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B-17 Flying Fortresses

Boeing Flying Fortresses over Seattle.


The painting shows the 303rd Bomb Group B-17G Bonnie-B taxiing out of its hardstand area onto the Molesworth, England, base's East-West runway for "slow timing"—running in a newly replaced engine.

B-17 production

Boeing aircraft plant, Seattle, Washington. Production of B-17 (Flying Fortress) bombing planes. Pouring a lead die to be used in the production of parts.

B-29 Superfortress

B-29 Superfortress.

Boeing 314 clipper

Boeing 314 Clipper.

Boeing Military Aircraft in the 1930s and 1940s

In 1934, the U.S. Congress passed legislation that forced aircraft manufacturers to separate from airline companies. The giant holding companies that had formed during the 1920s were dissolved. For the aircraft company Boeing, this meant that it became an independent company, no longer part of the United Aircraft and Transport Corporation (UATC) that had included United Air Lines, Pratt & Whitney, Sikorsky, and several other companies. Only Stearman Aircraft, which built some 8,500 Kaydet training biplanes between 1936 and 1944, remained. Bill Boeing decided to retire from the company chairmanship, and Phil Johnson, who had been company president, resigned. Claire Egtvedt, who had become president of the Boeing Airplane Company in 1933, took over the company's reins.

Boeing began its independent existence with only about $500,000 in cash and hardly any business. In August 1934, 1,700 employees were laid off, leaving only 700 workers. Egtvedt decided that the company's future lay in large passenger airplanes and in bombers.

The country's first true heavy bomber was the XB-15 that Boeing developed in response to a small 1934 Air Corps contract. It was larger than anything that had been built before, with a 149-foot (45-meter) wingspan and weighing 37,709 pounds (17,105 kilograms) empty. A one-of-a-kind aircraft, it proved that a large bomber was practical.

While the XB-15 was still being developed, Boeing received an Army contract for a sample multiengine bomber that was supposed to lead to an order for at least 20 aircraft. Although it was quickly running out of money, the company decided to take the risk of producing this four-engine plane, called the Model 299. Borrowing some features from the still unbuilt XB-15, Boeing designers came up with a low-wing monoplane, the B-17, that, when unveiled only 12 months later, was so large that a reporter dubbed it a "flying fortress." With later modifications this aircraft became legendary, and the more than 10,000 built served in every theater of World War II and in Europe it became the mainstay of the strategic bombing campaign against Germany.

Tragically, the plane crashed on its first flight test in 1935 because a lock had not been released before takeoff, killing three of the four crewmembers. The Army awarded a competitor, Douglas Aircraft, a contract for its B-18 instead even though the plane was slower and had been surpassed in all categories by the B-17 in its flight tests. Boeing did manage to eke out a small contract for 13 B-17s, and its performance with the Army's Second Bombardment Group won praise. Government orders then began trickling in, and models equipped with the Norden bombsight for precision bombing were delivered in 1939 and 1940. By the 1940s, Boeing was building the plane at a rapidly increasing rate. To disguise its production facility during World War II, the company built burlap houses and chicken-wire lawns on its roof, so from the air, it looked like a suburban neighborhood. Although the plane had a number of faults, and it was necessary to add more armaments to every model, it remained in production through World War II and served in every theatre. When production ended, Boeing had built a total of 6,981 B-17s, with Douglas and Lockheed building another 5,745.

The B-29 Superfortress was the second Boeing plane to become famous during the war. The plane received the strong endorsement of General Hap Arnold, who was convinced that the United States badly needed an airplane that was larger, faster, and which could travel farther without refueling than the B-17.

Plans for such a plane were drawn up in 1939. So when Poland was overrun in September, Boeing was ready with its design while General Arnold worked on getting authorization from the War Department. Larger than the B-17, the B-29 fuselage was divided into three pressurized compartments, and the plane had a crawl tube that went from the cockpit to the tail. Its wing was extraordinarily strong, able to support nearly twice the weight per square foot of wing area as the B-17. It also used a welding method adopted from the German Heinkel 111 bomber that reduced its weight and made assembly easier.

Boeing began producing the B-29 bomber in 1942, and there were many problems. Its flight-testing was also marred by a tragic accident. In February 1943, during a test piloted by the skilled Eddie Allen, the new 2,200-horsepower (1,641-kilowatt) Wright R-3350 engine caught fire, then the wing. The flames spread, and the plane fell onto the roof of the Frye meatpacking plant in Seattle, setting the building on fire. All 11 aboard died, as did 19 Frye employees and five firemen. Modifications were made, and the first Superfortress rolled out in September 1943. It flew its first mission on June 5, 1944. Altogether, 3,970 B-29s were built before production ended in 1946, and Boeing had produced 2,766 of them. The B-29 was used primarily to bomb large areas in Japan. On August 6, 1945, a B-29, the Enola Gay, dropped the world's first atomic bomb on Hiroshima. Three days dater, another B-29, the Bocks Car, dropped another bomb on Nagasaki. Japan surrendered soon after.

Meanwhile, Boeing was also producing a small number of commercial airplanes. In the mid-1930s, Pan American Airlines had asked for a long-range, four-engine flying boat for its trans-oceanic routes. Boeing developed the Model 314, nicknamed the Clipper after the oceangoing sailing vessels of an earlier time. The plane drew on the wing design of the XB-15 and added powerful new Wright 1,500-horsepower (1,119-kilowatt) engines. Its first transatlantic flight was on June 28, 1939, and by the end of the year, the luxurious Clipper was making routine flights across the Pacific Ocean. Boeing built 12 Model 314s between 1939 and 1941. During the war, the plane ferried troops and supplies across the ocean, and a Clipper carried President Franklin D. Roosevelt to his meeting with Winston Churchill at Casablanca in 1943.

In 1940, Boeing built the first high-altitude commercial transport and the first four-engine airliner in scheduled service within the United States, the Model 307 Stratoliner. Used by Pan American Airways and Trans World Airlines, its pressurized cabin allowed it to fly above the weather, and its wide fuselage had space for sleeping berths. Multimillionaire Howard Hughes bought one and converted it into a flying penthouse. The Stratoliner was the first plane to have a flight engineer as a crewmember. In 1942, the 10 Stratoliners that had built were stripped of their luxurious décor and drafted into service by the Army as C-75 military transports. With the end of Stratoliner production, commercial production was halted until the war's end.

—Judy Rumerman


Bowman, Martin, compiler. Boeing: Images of America. Stroud, Gloucestershire, England: Tempus Publishing, Ltd., 1998.

Serling, Robert J. Legend and Legacy The Story of Boeing and Its People. New York: St. Martin's Press, 1992.

"The Beginnings." Boeing History. http://www.boeing.com/companyoffices/history/boeing.html.

Additional References:

Chant, Chris. The World's Great Bombers. New York: Amber Books Ltd., 2000.

Hallion, Richard P. Test Pilots: The Frontiersmen of Flight. Washington, D.C.: Smithsonian Institution Press, 1988.

Mansfield, Harold. Vision, the Story of Boeing. New York: Madison Publishing, 1986.

Pattillo, Donald. Pushing the Envelope The American Aircraft Industry. Ann Arbor, Mich.: The University of Michigan Press, 1998.

Rodgers, Eugene. Flying High The Story of Boeing and the Rise of the Jetliner Industry. New York: The Atlantic Monthly Press, 1996.

Yenne, Bill. Legends of Flight. Lincolnwood, Ill.: Publications International, Ltd., 1999.

Educational Organization

Standard Designation (where applicable

Content of Standard

International Technology Education Association

Standard 6

Students will develop an understanding of the role of society in the development and use of technology.

International Technology Education Association

Standard 7

Students will develop an understanding of the influence of technology on history.

International Technology Education Association

Standard 8

Students will develop an understanding of the attributes of design.