The AMX-30 is a main battle tank designed by Ateliers de construction d'Issy-les-Moulineaux (AMX, then GIAT) and first delivered to the French Army in August 1966. The first five tanks were issued to the 501st Régiment de Chars de Combat (Tank Regiment) in August of that year. The production version of the AMX-30B weighed , and sacrificed protection for increased mobility. The French believed that it would have required too much armour to protect against the latest anti-tank threats, thereby reducing the tank's maneuverability. Protection, instead, was provided by the speed and the compact dimensions of the vehicle, including a height of 2.28 metres. It had a 105 mm gun, firing a then advanced high-explosive anti-tank (HEAT) warhead known as the Obus G. The Obus G used an outer shell, separated from the main charge by ball bearings, to allow the round to be spin stabilized by the gun without spinning the warhead inside which would disrupt jet formation. Mobility was provided by the HS-110 diesel engine, although the troublesome transmission adversely affected the tank's performance. In 1979, due to issues caused by the transmission, the French Army began to modernize its fleet of tanks to AMX-30B2 standards, which included a new transmission, an improved engine and the introduction of a new OFL 105 F1 fin-stabilized kinetic energy penetrator. Production of the AMX-30 also extended to a number of variants, including the AMX-30D armored recovery vehicle, the AMX-30R anti-aircraft gun system, a bridge-layer, the Pluton tactical nuclear missile launcher and a surface-to-air missile launcher. It was preceded by two post-war French medium tank designs. The first, the ARL 44, was an interim tank. Its replacement, the AMX 50, was cancelled in the mid-1950s in favor of adopting the M47 Patton tank. In 1956, the French government entered a cooperative development program with West Germany and Italy in an effort to design a standardized tank. Although the three nations agreed to a series of specific characteristics that the new tank should have, and both France and Germany began work on distinctive prototypes with the intent of testing them and combining the best of both, the program failed as Germany decided not to adopt the new French tank gun and France declared that it would postpone production until 1965. As a result, both nations decided to adopt tanks based on their own prototypes. The German tank became the Leopard 1, while the