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
U.S. Army airships Amongst the most interesting U.S. Army Airship Service experiments was to pursue the ability to operate airplanes from airships. While both the Germans and British had experimented with releasing fighters from rigid airships, it was the US Army which first flew an airplane from the ground and 'hooked' on to a trapeze suspended from an airship. Many tests involving a Sperry Messenger airplane and TC-3, a TC class blimp, were made in the mid-1920s. Eventually the technology was assumed by the US Navy on the "flying aircraft carriers", USS Akron (ZRS-4) and USS Macon (ZRS-5). The US Army continued to