UNIQUE WIND TUNNEL REVOLUTIONIZED AERONAUTICAL TESTING
NASA'S NATIONAL TRANSONIC FACILITY TURNS 20
It has always been a challenge to test scale models in wind
tunnels and approximate actual flight conditions, especially at
speeds that approach and exceed the speed of sound (Mach 1). To get
accurate test results, models had to be big, meaning bigger
tunnels; the pressure in the tunnel had to increase substantially,
which could cause unwanted distortion of the models; or the
tunnel's temperature had to decrease substantially. Until the
National Transonic Facility (NTF) opened, the feasibility of a
tunnel that could accomplish those conditions was not
Researchers at NASA's Langley Research Center, Hampton, Va.,
designed and developed a new type of cryogenic (low-temperature)
tunnel that would give the scientists the conditions they needed to
test the new generation of aircraft.
NASA's National Transonic Facility celebrates its twentieth year
of operation on December 6, 2003. Construction of the NTF began in
1979. Vice President George Bush attended the ribbon-cutting
ceremony opening the facility in 1983.
Media Opportunity: Members of the media who would like
the rare opportunity to tour the NTF and speak to researchers on
Thursday afternoon, December 4, should contact Bill Uher at (757)
864-3189 or 344-6811 (mobile) to arrange for credentials.
The 497-foot-long, 230,000 cubic foot tunnel is constructed of
over half a million pounds of aluminum and stainless steel. Powered
by a 135,000 horsepower turbine motor and cooled by liquid
nitrogen, the NTF can achieve velocities of Mach 1.2 at 120 pounds
of pressure per square inch and run at temperatures between -250
and +150 degrees
Some notable vehicles tested in the NTF include: Boeing 777,
Space Shuttle and Booster, Boeing 767, Blended Wing Body designs
including the B-2 Bomber, A-6 Intruder and the F-18 Hornet.