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US Army Sikorsky CH-54 Tarhe heavy lift cargo helicopter

initial work on the Sikorsky “sky-crane” helicopters began in 1958 with the piston-engined Sikorsky S-60. The first flight of the turboshaft-powered S-64 Skycrane was on 9 May 1962.[2]

The United States Army eventually purchased 105, designating them CH-54. Used in Vietnam for transport and downed-aircraft retrieval, it was highly successful. As of 2014, it holds the helicopter record for highest altitude in level flight at 11,000 m (36,000 ft), set in 1971,[3] and fastest climb to 3,000,[4] 6,000,[5] and 9,000[6] m (10,000, 20,000, and 30,000 ft).

The Skycrane can hold its cargo up and tight against its center spine to lessen drag and eliminate the pendulum effect when flying forward, as well as winch vehicles up and down from a hovering position, so the helicopter can deploy loads while hovering. Due to budget cuts, the Heavy Lift Helicopter (HLH) program was canceled and the CH-54 was not upgraded with larger engines. The Boeing CH-47 Chinook gradually supplemented it in combat and eventually replaced it in Regular Army aviation units, although CH-54 Skycranes remained in Army National Guard service until 1991.