In 1959, Sikorsky Aircraft began testing of a proof-of-concept heavy lift helicopter called the S-60. Initial tests proved successful and the U.S. Navy and Army showed interest in the concept. Sikorsky immediately began development of a more powerful version of the helicopter powered by two turbo-shaft engines. Designated the S-64 by Sikorsky and the H-54A by the U.S. Army, it made its first flight in May 1962. The U.S. Army named the helicopter Tarhe, but most people call them Skycranes. The CH-54 served through the last years of the Vietnam War and finally left military service in the early 1990s. Many surplus Skycranes have found new uses in civilian hands, being widely used for fighting forest fires and as heavy lift aircraft for erecting electrical towers, and in the timber industry.
273rd Aviation Company, Sanford Army Airfield, Long Binh, Vietnam, 1968
Pima Air & Space Museum