A Boeing-designed futuristic aircraft with the potential to boost fuel efficiency significantly while reducing noise had a successful test flight, NASA said. The remotely piloted X-48C Blended Wing Body research aircraft, a scaled-down model of the proposed design, flew Tuesday at Edwards Air Force Base in California\'s Mojave Desert. Built by Cranfield Aerospace Limited in Britain, the X-48C has a wingspan of about 20 feet, weighs about 500 pounds and can fly up to 140 mph, reaching an altitude of 10,000 feet. Tuesday\'s flight lasted 9 minutes and reached 5,500 feet, seattlepi.com reported. The aircraft is a successor to the X-48B, which flew from 2007 to 2010. Modifications include moving wingtip winglets to the fuselage, extending the length by 2 feet and replacing the X-48B\'s three 50-pound thrust jet engines with two 89-pound thrust engines. \"In our earlier flight testing of the X-48B, we proved that a BWB aircraft can be controlled as effectively as a conventional tube-and-wing aircraft during takeoffs and landings and other low-speed segments of the flight regime,\" Bob Liebeck, Boeing\'s blended wing body program manager, said in a release. \"With the X-48C, we will be evaluating the impact of noise shielding concepts on low-speed flight characteristics.\"