Sikorsky X-Wing
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Wikipedia:Translation/Sikorsky X-Wing
The Sikorsky X-Wing was an experimental hybrid helicopter/fixed-wing aircraft developed between 1983 and 1988 by helicopter manufacuter Sikorsky with NASA and DARPA funding.
Intended to take off vertically like a helicopter, the craft's rigid rotors could be stopped in mid-flight to act as X-shaped wings to provide additional lift during forward flight, as well as having more conventional wings.
Instead of controlling lift by twisting its blades as more conventional helicopters do, the craft used compressed air fed from the engines and expelled from its blades to generate a virtual wing surface, similar to blown flaps on a conventional platform. Computerized valves made sure the compressed air came from the correct edge of the rotor, the correct edge changing as the rotor rotated. This approach appears to have been abandoned for the tiltrotor configuration employed by the V-22 Osprey.
The X-Wing may have been named after the fictional X-Wing starfighter from the Star Wars movies (with the first movie premiered in 1977), but is more likely named that because of its 4 bladed rotors' ability to double as a x-shaped wing.