This unique Dryden aircraft is finishing a test flight and refueling at sea.
In this historic photo from the U.S. space agency, Dryden's SR-71B, NASA 831, slices across the snowy southern Sierra Nevada Mountains of California in January of 1995, after being refueled by an Air Force Flight Test Center tanker during a recent flight.
The Mach 3 SR-71B aircraft are being flown by the Dryden Flight Research Center, Edwards, Calif., as testbeds for high-speed, high-altitude aeronautical research. Capable of flying more than 2200 mph and at altitudes of over 85,000 feet, they are excellent platforms for research and experiments in aerodynamics, propulsion, structures, thermal protection materials, atmospheric studies, and sonic boom characterization.
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