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Cold War French Prototypes

Chasseur de Char de 76.2mm AMX sur châssis S35

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France (1945)
Tank destroyer design – None built

Following the liberation of France, which started in June 1944 and was mostly concluded, with the exception of areas towards Alsace and some western ports by the end of August that same year, rebuilding France’s military industry quickly became a new priority for the French government. Once a world leader, the French military industry had been considerably weakened by years of German requisitions and Allied bombings. If France wanted to retain an important and independent place on the world stage, a healthy military industry would prove a massively useful tool.

The first phases of the French military industry getting back on its feet often took the basis of pre-1940 vehicles being modernized to suit modern needs (such as the Panhard 178B, the first armored fighting vehicle produced by France post-war) or used as the basis for vehicles swaying away from the original hull’s role. Within these, one could name three tank destroyers projects which were submitted by the Atelier Mécanique d’Issy-Les-Moulineaux (AMX) in November 1945, mating the hulls of two pre-1940 French tanks, the R35 and S35, with the British 17-pounder anti-tank gun.

A ¾ front view of the S35 tank destroyer, showing the general shape of the casemate, driver’s hatch, and the large rear ammunition locker. Source: Mémoire des hommes

AMX’s proposals

There were three different proposals for 17-pounder-armed tank destroyers based on old French hulls. Two were based on the Renault R35 hull, one with a front-facing, and one with a rear-facing gun. These both dated from 8th November 1945. The third project actually predates both, with two documents, a ¾ top view of the vehicle dated from 11th October 1945, and a set of plans dated from 10th October.

As for the choice of the old French tank hull, while a number of S35s were seized after the liberation of France, this number remained limited, and the project was most likely never seriously intended for production. Instead, it likely was a ‘proof-of-concept’ and a way for AMX’s engineers to get back into designing armored vehicles on the basis of familiar components. One could argue that, in comparison to the R35, the S35 would provide a more viable basis, being a larger vehicle more suited to mount a heavy gun the like of the 17 pounder.

Overall superstructure

A front view of the S35 tank destroyer, showing the offset gun, driver’s post, and location of the most important ammunition stowage. Source: Mémoire des hommes

Mounting the 17-pounder on the hull of the Somua S35 obviously required some major changes to the superstructure and hull, though perhaps more moderate than on the lighter and smaller base of the R35. In the case of the S35, pretty much the whole front section of the upper hull and turret would be removed in order to accommodate the 17-pounder and fighting compartment. However, the engine compartment and rear part of the hull would be kept pretty much unchanged.

Overall, removing the turret would free up 2,350 kg. A further 1,850 kg of upper hull armor plates would be removed as well, and an additional 200 kilos of equipment. With all of this removed, the Somua, before receiving any of the additional equipment, would go down from 20,000 to 15,600 kg.

In place of the previous front upper hull, a new large armored superstructure would be installed. This was a fairly high superstructure, though, at a maximum height of 2.25 m, the tank destroyer would overall be shorter than the S35 tank. This superstructure, however, retained a bulky and massive silhouette the tank would have lacked. To the front, the sides angled forward towards the gun, which was offset to the right of the hull. The weight of this armored superstructure would be 2,000 kg, which was a lot more than on the R35 proposals. Though this may partially be explained by the superstructure simply being, to an extent, larger, it was also likely better armored to an extent – though the vehicle’s armor protection would most likely still have been lower than on the S35, not even accounting for the open top.

A side cutaway view of AMX’s S35 tank destroyer, showing the considerable length of the vehicle, of which an ample proportion was represented by the barrel. Source: Mémoire des hommes

This new casemate housed the British 17-pounder anti-tank gun, one of the most powerful anti-tank guns fielded by the Allies during the Second World War. In the form mounted in the tank destroyer, it weighed 1,630 kg. The gun was installed quite far forward in the hull, so as to leave sufficient internal space between its breech and the engine compartment for the vehicle crew. As a result, it overhanged the front of the hull by a whopping 2.86 m, bringing the length of the vehicle to 7.93 m. This gun, placed far to the front, also brought the center of gravity forward by 0.48 m, or from about the middle of the fifth roadwheel from the front to about the middle of the fourth roadwheel from the front. The gun had a field of fire of 29° to the right, and 16° to the left. It could elevate to 22° and depress to -9°.

The vehicle featured a 250 kg rounded mantlet, similar to the two R35 proposals. Unlike those two, the larger size of the S35 hull meant there was little overhang of the casemate over the engine compartment; though the casemate featured a form of bustle which contained an ammunition locker. The engine was still basically free to access. The vehicle retained the same powerplant as a conventional S35, a Somua 8-cylinders 190 hp engine. However, the S35 tank destroyer would be somewhat heavier than the S35, with an estimated weight of 21,658 kg, which would have resulted in a power-to-weight ratio to drop to about 8.8 hp/tonne, and the vehicle could overall be expected to be somewhat less mobile than the original S35 tank.

Internal arrangement, ammunition stowage, and crew

The plans of the S35 tank destroyer, as with the two R35 projects, depict it with a crew of only two – a driver sitting on the left of the vehicle and given a vision hatch through the new armored superstructure, and a commander which would presumably also operate the gun all by himself. It is very unlikely such a crew configuration was actually intended to be used. More so than on the R35 projects, the armored superstructure of the S35 allowed for enough place to accommodate at least one, if not two, additional crewmen, which would be more than helpful to operate a gun such as the 17-pounder in optimal conditions.

A top view of AMX’s S35 tank destroyer, showing the internal space that would be allocated to the crew between the massive gun and the engine compartment. Though portrayed with two crewmen, it is likely the vehicle would realistically have had a larger crew. Source: Mémoire des hommes

Two different ammunition lockers were provided for the vehicle. One was located to the right of the driver, below the gun’s breech, and accommodated 24 shells. A larger ammunition rack was installed in a form of bustle formed by the armored superstructure towards the rear, which would contain 54 shells. Finally, four shells would be stored on each side of the armored superstructure to form ready-racks, giving the vehicle a total ammunition carrying capacity of 86 rounds – or 1,978 kg of ammunition, to which one may add 200 kg for the weight of the ammunition locker and racks. This meant that firing all of the vehicle’s ammunition would considerably lighten it up, by more than 9%. This was not, however, as impressive as the front-facing R35 tank destroyer proposal, which would lighten up by around 13% after firing all of its ammunition.

Conclusion – Not a way you want to use a Somua’s hull

This S35 project could be argued to be the most reasonable and realistic design out of the three which were proposed by AMX’s engineers in late 1945. This was simply due to the fact the larger S35 hull would provide a far more viable basis for a large anti-tank gun such as the 17-pounder in comparison to the R35 hull, which would struggle to accommodate such a gun in a way that would make its operation viable. Nonetheless, it remained an obsolete concept. A fairly slow, not amphibious nor airborne, open-topped tank destroyer would have served as an anachronism in the post-war battlefields, had it been chosen for production. This would not, however, be the case, with the few remaining Somua S35s in French hands continuing their service as cavalry tanks until 1946 in the 13ème Régiment de Dragons, and even as gendarmerie vehicles for some years in French North Africa.

Wargaming’s S35 CA, fictionally armed with a 90 mm gun. Source: youtube

The Somua S35 tank destroyer would likely have remained an obscure project in the archives of AMX, were it not for its introduction in Wargaming’s World of Tanks as the “S35 CA”. Even for what was only a blueprint, the vehicle could be modified by the player into an ahistorical configuration there, by replacing the 17-pounder by a 90 mm anti-aircraft gun. From the start, the vehicle is also powered by the 220 hp engine intended for the S40, and is later given a so-called “S40 Bis” 260 hp engine. This is also wrong compared to the historical configuration of the vehicle, and was obviously added as a gameplay element, disregarding the historical project – a pretty systematic policy for Wargaming, which many other French paper projects, the likes of the AMX-40, have suffered from as well.

The AMX S35 tank destroyer in a fictional French post-war scheme. Illustration created by Pavel “Carpaticus” Alexe on the basis of work by Tank Encyclopedia’s own David Bocquellet

Chasseur de Char de 76.2mm AMX sur châssis S35 specifications

Dimensions (L x w x h) 7.93 x 2.05 x 2.25 m
Weight in battle order 21,568 kg
Engine Somua 8-cylinders 190 hp engine
Power-to-weight ratio 8.8 hp/ton
Armament 17-pounder anti-tank gun
Ammunition stowage 86 rounds
Crew Uncertain (a driver and commander for sure; likely a loader, perhaps a gunner)
Gun traverse 16° to the left, 29° to the right
Gun elevation +22 to -9°

Sources

4 replies on “Chasseur de Char de 76.2mm AMX sur châssis S35”

What is the top speed? Also, if it is fairly mobile would it be able to hold off the Germans in the 1940 invasion of France for a little bit?

As the standard S-35 tank was 40kmh on road, 18kmh cross-country, with the same engine and 2 tons lighter, I suspect this would be doing 35kmh on road and 15kmh cross-country at best.

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