Boeing B-17G Flying Fortress

On July 16, 1935, "Seattle Times" editorial journalist, Richard L. Williams, noted the machine guns bristling from Boeing's Model 299 (the XB-17 prototype), and then wrote a story on the "fifteen ton Flying Fortress." The name stuck and the U. S. Army Air Corps made it official. But the years of intense combat during World War II showed what a Flying Fortress the B-17 really was. Described by General Henry H. "Hap" Arnold, wartime commander of the U. S. Army Air Forces, as the "backbone of our worldwide aerial offensive," the Flying Fortress served in all theaters of the war and captured the public imagination primarily as the symbol of the daylight bombing campaign against Nazi Germany.

In 1934, the Air Corps requested bids from the U. S. aircraft industry for a new multi-engine bomber. The airplane had to carry 909 kg (2,000 lb) of bombs a distance of 2,000 miles (3,220 km) at a speed of 200 mph (322 kph). Using company money and staking the firm's future on the results, Boeing developed the 4-engined Model 299 and its first flight, on July 28, 1935, demonstrated a performance that exceeded all bombers, and most fighters, then in military service. Unfortunately, three months later, the prototype crashed at Wright Field during the Army evaluation flights. A design flaw did not cause the crash but Boeing failed to win the production contract. Nonetheless, the Air Corps was impressed enough to order 13 service-test models called YB/Y1B-17s.

These aircraft demonstrated the potential to carry out long-range strategic bombing and Air Corps leaders ordered 39 B-l7B production airplanes in August 1937. This model differed from the service-test models by having a larger rudder and flaps and an improved sight widow for the bombardier. Although airpower advocates believed in the Flying Fortress, getting the Army General Staff to accept the strategic bombing concept was difficult. By 1939, the Air Corps had accepted only 13 B-17s but that year, the situation changed dramatically after President Franklin Roosevelt began to legislate dramatic increases in weapons production.

Two years later, 38 B-l7Cs followed, and the War Department sent twenty of them to the Royal Air Force (RAF) in the spring of 1941. The C model Flying Fortresses was heavier and had more powerful Wright R-1820-65 engines. The armament stations and gun configurations were also modified. In July, these bombers became the first Flying Fortresses to get tested in actual combat. RAF crews identified many deficiencies and were generally dissatisfied with the aircraft. There was insufficient armament and armor, and self-sealing fuel and oil tanks were lacking. The next model, the B-17D, adopted some of these improvements but the model that followed, known as the E model, marked a turning point in the design.

When the B-17E flew in September 1941, it sported a brand-new, redesigned aft fuselage with a much larger vertical fin and rudder and a tail gun station. To accommodate the new tail, Boeing engineers lengthened the fuselage by almost six feet. They also added manned, motor-driven gun turrets in the belly and dorsal fuselage area and more handheld weapons in the nose. Boeing increased the size of all 13 machine guns from .30 to .50 caliber. The number of Flying Fortresses in the Air Corps jumped to 200 by the time the Japanese attacked Pearl Harbor in December 1941.

The first of 512 E models built by Boeing arrived in combat units just before Pearl Harbor. The B-17C and D versions, fielded by the 19th Bombardment Group, flew the first U. S. offensive bombing missions when they attacked invading Japanese forces in the Philippines and the Dutch East Indies. The E model quickly replaced those war-weary Flying Fortresses that bore the brunt of the early fighting but by mid-1943, the B-17 had largely disappeared from the Pacific Theater. Consolidated B-24 Liberators with greater range replaced them.

The first B-17Es arrived in Europe during the early summer of 1942, and U. S. Army Air Forces (AAF) crews flew their first mission in these Flying Fortresses on August 17. They struck a German rail center at Rouen, 87 mi (140.1 km) northwest of Paris. In broad daylight from 25,000 ft (7,600 m), 12 B-l7Es flown by men in the 97th Bomb Group bombed freight yards, trains, and roundhouses. This small raid marked the beginning of the U. S. bombing offensive over Europe. Eventually, missions comprised as many as one thousand B-17s.

Before such raids could occur, the Army had to increase production. Assembly lines at the Boeing plant churned out Flying Fortresses night and day, yet the bombing campaign demanded more. The Lockheed Vega factory at Burbank, California and the Douglas plant at Long Beach co-produced the improved B-17F. The three companies turned out 3,405 F models. The last production Flying Fortress variant was the G. Aside from a new 'chin' turret mounting two .50 caliber machine guns, the G differed only in detail from the F. A total of 8,680 G models were built at all three plants. When the last B-17 rolled off the line on April 9, 1945, a grand total of 12,371 Flying Fortresses had been built by Boeing (6,981), Douglas (3,000), and Lockheed (2,750).

The B-17 Flying Fortress dropped more bombs than any other American warplane in World War II and in the crucible of combat, it remained true to its name. Approximately 4,750 were lost but thousands returned from raids riddled by bullets and cannon shells, one or more engines shot to pieces, and wings and tail surfaces twisted and torn.

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