Flying Fortress (Photographed in June 2006) The Flying Fortress, or Boeing B-17, is the most famous of US bombers from WWII. It was operated by a crew of 9, which included 2 pilots, a bombardier, a radio operator and 5 gunners. Although flown from a number of air fields around the world, it was most extensively operated by 8 Air Force from the UK against targets on the Continent. In service B-17s carried up to 13 machine guns and a maximum bomb load of 4,300 kilograms. Shown in the 2 photographs that follow is the only airworthy example of a B-17 in the UK. With a wing span of 31.7 meters and a length of 22.8 meters the B-17 could climb to a ceiling of 10,850 meters and cruise at 240 kilometers per hour. It was powered by four 1,200 horsepower Wright Cyclone R-1820-97 engines and had a top speed of 460 kilometers per hour. During the war B-17s were developed into 3 varients. The B-17C (Fortress I), B-17F (Fortress II) and B-17G (Fortress III). The first B-17 flew as a prototype on 28 July 1935 and entered service two years later in 1937.