NASA's blended wing-body Boeing X-48 has passed to 100-flight mark, a new high point for unmanned X-planes. The 100th flight was logged at Edwards AFB, California, on October 30, on the aircraft's eighth flight as the X-48C.
All photos: NASA
One of two built for Boeing by Cranfield Aerospace in the UK, the 21ft-span X-48 is an 8.5% dynamically scaled model of a blended wing body (BWB) design. The aircraft flew 92 times as the three-jet X-48B, to evaluate the low-speed flight-control characteristics of a large flying-wing airliner.
The second X-48B was modified into the C model, powered by two larger (but still small) turbojets and with the vertical stabilizers moved inboard and the trailing edge between the fins extended aft. These changes enable the X-48C to represent a BWB designed to minimize airport noise - the current focus of NASA's work.
Moving the engine nacelles forward, the fins inboard and extending the aft deck rearwards are all designed to increase shielding of jet noise by the airframe when viewed from the ground. Studies suggest only the BWB configuration has the potential to meet NASA’s noise goal for a 2025-timeframe airliner – a cumulative 42dB below Stage 4.
NASA Dryden Flight Research Center says the X-48C is planned to fly another 20 or so times this year. As it doesn't look like the agency will get funding to build the bigger, 737-size manned demonstrator it hoped for (below), the X-48 is as big as a BWB gets, for a while - until someone starts to get serious about the next large airlifter, or freighter.