Boeing YB-40 Flying Fortress March 1944. All of the aircraft were sent to reclamation, mostly at RFC Ontario in May 1945, being broken up and smelted. (A couple of the YB-40s can be seen in the 1946 movie "The Best Years of Our Lives", in the famous scene shot at the Ontario "graveyard".) No airframes were sold on the civil market. 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
B-17 Flying Fortress units of the United States Army Air Forces B-17 Flying Fortress units of the United States Army Air Forces This is a list of United States Army Air Forces B-17 Flying Fortress units of the United States Army Air Forces including variants and other historical information. Heavy bomber training organizations primarily under II Bomber Command in the United States and non-combat units are not included. The B-17 Flying Fortress was perhaps the most well-known American heavy bomber of the Second World War (1939/41-1945), . It achieved a fame far beyond that of its more-numerous contemporary, the Consolidated B-24 Liberator. The first pre-production Y1B-17 Fortress was delivered to the