A total of 30 flights of the aircraft were conducted at NASA's Dryden Flight Research Center to explore and further validate the aerodynamic characteristics of the blended wing body design concept.
The X-48C is a triangular-shaped aircraft without a tail. Its wings and body are merged, unlike the conventional tube-and-wing formulation. It was designed by Boeing and built by Cranfield Aerospace Ltd., and flown in partnership with NASA and the U.S. Air Force Research Laboratory.
The aircraft tested was a scale model of a heavy-lift, subsonic vehicle.
Boeing said flight tests typically lasted 30 minutes, during which time the aircraft reached an altitude of 10,000 feet and achieved the speed of 140 miles per hour.
"Working closely with NASA, we have been privileged throughout X-48 flight-testing to explore and validate what we believe is a significant breakthrough in the science of flight – and it has been a tremendous success for Boeing," said Bob Liebeck, a Boeing senior technical fellow and the company's BWB program manager.
"We have shown that a BWB aircraft, which offers the tremendous promise of significantly greater fuel efficiency and reduced noise, can be controlled as effectively as a conventional tube-and-wing aircraft during takeoffs, landings and other low-speed segments of the flight regime."
The X-48C is a modified version of the X-48B aircraft, which was flown between 2007 and 2010. It has two 89-pound thrust turbojet engines, whereas the "B" had three 50-pound thrust engines. It also is two feet longer than its predecessor.
"With the completion of X-48C flight testing, we have accomplished our goal of establishing a ground-to-flight database, and proving the low-speed controllability of concept throughout the flight envelope," said Fay Collier, director of NASA's Environmentally Responsible Aviation project. "Both very quiet and efficient, the concept has shown promise for meeting all of NASA's environmental goals for future aircraft designs."
Boeing and NASA are planning to continue developing the design concept to produce a larger-scale, transonic BWB demonstrator.