Boeing completed the fi rst test fl ight of its latest unmanned X-48B blendedwing- body research aircraft, designated the X-48B, when it climbed to 7,500 ft at Edwards Air Force Base in California last month.

The unmanned test vehicle represents a possible future aircraft that replaces the traditional tube-and-wing design with a shape resembling a mantaray — essentially a fl ying wing.

The prototype, which has a 21-foot wingspan and weighs 500 pounds, fl ew for a half-hour at NASA’s Dryden Flight Research Center at Edwards Air Force Base, CA. Thanks to greater aerodynamic effi ciency, a blended-wing-body design could be built much bigger than current planes and carry more passengers or cargo.

For commercial applications, a big drawback is that most passengers in the cavernous interior would be far from windows. But Boeing is fi rst looking at such applications as military cargo. A company spokesman said that, with continued government funding, a blended-wing-body military-cargo plane could be in use sometime between 2015 and 2020.