The Navion was designed by North American Aviation in the 1940’s. First designated the NA-143, it was later produced as the NA-145 for the civilian market that was expected to boom during the post war years. Two prototypes and 1,027 were produced. The design attracted the interest of the United States Air Forces who ordered 83 copies of the militarized NA-154 version, designated the L-17A, to be used as a liaison aircraft, personnel and cargo carrier, and pilot trainer. In 1948 Ryan Aeronautical Company acquired the design from North American Aviation.