The Westland WS-61 Sea King is a British license-built version of the American Sikorsky S-61 helicopter of the same name, built by Westland Helicopters now AgustaWestland. The aircraft differs considerably from the American version, with British-built Gnome engines, British made anti-submarine warfare systems and a fully computerised control system. The Westland Sea King was also produced as the Commando troop transport version for export.