Char Moyen AMX 40 Historical Info . 1940 CHAR MOYEN AMX 40In March 1940 , the Workshop of Issy - les - Moulineaux was studying a new medium tank of cavalry , the successor of the SOMUA S - 35 and the S - 40 . The design was never built , due to the Fall of France in June 1940 . Description . The AMX 40 Cavalry was designed as a medium tank , modelled along very futuristic lines . Its rounded hull offers only oblique surfaces ; the undercarriage consists of four road wheels which was very modern for a 1940s tank . Its general hullform resembles that of postwar tanks . The tank had a cast steel body , 60mm front armor , side 50 to 30 mm and 40 mm to the rear . Length 5 . 30 m , width 2 . 45 m The chassis was composed of four - wheel drive twin 82cm in diameter protected with side shields . The two rear wheels are driven , which could allow the movement without the tracks . There were no return rollers ; the drive sprocket is at the rear . Fuel tanks placed above the tracks were expected to help strengthen the lateral protection ( the AMX - 40 was to be diesel - fueled ; unlike gasoline , diesel is not flammable at room temperature ) . Engine The AMX was expected to be powered by a diesel engine of 160 hp , low compared to the SOMUA ' s 190 hp and the S - 40 ' s 220 hp engines , for a vehicle with an estimated weight very close to the SOMUA ( nearly 20 tonnes ) . However , the rotation system could save significant weight and provide good performance despite the power deficit . As mentioned earlier , the choice of diesel fuel improves safety . Turret and armament The two - man turret casting has an ovoid shape reminiscent of the future Russian tanks of the T - 54 / T - 55 family . Access was to be through a 60cm - diameter circular hatch on the back of the turret . The hatch follows the general shape of the turret , which has no protrusions except for two openings in the rangefinder . Visibility was to be provided by a panoramic periscope on top of the turret . No slot vision seems to have been planned . The solution is attractive in terms of protection , but the concentration of the tank ' s visibility into a single element would have adverse consequences in the event of damage to the periscope . The main armament was expected to be an SA 35 47mm cannon , placed on the axis of the turret . Turret rotation was hydraulic , rather than hand - cranked . Breaking with the custom of one - man turrets , the AMX - 40 was to have a dedicated gunner along with the commander in the turret . Both occupants sat on a swivelled strap with the turret gunner on the left and the commander on the right . In addition to the 47mm gun , the tank had a secondary armament of two 7 . 5 mm machine guns - one co - axial with the main gun for close defense , and one on a retractable swivel joint in a compartment behind the turret for anti - air defense . The tank could hold up to 156 rounds of 47mm , distributed in the periphery of the turret in rotating part lockers , to facilitate access to ammunition . The ammunition supply is higher by almost 50 % than in the SOMUA . The hull The driver was centrally located in the front , with the dashboard is in the center of the steering wheel driving , such as how the Leclerc has not innovated on that . The driver ' s position is surrounded on both sides of a storage system chain for around 30 magazines of 7 . 5mm ammunition . This system used to access all of the stock without moving . Magazines are positioned in the turret for immediate use . The AMX 40 is as a potential successor to SOMUA S 35 . The S 40 S 35 which is only improved , particularly at the undercarriage , can no longer ensure a transitional role . Compared to SOMUA , this prototype ' s dimensions are nearly the same . The AMX is slightly shorter and less high but wider 33 cm which should improve its capabilities in all terrain . Another Story of the Char Moyen AMX 40 by : Antoine Misner In March 1940 , the Issy - les - Moulineaux Workshop exploring a new medium tank cavalry successor char SOMUA S - 35 and possibly the S - 40 . Brief description The AMX 40 cavalry is as a medium tank to look modern . The rounded shield offers only oblique surfaces and undercarriage of four major road wheels give it an appearance that contrasts strongly with the tanks in 1940 . Its general forms recall those already tanks after the war . The crew of three men , a pilot , and for ensuring a shooter likely function tank commander . Caisse cast steel front guard 60mm side 50 to 30mm , 40 mm at the rear . Length 5 . 30 m , width 2 . 45 m The undercarriage has four wheel drive twin 82 cm diameter protected with side shields . The two rear wheels are driven , which could allow movement without caterpillars . No return rollers , drive sprocket at the rear . Arranged above the chassis fuel tank contribute to strengthen the lateral protection ( The Gas oil , unlike gasoline flame at room temperature ) . Engines The AMX should be powered by a diesel engine of 160 hp . The engine may seem a little low , only 160 HP while SOMUA has 190 hp and the engine of the S 40 is provided with 220 hp . The estimated weight should be very close to the SOMUA ( almost 20 tons ) . The rotation can definitely save weight and provide a significant performance quite correct despite the power deficit . As mentioned above , the choice of fuel significantly improves the security of the machine . Turret and armament The turret casting seater has an oval shape that is reminiscent of future Russian tanks Family T - 54 T - 55 . Access is by a circular hatch 60 cm in diameter at the rear of the turret . The flap has the general shape of the turret which has no protrusion except the two openings of the rangefinder . The visibility is ensured by a panoramic periscope on top of the turret . No slot vision seems to have been planned . The solution is attractive in terms of protection , but the concentration of the entire vision of a single element can have adverse consequences for decommissioning the unique periscope . The main armament is a 47mm gun SA 35 . The barrel is disposed in the turret axis . Rotation is provided by hydraulic system . The two occupants were sitting on a strap system with swivel turret gunner left for right . The secondary armament of two 7 . 5 mm machine guns . The first coaxial to the barrel is intended to close defense . The second retractable and mounted on ball is placed in a compartment behind the turret and must defend against aircraft . The supply is 156 rounds of 47mm . Storage is distributed in the periphery of the turret , part rotating racks , part rocker lockers to facilitate access to ammunition . The ammunition supply is higher by almost 50 % SOMUA Case The pilot occupies a central position in the front , the dashboard is placed in the center of the steering wheel , like what the Leclerc has not innovated on this point . The cockpit is surrounded on either side of a storage system that holds about 30 chain chargers 7 . 5 mm . This system allows for access to the entire stock without moving . Chargers are positioned in the turret for immediate use . The AMX 40 is presented as a potential successor to SOMUA S 35 . The S 40 is only 35 S improved , especially at the undercarriage , not providing a transitional role . Compared to SOMUA , dimensions are about the same . The AMX is slightly shorter and less high but wider 33cm which should improve its off - road capabilities .