B-17 Flying Fortress

B-17 Flying Fortress
Name	B-17 Flying Fortress
Caption	A B-17F in flight.
Type	Heavy bomber
National origin	United States
Manufacturer	Boeing
Designer	E. Gifford Emery, Edward Curtis Wells
First flight	28 July 1935
Introduction	April 1938
Retired	1968 (Brazilian Air Force)
Status	Retired
Primary user	United States Army Air Forces
Number built	12,731
Unit cost	$238,329 (1945)

B-17 Flying Fortress was a four-engined heavy bomber developed in the 1930s for the United States Army Air Corps (USAAC). Renowned for its durability and defensive firepower, it became a symbol of the American air power during World War II, primarily employed in the daylight strategic bombing campaigns against German industrial and military targets. Though it suffered high losses, its ability to absorb damage and return home cemented its legendary status.

Development and design

The aircraft originated from a 1934 United States Army Air Corps specification for a multi-engine coastal defense bomber. The Boeing design team, led by E. Gifford Emery and Edward Curtis Wells, created the Model 299, which first flew in 1935. After an initial crash, the United States Army Air Corps ordered 13 YB-17 service test aircraft for further evaluation. Its defining feature was an extensive suite of .50 caliber machine guns in multiple powered turrets, earning it the "Flying Fortress" name from a Seattle Times reporter. Key design elements included a large Bomb bay, a robust Semi-monocoque fuselage, and four Wright R-1820 radial engines, which were later upgraded to more powerful variants from Pratt & Whitney.

Operational history

The B-17 first saw combat with the Royal Air Force in 1941, but its major service was with the United States Army Air Forces (USAAF) in the European Theater of Operations. As the backbone of the Eighth Air Force's bombing offensive, it participated in pivotal raids such as those on Schweinfurt and Regensburg, which aimed to cripple the German aircraft industry. The introduction of the P-51 Mustang as a Long-range escort fighter in late 1943 dramatically reduced losses. The B-17 also served in the Pacific Theater with the Fifth Air Force and Twentieth Air Force, though in smaller numbers than the B-29 Superfortress. Notable missions included the Doolittle Raid planning and the Battle of the Bismarck Sea.

Variants

The initial production model was the B-17B, featuring a larger rudder and redesigned nose. The B-17C and B-17D incorporated improved armor and self-sealing fuel tanks. The definitive B-17E introduced a vastly redesigned airframe with a distinctive Tail gunner position and a Bendix turret. The B-17F, built by Boeing, Douglas Aircraft Company, and Lockheed Vega, had a frameless Plexiglas nose. The final and most-produced variant was the B-17G, which added a Bendix "chin" turret to counter Head-on attacks from Luftwaffe fighters like the Focke-Wulf Fw 190. Specialized variants included the XB-40 escort gunship and the F-9 photographic reconnaissance aircraft used by the USAAF.

Operators

The primary operator was the United States Army Air Forces, with thousands serving in its various air forces. The Royal Air Force operated several hundred, designated Fortress I through III, with No. 90 Squadron RAF being an early user. Post-war, many were transferred to other air forces under the Military assistance program, including the French Air Force, Israeli Air Force, and Dominican Air Force. The Brazilian Air Force was the last military operator, retiring its aircraft in 1968. A small number were also used by the United States Navy and United States Coast Guard for Air-sea rescue and Anti-submarine warfare duties, designated as PB-1s.

Specifications (B-17G)

* **Crew:** 10 (Pilot, Co-pilot, Bombardier, Navigator, Radio operator, Flight engineer, Ball turret gunner, Tail gunner, two Waist gunners) * **Length:** 74 ft 4 in (22.66 m) * **Wingspan:** 103 ft 9 in (31.62 m) * **Height:** 19 ft 1 in (5.82 m) * **Empty weight:** 36,135 lb (16,391 kg) * **Powerplant:** 4 × Wright R-1820-97 "Cyclone" turbo-supercharged radial engines * **Maximum speed:** 287 mph (462 km/h) * **Combat range:** 2,000 mi (3,200 km) * **Service ceiling:** 35,600 ft (10,850 m) * **Armament:** 13 × .50 in Browning M2 machine guns; up to 9,600 lb (4,350 kg) of Bombs

Cultural impact

The B-17 remains an enduring icon of World War II, heavily featured in films like Twelve O'Clock High and Memphis Belle. Its crews, celebrated for their courage in the face of formidable Luftwaffe defenses and Flak over targets like Berlin, were immortalized in books such as Catch-22. The aircraft is a centerpiece of museums worldwide, including the National Museum of the United States Air Force and the Imperial War Museum Duxford. Several dozen are kept airworthy by organizations like the Collings Foundation, serving as flying memorials. Its image is synonymous with the Mighty Eighth and the Combined Bomber Offensive, shaping public perception of the Air war for generations.

Category:Boeing aircraft Category:World War II bombers of the United States Category:Four-engined aircraft