High Quality Content by WIKIPEDIA articles! The Sikorsky SH-3 Sea King (company designation S-61) is a twin-engined anti-submarine warfare (ASW) helicopter. It served with the United States Navy and other forces, and continues to serve in many countries around the world. The Sea King has been built under license in Italy and Japan, and in the United Kingdom as the Westland Sea King. The major civil versions are the S-61L and S-61N.