AIR PILOTS IN THE MAKING. 
Photo shows American flying cadets learning "Bird's-eye-map reading" in British school.
Air Service, United States Army photograph
National Archives of the United States via Gorrell's History of the American Expeditionary Forces Air Service, 1917-1919, Series B, Air Service Activities with the French, British, and Italians, Volume 2, History of the Air Service in Great Britain