Avro Canada VZ-9 Avrocar
This flying saucer was one of the world’s first successful vertical takeoff and landing (VTOL) aircraft. Developed as a secret U.S. military project in 1959, partly at the legendary Area 51 complex, the Avrocar was way ahead of its time. The propulsion system was intended to ride the Coandă effect and provide both lift and thrust from a single “turborotor.” This internal propeller sucked in air from underneath and blew out exhaust from the rim of the disk-shaped car/plane. Originally designed as a fighter-like aircraft capable of very high speeds and altitudes, the project was repeatedly scaled back over time and the U.S. Air Force eventually abandoned it. Development was then taken up by the U.S. Army for a tactical combat aircraft requirement, a sort of high-performance helicopter. During flight testing, the Avrocar proved to have serious unresolved thrust and stability problems that seriously degraded its performance; subsequently, the project was canceled in September 1961.