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
Airplane designed to be remotely or computer-controlled. The Wright brothers invented and flew the first airplane in 1903, recognized as "the first sustained and controlled heavier-than-air powered flight". They built on the works of George Cayley dating from 1799, when he set forth the concept of the modern airplane (and later built and flew models and successful passenger-carrying gliders). Between 1867 and 1896, the German pioneer of human aviation Otto Lilienthal also studied heavier-than-air flight. Following its limited use in World War I, aircraft technology continued to develop. Airplanes had a presence in all the major battles of World War II.