4 Airworthiness Directives: 3 airplane, 1 rotorcraft.
AD 51-19-04 · published 1951
Martin-Marietta Corporation Airplanes
AD 51-20-01 · published 1951
Airlift International, Inc., Curtiss-Wright Corporation, Flying Tiger Line, Inc., L. B. Smith Aircraft Corporation, Skyways International Trading and Transport Co., Tempo Design Corporation Airplanes
AD 51-20-02 · published 1951
Martin-Marietta Corporation Airplanes