 The Westland WS @-@ 61 Sea King is a British licence @-@ built version of the American Sikorsky S @-@ 61 helicopter of the same name , built by Westland Helicopters . The aircraft differs considerably from the American version , with Rolls @-@ Royce Gnome engines ( derived from the US General Electric <unk> ) , British @-@ made anti @-@ submarine warfare systems and a fully computerised flight control system . The Sea King was primarily designed for performing anti @-@ submarine warfare ( ASW ) missions . A Sea King variant was adapted by Westland as troop transport known as the Commando . 
