In 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.