The Medium Mark A Whippet was a British tank of the First World War. It was intended to complement the slower British heavy tanks by using its relative mobility and speed in exploiting any break in the enemy lines. They arrived late in the war when the British Army was recovering from the offensives in Flanders. They first went into action in March 1918, and proved very useful to cover the fighting withdrawal of the infantry divisions recoiling from the German onslaught during the Spring Offensive.