links seen on other examples of the D II 3. The unfolded windshield shows two turn signals protruding from either side. These would later be relocated to a slightly lower position on the side of the hull on the D7. Source: valka.cz

Waste Not, Want Not: The D II 3 as a Testbed

Despite their shadowy existence in both the documentary and the photographic record, German prototype vehicles rarely enjoyed a quiet life. Rather than allow their experimental machines to languish in storage, many of the German trial vehicles ordered by the Heeres Waffenamt saw later use as testbeds for new concepts or technology. The Demag D II 3 was no such exception to this rule.

Even before the end of 1935, the Heeres Waffenamt had already presented a report outlining the tactical advantages of creating self-propelled 2 cm Flak guns on the basis of existing half-tracks. The report noted that due to the greater muzzle velocity and the superior penetration of the 2 cm Flak 30 anti-aircraft gun compared to other weapons of this caliber, it was not only an effective defense against air attacks but could also be employed to protect marching columns against surprise tank attacks. Taken by the merits of this idea, the D II 3 and D 6 experimental half-tracks were used to test a superstructure able to mount a 2 cm Flak 30 with 360 degrees of traverse, which would go on to be used on the mass-produced Sd.Kfz.10/4 anti-aircraft half-track.

Generally, such experiments mentioned in the documentation are devoid of photographic evidence, but every so often, stray photographs are published which illuminate these forgotten chapters of a particular vehicle’s career in service. In the case of the D II 3, there are at least two photographs confirming that at least one of the D II 3 experimental chassis fitted with solid rubber front tires and all-steel tracks was used to test this idea.

The D II 3 fitted with a trial superstructure for mounting the 2 cm Flak anti-aircraft gun. There are many similarities between this vehicle and the Sd.Kfz.10/4 produced in 1940. Chief among them are the loading ramps protruding from the front of the D II 3 and the small cable pulleys located just behind the driver’s cab. These would be used to load and unload the 2cm Flak gun from the rear of the halftrack, should it be desired to emplace the gun in a static position. Strong resemblances between this vehicle and the Sd.Kfz.10/4 can also be seen in the design of the folding sides, which have four bins attached to either side for carrying one magazine of 2 cm ammunition. Also, note that this D II 3 is using the solid front wheels rather than pneumatic tires and the all-steel tracks. Source: valka.cz

Close examination of these photographs reveals many similarities between the design of this trial superstructure and the standard style used on the Sd.Kfz.10/4, such as the four ready bins for one twenty-round Flak 30 magazine attached to the folding sides. Puzzlingly, the D II 3 testbed also has several features that were not fitted to Sd.Kfz.10/4 produced in 1939, but which did become standard in 1940. These include the loading ramps protruding from the front of the vehicle and the cable rollers just behind the driver, which were intended to allow the 2 cm Flak 30 to be dismounted from the half-track so that it could be emplaced in a concealed position on the ground.

Unfortunately, it is difficult to say any more about this experimental vehicle due to the lack of additional evidence. It is not even clear when this trial machine was modified in this manner, although it is probable, given its role as a testbed, that the conversion was completed between the production of the D II 3 in 1936 and the date at which the first orders for the Sd.Kfz.10/4 were issued in May 1939. Nonetheless, this example of reusing a prototype machine exemplifies the importance of the D II series in establishing the design parameters for many of the 1-tonne half-tracks that would see successful wartime service.

Another photograph of the D II 3 with the experimental superstructure for mounting a 2cm Flak gun. Examples of this superstructure were also fitted to Versuchs-Serie D 6 and 0-Serie D 6 half-tracks for testing. Source: Unknown

Stepping Stones: The D II in Retrospect

By the end of their development in 1936, the D II series of prototypes had established the foundations for a half-track design capable of meeting the specifications for a lightweight cross-country towing vehicle outlined by the Heeres Waffenamt in 1934. Although the D II 1 and D II 2 had many peculiar characteristics that were later dispensed with, they also pioneered several ingenious features that would be carried through to the mass-produced D 7, most notably the torsion bar suspension and the substitution of a hull construction in place of the conventional chassis frame. When the positive aspects of the early D II machines were amalgamated with numerous improvements introduced in the D II 3, the basic outline of the future Sd.Kfz.10 became fixed in shape.

Even so, the external similarities between the Sd.Kfz.10 and the final incarnation of the D II can be misleading. There would be multiple adjustments to almost every single facet of the existing design before its finalization as the D 7 in 1938, including changes to the engine, front axle, and road wheels. Nevertheless, In spite of these many modifications distancing the D 7 from the D II 3, these earlier vehicles still performed an important role in establishing the basic parameters and characteristics for their successors.

Consequently, the D II series must not be perceived as an evolutionary dead-end, but as a key step in the history of the development of the ubiquitous Sd.Kfz.10. Whilst none of the D II prototypes have survived to this day, their influence can still be appreciated through the mass-produced D 7, which is as prolific in present-day collections of German military vehicles as it was on the battlefields of the Second World War.

Soldiers posing with their solid rubber-tired D II 3. The opened bonnet provides a small glimpse into the engine bay, at the front of which is the radiator for cooling the BMW engine. Markings have been stenciled onto the side of the hull, but unfortunately it is not possible to discern their meaning. Usually, such markings were applied to trucks and half-tracks to remind crews of their weight, towing capacity, and other important specifications. The background does not furnish many clues as to where this photograph was taken, but the front of a Panzer I can be seen poking into the background. Source: valka.cz

Bibliographical Comment

The lack of surviving documentation concerning the history of the Demag D II series of vehicles means that the BAOR Report is still the primary source of information regarding these half-tracks. For those unable to access this report, Panzer Tracts 22-1 is an essential resource for further reading into this topic. As well as quoting directly from the BAOR report, this Panzer Tracts volume also highlights possible errors and provides several photographs of the D II that have not been published elsewhere. In addition to this, the coverage of the later D 6 and D 7 developments has revolutionized our understanding of the history of these vehicles. Older works of literature, such as those authored by Spielberger and Milsom, also summarise the history of the D II as presented in the BAOR report, but they should be used with caution when researching the rest of the Sd.Kfz.10 family, as they each contain errors and outdated information. Finally, a considerable number of photos of the D II that have not been published in printed books have surfaced on the internet, the majority of which have been published in this article.



Illustration of the Demag D II 1 half-track prototype with the rear-mounted engine and with the windshield up.
Illustration of the Demag D II 3 half-track prototype with the engine in the front.

Both illustrations by Alexe ‘Carpaticus’ Pavel, funded by our Patreon campaign.

Variant D II 1 D II 2 D II 3
Crew 1 + 3 1 + 3 1 + 5
Dimensions ? 3.4m (L) x 1.6m (W) x 1.7m (H) 4.4m (L) x 1.8m (W) x 1.7m (H)
Weight (laden) ? 2,560kg 3,400kg
Automotive Components 28 HP BMW 315 1.479 litre 6-cylinder petrol engine
ZF 4-speed transmission
28 HP BMW 315 1.479 litre 6-cylinder Petrol Engine
ZF 4-speed transmission
42 HP BMW 319 1.971 litre 6-cylinder petrol engine
ZF 4-speed transmission
Towing Capacity ? 600kg 600kg
Maximum Speed ? 50 km/hr ?
Range ? 250 km (on roads) ?
Gradient ? 24 degrees (without load)
12 degrees (with load)
?

Sources

Doyle, Hilary L., and Jentz, Thomas L., Panzer Tracts No.22-1 Leichter Zugkraftwagen 1 t (Sd.Kfz.10) Ausf.A und B and Variants: Development and Production from 1935 to 1945 (Maryland: Panzer Tracts, 2009).
Milsom, John, German Half-Tracked Vehicles of World War 2: Unarmoured Support Vehicles of the German Army 1933-45 (London: Arms and Armour Press, 1975).
Spielberger, Walter J., Die Halbkettenfahrzeuge des deutschen Heeres 1909-1945 (Stuttgart: Motorbuch Verlag, 1976). Translated into English as Halftrack Vehicles of the German Army 1909-1945 (Pennsylvania: Schiffer Publishing US, 2008).
Spielberger, Walter J., Die Motorisierung der deutschen Reichswehr 1920-1935 (Stuttgart: Motorbuch Verlag, 1979).Photograph of D II 2. Date of Access: 14 June 2018.
Photographs of the D II 3. Date of Access: 14 June 2018.


Categories
WW2 German prototypes

Tigerjäger Design B

Nazi Germany (1943)
Assault Gun – Design Only

The Jagdtiger (Hunting Tiger) is a highly recognizable vehicle consisting of a huge flat-sided casemate built on the hull of the Tiger II Heavy Tank. What is less well known is that the Jagdtiger as we know it (design started in early 1943), was not the vehicle originally requested and that, by tracking that design philosophy and evidence, it is possible to see a completely different Jagdtiger; one which was never built yet still offers a fuller picture of the evolution of German heavy armor in the Second World War.

Conception

In the spring of 1942, the Army General Staff was requesting a 12.8 cm gun mounted on a self-propelled chassis capable of supporting the infantry and of destroying unarmored as well as armored targets at distances up to 3,000 m. Armor and firepower were the priority, not speed and maneuverability.

By 2nd February 1943, this demand became an official request in the form of a letter sent from Wa Prüf 4 (the Army High Command design office for artillery) to Friedrich Krupp of Essen, setting out the requirement to mount a 12.8 cm Sturmkanone (Eng: Assault Gun abbreviated to ‘Stu.K’) on a modified Tiger H3. The ‘Tiger H3’ concerned was what we now know as the Tiger II, which was not named as such until March 1943 following the abandonment of the VK45.02(H), which was at the time known as Tiger II.

The requirements from Wa Prüf 4 for the modifications meant moving the engine forward on the chassis, with the gun being mounted in a casemate at the rear. This philosophy was felt to have the advantage of keeping the barrel overhang for the tank to a minimum and allowing for a better distribution of weight, although it was not without problems, as would soon become apparent.

The firm of Henschel und Sohn of Kassel would be responsible for the design of the hull modifications to fulfill this project and was contracted to produce designs. The gun desired was a 12.8 cm Stu.K, and the intention was to simply take the 12.8 cm Kw.K. L/55 gun unchanged, in its entirety, along with mounts, breech, brake, and recuperator from the Pz.Kpfw. Maus, although there was a strong emphasis placed by the High Command on the removal of the muzzle brake, as this allowed the use of Triebspiegel shells for heavy anti-armor work. The design, therefore, was not simply an assault gun, but also a tank-destroyer too, the difference between the two being blurred in this regard.

Further requirements set out in this letter were the use of as simple a design as possible with an elevation of -8 to +15 and 15 degrees of traverse. The sighting for the gun consisted of the Sfl.Z.F.5 and Rbl.F.36 telescopes to allow for both direct and also indirect fire.

Panzerjäger Panther design

By the start of 1943, the attempts to mount a 12.8 cm gun on a chassis were focused on using either the Panther or Tiger II as a basis. The Panther design to mount this 12.8 cm gun followed the design request closely. The engine, cooling, and ancillaries were moved to the front of the hull, behind the driver and radio operator, with the fighting compartment at the back.

Panzerjäger Panther mit 12.8 cm. Note: image has been cropped and cleaned. Source: Hoffschmidt and Tantum

The 12.8cm L/55 gun was mounted in the front of a well-sloped casemate with sloping sides, a flat roof, and a sloping rear, rather akin to the design of the back of the Ferdinand. Elevation limits for this gun were just +15 degrees to -6.5 degrees which did not meet the -8 degrees desired. Further, the rather small space of the casemate for the breech of this huge gun likely restricted the traverse to below the required 15 degrees each way.

The advantages of the design, such as the less complex and expensive Panther chassis compared to the Tiger II chassis, and the reduced length, just 8.5 m long from the muzzle to the rear, were offset by its deficiencies, such as the gun placement complicating maintenance of the engine and transmission. It is also possible that the armor which could be carried was not felt to be sufficient on the Panther chassis but, regardless of why the design was dropped, the attention was switched to the Tiger II chassis instead.

Enter the Tigerjäger

The Panzerjäger Panther design was dropped at some point, but Dr. Erwin Aders, the design lead at Henschel und Sohn, was working on two alternative designs for a Panzerjager based on the new Tiger II design. By March 1943, Aders was actively considering armor for the design up to 200 mm thick on the front and up to 100 mm on the sides, although this was subject to change in order to keep the weight to 70-tonnes (77.16 tons) or less. The goal was to provide a finished design by June 1943.

On 12th April 1943, Aders’ designs for Henschel were ready and the name being used at the time was Tigerjäger (Hunting Tiger). Designs plural, because Aders presented not one design but two: Tigerjäger Design A and Tigerjäger Design B.

Competing Designs

Design A had completely disregarded the requirement of the initial design brief to move the engine to the front of the hull. Instead, this design kept the engine at the back, with the transmission at the front as it was already arranged on the Tiger II. Despite this, the hull still had to be lengthened by 300 mm. Spielberger, Jentz, and Doyle (2007) describe the frontal armor of this design as being 150 mm at 40 degrees on the glacis and 200 mm thick on the 60-degree sloping part on the front of the casemate. However, the side armor had been reduced from the 100 mm desired in March to just 80 mm in order to keep the weight down. In other words, the frontal armor was now effectively double or more than the Tiger I but with the same side armor as the Tiger II.

Construction of a casemate with the armor desired and enough room for the breech of the huge 12.8 cm gun created a major problem and the height of Design A had to be reduced by 40 mm to allow it to fit inside the German rail gauge height limits for transportation. This had the effect of reducing gun depression from the -8 desired to -7 but, other than that, the design had met almost all of the requirements desired in the original letter from Wa Prüf 4 in February.

Design B, on the other hand, was significantly more problematic. In order to meet the requirements of Wa Prüf 4’s request to move the engine to the front, the hull roof had to be raised. Further, the cooling system of fans and radiators would not fit and would require a total redesign but even so, the engine was put in the middle of the hull. This, in turn, created additional problems with the transmission of power from the engine to the transmission at the front and to resolve that dilemma would mean designing new intermediate gearing. If that was not bad enough, Dr. Aders had not managed to design an effective system for exhaust from the engine and ventilation as the new arrangement had created so many difficulties for the design, and that was just the automotive problems.

Along with this total redesign of the Tiger II to accommodate this new automotive arrangement and the casemate at the back, the vehicle was too large for the rail gauge. Altering the design in order to meet this limitation would further reduce the movement of the gun which was already reduced by the height of the hull in front of the casemate. Assuming for a moment that the height could be amended in the same manner as Design A, reducing the -8 depression to just -7, then we can only surmise that the figure of -7 would be yet further reduced by this engine deck-height issue to -6 or less. Significant benefits of this gun mounting which should not be forgotten, however, were that it kept the center-of-gravity of the vehicle further back and meant there was very little overhang of the gun over the front of the hull.

One more problem to add to this litany of issues was maintenance. Not only would Design B require parts unique to it which were not compatible with the Tiger II, such as the gearing and cooling systems, but access to these parts was hard too. The 12.8 cm gun and mantlet would overhang the engine deck and, with limited traverse and elevation, there was no means to remove the engine or transmission without first removing the gun. This would also have to be done anyway for the Design A option but only for a change of the transmission and not for the engine. A short note here is that, at this time, the only engine being considered for the Tigerjäger was the same as that of the Tiger II, the Maybach HL 230 TRM producing 700 hp.

When Design A was amended with the casemate 200 mm further back due to a design change over the gun mounting, it resolved the centre-of-gravity issues and also reduced the gun overhang at the front. Design B, therefore, offered little in the way of advantages over Design A and a whole slew of major and unresolved problems. With an urgency to get this heavy 12.8 cm assault gun platform into service, there was only one logical choice and Design A, despite not being the engine-forward design requested, was selected instead. Design A went on to be the Jagdtiger and Design B was dropped.

The Duplicate

The first ‘Tigerjäger Design B’, as previously described, dates to the first half of April 1944 and the creative mind of Dr. Aders at Henschel und Sohn. Just to be confusing for historians, there is another Tigerjäger Design B. In fact, it is actually written as ‘Tiger-Jäger B’ and also emerges from Henschel just a month after the first Tigerjäger Design B. This means it is almost certainly from Dr. Aders as well, as he was the chief designer at Henschel.

Given the fact it was almost certainly proposed by the same designer responsible for Tigerjäger Design A and Tigerjäger Design B, from the same firm and only separated by a month, it would be easy to assume that there may be an error and that there was, in fact, only 1 Tigerjäger Design B. Here though there is a lucky break for the curious, as the plans for the May 1944 Tigerjäger Design B, unlike the April 1944 Tigerjäger Design B, actually survive.

Tiger-Jäger B with 12.8cm L/55. This is a different Tigerjäger Design dated 15th May 1943. Source: Hoffschmidt

Looking at the plans for the May Tigerjäger Design B and comparing it to the description known for the April design, it becomes very apparent that they are not the same vehicle which have been confused. The April vehicle was an engine-forward, rear casemate design with the 12.8cm gun over the engine with a small projection, whereas the May vehicle is the engine-rearward center-casemate design just like that known for Tigerjäger Design A from April, mounting the same gun but only over the front of the hull and projecting forwards.

The May Tigerjäger Design B initially looks like Design A, but there is one key visual difference that is easy to overlook; a cut-away portion on the top edge of the glacis. This cut-away reduced the point at which the gun would foul on the hull during depression.

The armor listed on the plan for the May Tigerjäger Design B also matches the armor described for the April Tigerjäger Design A, namely 200 mm on the front of the casemate, 150 mm on the glacis, and 80 mm on the sides. As these armor figures both pre- and post-date the April Tigerjäger Design B, it can be reasonably assumed even without the plans that the armor would be the same.

Resurrection: September 1943

Design B might have failed but the idea of sticking the 12.8 cm gun is a rear-casemate engine-forward design certainly had one last surprise. This time it was not from Henschel but from Krupp.

On 24th September 1943, Colonel Crohn (Wa Prüf 6) wrote to Krupp about improving the armament for the Tigerjäger, which was now the Henschel Design A type vehicle. There had been problems with the 12.8cm L/55 from Krupp which was, as yet, still unfinished. The gun suggested by Colonel Crohn was the 12.8cm L/70 version of the gun which used the same two-piece ammunition as the shorter gun but would deliver a higher muzzle velocity for armor-piercing rounds.

Krupp set to work and on 21st October replied that they had altered the design (the current Design-A type vehicle) to take the L/70 instead of the L/55. The gun could still fit in the same mounts as the L/55 gun but caused serious problems. The extremely long barrel now projected nearly 5 m beyond the front of the tank, bringing the center of gravity much further forwards, leaving a great strain on the front suspension.

The solution, in one way, was obvious – put the gun further back. In fact, mount the gun in a casemate at the back of the hull and, in doing so, move the engine forwards. This was then unsurprisingly exactly what Krupp suggested. At the same time, they outlined what effect the use of an L/70 would have on the primary design they suggested, and outlined this exact alternative, namely moving the engine forwards and the gun backward. This would reduce the overhang at the front to just 2 m or so and bring the center-of-gravity further back too. The drawbacks though, would be the same as before on the Design B and, on top of this, Krupp foresaw an increase in weight too on top of the weight of the heavier gun. Krupp said that it would consult with Henschel on the matter but, as Henschel had already considered this problem, it is no surprise that this idea died as quickly as it started.

By the end of October 1943 then it can be said that the rear-casemate engine-forward Tigerjäger was well and truly dead as an idea.

Clues

Because the designs were both rejected,k as both had so many faults and neither drawing has survived, it is perhaps no surprise that the descriptions provided, along with a knowledge of the development of the 12.8 cm Panzerjager and Tiger II programs, only allow for an approximation or surmised layout to be offered.

Looking at all of the other Panzerjägers following this engine-forward principle, such as the Panzerjäger IV mit 8.8 cm L/71, the Elefant/Ferdinand with the 8.8 cm L/71, and the Panzerjäger Panther with the 12.8 cm L/55, they all share the same core elements of sloping casemate sides, flat roof, and a rear which slopes both out from the floor to about the midpoint before sloping back to meet the casemate roof.

It is also worth considering that rear-mounted guns were actually installed on the Tiger II chassis, such as the 17 cm Selsfahrlafette 17/21, better known as the ‘Grille’ (Cricket). For that design, the engine was brought forward and the gun taken to the rear. A look at the engine position in the Grille, therefore, provides a view of what the front section of Design B might have looked like with the engine brought forwards. Why was it not a problem for the Grille when this layout was such a problem for the Tigerjäger? Simple: the Grille’s 17cm gun could be elevated far enough that access to the engine and transmission was relatively easy, as the gun did not need to be removed first.

Plan view of the 17cm Grille using the Tiger II chassis with the engine brought forwards. The vehicle is facing to the left and the front of the casemate for the gun on the Grille is outlined. This illustrates yet another problem with the engine-forward design – the isolation of the two crew at the front from the crew in the back. Source: Frohlich
Artist’s impression of the Tigerjäger Design B. Source: Author

Without seeing the original design, it is not possible to know for sure what Tigerjäger Design B looked like and the ‘invention’ of a tank, however reasonable it may look, is avoided by serious historians, which is why the artist’s impression shown here by the author is offered with the warning that it is exactly that, a rough impression of what it might have looked like based only on the little information available and from contemporary designs. Only if, and when, the original drawings are found can it be known for sure how close this impression is to reality.

Conclusion

The Tigerjäger Design B was literally a ‘paper panzer’ – it never left the drawing board. Designed by Henschel exactly as was actually demanded, it was simply surpassed by the alternative design (Design A), the design which went on to be the Jagdtiger. Using a rear casemate design with the engine forward would have allowed the use of the 12.8cm L/55 (April/May 1943) or even L/70 (September/October 1943) without the otherwise enormous overhang and without the excessive weight on the front suspension. Nonetheless, the design caused other problems relating to maintenance, the need for new component parts and really was not needed. There had been serious delays already in the Jagdtiger program at the time and 12.8cm L/55 production was behind schedule; switching to a longer gun would simply have slowed things down even more and the L/70 was simply not necessary to deal with its intended targets.

Krupp’s ideas for mounting the L/70 in the Design A never came about either and its ideas about moving the casemate to the rear were equally impractical given the problems of engine access. As it was, the Jagdtiger would follow a more conventional layout and the Design B of April 1943 was dropped. Together, the discussions over the Tigerjäger come together to provide a fuller picture of the small, but important steps in the evolutionary process for the Germans’ heavy Jagdtiger program.



Illustration of the Tigerjäger Design B produced by Mr. C. Ryan, funded by our Patreon Campaign

Tigerjäger Design B (April – March 1943)

Total weight, battle-ready est. 75 tonnes
Crew 6
Propulsion Maybach HL 230 TRM petrol producing 700hp
Armament 12.8cm Kw.K. L/55 plus hull mounted machine gun
Armor Up to 200 mm frontal, 80 mm sides and rear. 40-50 mm roof

Tigerjäger Design B (September-October 1943)

Total weight, battle-ready est. 70 – 75 tonnes
Crew 6
Propulsion Maybach HL 230 TRM petrol producing 700hp
Armament 12.8cm Kw.K. L/70 plus hull mounted machine gun
Armor Up to 200 mm frontal, 80 mm sides and rear. 40-50 mm roof

Sources

Spielberger, W., Doyle, H., Jentz, T. (2007). Heavy Jagdpanzer: Development, Production, Operations. Schiffer Military History, PA, USA
Hoffschmidt, E., Tantum, W. (1988). German Tank and Antitank. WE Inc., CT, USA


Categories
WW2 German prototypes

Pz.Kpfw. Panther With 8.8 cm Gun Design Proposals

 

Nazi Germany (1944-45)
Medium tank – Project only

By 1944, the fate of the Großdeutsches Reich (English: ´Greater German Reich´), more colloquially known as Nazi Germany, started becoming clearer and it was certainly not in the favor of the Germans. However, the German nation was not ready to surrender. As a result, the Panzerkampfwagen V Panther, one of the armored staples of the Wehrmacht at the time, continued to see development and upgrades until Germany’s eventual defeat in May of 1945.
While the 7.5cm Kw.K.42 L/70 main gun on the Pz.Kpfw. V Panther was a formidable tank gun capable of engaging any armored vehicle the Allies were able to field at the time, it was felt that the gun lacked enough future-proofing. In retrospect, these sentiments may not have been completely unjustified seeing as how vehicles developed by the Soviet Union near the end of the Second World War, like the T-54 and the IS-3, managed to be frontally resistant to the 8.8cm Kw.K.43 L/71 as mounted on the Panzerkampfwagen Tiger Ausf.B. Other vehicles, such as the United States’ Heavy Tank T32 and Heavy Tank T32E1, could also be theoretically frontally resistant to most of Germany’s anti-tank arsenal.

This IS-2 Mod.1944 was tested against the 8.8cm PaK.43 L/71 and 7.5cm Kw.K.42 L/70. The upper hull was impervious to the 7.5cm at any ranges while the 8.8cm could defeat it at 450 m, making it a great example as to the difference that an 8.8cm could have made in a real combat situation. Source: warspot.ru
During mid to late 1944, the firm of Daimler-Benz was in the midst of developing the Schmalturm (English: ‘narrow turret’), a replacement for the regular Rheinmetall-designed Panther turret. The Schmalturm was supposed to be used on the Panzerkampfwagen Panther Ausf.F. Considering that the Schmalturm was set to replace the original Rheinmetall turret and presumably Krupp thought that turret would be more accepting of a larger gun, Krupp designed an up-gunned version of the Schmalturm with a minimal amount of modifications. Krupp´s drawing Hln-130 (also referred to as Hln-B130), called ‘8.8cm L/71 I, Panther, schmal’ in at least one of the drawings, shows the Schmalturm mounting a modified version of the 8.8cm Kw.K.43 L/71 dating back to October 18, 1944.

Faded drawing of Hln-130 showing the internals of Krupp’s proposal from a top-down point of view with the turret facing left. (Source: Yuri Pasholok.)

Hln-130 modified to show major components of the turret. The red outline shows the armor structure, turret ring in orange, cupola in purple, bulbous turret extension in yellow, 8.8cm Kw.K.43 L/71 gun breech in brown, and 8,8cm round in green.
The gun was able to be accommodated by creating an armored bulbous extension at the front of the turret. The trunnions on the 8.8cm Kw.K.43 L/71´s gun carriage were moved 350 mm rearwards along the length of the gun, or the gun itself was moved 350mm forwards on the trunnions depending on how one wants to interpret it. The new gun mantlet was entirely different compared to the pot-shaped mantlet used on the regular Schmalturm. The installation of this new, larger gun compromised internal space and would mean that the loader would have a tough time loading rounds into the breech due to the limited amount of space between the gun breech and the rear of the turret. The round had to be loaded at an angle going upwards from the base of the turret, where there was enough room to squeeze in the round to the breech. One further modification was that the aperture for the main gun differed from the regular Schmalturm, although the apertures for the gunsight and machine gun were to remain identical.
Krupp´s Hln-E142 drawing, called ´Pz.Kpfw. “Panther” mit 8.8cm L/71 (Kw.K.43)´, dating back to November 17, 1944, shows the turret from drawing Hln-130 or the Schmalturm mounting the 8.8cm Kw.K.43 L/71 mounted onto a regular Panzerkampfwagen V Panther chassis. Here it is revealed that the gun has a depression angle of -8 and elevation angle of +15. The whole length of the vehicle with the turret and gun facing forward is 9,250 mm (9.25 m) with the length from the very front of the chassis to the end of the gun being 2,650 mm (2.65 m) and the vehicle (excluding gun) being 6,600 mm (6.60 m) long. On December 4, 1944, Wa Prüf 6, the department of the Waffenamt in charge of the development of armored and motorized vehicles, awarded Krupp a development contract.

Drawing Hln-E142 showing Krupp’s proposal for mounting an 8.8cm Kw.K.43 L/71 onto a Pz.Kpfw. V Panther chassis. Source: Yuri Pasholok
Krupp was curious about Wa Prüf 6’s opinions on some of the aspects of the proposal and whether further development was worthy of advancing forward. Krupp asked Wa Prüf 6 these three following questions, which are taken verbatim from Germany’s Panther Tank: The Quest for Combat Supremacy.

  • Is there sufficient space for the loader?
  • Is the shape of the armored cover in the turret front plate acceptable?
  • Is relocating the center of balance about 200 mm forward plus a weight increase of 900 kg bearable?

For the first question, Krupp proposed mounting a wooden model of the 8.8cm Kw.K.43 onto a “Panther turret” in order to test the loading of the main gun. For the third question, Krupp proposed a test turret with the load being off-center. Wa Prüf 6’s exact responses are not known.
For the sake of brevity, Schmalturm mounting the 8.8cm Kw.K.43 L/71 on a Panzerkampfwagen V Panther will be referred to as ‘Panther-Schmalturm-8.8cm’ although it is important to note that this is not an official name and used here solely for clarity.

Renditions of Krupp’s Panther-Schmalturm-8.8cm proposal. Source: Doyle and Jentz

Daimler-Benz Joins In

A meeting by the Entwicklungskommission Panzer (English: ‘Tank Development Commission’) was held on January 23, 1945, in which Colonel Holzäuer from Wa Prüf 6 reported that development of the Panther-Schmalturm-8.8cm project was to be completed by Daimler-Benz. In addition, a wooden model is said to have been completed. Earlier, on December 12, 1944, Daimler-Benz had displayed a wooden model of the vehicle, but it is not known if it was the same wooden model Colonel Holzäuer reported or an unknown previous iteration.
The turret ring of the Daimler-Benz Panther-Schmalturm-8.8cm was to be enlarged by 100 mm, making it 1,750 mm compared to the turret ring on the regular Rheinmetall-designed turret on the Panzerkampfwagen V Panther (Ausf.D to G), which was 1,650 mm. In doing so it gained a single tonne of weight. It also carried 56 rounds for the main gun.
On February 20, 1945, Krupp and Daimler-Benz representatives, Wa Prüf 6, and Wa Prüf 4 (a sister department to Wa Prüf 6 in charge of the development of artillery) held a meeting comparing both Daimler-Benz and Krupp’s Panther-Schmalturm-8.8cm designs. One large difference was the gun itself. Daimler-Benz used a ‘8.8cm Kw.K.’ with the recoil cylinders installed underneath the gun and the turret ring widened by 100 mm, while Krupp opted to use, for the most part, a regular 8.8cm Kw.K.43 L/71 with repositioned trunnions in a mostly unchanged Schmalturm turret as mentioned earlier. Wa Prüf 6 recognized that Krupp’s design was an expedient one meant to save time, however, their representatives did not much appreciate the idea.
In the end, it was proposed that Daimler-Benz and Krupp would work together on a project involving the 8.8cm Kw.K.43 L/71 with relocated trunnions and a larger turret ring with Daimler-Benz tackling the turret and Krupp the gun, unsurprisingly. This would have lead to the creation of a more complex project, but also combine the best elements of both designs and create additional space inside the turret.
On February 27, 1945, it was decided by Wa Prüf 6 that Daimler-Benz would continue development of the Panther-Schmalturm-8.8cm and was slated to produce a soft steel prototype of the turret to the specifications listed. Some of the specifications listed below reflect Krupp’s Panther-Schmalturm-8.8cm design which might indicate their involvement.

  • Needed to depress -8 degrees and elevate 15 degrees, which Krupp’s design was able to achieve.
  • The turret ring diameter was to be enlarged to 1,750 mm which was designed to give the loader more room to do his duties. Daimler-Benz’s previous design had already accomplished this.
  • The vehicle had to use only the 8.8cm Kw.K.43 L/71 as its main gun. The bore evacuation cylinder was to be placed in the middle of the recoil cylinders above the gun.
  • The trunnions were relocated and the muzzle brake was removed similar to Krupp’s Panther-Schmalturm-8.8cm.
  • Interestingly, the trunnions were to be located on the “forward edge” of the turret front plate, implying that it lacked any turret front extension like Krupp’s design.
  • The turret front was to have a “smooth armor plate” with the apertures being as small as possible but including an aperture for the main gun, presumably with the coaxial machine gun included. It is not clear if the turret was to be equipped with a telescopic gunsight or a coaxial machine gun
  • Mounting the S.Z.F.2 or S.Z.F.3 stabilized gunsight was to be considered.
  • The turret traverse gear and the cupola were to stay the same as on the regular Schmalturm.
  • The design was to use either a 1.32 m or 1.65 m stereoscopic rangefinder. It should be noted that the regular Schmalturm could already mount a 1.32 m stereoscopic rangefinder.
  • The turret was to feature ready racks which would make ammunition easily accessible.
  • Emphasis was placed on a low turret height.
  • Lastly, the rear turret plate was to be sloped instead of “upright” as it was on the first wooden model of the Daimler-Benz Panther-Schmalturm-8.8cm. The wooden model might be the one showed off on December 12, 1944, but this is just speculation.

Krupp’s Return and Wa Prüf 6’s Variant

Krupp appears to have returned to the project under the request of Colonel Crohn from Wa Prüf 6 on March 8, 1945. They were to design an “armor shell” of the Pz.Kpfw. Panther Ausf.F turret (otherwise known as a Schmalturm) mounting the 8.8cm Kw.K.43 L/71 by March 12, 1945. Speculatively, considering that they were given four days to design, it might be the case that they simply took their previous design, such as like Hln-130 or a similar iteration around the same time, and adapted it to the existing Schmalturm design of the time.
On March 14, 1945, during a discussion of further developing the Panzerkampfwagen V Panther in the Generalinspekteur der Panzertruppen, the Waffenamt is said to have done an excellent job designing the ‘8.8cm Kw.K. L/71’ onto a Panzerkampfwagen V Panther, with Wa Prüf 6 being thanked specifically. If the Waffenamt’s ‘8.8cm Panther’ was to be put into production, existing Panthers that received major overhauls would also be subject to mounting a turret with the 8.8cm. A ‘Versuchs-Panther’ or a prototype of the 8.8cm Panther was to be built out of soft steel and completed by early June. Mass production was to begin in the last quarter of 1945 if the “necessary support” was given.
This significantly improved vehicle with the new turret and increased firepower would weigh just one tonne more than the “current Panther”. Armor was to protect the rangefinder and it featured a stabilized gun sight “about the same as the Panther-Schmalturm”. Fifteen rounds were to be stored and be accessible in the turret and fifty to fifty-four more rounds were to be stored in the hull, meaning a total of 65 to 69 rounds could be carried.
Wa Prüf 6 was requested by the Generalinspekteur der Panzertruppen on March 14, 1945, to build a Versuchs-Panther mounting an 8.8cm Kw.K. L/71 based off the wooden model Daimler-Benz had shown off on December 12, 1944. The turret was to be made out of soft steel and the superstructure of the hull was to be modified in an unspecified way. Wa Prüf 6 was to complete the Versuchs-Panther quickly and display the vehicle on time.
Albert Speer, who was the Reich Minister of the Reichsministerium für Bewaffnung und Munition (English: ‘Reich Ministry of Armaments and Munitions’), requested on March 23, 1945, a display of a Panther armed with an 8.8cm Kw.K. gun, along with other weaponry, to be viewed by Adolf Hitler some time in mid-April. Hitler, however, was never able to see the vehicle as it was never built.
Daimler-Benz representatives were interrogated by the Allies after the Second World War had ended. They claimed that they had made plans to mount the 8.8cm Kw.K.43 L/71 onto a Schmalturm equipped with a stabilized gun sight with the project still being early in development. A wooden mockup of the project apparently existed up to June of 1945, three months after the German defeat, but after that it was lost to time.

Conclusion

The Panther-Schmalturm-8.8cm isn’t one homogenous project as it is sometimes depicted. It is a series of unrelated and related projects from various different firms and organizations. In the end, arming the Panzerkampfwagen V Panther with an 8.8cm L/71 in a Schmalturm became little more than a fantasy. The war was nearing its end when actual progress was made and such a turret would have made no difference to the outcome of the war. Krupp’s proposal though would have been the most feasible when compared to the design from Wa Prüf 6 and Daimler-Benz’, since it was simply a regular Schmalturm with the 8.8cm Kw.K.43 L/71 stuffed inside. The Panzerkampfwagen Panther Ausf.F was already placed into production and at least two mostly finished Schmalturms were made by the end of the war, one of which was captured and analyzed by the United States and the other captured and analyzed by the United Kingdom before ending up as a range target. However, there would have been issues with this design. Along with the bigger gun, the design was, in general, worse ergonomically for the crew and the cramped interior would have hampered the crews’ ability to carry out their tasks. There is no real surprise as to why Wa Prüf 6 was not fond of this design.
On the other hand, it is rather difficult to judge the Daimler-Benz or Wa Prüf 6 designs as very little is actually known. It appears, though, that the Daimler-Benz design would have required significant changes to an already existing design (Schmalturm) which would cause even further delays. In the case of Wa Prüf 6’s design, not only was the design of the turret changed, but existing Panthers would have to have their turret rings widened by 100 mm which would cause even more significant delays.
Despite the technical challenges of fitting an 8.8cm L/71 gun into a space smaller than that which had previously accommodated a 7.5cm gun, all designs managed to come up with workable solutions. Undoubtedly, had the final design for the compromise Schmalturm come to fruition, it would have made the new Panther a more powerful vehicle on the battlefield with a smaller silhouette, smaller profile, more firepower and improved protection, but at the expense of the crew ergonomics in the turret and their ability to carry out their tasks.

Sources

Jentz, T.L. 1995. Germany’s Panther Tank: The Quest for Combat Supremacy. 1st ed. Atglen, Pennsylvania: Schiffer Publishing Ltd.
Jentz, T.L. & Doyle, H.L. 2001. Panther Tracts No. 20-1: Paper Panzers.1st ed. Boyds, Maryland: Panzer Tracts

Specifications for Krupp’s 8.8cm Schmalturm turret

Crew 3 (commander, loader, and gunner)
Armament 8.8cm Kw.K.43 L/71
-8/+15 gun elevation
Armor Armor: Presumably identical to Schmalturm with the exception of the mantlet and bulbous turret extension
Turret front: 120 mm (20 degrees)
Turret sides and rear: 60 mm (25 degrees)
Roof: 40 mm (horizontally flat)
For information about abbreviations check the Lexical Index


Krupp’s proposal for mounting an 8.8cm Kw.K.43 L/71 onto a Pz.Kpfw. V Panther chassis according to drawing Hln-E142. Illustration by Andrei “Octo10” Kirushkin. Funded by our Patreon campaign.