Lockheed X-17
From the placard:
The Lockheed X-17 is a three-stage, solid fuel research rocket
produced for the Air Force in the 1950s. It was developed primarily
to test the effects of heating on ballistic missile nose cones
reentering the Earth's atmosphere. On a typical research mission, the
X-17 was launched by the first stage into a ballistic trajectory. The
first stage burned out at approximately 90,000 feet, but the vehicle
coasted upward to more than 500,000 feet. On the fall back toward
Earth, the X-17 pitched nose down, the spent first stage was
jettisoned, and the second stage was fired. The second stage was then
jettisoned and the thrid stage was fired, pushing the X-17 downward at
a speed between Mach 11.2 and 14.5. Instruments relayed data to the
ground by radio telemetry. The Air Force also used the X-17 on three
Project Argus research flights in 1958 to test nuclear warheads in
space by exploding them at an altitude of 300 miles. The X-17 on
display has been painted as one of the Project Argus vehicle.
