In different ways, the military and engineers come to the creation of perfect military equipment. It happens that she appears too late and does not participate in battles. Unless its creation gives a certain experience …
“It’s better to do it once on time than twice correctly.”
Saying of managers and engineers
Tanks of the world. Not so long ago, we published on VO material about the French Renault FT-17 tank. I don’t know how timely it was, but the amount of information used in it was clearly not too great. Therefore, in this publication we will try to deepen this topic a second time. The fact is that a tank, any tank, is primarily an all-terrain chassis. And having such a chassis at hand, the military immediately wants to put a larger caliber cannon on it. And all because the problem of moving artillery to support any offensive through the trenches on the Western Front was defined by the French army as central back in 1915, and it was then that it turned out that it could only be solved with the help of the same tanks. Or rather, quite heavy guns mounted on the chassis of tanks. Well, how it happened in the case of the Renault tank, we will tell you today …
Need is the world’s best customer!
It so happened that the inability of horse-drawn wheeled vehicles to cross the no-man’s land of the battlefield became apparent very quickly, as well as the fact that only tracked vehicles can do this. Then the Ministry of Ammunition and the High Command of the French Army studied almost all possible options for moving artillery using tracked vehicles. As a result, it was concluded that there are only two suitable chassis: Renault FB and Schneider CD. The tank, and in fact, the Saint-Chamon self-propelled gun, had a speed on the battlefield of only 2.5 km / h, so it was considered unsuitable for a quick response to changes in the tactical situation.
This is what the very first self-propelled gun based on the FT-17 looked like. It is difficult to imagine something more ridiculous …
But the production of the Renault FT light tank in 1917 opened up the possibility of solving the problem of transporting light field guns on the chassis of this particular tank. By May 1918, research was already under way on the use of reckless FT tanks equipped with light cannons, such as the 75-mm Mle 1897 field gun and the 105-mm Mle 1913 howitzer. At the end of August 1918, the Supreme Headquarters of the French army approved these studies and demanded immediately to issue a ready-made sample of such a machine. And already on September 3, 1918, the specification for the self-propelled guns based on the FT-17 was issued with a 75-mm Mle 1897 field gun, a crew of 4 (driver plus crew) and 100 rounds of ammunition, with a total weight of 5-6 tons. According to this specification, three prototypes of the future self-propelled gun were built. Moreover, the goal was to create such an ACS that could be used both as a counter-battery fire weapon and as an anti-tank weapon on the battlefield.
Driver’s seat and ammunition rack
When other simplicity is worse than theft!
The first self-propelled gun produced was developed by Renault and tested in August 1918, after which it was submitted for official testing at the French army’s training ground in Bourges on September 18, 1918. The car was made extremely minimalistic. The gun could only fire through the aft part of the self-propelled guns, and the barrel moved in a vertical plane from -4 ° to + 24 °, which limited the maximum range of the 75-mm gun. Details of how the azimuth guidance device worked are unknown. The driver had to leave the car before firing, and there was a pair of unprotected seats to accommodate two gun crews. In the boxes above the engine compartment, 40 shells were stored. Although the SPG turned out to be a fairly stable gun platform and met the requirements for cross-country ability and mobility on poor soil, poor ergonomics and smaller ammunition than indicated in the specification led the French army to abandon this SPG.
Renault also installed a 105-mm howitzer on the FT tank chassis. But even less is known about this version than about the first.
The failure with the Renault self-propelled guns led to the fact that the army command demanded from the Vincennes Arsenal to create a unit capable of carrying 150 shells (half a day of firing) and use the Gramme naval pedestal mount for a 75-mm cannon to mount a gun on a tank chassis. The front of the FT chassis was removed and the gun was mounted on a reinforced floor. The driver was moved to the center of the vehicle, similar to the failed Renault FT-75 BS prototype. The artillery crew had an unprotected bench in the rear of the chassis. The prototype had a rotation angle of 360 ° and an elevation angle of -8 ° to + 40 °, although at angles above + 10 ° the gun had to shoot through the rear of the vehicle. Ammunition of 120 rounds. The first and only prototype was completed on October 9, 1918.
Transportation of the calculation to the ACS STA
The third model is the best
The latest development of the FT ACS was the “section Technique de l’artillerie” (STA), a much more sophisticated design in which the engine was placed in the central part of the hull, and the rear part was opened in such a way as to make room for the calculation of the gun, which was installed for shooting over the front of the car. The angle of rotation of the gun is from -5 ° to + 41 ° when aiming at 11 °. ACS could carry up to 90 rounds of ammunition.
The crew fires a Hotchkiss machine gun at an air target
This SPG was apparently built by Renault and sent to Bourges at the end of October 1918. On later modifications of the STA ACS, the rear platform was expanded, folding supports were added to prevent the vehicle from swaying during firing, and a Hotchkiss machine gun for self-defense.
SPG front view
One of the problems of operating ACS with rapid-fire guns was the laboriousness of delivering ammunition to them. The Renault company took this into account and released a prototype of a tracked vehicle for transporting ammunition with a cargo compartment of 1.5 mx 1.05 mx 0.9 m. Compared to the FT tank, the length of the tracks was increased. But only one prototype was produced, as it turned out that the existing Renault FB and Schneider CD could carry much more ammunition.
The first variant of the FT-75 BS
How two generals did not share one self-propelled gun …
Well, then general squabbles began. The general, inspector general of artillery, opposed these self-propelled guns, since, in his opinion, towing guns with tracked tractors was the best solution. He managed to convince the commander-in-chief, General Pétain, who opposed the production of a trial batch of four self-propelled guns, which were proposed by the Ministry of Ammunition on November 6, 1918. However, the self-propelled guns also had supporters. General Saint-Clair Deville, Inspector General for Artillery Armaments, strongly supported the idea of self-propelled artillery in December 1918. Pétain decided to avoid confrontation and ordered additional tests of the prepared prototype. But since by this time the war had already ended, and the FT tank was considered almost obsolete, the release of the STA self-propelled guns based on it was considered irrational.
The FT-75 BS tank goes through the forest
Another attempt: a cannon in the body
However, another attempt is known to arm the FT-17 tank with a larger-caliber gun, and now it was more successful.
View of the tank FT-75 BS on the right
It is known that in 1918 the FT-17 was produced with both a machine gun and a 37 mm cannon. Moreover, it was noted that, although the 37-mm cannon was quite capable of hitting light fortifications, in order to attack more solidly fortified positions, it needed a larger caliber gun. General Etienne, “the father of the French Panzer Corps”, clarified that the “fire support” vehicle should be developed on the basis of the FT, but with the 75mm Blockhaus Schneider (BS) cannon, which was originally developed as a short-range fortress cannon, and then they began to put on the tanks “Schneider” CA1. Despite the fact that the 75 mm BS cannon had a short range, its size, low weight and high rate of fire made it attractive as an auxiliary weapon and on FT tanks.
The performance characteristics of this gun were as follows:
Caliber 75 mm
Barrel length L / 9.5
Angles of ignorance vertically from -10 ° to + 30 °
Horizontal aiming angle 60 °
Projectile weight 5.55 kg
Initial speed 200 m / s
Maximum firing range 2 100 m
Effective range 600 m
In early 1918, two different prototypes were built and tested. In the first sample, the driver was seated on a raised platform in the center of the tank, and the gun was placed opposite it very low in the front of the tank. As a result, due to the limited visibility from the driver’s seat, this car was difficult to control. And it was simply impossible for two gunners to service the gun in the cramped front of the vehicle. As a result, the project was rejected.
Seen on the FT-75 BS from the left
The second model was successful, but was unnecessary!
The second prototype was built by the organization “Champlieu” and was a complete redesign of the standard FT tank, replacing the turret with a fixed wheelhouse. It turned out that the weight gain was limited to 200 kg (compared to the FT tank) with 35 rounds of ammunition available. This vehicle entered service as the Renault FT-75 BS, and in mid-May 1918, about 600 vehicles were ordered. It was planned that each company of FT tanks should have one FT-75 BS as a support vehicle, and about half of the order was to replace the failed Schneider CA1 tanks. The first production FT-75 BS was completed at the end of July 1918.
However, before the armistice in November 1918, only 75 BS vehicles were delivered, and, as far as is known, none of them took part in the hostilities. After the armistice, orders were drastically reduced, and in 1919 only 29 were produced.
These tanks survived to the point that they were captured by the Germans in 1940!
Many of the FT-75 BSs after World War I were sent to French units in North Africa and Syria (Levant). Some took part in the fighting in the French colonies. Two tanks were discovered by the Allies in Tunisia in 1942 after Operation Torch and the invasion of North Africa.