Journal OACI

No. 2

Full-scale modal of a tilt-fan vertical / short take-off and landing (V/STOL) aircraft design is shown undergoing proof-of-principle testing in the Ames Research Center wind tunnel in California. Powered by two General Electric TF-34 high-bypass-ratio engines, aircraft vertical lift-off is achieved by rotating the turbofans to the vertical position. Control is achieved during this phase through use of computer-controlled moveable aerodynamic surfaces (vanes) immersed in the exhaust of the engines. Strakes, or longitudinal fences, are employed on the fuselage undersurface to make maximum use of ground effect and also to prevent the upwash of hot exhaust from being reingested by the engines, thus maintaining maximum thrust.