The Sikorsky SH-3 Sea King is an American twin-engine anti-submarine warfare (ASW) helicopter designed and built by Sikorsky Aircraft. A landmark design, it was one of the first ASW rotorcraft to use turboshaft engines. The Sea King has its origins in efforts by the United States Navy to counter the growing threat of Soviet submarines during the 1950s. Accordingly, the helicopter was specifically developed to deliver a capable ASW platform.