Sikorsky HH-52 Seaguard

The Sikorsky HH-52 Seaguard, company designation S-62, is an early amphibious helicopter designed and built by Sikorsky Aircraft. It was the company first amphibious rotorcraft to fly and the US Coast Guard first turbine-powered and first amphibious helicopter. Sikorsky developed it as a commercial venture in the late 1950s, combining the dynamic components of the S-55 with a boat-hull fuselage and a single lightweight turboshaft engine. The prototype flew in May 1958 with a General Electric T58 engine, and the first of 99 production helicopters was delivered to the Coast Guard on 9 January 1963.