conducted the first flight of the remotely piloted ( ) unmanned aircraft yesterday at the ’s Dryden Flight Research Center at Air Force Base in California. The flight lasted 9 minutes and the aircraft climbed to an altitude of 5,500 feet before landing back on the dray lakebed.
The X-48C is a modified version of the X-48B aircraft, which flew 92 times at NASA Dryden between 2007 and 2010. The X-48B’s flight test program proved that a BWB aircraft can be controlled as effectively as a conventional tube-and-wing aircraft during takeoffs and landings, as well as in other low-speed segments of the flight regime. Primary changes to the C model from the B model were geared to transforming it to an airframe noise-shielding configuration. “With the X-48C, we will be evaluating the impact of noise shielding concepts on low-speed flight characteristics,” said Bob Liebeck, aSenior Technical Fellow and the company’s BWB program manager. The modified test vehicle was designed by and built by Cranfield Aerospace Ltd., in the United Kingdom, in accordance with requirements.
The newer version has a 21-foot wingspan and its weight is 500 pounds. It is configured with two 89-pound thrust turbojet engines, instead of three 50-pound thrust engines on the B-model; and wingtip winglets have been relocated inboard, next to the engines on the C-model, effectively turning them into twin tails. The aft deck also was extended about 2 feet at the rear. The vehicle has an estimated top speed of about 140 miles per hour and a maximum altitude of 10,000 feet.
Engineers from Boeing Research & Technology, the company’s central research, technology and innovation organization, will be working closely with NASA engineers during flight tests of the X-48C, which are expected to continue throughout 2012. As handling qualities of the X-48C will be different than those of the X-48B, the project team developed flight control software modifications, including flight control limiters to keep the airplane flying within a safe flight envelope.
The X-48C project team consists of Boeing, NASA, Cranfield Aeropace, and the U.S. Air Force Research Laboratory.