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Canceled American military plane project of the 1940s-1950s
The Republic Aviation AP-100 was a project for a VTOL, six-turbojet engined, nuclear capable, strike fighter concept. It had three ducted fans in the centre of its fuselage and tail and was a possible contender for the TFX Program. The project was designated as a "fighter", but in fact was a tactical attack aircraft capable of delivering a small nuclear bomb. The weight of the aircraft would have been 38,000 lb (17,237 kg) with its engines generating 14,400 lb (6,532 kg) of thrust.
Project Hummingbird (Technical Report) A Technical Summary and Compilation of Characteristics and Specifications on Steep-Gradient Aircraft, Volume 88, April 1961. By United States Federal Aviation Agency. Page 143-144, Figure 175.
Air Progress History of Aviation Spring 1961 edition
Aviation Week and Space Technology, Lift-Fan Tests Show VTOL Potential. August 8, 1960