Designs of heavy tanks for breaking through fortified sectors began in 1916, initiated by Jean Baptiste Estienne, considered the father of French tanks. Work began in FCM factories. This was a ship-building company, but since the tank was planned as a land ironclad, this choice was not accidental.
The first prototypes of heavy tanks were build in December of 1917. Two vehicles, indexed Char 1A, weighed 41 tons and were protected with 35 mm of armour. The Char 1A was armed with a 75 mm gun in a rotating turret and two 8 mm machine guns. The difference between the two prototypes was in the transmission: one was mechanical, and one was electric. A third prototype was armed with a 105 mm howitzer. The crews were quite large, as they tended to be in WWI tanks: 12 men.
An improved heavy tank variant entered mass production, completed in February of 1918. This vehicle was indexed Char 2C, weighed 70 tons, and had up to 55 mm of armour. This made it the world's first mass produced tank with armour capable of withstanding artillery shells.
The size of the tank was very impressive: 10 meters long and 4 meters high. The length of the hull would enable the vehicle to cross anti-tank trenches and move freely in terrain pock-marked with high caliber artillery shell craters.
The 2C was armed with a 75 mm gun in a rotating turret, and 4 8 mm machineguns, one of which was placed in a turret on the back of the hull. Neither the main gun nor the machinegun turrets had 360 degree range, blocked by the tall roof of the engine compartment.
The tanks used two Mercedes-Benz engines, later replaced with two 250 hp Maybach dirigible engines, received from Germany as reparations.
The Char 2C was the first mass production tank that used an electrical transmission. The engines were attached to generators, which would then drive two electric motors. The tank could accelerate up to 17 kph. The crew was composed of 12-13 men.
10 Char 2C tanks were built in 1922. According to French tradition, each tank had a proper name, matching one of the provinces: Province, Picardie, Alsace, etc. From 1923, these vehicles were used by the 51st Heavy Tank Battalion, which was located in Le Bourget.
Original article available here.