The CH-53 Sea Stallion (aka S-65) family of helicopters used for heavy-lift missions. It is made by the Sikorsky helicopter company of America. The S-65 first took flight in 1964 in the form of the YCH-53 prototype. The initial project started in 1960 when the US marine corps began asking for a replacement for the current generation of piston-powered helicopters in heavy lift roles. It was in 1962, after messing around with tiltrotor designs for two years, that the USMC issued a request for a heavy lift helicopter. Various proposals from several manufacturers were submitted. In the case of the Sikorsky what was proposed amounted to a scaled up version of the existing S-61R. Competition was intense, but in the end Sikorsky beat the likes of Boeing Vertol and Kaman Aircraft. Side-by-side the S-65 and S-61R “Jolly Green Giant” have quite a few similarities. Which is understandable given that the S-65 derives from it. Although the fuselage is watertight, it was not explicitly designed for amphibious use. The flight controls consist of a mechanical system backed up by no fewer than three independent hydraulic systems. Unlike civilian craft the Sea Stallion is armor plated to protect the crew, of which there are four. It can carry a load of 38 troops, an 8000 pound internal load or a 13 000 pound external load. All of this is made possible by two GE T64-6 turboshaft engines with 2850 shaft horsepower each. These drive a six-blade main rotor. The “D” variant increases the engine power to 3925 shaft horse power per engine by making use of the GE T64-413 engines.
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