Aerial refueling craft was eventually modified by Airspeed to Cobham's specification, for a non-stop flight from London to India, using in-flight refueling to extend the plane's flight duration. Meanwhile, in 1929, a group of U.S. Army Air Corps fliers, led by then Major Carl Spaatz, set an endurance record of over 150 hours with the "Question Mark" over Los Angeles. Between June 11 and July 4, 1930, the brothers John, Kenneth, Albert, and Walter Hunter set a new record of 553 hours 40 minutes over Chicago using two Stinson SM-1 Detroiters as refueler and receiver. Aerial refueling remained a very dangerous process
Monument of Sivrihisar Airplane forces on 12 August 1921. The town later was recaptured on 20 September 1921 during the Battle of Sakarya. During the war, Turkish army had only five warplanes, which were old and not maintained. The military badly needed a new airplane. After the Turkish control was reestablished, the citizens of Sivrihisar decided to buy a new airplane to show their gratitude to the army and after a fund drive they collected TL 4,000. With this money, they bought a single-engine two-seat biplane bomber aircraft of type Breguet 14 B.2 from Breguet Aviation in France. The plane was named after the