Bell X-14 The Bell X-14 (Bell Type 68) was an experimental VTOL aircraft flown in the United States in the 1950s.
flying wing | Flying Wing, bomber, plane
F-107 - The military conducted a design competition for military aircraft in the 1950s. North American Aviation entered their F-107 fighter bomber. The plane made its first flight in 1956 and was retired in 1957. Only 3 of the planes were ever built. The plane was an evolutionary design of the F-100 Super Sabre Jet.
McDonnell XF-88B. “Designed for research into supersonic propeller design, it flew for the first time on 14 April 1953. Power was provided by two Westinghouse J34 turbojets and a nose-mounted Allison XT38 turboprop engine.” (via)