Sikorsky CH-53 Sea Stallion Sikorsky CH-53 Sea Stallion The CH-53 Sea Stallion is the most common name for the Sikorsky S-65 family of heavy-lift transport helicopters. Originally developed for use by the United States Marine Corps, it is in service with Germany, Iran, Israel, and Mexico. The United States Air Force operated the HH-53 "Super Jolly Green Giant" during the late– and post–Vietnam-War era, updating most of them as the MH-53 Pave Low. The dimensionally-similar CH-53E Super Stallion is a heavier-lifting, improved version designated S-80E by Sikorsky. Its third engine makes it more powerful than the Sea Stallion, which it has replaced in the
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