Flight Training at North Island (Later Rockwell Field), San Diego, California in December 1917.    Upper left photo shows Major Hugh Knerr in the cockpit of a Curtiss JN-4 Jenny upon his arrival at the airfield
United States Army
Cameron, Rebecca Hancock, 1999, Training to Fly. Military Flight Training 1907-1945 Air Force History and Museums Program, Air Force Historical Research Agency, Maxwell AFB, Alabama