Christie 1921 Tank

In the Great War, America found itself with a muscular heavy equipment manufacturing industry that could have readily produced tanks; but it had no tank designs. The US ended up building licensed copies of the French FT-17 light tank, and the Mark VIII “International” heavy tank as the war ended. After the war, the US began experimenting with tank designs of its own. Walter Christie was a talented and experienced automotive engineer. He submitted designs and working prototypes of tanks to the US Army throughout the interwar period. In WW1, tanks were viewed as an armored, self-propelled siege-engines for breaking through the trench lines at which point their job was done. They were slow, the speed of a walking infantryman, and mechanically unreliable. Christie’s 1921 prototype had a two-man crew, was small, turretless, armed with a 57mm gun and two .30 caliber machine guns. It was fast – 13 mph (20.9 km/h). Christie solved the problem of getting slow, unreliable tanks to the battlefield by removing the tracks, storing them on the fenders, and running on the road wheels over improved roads. The downside of the Christie suspension design was its very rough ride. The US Army Ordnance Department requested that Christie improve the suspension system. Although only a single prototype was built, it laid the groundwork for future high-speed tanks.