The Westland Wessex is a British-built turbine-powered development of the Sikorsky H-34. It was developed and produced under licence by Westland Aircraft. One of the main changes from Sikorsky's H-34 was the replacement of the piston-engine powerplant with a turboshaft engine. Early models were powered by a single Napier Gazelle engine, while later builds used a pair of de Havilland Gnome engines.
Westland Wessex
Cockpit
A pair of Royal Navy Wessex helicopters on the flight deck of HMS Intrepid, 1968
Troops embarking on a Westland Wessex during a training exercise
The Sikorsky H-34 "Choctaw" is an American piston-engined military helicopter originally designed by Sikorsky as an anti-submarine warfare (ASW) aircraft for the United States Navy. It has seen extended use when adapted to turbine power by the British licensee as the Westland Wessex and Sikorsky as the later S-58T.
Sikorsky H-34
A U.S. Navy HSS-1 with dipping sonar deployed, in 1960.
CH-37C and UH-34D of the United States Marine Corps.
A U.S. Coast Guard HUS-1G in 1960.