Production. B-17F heavy bombers. Three-story jigs are used for the assembly of the inner wings of B-17F heavy bombers at the Long Beach, California plant of Douglas Aircraft Company. Better known as the "Flying Fortress," the B-17F is a later model of the 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. Douglas Aircraft Company