Light tank

A light tank is a tank variant initially designed for rapid movement, and now primarily employed in the reconnaissance role, or in support of expeditionary forces where main battle tanks cannot be made available. Early light tanks were generally armed and armored similar to an armored car, but used tracks in order to provide better cross-country mobility.

The fast light tank was a major feature of the pre-World War II buildup, where it was expected they would be used to exploit breakthroughs in enemy lines created by slower, heavier tanks. Numerous small tank designs and "tankettes" were developed during this period and known under a variety of names, including the "combat car".

The light tank has been one of the few tank variants to survive the development of the main battle tank, and has seen use in a variety of roles including the support of light airborne or amphibious forces and reconnaissance. Modified IFVs are assuming these roles in many militaries due to their immediate availability, and as a cheaper alternative to developing and fielding a pure light tank.

In World War I industrial initiative also led to swift advances. The car industry, already used to vehicle mass production and having much more experience in vehicle layout, in 1916 designed the first practical light tanks, a class largely neglected by the British. It would be Renault's small tank design the FT, incorporating a proper climbing face for the tracks, that was the first tank to incorporate a top-mounted turret with a full rotation. In fact the FT was in many respects the first truly modern tank having a layout that has been followed by almost all designs ever since: driver at the front; main armament in a fully rotating turret on top; engine at the rear. Previous models had been "box tanks", with a single crowded space combining the role of engine room, fighting compartment, ammunition stock and driver's cabin. The FT would have the largest production run of any tank of the war - with over 3,700 built (most of those in 1918) it was more numerous than all British and German tanks combined.

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