Sikorsky S-60 The helicopter accumulated 333 hours of flight in its two-year flight career, and was evaluated by the US Navy, with demonstrations also flown for the US Army. While effective in its designed role, the helicopter proved to be underpowered. Sikorsky was already working on an enlarged, turboshaft-powered successor, the Model S-64, which was ordered into production for the US Army as the Sikorsky CH-54 Tarhe. Igor Sikorsky was fully involved in the development of the prototype S-60, from the initial design through flight testing. It was one of the last aircraft to have this distinction. The prototype crashed in April
Igor Sikorsky No. 64 issued by the Imperial Aero Club of Russia in 1911. During a demonstration of the S-5, the engine quit and Sikorsky was forced to make a crash landing to avoid a wall. It was discovered that a mosquito in the gasoline had been drawn into the carburetor, starving the engine of fuel. The close call convinced Sikorsky of the need for an aircraft that could continue flying if it lost an engine. His next aircraft, the S-6 held three passengers and was selected as the winner of the Moscow aircraft exhibition held by the Russian Army in February