Cold War French Prototypes

Batignolles-Châtillon 12t

France (1947-1951)
Light Tank – 1 Prototype Built

France was, in the 1930s, a major tank-producing nation in Europe, second only to the Soviet Union and Germany in output. This productive industry, which, while designing tanks that often followed archaic requirements, used modern technology, saw its abilities to continue evolving and producing new vehicles mutilated by the German invasion of France and the Low Countries in the spring of 1940. As part of the Compiègne armistice imposed on France, production and design of new tanks was strictly forbidden, and only a few designs, some covert and some designed for potential use by Axis nations, would prop up in the following years – most based on pre-existing technology and hulls which could not match newer vehicles developed by other countries.

France was liberated in 1944, with the new government, at this point under De Gaulle, adamant in its goal to recover French independence and self-sufficiency. Getting the military industry back up was one of several aspects of this policy. It was in this context that, in 1947, the French army would establish requirements for an airborne, 12-tonne light tank armed with a high-velocity 75 mm anti-tank gun with anti-armor capacities; a fairly ambitious prospect. Three manufacturers were approached to design such a vehicle, or at least its chassis: the state workshop of AMX, the old Mediterranean shipyard of FCM, and lastly, the locomotive-turned-tanks manufacturer Batignolle-Châtillons.

A Resurgent Tank Industry

Before the outbreak of the Second World War, France was one of the largest tank manufacturers on the European continent and in the world, second only to two nations which far outmatched France’s population and industrial potential, Germany and the Soviet Union. The defeat of France in 1940, of which inadequate tank designs and use is one of many culprits, led to the country being occupied all the way to the summer of 1944. Outside of a few covert projects undertaken by a secretive organisation of the Vichy regime, the CDM (Camouflage du Matériel/Equipment Camouflage), new developments were practically stopped. The few new designs considered, such as the SARL 42, largely took the basis of elements existing or already being studied in 1940. France was wholefully unable to keep up with the technological advancements that countries with intact or at least functioning tank industries were developing and fielding during the war.

The first ‘new’ French armored fighting vehicle to enter production following the liberation of France, the Panhard 178B, was, in practice, the combination of a hull and gun already in existence in 1940 with a new turret. Source: char-français

Following France’s liberation by the Western Allies and FFI (Forces Françaises de l’Intérieur – English: French Forces of the Interior) uprisings in the summer of 1944, the new French leadership, still under Charles de Gaulle, was very keen on ensuring France’s independence to the best of their capacities. This included resuming work on indigenous armaments projects as swiftly as possible. The first of the post-war designs would be worked on as early as 1944, largely based on pre-war designs and concepts or salvaged German equipment, adapted as best as possible to still be suitable for use in a postwar context. The two best examples of these first attempts at kicking a tank industry back on its feet, the ARL 44 and Panhard 178B, were neither revolutionary nor even truly modern vehicles, yet one could hardly say they were not successful in their roles. The ARL heavy tank was the first true French tank manufactured post-war, helping the industrials get back into shape, while the Panhard 178B not only did the same for France’s most important wheeled armored fighting vehicles manufacturer, Panhard, but also provided an indigenous vehicle to supplement the plethora of American and British types used to maintain a French colonial empire now at the brink of collapse, particularly in Indochina.

Work on these vehicles was well underway by the summer of 1946. The Panhard 178B had entered mass-production, while the ARL 44 at least had a functional vehicle completed, though it would eventually be a far fetch from the production standard. Following this, more ambitious and truly new vehicles could begin to be considered.

It is in this context that, in September 1946, the French EMA (Etat Major des Armées – English: Army General Staff) requested DEFA (Direction des études et fabrications d’armement – English: Armament Studies and Manufacturing Direction), the organism in charge of managing the production of French military equipment, to oversee the creation of an air-transportable reconnaissance vehicle which would weigh 12 tonnes at most. Within the French Army’s technical services, there was a preference for a light tank which would feature heavy armament for its weight, making it able to engage enemy armor, rather than be a more passive, lightly-armed reconnaissance vehicle. Mobility was also an important factor to compensate for the necessarily weak armor such a vehicle would possess. As such, one could describe the vehicle which was envisioned as the combination of a reconnaissance vehicle, a light tank and a tank destroyer. Furthermore, as early as January 1947, additional variants, in the shape of an anti-aircraft vehicle and a self-propelled artillery piece, which were to share a common chassis with the light tank, were being considered.

At this point, DEFA offered the STA (Service Technique des Armées – English: Technical Service of the Armies) the outline of three concepts. All would share an oscillating turret, a concept previously given only minimal attention, but which was viewed as potentially a good option to save weight. The concepts varied in the muzzle velocity of their 75 mm main guns, the goals being 600, 878, and 920 m/s. STA expressed interest in an oscillating turret fitted with the higher muzzle velocity main gun, a concept it accepted on 10th February 1947. By late February, the concept had been passed on to EMA, which set requirements for a 12 tonnes vehicle with a 75 mm gun that could reach at least 850 m/s, and optimally 1,100 m/s. At least 40 rounds were to be stowed within the vehicle. Fuel capacity was to be at least 300 l.

After these few months of back and forth and development of the concept by French Army structures, the requirements were eventually passed on to three manufacturers on 24th April 1947. These were the Atelier Mécaniques d’issy-Les-Moulineaux (AMX, English: Issy-Les-Moulineaux Mechanical Workshop), the Compagnie générale de Construction de locomotives Batignolles-Châtillon (English: Batignolles-Châtillon general locomotives Construction Company) and the Forges et Chantiers de la Méditerranée (English: Forges and Shipyards of the Mediterranean). All three had designed armored vehicles pre-war, though Batignolles-Châtillon did not have any production vehicles to its name. AMX had designed the R40, an evolution of the R35, and taken part in manufacturing the B1 Bis, while FCM had also had its own B1 Bis manufacturing chain as well as its own FCM 36 and FCM 2C designs.

The manufacturers were only requested to design the hull, as well as eventually the casemate for the self-propelled artillery version. The turrets for the light tank as well as anti-aircraft vehicles were to be procured from separate manufacturers.

A French Tank on a German-Style Suspension

The first known plans of the Batignolles-Châtillon 12t are dated from 31st October 1947. These show a light tank with a more centrally-mounted turret, rather than the rear-mounted turret that was present on both the FCM 12t and the AMX-12t.

A side profile view of the interleaved-suspension 12t proposal. This variant differed very significantly from all other proposals of the program, not only because of its interleaved road wheels, but also because of its use of a centrally-mounted turret and rear engine. Source: char-français
A top view of the 1947 design. With a driver to the front left and an engine to the rear, this was arguably the closest to classic tank architecture out of all the 12t proposals, but it also looked significantly larger than the other vehicles. Source: char-français
An approximately 1.80 m tall crewman standing aside the interleaved version of the 12t. In height at least, the vehicle was fairly low. Source: char-français.

The vehicle had a quite long hull for a light tank, with 5.050 m from the front to the rear of the track run. The height of the hull was of 1.240 m, and the width of the hull itself was 1.630 m, to which each 385 mm-wide set of track should be added, making the vehicle 2.4 m wide in total.

The vehicle’s suspension appears to have used, in this shape, a front-mounted sprocket and a rear-mounted idler. The most peculiar aspect of the suspension, though, would likely have been the road wheels. This early design used a set of seven interleaving road wheels on each side, a suspension-type typically present in late-war German designs, from which the French took heavy inspiration. The four outward wheels, each separated by a middle one, were doubled with another wheel on the inner side of the vehicle, while the middle wheels were single, but noticeably thicker. There was 2.8 m between the center of the first and last road wheel. The center of the first roadwheel was 1.140 m from the front of the track run, and the center of the last roadwheel 1.110 m from the rear of the track run.

Three unfortunately very blurry views of the schematics of the interleaved Batignolles-Châtillon 12T with the SAMM anti-aircraft turret. This turret was integrated into the design work from the very start. Source: Châtellerault archives
Set of plans of the artillery version of the interleaved road wheels Batignolles-Châtillon 12t. Source: Châtellerault archives, provided by Colasix

This 1947 set of plans show both the oscillating 75 mm-armed turret, still retaining the shorter gun that likely would have been the one with a 850 m/s velocity, and the anti-aircraft turret armed with a set of four MG 151/20 20 mm autocannons. The schematics of the 75 mm-armed vehicle, in particular, are very detailed when it comes to the internal arrangement of the hull. There were also schematics for an artillery version, which retained the centrally mounted armament; this vehicle used a casemate, with a small turret, likely some sort of commander’s cupola, armed with a 20mm autocannon.

The driver of the vehicle would have been seated at the front left, with seemingly the gearbox to his right and the transmission to his front. The combat compartment was to his immediate rear, with the commander sitting to the left of the gun and the gunner to its right. Hull ammunition stowage would be present immediately in front of them, at the front of the combat compartment and turret, where 26 rounds would be located. A further 8 rounds were present at the front left of the turret basket, and seemingly 4 rounds to the rear of the turret, in front of the engine compartment, giving a total of 38 rounds of ammunition stowage in addition to the 12 rounds already present in the two revolver-type magazines of the turret.

This detailed planview of the interleaved 12t’s arrangement shows, in great detail, the interior of the vehicle and features such as the ammunition stowage, but also the interleaving of the road wheels, doubled outward wheels and double-thickness inward wheels. Source: char-français
A profile cutaway view of the same proposal showing the driver with the head out of his hatch, as expected when driving outside of a combat zone. Source: char-français
This cutaway view of the interleaved 12t, looking towards the rear, shows not only the engine block in great detail, but also the interleaved roadwheel and how the central roadwheel is two times thicker than the outward ones. Source: char-français
This cutaway view of the front of the vehicle, looking towards the front, shows the position of the driver and transmission. Source: char-français

Though this version of the Batignolles-Châtillon 12t project is the first to be known, and appears in a quite detailed set of plans, the vehicle which would move further and reach prototype stage was vastly different from this one. It appears that the interleaved road wheels configuration was dropped early on and that the vehicle was deeply redesigned, with the overall dimensions of the hulls and tracks, for example, being changed as well. This was likely in an effort to reduce weight, seeing as the Batignolles-Châtillon project appeared, at this time, to have a larger volume than the FCM and AMX projects, in addition to interleaving road wheels which would typically add quite a lot of additional weight. Whether or not the vehicle would be able to remain below 12 tonnes was quite questionable.

Continuing Evolutions toward a Prototype

The set of projects from all three companies was approved by the STA on 24th May 1948 and cleared to continue. It appears that mock-ups were constructed by all manufacturers in the following months. However, the Batignolles-Châtillon project appears to have, around this point, started to accumulate delays. A formal order for a prototype appears to only have been passed on 14th February 1949, as order 18.211 – the same month the FCM prototype was completed. By December 1949, the FCM and AMX prototypes were compared to each other for a pre-production order of five vehicles. The AMX won and was picked for a pre-production run of five vehicles – basically setting it on the road to becoming the adopted vehicle. The Batignolles-Châtillon project did not take part in this comparison as a prototype was not yet completed.

Batignolles-Châtillon would only formally present the 12t vehicle in its facilities of Nantes on 13th June 1950. This was a very late date, and while AMX’s project would only formally be adopted in early 1951, it was clear at this point that it was picked in all but name – the Batignolles-Châtillon arrived too late to realistically have a chance to be picked. Trials were nonetheless run with the vehicle.



The design of the Batignolles-Châtillon 12t light tank in its final form is known mostly thanks to a set of plans dated from June of 1950. It appears that general ideas of the tank’s design had existed since about two years – we already know of schematics of a Batignolles-Châtillon 12t artillery vehicle dated from March 1948, which featured a similar suspension.

The March 1948 artillery Bat-Chat 12t schematics. This design already features the large individual road wheels and rear casemate/turret of the later design. Source: Châtellerault archives, provided by Colasix
June 1950 side profile of the Batignolles-Châtillon 12t light tank. The vehicle’s arrangement has little to nothing in common with the previous interleaved design. Source: Châtellerault archives

As the two other proposals born out of the same program, the Batignolles-Châtillon vehicle had opted for a rear-mounted turret, an entire change of configuration in comparison to the earlier interleaving road wheels design. The hull had a length of 4.38 m, and a height of 1.280 m at the top of the driver’s position. With the gun, the length would reach a higher 6.472 m, and the height 2.170 m.

The 12t’s hull had been designed to be as thin and compact as possible, with the track width being, in comparison, designed to be fairly large. The idea was that the hull would be as thin as the turret ring diameter, powertrain and driver’s post would realistically fit in, and these mechanical organs would be designed to be as compact as possible. In practice, the turret even had some moderate extrusions, as it would otherwise have had overhang from the side of the hull. The Batignolles-Châtillon’s vehicle hull was 1.46 m wide, with 100 mm separating this hull from the 370 mm-wide pair of tracks. Overall, the vehicle would have a width of 2.4 m, at this point identical to the earlier design. Ground clearance was 31.5 cm.

A front view of the vehicle from the same set of plans; the overhang of the turret ring is noticeable. Source: char-français
A plan view from the same set of plans. Source: Châtellerault archives

The hull was made of laminated steel plates assembled together by welding. The frontal protection of the hull was to be equivalent to 40 mm at a flat angle. In practice, this translated into the upper front plates being 25 mm thick angled at 15° and 27° degrees from the vertical. The lower front plate was 25 mm thick as well, angled 75° from the vertical. The front bottom was 15 mm thick, angled at 20°, while the rest of the vehicle appeared to have had a 10 mm-thick bottom. All three rear plates were 19 mm-thick, angled at 25°, 50° and 80° respectively. The roof was 10 mm thick, and the sides 20 mm. These values are taken from the trials report from 1951. The 1950 schematics are different in this regard, with the front reported to be 31 mm at its thickest point.

The armor layout of the 12t, from the October of 1951 trials report. It appears that, in June 1950, it was still planned to have a 31 mm thick frontal hull, though other aspects of the hull armor appear to have been identical between both documents. Source: Châtellerault archives

The driver of the Batignolles-Châtillon 12t was installed to the front left of the vehicle. He sat on a seat with two positions: an upper position would have the driver’s head stick out from the driver’s post, when driving outside of combat. In combat, the seat would be lowered. The driver would then observe the outside from a periscope. To his front, the commands at his disposal would be, from left to right, a direction lever for the left track, a handbrake, hand-controlled clutch, followed by foot pedals in the same order as in a civilian car: the brakes, the clutch pedal and the accelerator. The gear-selecting lever, direction lever for the right track, and a reverser lever for the transmission were located towards the driver’s front right. The gear-selective lever was preselective, as would be found in a typical car, with the driving elements of the vehicle had been designed to be as similar as a classic road vehicle. The hand-clutch command would only be used when starting up the vehicle, with the foot clutch pedal taking its place when the vehicle was running. The instrument panel would be located just right of the driver’s head. The oil circuit for the gearbox was installed over the foot pedals, with the oil filter to their right, behind the gear selector from the driver’s point of view. Brakes, gear and direction were all hydraulic Lockheed controls.

A top view of the driver’s post on the prototype, looking towards the right. The driver’s seat, gear selector, direction lever, and inversor toggle can all be seen. Source: Châtellerault archives
The 12t driver post’s dashboard, to the right of the lever. The gear selector on the bottom left can be seen. Source: Châtellerault archives
A photo of the driver’s post taken from the rear towards the front, showing the handbrake, clutch, and pedals. Source: Châtellerault archives
A view of the same driver’s post from slightly higher. The various pedals, and above them the gearbox oil circuits, with the oil filter to the right can be seen. Source: Châtellerault archives

Ammunition stowage within the hull at this point would have been of 22 rounds, a considerable reduction in comparison to the previous model.

Power train

The power train of the vehicle was located to the right of the driver, separated by a bulkhead. It was put together in a block which was designed so that the armor plating protecting it could easily be disassembled, in order to hasten maintenance or replacement work. This engine block sat on four mounts designed to prevent vibrations.

A view of the ventilation within the Batignolles-Châtillon 12t’s engine block. Source: Châtellerault archives

The vehicle appears to have been planned and tested with different engines. The first engine used in the Batignolles-Châtillon 12t was a Mathis 18 GZ 00 petrol aviation engine. This was a 4-stroke, 7-cylinders arranged in a ‘V’ , 6,827 litre engine. The vehicle later received a Mathis Type 8 GZ, which was an 8-cylinder engine. In order to reduce weight, it was decided that the vehicle would use air cooling. Air would enter from grills at the front of the engine block, go through two oil radiators (one for the engine and one for the gearbox), the cylinders, and be exhausted by a fan through another grill. The first engine and clutch mechanism had a weight of 365 kg together, including 20 l of oil. Later, the 8-cylinder engine had a weight of 327 kg, but it is unclear whether that was just the engine itself or also included the clutch mechanism and oil.

A front view of the Batignolles-Châtillon 12t prototype, showing the large air entry for the engine block. Source: Châtellerault archives

Clutch was assured by a singular disc. The Batignolles-Châtillon 12t used a gearbox with six gears. The first gear would multiply engine rotations by 22.5; the second by 6.23, third by 3.79, fourth by 2.38, fifth by 1.53, with the sixth rotating at the same rate as the engine. Direction was assured by a triple differential going through the gearbox. The gearbox was also relatively light, with merely 300 kg, including oiling systems.

The vehicle’s fuel tanks had a capacity of 300 litres and were located towards the rear of the vehicle, behind the turret ring.

A rear view of the Batignolles-Châtillon 12t prototype. The exhaust can be seen to the right; the port on the lower left is likely to fill the rear fuel tank. Source: Châtellerault archives

In general, the powertrain of the Batignolles-Châtillon 12t was remarkable in the compactness and lightweight it offered. When breaking down how the volume was shared inside the vehicle, the engine block, including the transmission, comprised 30% of the internal space; the driver’s position comprised 20%, the fuel tanks 10%, and the combat compartment behind and around the turret ring the remaining 40%.


This finalized version of the 12t had completely changed the whole suspension and mechanical arrangement of the vehicle, which no longer had anything in common with the previous interleaving road wheels.

A profile view of the Batignolles-Châtillon 12t prototype. The vehicle features two fairly large return rollers and two large shock absorbers. Source: Châtellerault archives
A close-up on two roadwheels of the Batignolles-Châtillon 12t prototype. Source: Châtellerault archives

The vehicle had now moved to using a torsion bar suspension with four large road wheels, with a diameter of 600 mm. Two large pneumatic shock absorbers were present on each side of the suspension, one at the front and one at the rear, each linked to two road wheels and guaranteeing a very smooth ride. These road wheels were not evenly spaced; the front one’s center was 830 mm from the second’s, which was 750 mm from the third’s, itself 690 mm from the fourth’s. The vehicle featured a large raised front sprocket, its center 778 mm from the first roadwheel’s, and a much smaller rear idler, its center 670 mm from the last roadwheel’s. Overall, the length between the centers of the first and last roadwheel was of 2,270 mm.

A photo of the 12t’s two-part track link. Source: Châtellerault Archives
The same track link and the track pin. Source: Châtellerault archives

The vehicle’s tracks were 370 mm wide with a 135 mm pitch. The ground pressure they would apply was 0.685 kg/cm² on soft soil, and 10.2 kg/cm² on hard soil.


The Batignolles-Châtillon 12t hull was designed to interchangeably mount two different turrets.

The first was the Fives-Lilles FL 4. This was an oscillating turret, the first known French post-war development in the field. It had been designed to mount a high-velocity 75 mm anti-tank gun. On the FCM 12t, it first appeared with a ‘short gun’ that was likely the projected weapon firing at 850 m/s, but the weapon that appears to have been durably retained would instead be the ‘1,000 m/s’ 75 mm gun, which would eventually be standardized as the 75 mm SA 50. The FL 4 oscillating turret allowed for an elevation of 13° and a depression of -6°.

This 75 mm SA 50 featured two armor-piercing shells. Both weighed 21 kg, with the projectile being 6.4 kg, and had a muzzle velocity of 1,000 m/s. The first, the POT modèle 1951/POT-51A (Perforant Ogive Traceur – English: Armor-Piercing Capped Tracer/ APC-T), would penetrate 110 mm at 90° and 60 mm at 30°, at a range of a kilometer. The second, PCOT modèle 1951/PCOT-51P (Perforant Coiffé Ogive Traceur – English: Armor-Piercing Capped Ballistic Cap Tracer / APCBC-T), would penetrate 170 mm at 90° and 40 mm at 30° at the same range of a kilometer. Lastly, a high-explosive shell existed, which had the same velocity but was slightly lighter (20.6 kg), with a projectile weight of 6.2 kg and an unknown explosive charge.

An AMX pre-production vehicle with the longer-barrelled 1,000 m/s 75 mm gun. The FL 4 turret which would have been mounted on the FCM 12t would have been closer to this one, rather than the one present in the September 1948 schematics. Source: flickr

The FL 4 was a two-man turret, with the commander to the left of the gun and the gunner to the right. The reason for this reduced crew was that the turret used a bustle autoloader system, with two 6-round revolver magazines located in the rear bustle of the turret. This solution took less space than a manual loader and, as such, helped lighten the vehicle, which was necessary for the air-transportability requirement. A total of 40 75 mm rounds would be stowed within the vehicle. The turret had a coaxial MAC 31 7.5 mm machine gun, with 1,050 rounds of ammunition stored. Frontal protection for the turret would be equivalent to 40 mm, while the sides and presumably rear were 16 mm thick and the roof 10 mm.

Observation devices included seven periscopes in the observation cupola for the commander, while the gunner could use an observation and targeting periscope as well as a gun sight. The turret featured an American SCR-508 radio, which would be shared by all versions of the vehicle. With the FL 4 turret, the vehicle was to be 2.170 m high.

The other turret which was to be featured in the Batignolles-Châtillon 12t was the SAMM S232 anti-aircraft turret. It was designed by the Société d’Application des Machines Motrices (English: Motor Machines Application Society) and was designed to be mounted on each of the three 12t light tanks projects. The first prototype was completed in May 1949.

A close-up of a SAMM S232 turret, this particular example mounted on an AMX-13 pre-production hull. Source: Les véhicules blindés Français 1944-1977

This turret’s armament consisted of four MG 151/20 20 mm autocannons of German origin. It was the standard 20 mm autocannon for Luftwaffe aircraft for most of the war. It fired 20×82 mm cartridges at a rate of up to 750 rounds per minute, with a muzzle velocity of up to 785 m/s. MG 151s, both in the 15 and 20 mm versions, were fairly widely used in post-war France, including in armored vehicles designs.

The S232 turret was 1.020 m high. As it was designed for anti-aircraft use, it had a high maximum elevation of 80°, with a more moderate depression of -5°. The turret used cast construction and was fully enclosed. The front had the same 40 mm of effective thickness as the FL 4, as did the sides at 16 mm. Likely in order to improve resistance to strafing, the roof armor was quite significantly thicker at 30 mm.

Weight Distribution and Expected Performances

The distribution of the weight in the 12t was to consist in:

2,180 kg of hull armor
3,630 kg from the suspension and wheels
365 kg from the engine, clutch, liaison between these, and 20 litre oil tank
300 kg for the gearbox and transmission including a 20 litre oil tank
70 kg for the radiator
55 kg for the controls
240 kg for the batteries
380 kg for miscellaneous elements such as the separations between the compartments, electric group and wiring, stowage, etc.
4,200 kg for the turret, including the two crewmen and 18 rounds of ammunition
80 kg from the driver
260 kg of fuel
300 kg from the 22 rounds of ammunition stored inside the hull

This would result in a vehicle weighing in at 12,060 kg, and as such almost perfectly equal to the expected 12 tonnes. When subtracting the two turret crewmen, all fuel and all ammunition, the weight would be of 11,340 kg; without the driver, it would logically be reduced to an empty weight of 11,260 kg.

The expected performances from this vehicle were to be a maximum speed of 3 km/h on the first gear, 12 on the second, 19 on the third, 31 on the fourth, 48 on the fifth, and finally, an impressive 73 km/h on the sixth gear. The average cruise speed on road was expected to be 40 km/h. Considering the reverse speed was assured by a gear inversor, the tank would be expected to reach the same speeds in reverse.

It was expected that, at ⅗ of the maximum engine power, the 300 litres fuel tanks would allow for 6 hours of continuous running, or a practical range of about 240 km. The vehicle was expected to climb a 70% slope, and be able to go down a slope of a similar degree while remaining controllable.

Artillery Version

In addition to the hull which would be used in the tank and anti-aircraft versions of the vehicle, Batignolles-Châtillon also designed an artillery version armed with a 105 mm in a fixed casemate. This version is known from a set of plans dated from June 1950, and it is not known if a version using the interleaved suspension design of the hull has ever been worked on.

A profile view of the artillery version; the hull was largely the same, but the turret was entirely replaced by a new fixed casemate. Source: Châtellerault archives

The casemate featured a sloped frontal plate and square sides; the front plate would have been 26 mm thick, with the sides and rear 20 mm thick. The casemate expanded beyond the rest of the hull and over the tracks, with a total width equal to the vehicle with tracks at 2.4 m, in order to increase the internal space allocated to the crew. At 2.175 m high, the vehicle would be only 5 mm higher than the tank version.

A front view of the artillery vehicle, showing the considerable overhang of the casemate over the tracks, necessary in order to increase internal space. Source: Châtellerault archives
A top view of the artillery version. The gun extended very little beyond the hull. Source: Châtellerault archives

The reason for a quite large casemate being needed was both the size of the 105 mm AU 50 gun and of the crew needed to operate it. The gun had a length of 3.096 m from the end of the muzzle brake to the breech. As such, it only had a very limited overhang in front of the hull, reducing the length of the vehicle to a mere 4.663 m. To operate it at a sufficient rate of fire, seeing as there was no autoloader, the casemate crew would be of four – a commander, a gunner, and two loaders – in comparison to the two-man crew of the tank version’s turret. Forty 105 mm rounds would be stowed within this casemate. Depression was reduced to a mere -3°, but elevation was a lot higher, at +67°, to allow for indirect fire.

Impressively, the additional weight was kept to a minimum in comparison to the tank. The vehicle’s weight without casemate crew, fuel and ammunition was noticeably lighter, at 10,730 kg, and even with the full crew, fuel and ammunition load, weight was expected to only reach 12,230 kg – in other words, only 170 kg more than the tank configuration. The engine, transmission and suspension were left unmodified, and the mobility was expected to largely be the same. Ground pressure was to be raised by a mere 10 grams per cm² on soft soil, reaching 0.695 kg/cm².

Prototype and Trials

The Batignolles-Châtillon light tank prototype was formally presented in June of 1950 in Nantes. Trials began at Satory in January of 1951. The vehicle was transferred to the STA in May 1951, with trials continuing until they were stopped in September.

A top view of the Batignolles-Châtillon 12t prototype without the turret test-weight present, with the turret ring empty and fully visible. A fueling port can also be seen on the rear right, as well as the ventilator on the front right. Source: Châtellerault archives
A side view of the same prototype, this time with the large, more than 3.5 tonne weight which was used to simulate a turret. Source: Châtellerault archives

In comparison to the vehicle on the plans, the prototype received another engine, a Mathis Type 8 GZ 8-cylinders aviation engine with 6,927 l. Its horsepower output is not known. The hull was not fitted with a turret, and instead received a 3,539 kg weight. The hull, without crew, ammunition or fuel, was weighed at 8,119 kg, giving the trial vehicle a total weight of 11,658 kg. It had a ground pressure of 0.640 kg/cm² on soft soil. The prototype also featured two return rollers, which were perhaps considered but not present on previous schematics.

The experimentation of the prototype was conducted by AMX, with a trials report produced in October of 1951. Sadly, only parts of this report have surfaced, and how exactly the Batignolles-Châtillon vehicle fared is unknown. The vehicle would, in all likelihood, have been the fastest out of all the 12t prototypes, and it appears it may have retained a fairly moderate weight even with the turret and full fuel and ammunition load. However, by this point, the AMX vehicle, which was highly satisfactory, was already adopted and entering production, and so it was highly unlikely the Batignolles-Châtillon vehicle would be ordered even if very high performing.

Conclusion – Too Late to the Party

The Batignolles-Châtillon 12t is notable in that it basically had two vastly different configurations during its life as a design, starting as a relatively large light tank with a centrally-mounted turret that was deeply modified, or likely even redesigned from the ground up, as a smaller and likely lighter vehicle with a turret mounted to the rear. The specifics of the design appeared to grant it an impressive maximum speed for the era, as well as a likely smooth drive. However, the vehicle was at least a year late, if not more, in comparison to the AMX and FCM vehicles, and with the AMX-12t already being a clear favorite by the time the Batignolles-Châtillon 12t was even completed, it had pretty much no chance of being adopted.

In recent years, the fairly obscure 12t has seen a regain of popularity in online circles, likely due to the popularity of the ‘Batignolles-Châtillon’ name due to the inclusion of first the 25t, and later some 12t-type vehicles in Wargaming’s popular online game ‘World of Tanks’. Two 12t-based vehicles exist in World of Tanks, the base Batignolles-Châtillon 12t and the ‘Bourrasque’ premium. Both are based on the interleaved road wheels, central-turret design, but while the 12t vehicle itself appears to at least somewhat try to replicate a realistic version of that configuration, the ‘Bourrasque’ is a fictional design combining this hull dated from 1947 to a modified version of the late 1970s TS 90 turret – one of the most egregious example of fake tanks present in Wargaming’s game.

Batignolles-Châtillon 12t 1947 with interleaved suspension. Illustration by Brian Gaydos.
Batignolles-Châtillon 12t 1947 with the SAMM anti-aircraft turret and interleaved suspension. Illustration by Brian Gaydos.
Batignolles-Châtillon 12t prototype. Illustration by Brian Gaydos.
Batignolles-Châtillon 12t 1950. Illustration by Brian Gaydos.
Batignolles-Châtillon 12t 1950 with the SAMM anti-aircraft turret. Illustration by Brian Gaydos.
Batignolles-Châtillon 12t 1950 artillery version. Illustration by Brian Gaydos.

1947 interleaved road wheels design Specifications

Hull dimensions (L x w x h) 5.05 x 2.40 x 1.24 m
Transmission Front
Suspension Torsion bars with interleaved road wheels
Road wheels 7
Track width 38.5 cm
Crew 3 (Driver, Gunner, Commander/Radioman)
Main Armament 75 mm gun (future 75 mm SA 50)/ 4x MG 151/20 autocannons (AA variant)
Ammunition stowage 12 already loaded + 38 rounds
Elevation & depression +13° to -6°
Loading mechanism 2 x revolving automatic loading system with 6 rounds each
Secondary Armament Coaxial 7.5 mm MAC 31 machine gun
7.5mm ammunition stowage 1,050 rounds
Hull Armor 40 mm equivalent (front), 20 mm (sides and rear), 10 mm (floor), uncertain but likely 10 mm (roof)
Turret Armor 40 mm equivalent (front), 16 mm (sides and rear), 10 mm (roof)
Produced 0

Finalized design (1950) Specifications

Dimensions (L x w x h) 6.472 x 2.40 x 2.17 m
Empty weight 11,26 0kg
Loaded weight 12,060 kg
Engine Mathis 18 GZ 00 aviation engine
Cylinders V7, 7-cylinder 6,827 L
Horsepower output 210 hp
Power-to-weight ratio in hp/tonne 17.5
Gearbox 6 forward speed with inversor
Maximum speed 73 km/h
Cruise speed 40 km/h
Fuel tanks 300 L
Range 240 km
Autonomy at ⅗ of maximum engine power 6 hours of continuous operations
Transmission Front
Suspension Torsion bars
Road wheels 4
Track width 370mm
Track pitch 135mm
Ground pressure 0.685 kg/cm² (soft soil)
10.2 kg/cm² (hard soil)
Main Armament 75 mm gun (future 75 mm SA 50)
Ammunition stowage 40 rounds
Elevation & depression +13° to -6°
Loading mechanism 2 x revolving automatic loading system with 6 rounds each
Muzzle velocity 1,000 m/s
Maximum armor penetration at 1,000m 170 mm at 90°
Secondary Armament Coaxial 7.5 mm MAC 31 machine gun
7.5mm ammunition stowage 1,050 rounds
Hull Armor 25 mm at 27° and 15° (upper front plate)
25 mm at 75° (mid-lower front plate)
15 mm at 20° (lower front plate)
15 mm (front floor)
10 mm (most of the floor)
19 mm at 25, 50, and 80° (lower, mid, and higher rear plates)
20 mm (sides)
10 mm (roof)
Turret Armor 40 mm equivalent (front), 16 mm (sides and rear), 10 mm (roof)
Produced 0

Artillery version (1950) Specifications

Dimensions (L x w x h) 4.663 m x 2.40 x 2.175 m
Empty weight 10,650 kg
Loaded weight 12,230 kg
Engine Mathis 18 GZ 00 aviation engine
Fuel Petrol
Cylinders V7, 7-cylinder, 6,827 L
Horsepower output 210 hp
Power-to-weight ratio in hp/tonne 17.2
Gearbox 6 forward speed with inversor
Maximum speed 73 km/h
Cruise speed 40 km/h
Fuel tanks 300 L
Range 240 km
Autonomy at ⅗ of maximum engine power 6 hours of continuous operations
Transmission Front
Suspension Torsion bars
Road wheels 4
Track width 370 mm
Track pitch 135 mm
Ground pressure 0.695 kg/cm² (soft soil)
10.2 kg/cm² (hard soil)
Crew 5 (Driver, Gunner, Commander/Radioman, two loaders)
Main Armament 105 mm AU 50
Ammunition stowage 40 rounds
Elevation & depression -3° to +67°
Muzzle velocity 570 m/s
Hull Armor 25 mm at 27° and 15° (upper front plate)
25 mm at 75° (mid-lower front plate)
15 mm at 20° (lower front plate)
15 mm (front floor)
10 mm (most of the floor)
19 mm at 25, 50, and 80° (lower, mid, and higher rear plates)
10 mm (roof)
Casemate armor 26 mm sloped (front)
20 mm (sides and rear)
Likely 10 mm (roof)
Produced 0

Test vehicle (1950-1951) Specifications

Dimensions (L x w x h) 6.472 x 2.40 x 2.17 m
Empty hull weight 8,119 kg
Additional weight 3,539 kg
Total weight without driver or fuel 11,658 kg
Engine Type 8 GZ aviation engine
Cylinders 8-cylinder 6,927 L engine
Gearbox 6 forward speed with inversor
Fuel tanks 300 L
Transmission Front
Suspension Torsion bars
Road wheels 4
Track width 370 mm
Track pitch 135 mm
Ground pressure 0.640 kg/cm²
Crew 1 (driver)
Hull Armor 25 mm at 27° and 15° (upper front plate)
25 mm at 75° (mid-lower front plate)
15 mm at 20° (lower front plate)
15 mm (front floor)
10 mm (most of the floor)
19 mm at 25, 50 and 80° (lower, mid, and higher rear plates)
10 mm (roof)
Produced 1


Les véhicules blindés français 1945-1977, Pierre Touzin, éditions EPA, 1978
French military archives of Châtellerault, made available by Colasix:
Service Historique de la Défense, Châtellerault 503 3H1 27
Service Historique de la Défense, Châtellerault 326 3H1 23
Service Historique de la Défense, Châtellerault 343 3H1 41

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