Boeing YB-40 Flying Fortress Boeing YB-40 Flying Fortress The Boeing YB-40 Flying Fortress was a modification for operational testing purposes of the B-17 Flying Fortress bomber aircraft, converted to act as a heavily armed gunship for other bombers during World War II. At the time of its development, long-range fighter aircraft such as the North American P-51 Mustang were just entering quantity production, and thus were not yet available to accompany bombers all the way from England to Germany and back. Work on the prototype, Project V-139, began in September 1942 by converting the second production B-17F-1-BO (serial number 41-24341) built. Conversion work was
81st Flying Training Wing (World War II) 81st Flying Training Wing (World War II) The 81st Flying Training Wing is an inactive United States Air Force unit. It was last assigned to the Western Flying Training Command, and was disbanded on 1 November 1945 at the Santa Ana Army Air Base, California. The squadron was a World War II Command and Control unit, its mission was to provide classification and preflight testing of aviation cadets. It was one of three such centers, the others being at Maxwell Field, Alabama and San Antonio Aviation Cadet Center, Texas. There is no lineage between the current United States Air Force