![]() That shock wave tends to stand on the aircraft’s wing, creating drag, as the air has to flow over it. Around the speed of sound, the flatter top side minimized the effect of the standing shock wave that formed on the wing, while a downward-curving underside compensated with additional lift. The supercritical wing design is almost the inverse of what was the conventional design when it was invented. “As the object moves faster, approaching the speed of sound, these disturbances that travel at the speed of sound cannot work their way forward and instead coalesce to form a shock wave.” Comparison of conventional and supercritical airfoils “As an object moves through air, it collides with the air molecules, creating a disturbance that propagates away from the object by means of weak pressure waves-essentially sound waves,” explains Robert Gregg, chief aerodynamicist for Boeing Commercial Airplanes, headquartered in Renton, Washington. Whitcomb was well aware of the problem the wings needed to overcome to ease flight approaching the speed of sound. The best idea any of his supervisors came up with was to leave him alone except to help him through those administrative duties distracting him from what he really wanted to be doing.” “In some respects, management did not know exactly how to deal with him. “Though he had a conservative, shy personality, he was a radical in the laboratory,” NASA historian James Hansen wrote of Whitcomb in his history of Langley. The first aircraft used to test supercritical wing designs was a modified Vought F-8 Crusader provided by the US Navy. Vought F-8 Crusader using supercritical wing His supervisor suggested he research wing characteristics for an aircraft design being studied by the Ling-Temco-Vought Company. In the early 1960s, after several years of work on designing a Mach 2-rated jet-that is, one that could fly at double the speed of sound-he became frustrated and returned to the more familiar field of transonics, speeds at or around the speed of sound. By his own accounts, he’d been sitting at his desk, chain smoking and imagining wind as pipelines sweeping over the surface of his model when the idea hit him. ![]() Now known as the “area rule,” this is the idea that a fuselage that tapers where the wings are attached can pass the speed of sound more easily than the traditional bullet shape. ![]() ![]() Indeed, he hadn’t been calculating or even observing wind tunnel tests when he had the insight that earned him the Collier Trophy. “But he had this uncanny ability to accurately sense how air molecules reacted over a surface before he even built the models.” “Most people have to see through testing how air moves on a model,” Roy Harris, former aeronautics director at Langley, told the Washington Post in Whitcomb’s 2009 obituary. Later dubbed “the man who could see air” by the Smithsonian’s Air and Space Magazine, Whitcomb took an unconventional approach to aerodynamics, eschewing calculations in preference of visualization and intuition. He called it the “supercritical” airfoil. However, he was still working to improve flight efficiency at speeds approaching that barrier, now with a seemingly counterintuitive wing design, almost the inverse of what were then conventional wings. An eccentric who seemed most at home in the center’s wind tunnel facilities, where he was known to sometimes sleep between double shifts, Whitcomb tended to prefer intuition to calculation when working out designs. The supercritical wing was one of three major contributions Langley Research Center engineer Richard Whitcomb made to aeronautics. Sixteen years earlier, this Langley Research Center aeronautics engineer had received the 1954 National Aeronautic Association’s Collier Trophy, considered the most prestigious honor in aviation, for doing more than any other single person to overcome the aviation challenge of the day-the so-called sound barrier. Whitcomb was already something of a star in the aviation world. By the time he was visiting what is now known as Armstrong Flight Research Center to witness the first tests of his latest creation, Richard T.
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