Remote-Control Scale Model To Fly Before End Of '06

Is it the military's aerial tanker/transport/bomber of the future... or a future Boeing A380-fighter (and successor to the cancelled Sonic Cruiser program)? Well, it could one day be both... but at the moment, the X-48B is an eight-and-one-half-percent scale model of an advanced concept, fuel-efficient "blended wing" airplane designed and built to test the concept of Blended Wing Body aircraft at NASA's Langley Research Center.

The model -- looking like a huge bird perched atop three utility poles inside Langely's massive wind tunnel -- features a 21-foot wingspan. Most significantly, the BWB does not feature a conventional tube fuselage... or a vertical tail structure.

"The biggest difference between this aircraft and the traditional tube and wing aircraft is that this does not have a tail," said Dan Vicroy, senior research engineer at NASA Langley.

"The whole reason you have a tail is for stability and control. So what we want to do with this wind tunnel test is to look at how different multiple control surfaces can be used to control this particular vehicle," Vicroy said.

Boeing engineers say the concept offers several advantages over a conventional airplane -- not the least of which is about 30 percent greater fuel efficiency over a conventionally-designed aircraft offering the same capabilities.

Boeing Phantom Works' advanced research and development unit partnered with NASA and the US Air Force Research Laboratory (AFRL) at Wright Patterson Air Force Base to explore and confirm the structural, aerodynamic and operational advantages of the blended wing body design.

"We believe the BWB concept has the potential to cost effectively fill many roles required by the Air Force, such as tanking, weapons carriage, and command and control," said Captain Scott Bjorge, AFRL’s X-48B program manager.

So far, two models have been built to Boeing's specifications by Cranfield Aerospace in England -- one for wind tunnel testing, the second one for actual flight.

"The X-48B prototypes have been dynamically scaled to represent a much larger aircraft and are being used to demonstrate that a BWB is as controllable and safe during takeoff, approach and landing as a conventional military transport airplane," said Norm Princen, chief engineer for the X-48B program at Boeing Phantom Works.

X-48B Ship No. 1 is the wind tunnel test model. After testing is finished at Langley, it will be shipped to NASA's Dryden Flight Research Center at California's Edwards Air Force Base to act as a backup for a second X-48B prototype.

Ship No. 2 is scheduled to be used in remotely-piloted flight testing later this year at Dryden.

For now, the focus of the BWB project is on potential military applications... but it's not hard to imagine commercial applications for the design, as well (after all, the original Boeing 707 was developed alongside the Air Force's KC-135 tanker concept.) NASA has explored the concept for several years, as the above photo from 1997 indicates.

Industry says a blended wing body military aircraft could be in service within 10 to 15 years, if testing and program funding go well.

FMI: www.boeing.com, www.nasa.gov