In 1950, the Fulton Airphibian became the first roadable aircraft, an aircraft designed to be used as a car or an airplane to be certificated by the Civil Aviation Administration (CAA). Other roadable aircraft had already been built, for example Waldo Waterman's Arrow/Aerobile and William Stout's Skycar, both of which are in the NASM collection--as well as other designs, but none won certification.