L-749 Constellation / TWALockheed L 749 TWA Constellation. Design of the Lockheed L 749 began in 1939 to meet the requirement of Pan American Airways and Transcontinental &, Western Air (now Trans World Airlines), for a 40 passenger airliner for use on domestic routes. Manufacture of the airplane was initiated, but with the outbreak of World War II aircraft on the production line were commandeered for service with the USAAF as transports under the designation C 69, the first