The cover story of Time magazine's Nov. 12 edition highlights the best inventions of the year for 2007. It covers the latest innovative products from the entertainment, transportation, environmental and several other high-tech areas. From the aircraft category, the magazine recognized Boeing's X-48B blended wing body (BWB) for its innovative design and its potential to enable cleaner, quieter and higher performance air transportation.
The BWB is a collaborative effort of the Boeing Co., NASA's Fundamental Aeronautics Program, and the Air Force Research Laboratory. The Air Force designated the aircraft as the "X-48B" based on its interest in the design's potential as a multi-role, long-range, high-capacity military aircraft.
The aircraft uses a hybrid shape that resembles a flying wing, but also incorporates some features of a conventional airliner. The futuristic airframe is a unique merger of efficient advanced wings and a wide airfoil-shaped body, causing the aircraft to generate lift-to-drag ratios, thereby increasing fuel economy.
Over the past several years, wind tunnel and free-flight tests have been conducted to study certain aerodynamic characteristics of the BWB design. At the NASA Langley Research Center in Hampton, Va., researchers conducted wind tunnel tests on two 21-foot wingspan prototype aircraft to evaluate the design's stability, control and spin/tumble characteristics. These 8.5 percent scale model aircraft used advanced lightweight composite materials and weighed about 500 pounds each. Powered by three turbojet engines, they can fly up to 138 miles an hour and as high as 10,000 feet during flight-testing. The data obtained from these tests were used to develop flight control laws and help define the flight research program.
On July 20, 2007, years of research, design, construction, wind tunnel and ground tests coalesced into the X-48B's first flight at the Dryden Flight Research Center on Edwards Air Force Base, Calif. In short order, the project team completed six highly successful flights. The aircraft then underwent four-weeks of maintenance and planned modifications to replace extended slat leading edges with slatless leading edges and update the flight control software. This would help the team evaluate the aircraft in a slats-retracted configuration.
NASA's Subsonic Fixed-Wing Project, part of the Fundamental Aeronautics Program, is interested in the potential benefits of the aircraft to include increased volume for carrying capacity, efficient aerodynamics for reduced fuel burn, and, possibly, significant reductions in noise due to propulsion integration options.
During the initial flights, the primary focus was to validate prior research on the aerodynamic performance and controllability of the shape, including comparisons of flight test data with the extensive database gathered during the Langley wind tunnel tests.
Up to 25 flights are planned to gather data in the low-speed flight regime. The X-48B may then be used to test the aircraft's low-noise and handling characteristics at transonic speeds.
To see Time magazine's photo story on the BWB, visit: www.time.com. For more information about NASA's aeronautics programs, visit: