The Boeing B-17 â€œFlying Fortressâ€ is a World War II American heavy bomber used primarily in Europe and that helped turn the tide in the battle of World War II.
Boeingâ€™s corporate historian, Michael Lombardi said, â€œThe B-17 and the United States Army Air Forces strategic warfare strategy was instrumental in destroying the German air force and ensuring that the only airplanes that would be flying over the beaches of Normandy on D-Day would be Allied airplanes. After D-Day, continued attacks on vital war munitions, petroleum and manufacturing accelerated the collapse of Nazi Germany.â€
Boeing Chairman Claire Egtvedt, the â€œfatherâ€ of the B-17, set Boeing on a new course to build â€œbigâ€ airplanes, rather than the smaller aircraft popular at that time.
Egtvedt, along with Boeing designers C.N. â€œMontyâ€ Monteith, Robert Minshall, E.G. Emery and Ed Wells, all had the vision of designing an aircraft with four engines rather than the standard two-engine design, in order to meet the U.S. Armyâ€™s request for a multi-engine bomber.
The decision saved the B-17 (Model 299) prototype, from being a footnote in aviation history. The project financed entirely by Boeing, went from design board to flight test in less than 12 months.
The B-17 was a low-wing monoplane that combined aerodynamic features of the XB-15 giant bomber, which was still in the design stage, and the Model 247 transport.
The B-17 was the first Boeing military aircraft with a flight deck instead of an open cockpit and was armed with bombs and five .30-caliber machine guns mounted in clear â€œblisters.â€
In 1934, the Boeing Aircraft Company of Seattle, Wash., began construction on the four-engine heavy bomber. The Boeing model 299 took its first flight on July 28, 1935, from Boeing Field in South Seattle.
Seattle Times reporter Richard Smith dubbed the new plane, with its many machine-gun mounts, the â€œFlying Fortress,â€ a name that Boeing quickly adopted and copyrighted.
Boeing test pilot Les Tower took the model 299 for its first flight that July day and later made a record-breaking flight from Seattle to Wright Field in Dayton, Ohio. The aircraft was to fly against its competition, the Douglas DB-1 (B-18). Tower died from injuries sustained when the Model 299 crashed.
Boeing delivered more than 12,000 B-17s during the war. That number includes the 3,000 that came off the Douglas Aircraft assembly line, between 1942 through 1945, in Long Beach, Calif.
The B-17 underwent a number of improvements over its 10-year production span. Models ranged from the YB-17 to the B-17-G model.
Throughout the War, the B-17 was refined and improved as battle experience showed the Boeing designers where improvements could be made.
The government ordered production of 13 of the now designated Y1B-17. Delivery of these first production models was between Jan. 11 and Aug. 4, 1937.
The first B-17s saw combat in 1941, when the British Royal Air Force took delivery of several B-17s for high-altitude missions. As World War II intensified, the bombers needed additional armament and armor.
The B-17E, the first mass-produced model Flying Fortress, carried nine machine guns and a 4,000-pound bomb load. It was several tons heavier than the prototypes and filled with armament.
It was the first Boeing airplane with the distinctive and enormous tail for improved control and stability during high-altitude bombing. Each version was more heavily armed.
â€œThe men of the â€˜Mighty Eighthâ€™ based in England, and the 15th Air Forces based in Italy, flew up to 50 missions into the heart of the enemyâ€™s homeland with only heated flight suits and oxygen masks to protect them from an environment similar to that at the top of Mount Everest,â€ said Lombardi. â€œThey faced an even greater danger from the expert pilots of the German Luftwaffe and some of the heaviest anti-aircraft fire in history, all determined to destroy the American bombers.â€
In the Pacific, the planes earned a deadly reputation with the Japanese, who dubbed them â€œfour-engine fighters.â€ The Fortresses were also legendary for their ability to stay in the air after taking brutal poundings.
In World War II, aircrews liked the B-17 for its ability to withstand heavy combat damage and still return its crew safely home.
Because of their long-range capability, formations of B-17s often flew into battle with no fighter escort, relying on their own defensive capabilities to ensure a successful mission.
Between 1935 and May of 1945, 12,732 B-17s were produced. Of these aircraft, 4,735 were lost during combat missions. Production peaked at 16 airplanes a day in April 1944.
The final B-17 production model, the B-17G, was produced in larger quantities (8,680) than any previous model and is considered the definitive â€œFlying Fort.â€ With its 13 .50-caliber machine guns – chin, top, ball and tail turrets; waist and cheek guns – the B-17G was indeed an airplane that earned the respect of its combatants.
Lombardi said, â€œThe sacrifice was great, the air war in Europe claimed the lives of more than 30,000 American fighter and bomber crews and nearly half of the over 12,000 B-17s built for the war.â€
During the War, B-17s were among the most modern aircraft in the U.S. inventory. However, the advent of the jet age and advances in technology made the Flying Fortress obsolete soon after the conclusion of the War. The B-17 is now dwarfed by modern-day bombers and jumbo jets.
In the years following World War II, most B-17s were cut up for scrap, used in Air Force research or sold on the surplus market.
Some of the last Flying Fortresses met their end as target drones in the 1960s â€” destroyed by Boeing Bomarc missiles.
Today, fewer than 100 B-17 airframes exist and there are about a dozen B-17s still flying. At one time, more than 1,000 B-17s could be assembled for mass combat missions.
Some of the flying examples that still remain include: Aluminum Overcast, Yankee Lady, My Gal Sal, Nine-O-Nine, Sally B, Texas Raiders and Sentimental Journey.
Picadilly Lilly II is being restored to flight status at the Planes of Fame Museum in Chino, Calif.
Memphis Belle, one of the first B-17s to complete a tour of duty of 25 missions in the 8th Air Force, is now being restored for display at the USAF Museum in Dayton, Ohio, along with the Swoose, the oldest surviving B-17D, built in 1940.
Liberty Belle, a former engine test bed was restored as flying example, but was destroyed in a forced landing June 31, 2011, outside of Chicago, Ill., with no fatalities.
Research shows the B-17 underwent a long series of small modifications and successive production advancements during its mission lifetime. These advancements improved the performance of the aircraft. The data was collected over thousands of mission flight hours. Mechanics in World War II had to rely on what the aircrews reported and what they observed during ground testing.
â€œNowadays, in comparison, technology is recording and transmitting critical system performance data to ground systems with advanced software to analyze and isolate problems on an aircraft before it lands,â€ said Terry Langerman, Boeingâ€™s C-17 Globemaster III sustainment and affordability director.
But beyond the technical wonders of its day and the legacies of modern aircraft, no one can take away the romance crews held for the Flying Fortress.
â€œThe stable and rugged B-17 to this day is still loved by her crews who called her â€˜Queen of the Skies,â€™â€ said Lombardi. â€œThe affection was well earned; there are volumes of stories of B-17s that returned their crews safely to their bases, so badly damaged that they never flew again. â€œ
Lombardi stated that, Gen. Carl Spaatz, the American air commander in Europe, summed it up by saying: â€œWithout the B-17 we may have lost the war.â€
â€œThe success of the B-17 and her crews made the plane an icon of American air power and made a solid reputation for Boeing,â€ added Lombardi.
B-17G Flying Fortress general characteristicsÂ
Primary function: Bomber
Primary designer/builder: Boeing, Vega Aircraft Company (now Lockheed), Douglas Aircraft
Wingspan: 103 feet, 9 inch
Wing area: 1,420 square feet
Length: 74 feet, 4 inch
Height: 19 feet, 1 inch
Crew: Ten-Pilot, Co-pilot, Navigator, Bombardier, Flight Engineer (top turret gunner), Radio Operator, 2 Waist Gunners, Tail Gunner and Ball Turret Gunner
Empty: 34,000 pounds
Operational: 65,500 pounds
Maximum speed: 300 mph at 30,000 feet
Cruising speed: 170 mph
Service ceiling: 35,600 feet
Range: 1,850 miles. Range could be extended when equipped with â€œTokyo Tanksâ€ which provided a total capacity of 3,630 gallons
Engines: 4X Wright Cyclone Model R-1820-97, engines. These engines are nine cylinder, radial, air-cooled type with a 16:9 gear ratio. The propellers are three-bladed Hamilton Standard propellers, 11 feet, 7 inch, in diameter.
Engine power developed: 1,200-horsepower each
Guns: Thirteen Browning M-2 .50 caliber machine guns. Fire rate approximately 13 rounds per second. No gun on a B-17 carried more than one minuteâ€™s supply of ammunition.
Bombs/Rockets: Depending on types of bombs, maximum normal load could go to 8,000 pounds. If B-17 was fitted with special external racks, maximum normal short-range bomb load could go as high as 17,600 pounds.