letter from Louis Renault to Jules Breton, Under Secretary of State for War

Louis Renault saw orders for his FT tank take off in the first quarter of 1917 and committed to delivering 2,000 tanks between July and November 1917. This implies a production of 400 tanks per month and an urgent need for raw materials. He therefore explained his needs to Jules Breton, in the letter that is transcribed below, outlining a real industrialization plan inspired by the Ford factories.

How do you manage to produce so many FT tanks?

How to succeed in producing so much "The raw materials must reach the factories within a suitable time and, moreover, the factory must be able to obtain the following assistance from outside: the gears for the speed reducers must come from outside, forged and roughened from lathes, the factory must also receive forged crankshafts from outside. The Paul Girod steelworks in Ugine should supply the domes (NDA: turrets) within the appropriate time frame; the Holtzer company should supply the gear steels and even provide a large part of the forged and stamped gears. The armor plates will have to be supplied perforated and cut to size and treated. The Paul Girod steel mills could perhaps take care of the 6 and 8 plates, and the supplier for the 16 plate would have to be found (NDA: this would be the Fichet company, specialized in safes). Finally, 150 turners, 50 planers or milling machines and 100 fitters would have to be made available to the Renault company. "FT tanks?

Production of Renault FT tanks

Production of Renault FT tanks in Lyon, in the Berliet factories, 1917

Credits: M. Berliet Foundation

Difficulties to produce so many FT tanks so quickly

But the lack of raw materials will not allow the subcontractors to deliver on time, and it will be necessary to turn to Great Britain to obtain the necessary armor steels, not always of good quality (bad case hardening, 40% of rejects). The absence of steel is such that the large pulley of return, located at the front of the tank, is made of wood!

The lack of manpower will make that in 1918, one will think of calling upon the voluntary prisoners of war to launch the construction of 300 heavy tanks of 70 tons

However, despite all the difficulties encountered, Renault succeeded in delivering nearly 200 light tanks per month from March 1918, including 278 in July.

Berliet and Somua also participate in the production of FT

Chart FT during the first world war

Chart FT during the first world war

That month, the Ministry of Armament increased the number of Renault FTs on order to 4,700. In order to speed up production, Louis Renault was invited in April 1917 to look for other French and American manufacturers to produce his FT under license. The French companies Berliet (NDA: Berliet produced its own armor, machined its own turrets and assembled its own engines, which were also sold to SOMUA and Delaunay-Belleville), SOMUA and Delaunay-Belleville thus began mass production of the light tank for 3,880 units, in addition to the 3,940 ordered from Renault, for a total of 7,820 FTs.

Reference : Extract from the book by Stéphane Ferrard, a defense journalist who died in 2015, Technologie et Armement, published in June 2004. Reprinted by Marc Chassillan in the book Histoire d'ARQUUS.