Renault UE Chenillette - Description

Description

The Chenillette ("small tracked vehicle") or tracteur blindé ("armoured tractor") as Renault preferred to call it, is indeed a very small vehicle: just 280 centimetres long, 174 cm wide and having its highest point at 125 cm; the roof is only 103 cm high. Its cargo carrying capacity is rather limited. There is a rectangular armoured bin at the back, 145 cm long (its length corresponds to the width of the vehicle as a whole), 60 cm wide and 36 cm high, able to hold a load of about 350 kg (lower than the original specification of 500 kg); unloading is made easier by the possibility to tilt the bin; the back plate then hinges downwards, forming a slope on which cargo can slide to the ground. The main cargo is carried by the tracked trailer, a close copy of the British type, with a length of its bin of again 145 cm, a width of 110 cm and a height of 35 cm; weighing itself 775 kg, it can hold a load of about 600 kg — whereas the specification had asked for only 400 kg. The tracks can be removed for road transport; there are two road wheels per side.

The bin forms the back compartment of the vehicle; the larger front compartment is for the crew and engine. The four-cylinder 38 hp engine is positioned in the centre, with the driver to its left and the commander to its right. The gear box (six speeds forward, two reverse), differential and transmission are placed in front of the engine. These mechanical parts are placed under two projections on the otherwise very steeply sloped armour of the glacis; these can be retracted for maintenance of the mechanical parts. Each crew member, sitting below a hatch that is the only way of entrance or exit, has a fuel tank behind its seat, together having a total capacity of 56 litres, allowing for a range of a hundred kilometres. The exhaust pipe runs in front of the commander to the right ending in a silencer on the right side of the vehicle; in later production vehicles an armoured cover was added; as it tended to overheat a later variant of this cover had cooling slits.

To reduce the height of the vehicle it has been made impossible for the crew members to retract their heads under the roof. To protect these vital parts two hemispherical armoured hoods (calottes) have been fitted. These have vision slits but to improve the field of vision the front section of these hoods can like a visor be pivoted backwards over the back section. As otherwise a bar between the roof and the glacis would have hindered entrance, the forward hinging glacis hatches have an extension forming the roof section that fits around the front part of the hood; if the hood is retracted and the hatch opened, a larger entry space is thus available. An interesting feature of the vehicle is the internal communication system used. When the hoods are closed, the two crewmen, separated by the engine between them, cannot directly communicate; neither internal nor external radio communications are possible, as there are simply no radio sets fitted. A system of white, blue, green and red lights, that can be made to shine continuously or flicker, is used by the commander to direct the driver when buttoned up, based on a predetermined signal code:

• Forward: continuous white light.
• To the left: continuous blue light.
• To the right: continuous green light.
• Backwards: flickering white light.
• Slow down: flickering red light.
• Stop: continuous red light.
• Decouple the trailer: alternating white and red light.
• Tilt the bin: alternating green and white light.

The suspension system closely resembles the Vickers type. There are 18.4 cm wide tracks with 131 small links and three bogies per side, sprung by small leaf springs, carry each two small road wheels. The prototype had an armoured plate protecting this assembly but it was omitted on the production vehicles to save weight, leaving only two elongated beams to brace the whole. Likewise the sprocket was simplified: the prototype's had been a closed disk, the production type had six circular holes; later vehicles were fitted with a wheel with six spokes. There are two return rollers. In all the suspension system is flimsy and vulnerable. This is compensated by limiting the official maximum speed to thirty kilometres per hour, although the combination of a weight of just 2.64 metric tons with an engine power of 38 hp would allow for a higher speed; during testing 36 km/h was attainable. This also reduces the chance of accidents while towing the trailer; fully loaded the road speed is reduced to 25 km/h, the cross-country speed to ten km/h. The wading capacity is thirty centimetres; the trench crossing capacity 120 centimetres. The turning circle is three metres; a slope of 50% can be climbed.

The value of the Chenillette as an armoured fighting vehicle was limited. In French service, the Modèle 31 carried no armament, although some later vehicles had attachment points for a removable AA-machine-gun to be fitted — but this had to be operated from outside the vehicle in an awkward crouched position due to its low height. For the crew to use personal weapons through the hatches while sitting inside the hull was highly impractical. Consideration had been given to arming it with a machine-gun, but the Direction de l'Infanterie feared that if such a weapon were mounted, the UE would be misused as a light tank rather than being dedicated to its correct tactical resupply role. Likewise the armour protection was minimal. The vertical plates had a thickness of nine millimetres, the other plates, all riveted, were six millimetres thick, just enough to stop normal rifle bullets and shell fragments.