The Martin Marietta X-24A was a project sponsored by the
USAF Flight Development Laboratory (FDL).
The X-24A program was run alongside the NASA
HL-10 project. Both aircraft were developed to test
the principle of lifting body aircraft, and help produce
a manned re-entry vehicle. The lessons learnt from the
aircraft, and subsequent programs, were used to help develop
the Space Shuttle.
During its flight trials at the Edwards Air Force Base
in California, the X-24A was carried aboard a B-52B mothership
up to altitude. Once released the X-24A pilot would fire
the aircraft's rocket motor for 2.5 minutes and climb
up to 70,000 ft (21,336 meters), reaching a top speed
of 1,036 mph (Mach 1.6) along the way. The X-24A would
then glide back to the ground unpowered.
The Martin Marietta X-24A was flown a total of 28 times
by three different pilots (Jerauld R. Gentry, John A.
Manke and Cecil W. Powell) from 1969 to 1971. In 1972
the X-24A was comprehensively redesigned and renamed the
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