Boeing B-17 Flying Fortress

The Boeing B-17 Flying Fortress was an American heavy bomber used by the US Army Air Corps during World War II. This iconic military aircraft was the first long-range bomber employed by the United States in this armed conflict to attack enemy industrial plants, bridges, and communication centers both in Germany and Japan. The fact that it bristled with machine gun emplacements led to it being called by the press 'Flying Fortress'. The B-17 had first been conceived as a coastal patrol aircraft to guard and protect America's coastlines. However, this large airplane would soon be developed into a crucial offensive weapon to carry out systematic air raids over Germany and Japanese-held islands in the Pacific.

The Boeing B-17 Flying Fortress had been designed to meet an US Army Air Corps requirement for a long-range aircraft, capable of flying at 400 km/h (250 mph). The prototype, Model 299, was taken aloft for the first time on July 28, 1935, by the company pilot Leslie Tower. This big aircraft handled quite well in its first flight, but problems were experienced with the tail wheel; it shimmied (wobbled) slightly. However, it would soon be fixed as well as other technical faults. After three years of flight tests, the Flying Fortress was finally introduced into service with the US Army Air Corps on April 25, 1938, as the B-17B version. By the end of the war, more than 12,000 Flying Fortress bombers had been produced.

The bomber that was to become legendary first saw combat action not with the US Air Corps but with the British Royal Air Force, when, as part of the 90th Squadron of 2 Group, carried out high-altitude, daylight raids against German 'fringe' targets in northern Europe in July 1941. On August 10, 1942, the UK-based US 8th Air Force began its bombing campaign against the Third Reich, using the B-17E variant of the aircraft. However, this version would soon be replaced by the B-17F, which was clearly superior to its predecessor as this new model had incorporated 400 design changes, which included a new power plant, with more powerful Wright Cyclone engines, self-sealing oil tanks, and additional fuel capacity for longer range. By October 1943, the B-17F had partially been supplanted in the first line service by the even better B-17G version, which was fitted with a twin 12.7-mm (.50-cal) Bendix chin turret mounted under nose of aircraft to counter the German fighters head-on attacks.

Technical Description

The Boeing B-17 Flying Fortress was a large four-engine monoplane of all-metal construction. It had monocoque, riveted aluminum fuselage. The aircraft featured cantilever low-wing, with large and strong root. Both the leading and trailing edge of wing tapered towards the tip. Aside from the ailerons, the wing trailing edge was fitted with wide flaps for better handling and control of the aircraft. The aircraft tail assembly was of the conventional type, with a large rudder on the vertical fin. It had retractable landing gear, with the main wheels retracting into engine nacelles. The B-17G was powered by four Wright R-1820-97 Cyclone turbo-supercharged radial piston engines, each one being able to put out 1,200 horsepower.

Specifications (B-17G)

Type: heavy bomber and patrol aircraft.

Length: 22.66 m (74 feet, 4 inches)

Wing Span: 31.62 m (103 feet, 9 inches)

Wing Area: 131.92 m2 (1,420 square feet)

Height: 5.82 m (19 feet, 1 inch)

Power Plant: four 1,200-HP, Wright R-1820-97 Cyclone radial piston engines.

Maximum Speed: 462 km/h (287 mph)

Range: 3,219 km (2,000 miles)

Rate of Climb: 4.6 m/s

Service Ceiling: 10,850 m (35,600 feet)

Crew: 10

Armament: thirteen 12.7-mm (.50-cal) M2 Browning machine guns mounted in chin turret, in nose, on Sperry underbelly turret, and upper Sperry turret; 3,600-kg (8,000-lb) of bombs.