X-4, NASA history collection. Public domain image of NASA aircraft.

E-358In this 1950 straight-on view of the NACA High-Speed Flight Research Station's X-4 research aircraft, the horizontal tailless design is quite evident. The X-4 Bantam, a single-place, low swept-wing, semi-tailless aircraft, was designed and built by Northrop Aircraft, Inc. It had no horizontal tail surfaces and its mission was to obtain in-flight data on the stability and control of semi-tailless aircraft at high subsonic speeds. 1950 NASA Photo / NACA/NASA
NASA Identifier: 341531main_E-358