The Sikorsky H-34 Choctaw (Company designation S-58) was a military helicopter originally designed by American aircraft manufacturer Sikorsky for the United States Navy for service in the anti-submarine warfare (ASW) role.
Sikorsky H-34s have since served mostly as medium transports on every continent with the armed forces of twenty-five countries - from combat in Algeria, the Dominican Republic, Nicaragua, and throughout Southeast Asia, to saving flood victims, recovering astronauts, fighting fires, and carrying presidents. As one of the last piston-powered helicopter designs before its replacement by turbine-powered types such as the UH-1 Huey and CH-46 Sea Knight, it would see a remarkably long run of 2,108 H-34s produced between 1953 and 1970. It would see extended use when adapted to turbine power as the Westland Wessex and the later S-58T. The British did not retire the Wessex until 2003 as the main transport helicopter; it was replaced by the Aérospatiale Puma.