AMR 35 - Variants and Projects - Radio Communication Vehicles - Renault YS

Renault YS

The Renault YS was a version with a large superstructure but without turret, serving as a higher command vehicle. The specifications for such a type had been issued on 9 January 1931: it was then named the Type M. Renault had built two prototypes of boiler plate, based on the AMR 33 chassis, in 1933. General Darius Bloch, head of the technical section of the supreme command, had formed a favourable opinion on these in September 1933 and during a session of the Conseil Consultatif de l'Armement in January 1934 had desired that a dozen be acquired. On 10 April 1934 the order was signed for ten voitures de reconnaissance tous terrain blindés, to be delivered before 31 December 1934, the uncommon term "all-terrain armoured reconnaissance vehicles" intending to obscure the fact that they were command vehicles. They had the factory designation Renault YS.

The prototypes had already been rebuilt with the AMR 35 suspension: to avoid a future disappointment Renault explicitly established in the contract that due to the more robust and heavier AMR 35 chassis to be used, the series vehicles would have an inferior performance: the weight would increase from 3.5 to 4.3 tonnes and maximum speed would drop from 60 to 55 km/h; average road speed from 40 to 35 km/h.

The ten vehicles, N° 84252 - 84261, were only delivered between 14 and 16 December 1937, after having been tested between 1 September and 22 November 1937 by the Commission de Vincennes. The delay of three years could not be entirely be blamed to Renault: the different Arms for which the YSs were intended each had special requirements for the combinations of (short and long range) radio sets to be built in. Some of the latter even yet had to be developed — the first specifications were only issued in June 1935 — and afterwards for each subtype a special interference suppression had to be applied and thoroughly tested. For these tests the original two prototypes were used.

Of the ten, the Cavalry received four vehicles (reduced from an original planned allocation of six) using the so-called "Type C" equipment: a combination of the ER (Émitteur-Recepteur)26 ter and the ER29. Two of these were assigned to the 2nd and 3rd GAM (Groupe de Automitrailleuses) each. The Infantry also received four. Two of these had the "Type G" equipment: a combination of the ER51 modèle 1935 and the R15 (the last a receiver set only). These so-called type chars vehicles, intended for tank units, were assigned to the 507e and 510e Régiment de Chars de Combat. The two others used a "Type E" equipment with a combination of the ER 26 ter and the R15; these were assigned to mechanised infantry units, the 5e and 17e BCP (Bataillon de Chasseurs Portés). Two Type E-vehicles were also received by the Artillery Arm and assigned to the 1er and 42e Régiment Artillerie.

The versions differed externally in the type of antennae (frames) used. As a whole the type had a very different configuration from that of the AMR 35: in the raised front and superstructure the engine was placed in the front, the driver was seated to the right with the vehicle commander to his left; and behind was a large compartment for two radio operators with a high double hatch in the back. The Artillery used only a single operator in exchange for more supplies. The unloaded weight was considerably higher than predicted, at 5950 kilogrammes. Fully loaded, including about 0.8 tonnes of radio equipment, weight increased to about 7.5 tonnes, hundred kilogrammes higher than the acceptable suspension maximum indicated by Renault. Despite the fitting of a second fuel tank, the range decreased to 150 kilometres and the reliability of the type was low with much breakage of the road wheel axles.