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
RAF Bomber Command aircrew of World War II some air gunners were commissioned officers of which a small number were considerably older than most aircrew and even veterans of World War I. An Air Gunner wore a single-winged aircrew brevet with a wreath containing the letters AG on his tunic, above his left breast pocket denoting his trade specialization and very early in the war might also have the brass "winged bullet" qualification badge of a pre-war air gunner on his sleeve. Typically when flying operationally the following aircraft were crewed as below: Fairey Battle single-engined light bomber – most often used in daylight operations in a ground