Boeing B-17 Flying Fortress Boeing B-17 Flying Fortress The Boeing B-17 Flying Fortress is a four-engined heavy bomber developed in the 1930s for the United States Army Air Corps (USAAC). Competing against Douglas and Martin for a contract to build 200 bombers, the Boeing entry (prototype Model 299/XB-17) outperformed both competitors and exceeded the air corps' performance specifications. Although Boeing lost the contract (to the Douglas B-18 Bolo) because the prototype crashed, the air corps ordered 13 more B-17s for further evaluation. From its introduction in 1938, the B-17 Flying Fortress evolved through numerous design advances, becoming the third-most produced bomber of all time,
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