Question Mark (aircraft) Question Mark (aircraft) Question Mark (""?"") was a modified Atlantic-Fokker C-2A transport airplane of the United States Army Air Corps. In 1929, commanded by Major Carl A. Spaatz, it was flown for a flight endurance record as part of an experiment with aerial refueling. "Question Mark" established new world records in aviation for sustained flight (heavier-than-air), refueled flight, sustained flight (lighter-than-air), and distance between January 1 and January 7, 1929, in a non-stop flight of more than 150 hours near Los Angeles, California. Following the record-setting demonstration, the C-2A was returned to transport duties. In 1931 more powerful engines replaced
Harlan Gurney had attended the US Army Air Corps flight school at Brooks Field with Lindbergh. In 1927, when Lindbergh took leave from Robertson Aircraft to make his epic non-stop New York to Paris flight, Gurney replaced him as Robertson’s chief air mail pilot and flight instructor. Robertson was soon absorbed by Universal Air Lines for which Gurney became director of operations. In 1929 he was lured to Transcontinental Air Transport (TAT) for which Lindbergh was technical advisor. TAT, which was known as 'The Lindbergh Line,' offered coast to coast transportation in 36 to 48 hours hours using a combination of linked