Tanks in World War I
The continued need for four men to drive the tank was solved with the Mark V which used Wilson's epicyclic gearing in 1918. Also in 1918 the French produced the Renault FT, the result of a co-operation between Estienne and Louis Renault. As mentioned before, it had the innovative turret position, and was operated by two men. At just 8 tons it was half the weight of the Medium A "Whippet" but the version with the cannon had more firepower. It was conceived for mass production, and the FT became the most produced tank of World War I by a wide margin, with over 3,000 delivered to the French Army. Large numbers were used by the Americans and several were also lent to the British.
History of the tank
The German response to the Cambrai assault was to develop its own armoured program. Soon the massive A7V appeared. The A7V was a clumsy monster, weighing 30 tons and with a crew of eighteen. By the end of the war, only twenty had been built. Although other tanks were on the drawing board, material shortages limited the German tank corps to these A7Vs and about 36 captured Mark IVs. The A7V would be involved in the first tank "vs". tank battle of the war on April 24, 1918 at the Second Battle of Villers-Bretonneux—a battle in which there was no clear winner.
Numerous mechanical failures and the inability of the British and French to mount any sustained drives in the early tank actions cast doubt on their usefulness—and by 1918, tanks were extremely vulnerable unless accompanied by infantry and ground-attack aircraft, both of which worked to locate and suppress anti-tank defences.