B-17 Flying Fortress units of the United States Army Air Forces 2d Bombardment Group, Langley Field, Virginia on 11 January 1936; the first production B-17B was delivered on 29 March 1939 also to the 2nd Bombardment Group. A total of 12,677 production Fortresses was built before production came to an end. In August 1944, the Boeing B-17 equipped no less than 33 overseas combat groups. The last Boeing-built B-17G was delivered to the USAAF on 13 April 1945. Following the end of World War II, the Flying Fortress was rapidly withdrawn from USAAF service, being replaced by the B-29 Superfortress. Literally thousands of Fortresses used in combat in Europe by Eighth
B-17 Flying Fortress units of the United States Army Air Forces the most experienced B-17 units, and their departure from England slowed down the development of the Eighth Air Force’s offensive. Later, two newly trained II Bomber Command groups (2d, 99th) deployed from the United States. The four B-17E groups formed the heavy bomber component of XII Bomber Command (and Northwest African Strategic Air Force). In North Africa Flying Fortresses were used against German and Italian military targets in Algeria and Tunisia, and to attack German shipping in the Mediterranean. Flying Fortresses took part in the bombardment of the Italian stronghold of Pantelleria, the invasion of Sicily and the invasion of