Used By NASA For Wind Tunnel Testing

A flying model NASA built to research futuristic aircraft designs will spend its future in the United States' premier air and space museum.

The 12-foot wing span blended wing body, or BWB, model, used during wind tunnel flight tests at NASA's Langley Research Center in Hampton, VA is on long-term loan to the "How Things Fly" gallery at the Smithsonian Institution's National Air and Space Museum in Washington.

"One key focus of NASA aeronautics research is to develop technologies to make aircraft more fuel efficient and environmentally friendly," said Jaiwon Shin, associate administrator for NASA's Aeronautics Research Mission Directorate in Washington. "Because of these technologies, airplanes may look very different 20 years from now. This model will give visitors to the Smithsonian a glimpse into the future of air travel."

The model was tested in a wind tunnel to help engineers better understand how the blended wing body handles. The five-percent scale model has 18 control surfaces along the trailing edges of the wing, compared to four on most airplanes. Those four are the rudder, the ailerons, the elevator and the flap. One of the challenges to controlling a flying wing is determining how to blend the control surfaces to make the vehicle turn and climb.

The blended wing body resembles a flying wing, unlike today's "tube-and-wing" aircraft. "When you get rid of the tail you have to come up with different ways to control the plane," said Dan Vicroy, a senior research engineer at Langley. "We have a lot of experience with conventional airplanes. We know how to predict how they are going to fly. But with this type of a flying wing design, we have fewer examples and less confidence in our flying quality estimates."

Vicroy led the "free flight" experiment in the Langley Full Scale Tunnel's huge 30-by-60-foot test section. "We actually flew this BWB in the tunnel in 2005," said Vicroy. "We had control systems on board the model as well as high pressure air that we used to simulate the engines." The model was constrained only by a tether cable.

In the National Air and Space Museum, the blended wing body model will hang from the ceiling about 15 feet above visitors' heads. "The model is an important part of a facelift of the gallery that we hope will be done by March 2009," said Michael Hulslander, the How Things Fly gallery manager. "This is the most visited gallery in the museum, and the BWB will be the largest artifact in it."

Research on blended wing body designs continues in the Subsonic Fixed Wing Project of NASA's Fundamental Aeronautics Program. They are part of hybrid wing body research into acoustics, structures, aerodynamics and flight controls.

FMI: www.nasa.gov/topics/aeronautics/features/bwb_main.html