Westland Whirlwind (helicopter)

The Westland Whirlwind was a British helicopter built by Westland Aircraft under licence from the American Sikorsky S-55, which the United States flew as the H-19 Chickasaw. Westland bought the rights to manufacture and sell the S-55 in 1950, and converting the design to British standards took long enough that the first British-built prototype did not fly until August 1953. The Whirlwind served mainly with the Royal Navy's Fleet Air Arm in anti-submarine and search and rescue roles, and was also flown by the Royal Air Force and exported to other countries. It appeared in many variants, first with radial piston engines and later with the Bristol Siddeley Gnome turboshaft, and more than 400 were built, nearly 100 of them for foreign customers. The last Whirlwind left service in 1982. Its successor, the Westland Wessex, grew out of the same Sikorsky lineage.