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 1929 to 1932 that opened the night and clouded skies to flying. Only the Air Corps' assignment to deliver air mail in the first half of 1934, called "legalized murder" by Eddie Rickenbacker because of the 12 lives it claimed, detracted from the image that these aerial pioneers were helping to create.

Record-breaking military flights, alongside trailblazing civilian achievements by Charles Lindbergh and Amelia Earhart, represented the public side of a revolution in aviation technology. The staff at the Engineering Division, and later the Materiel Division, worked with American industry and the National Advisory Committee for Aeronautics (predecessor of the National Air and Space Administration) to develop essential technologies such as sodium-cooled engine valves, high octane gasoline, tetraethyl lead knock suppressants, stressed duraluminum aircraft structures, cantilevered wings, superchargers, turbosuperchargers, retractable landing gear, engine cowlings, radial engines, variable pitch constant speed propellers, and automatic pilots. The two-engine Keystone bomber of the 1920s, a biplane constructed of steel tubes and wires and fabric surfaces, with an open cockpit and fixed landing gear, could fly 98 miles per hour for 350 miles with one ton of bombs. A decade later Boeing's four-engine B-17 bomber could fly nearly 300 miles per hour for 800 miles with over two tons of bombs.

How would America's military aviators use this technology in war? The Army General Staff wanted to employ tactical air power "in

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