The Insane Engineering of the B-17 Flying Fortress

Video from the channel Ingenieurwesen Dokumentation about Boeing B-17 Flying Fortress, linked on its Above Ten Thousand entry. Duration: 45:43. Language: German. Video type: Documentary.

A German-language documentary that reviews the technical solutions of the Boeing B-17 Flying Fortress: its four-engine layout, the evolution of its defensive armament, mass production, flight controls, powerplant, structural strength, crew support systems, and the test program. It opens with the anecdote of an aircraft that returned to base after losing a roughly 20-foot wing section.

The narrator traces the aircraft's origin to the Army Air Corps specification of 1934, when twin-engine bombers were the norm. It then goes through the variants: the B-17E lengthened the fuselage by about 10 feet and enlarged the tail; the B-17F introduced an almost frameless glazed nose for the bombardier, and the B-17G added the Bendix chin turret against head-on attacks. It also explains the "combat box" formation, in which the crossfire of several bombers protected each other, and the joint production by Boeing, Douglas and Vega, a Lockheed subsidiary.

According to the video, the R-1820 Cyclone engines went from 920 to 1,200 hp and carried General Electric turbochargers for high-altitude operation. Armament grew from four to thirteen .50-caliber machine guns, with a spherical Sperry ball turret underneath. 12,731 units were built, and by March 1944 production reached a rate of 362 per month. The controls were mechanical, via redundant cables, and hydraulics were limited to the cowl flaps and brakes, which reduced vulnerability in combat; the Norden bombsight could guide the aircraft through the C-1 autopilot. The documentary also describes the oxygen system with 18 G-1 bottles, the heated suits, and the wind-tunnel tests in Seattle, and credits the B-17 with dropping more than 640,000 tons of bombs, 42.6% of the total dropped on Nazi Germany and the occupied territories.