In 1941, Britain’s War Office asked BSA to develop a folding bicycle for airborne troops. The aim was to give soldiers transport after landing. Its distinctive curved frame tubes formed two connected halves: loosening two large thumbscrews allowed the front section to swing sideways alongside the rear.
British paratroopers used these bicycles during the Normandy landings and at Arnhem in 1944. A compact frame did not solve every transport problem, however. Dropping bicycles with a separate parachute could leave their wheels buckled on landing. Later, the folded bicycle was attached to the soldier and lowered before touchdown.
The BSA shows that folding bicycle history extends well beyond urban commuting. Here, delivery mattered more than saving space in a flat. Practical difficulties limited the idea’s success, but surviving examples reveal a specific engineering compromise: keeping a bicycle rideable while making it transportable.