The American term given to airplanes that are predominantly the lifting component, the wing.
Before the invention of the airplane, English physicist Sir George Cayley, who in 1853 built the first manned glider, suggested that flying machines would be most efficient if they were only a wing. After the airplane became a reality in the early twentieth century, most successful airplane designs were linear. Their noses sported vertical or horizontal stabilizers, or perhaps an engine, and worked backward toward the cockpit, wings, rudimentary fuselage, and vertical or horizontal stabilizers, or both.
Airplanes are engineered to suit mathematical logic and economic reality. Pilots seek aerodynamic poise, while passengers seek comfort and amenities. Operators measure an aircraft’s reliability, and accountants measure its economy. Most people also judge airplanes for their inspiring beauty. One design, the flying wing, exhibited grace, economy, and performance. Inspired by Cayley’s belief in eliminating the drag and weight of fuselages and tails, the flying wing has long been aviation’s Holy Grail. Because all-wing airplanes need fewer parts and construction steps than do conventional designs, they are more energy-efficient both to build and to operate. Still, flying wings are rare.
During and after World War I, the development of aircraft engines quickly overpowered the aerodynamic drag produced by early airplanes. This development spelled doom for the flying wing design. Because airplane designs were still new, people had little preconception of how airplanes should appear. By the 1940’s, airplanes had proved viable, and society’s view of airplanes included a fuselage and tail. The economic boom and low energy costs had made conventional designs inefficiencies tolerable.
The earliest flying wings, sporting vertical stabilizers, were not purely wing-only designs. In 1907, British airpline designer John William Dunne showed that conventional tails were unnecessary. His balanced aerodynamics have infused tailless and all-wing airplanes ever since. By 1930, Germany’s Walter and Reimar Horten first flew their model all-wing airplane, called a nurflügel in Germany. In 1933, the Hortens flew a manned all-wing glider model called the HO-1. Knowledge gained from the HO-1 inspired the HO-5, a twin-engine machine potentially leading to an all-wing fighter. German general Ernst Udet, long appreciating the Hortens’ nurflügel ideas, succumbed to political blame for other project failures and in November, 1941, took his own life. Germany’s all-wing idea had lost a patron, and the proposed all-wing fighter languished until 1945, when advancing American soldiers discovered one nearly completed twin-jet HO-9 fighter. Other Horten all-wings flew as developmental projects. However, the most ambitious project, the HO-18 long-range heavy bomber, remained only an idea.
In the United States, John Knudsen Northrop dreamed of flying wings. His single-seat 1933 design, the Model 1, had thin, tubular twin booms supporting a conventional horizontal stabilizer with twin rudders. Northrop began testing a true nurflügel in July, 1940, when the N-1M first flew. It was a flying laboratory, designed to change configurations between flights. Changes in wingtip droop, sweepback (the taper of the wing’s leading edge), and wing dihedral (angle of the wingtips) could provide a bank of information. The Americans considered building a medium bomber based on the N-1M. Encouraged, Northrop continued testing predominantly all-wing airplanes, including four N-9M engineering test airplanes. Although one N-9M crashed, the remaining crafts saw duty as trainers, giving pilots firsthand experience with the flight characteristics of all-wing airplanes.
Following World War II, Northrop built the prototype XB-35 all-wing bomber, a six-engine, propeller-driven pusher design that was a true wing-only machine. Jet engine technology was making propellers obsolete for combat airplanes, so Northrop soon rebuilt the XB-35 into the YB-49, an eight-engine all-jet bomber. Although the YB-49 project did suffer airplane loss, the design was sound, and officials who were influential in procurement favored the U.S. Air Force’s adoption of the YB-49. However, the project was mired in political intrigue, dooming America’s flying wing. So sour were the feelings of those involved that Air Force secretary Stuart Symington ordered not only the flying wing’s cancellation in 1950 but also the destruction of all XB airframes. None remained even for museum display.
Four decades later, on November 22, 1988, the Air Force unveiled the B-2 stealth bomber, designed by the Northrop Corporation, to the American public. Several years earlier, Northrop company officials had secretly revealed the airplane to the eighty-five-year-old Northrop, who died the following year, knowing that his dream would finally fly. In 1996, the McDonnell Douglas Corporation revealed its idea of a BWB-1 (blended-wing body) airliner to seat 800 passengers. Efficient design would permit the three-engine jet to operate at about two-thirds the cost of a conventional airplane of the same capacity. In 2001, Northrop Grumman used company funds to construct an all-wing uncrewed combat air vehicle (UCAV) for aircraft carrier use. With leading edges swept back 55 degrees and trailing edges sweeping forward 30 degrees, the inherently stealthy design was a logical step in airplane development toward autonomous, or “smart” aircraft. To meet the military’s need for extended endurance, the Northrop Grumman Corporation began to look at extensions on each wingtip, transforming the UCAV’s aggressive arrowhead shape into the more elegant, traditional all-wing design.
Campbell, J. M., and G. R. Pape. Northrop Flying Wings: A History of Jack Northrop’s Visionary Aircraft. Atglen, Pa.: Schiffer, 1995. A comprehensive examination of Northrop Aircraft’s triumphs and tragedies and of Jack Northrop’s impact on America’s ultimate all-wing bomber, includes a valuable selection of lists, drawings, and color and black-and-white photographs. Kohn, Leo. The Flying Wings of Northrop. Milwaukee, Wis.: Aviation Publications, 1974. A brief but well-researched text, with black-and-white photos and a good reproduction of Northrop Aircraft’s pilot manual for the YB-49 bomber. Myhra, David. The Horten Brothers and Their All-Wing Aircraft. Atglen, Pa.: Schiffer, 1998. A look at the personality-driven aviation industry, from the perspective of the all-wing’s chief proponents and opponents, with an excellent selection of black-and-white photographs and line drawings. Norris, G., and M. Wagner. Giant Jetliners. Osceola, Wis.: MBI, 1997. A well-researched and easily read discussion of heavy airliners, profusely illustrated with color photographs. Wall, R., and D. A. Fulghum. “New Demonstrator Spurs Navy UCAV Development.” Aviation Week and Space Technology 154 (February 19, 2001).
Sir George Cayley
Uninhabited aerial vehicles