It was W.G.K. Kilbourn, a Vickers engineer working for the DTD at the time, who transformed their idea into the reality of the prototype of the tank that would serve the British forces from the invasion of Normandy in June 1944 onwards. The first thing Kilbourn had to fix was the lack of a workable recoil system for the 17-pounder. The 17-pounder travelled back as it absorbed the recoil of the blast. This was too long for the Sherman's turret. Kilbourn solved this problem by redesigning the recoil system completely rather than modifying it. The recoil cylinders were shortened and placed on both sides of the gun to take advantage of the width of the turret.