Production. B-17F heavy bombers. Another new B-17F heavy bomber receives a final tuneup before its maiden flight from the Long Beach, California, plant of Douglas Aircraft. Better known as the "Flying Fortress," the B-17F is a later model B-17, which distinguished itself in action in the South Pacific, over Germany and elsewhere. It is a long range, high altitude, heavy bomber with a crew of seven to nine men and with armament sufficient to defend itself on daylight missions