Sikorsky S-60 Sikorsky S-60 The Sikorsky S-60 helicopter, a prototype "flying crane", was derived from the S-56 in 1958. Proving to be underpowered, the development of the S-60 led to the larger, turbine-engined Sikorsky CH-54 Tarhe military transport helicopter, and its civil S-64 Skycrane variant, which were already on the drawing board by the time the sole example of the S-60 crashed on 3 April 1961. In 1958, Sikorsky began designing the S-60 as a prototype "flying crane" helicopter. The S-60 utilized the transmission, rotor system and piston engines from the CH-37/S-56. The fuselage of the S-60 was a simple "pod-and-boom" design
Sikorsky S-9 completion the S-9 was found to be substantially heavier than anticipated and the engine only delivered 80% of its rated horsepower. Initial flight tests revealed very poor performance. The engine was replaced by a Gnome Monosoupape and further flights showed only a nominal increase in speed. The machine was eventually scrapped. Sikorsky S-9 The Sikorsky S-9 "Kruglyj" (Rounded One) was a Russian single engine prototype aircraft completed in the spring of 1913 by the Russian Baltic Railroad Car Works while Igor Sikorsky was the chief engineer of the aircraft manufacturing division. The S-9 was a three-seat mid-wing monoplane with constant-chord