When planning the amphibious invasion of Normandy, particular attention was paid to the composition of the bottom and behind the British landing beaches. After reconnaissance, an abundance of soft blue clay was found in which vehicles could get stuck.

The problem was assigned to the 79th Armored Division, commanded by General Percy Hobart, who developed equipment and vehicles for special situations. They were able to solve the problem quickly with a mat on a spool. This carpet layer became known as one of Hobart's Funnies.