This is an artist's concept of the X-34 Demonstrator, a reusable technology testbed vehicle that was designed to demonstrate technologies that were essential to lowering the cost of access to space. Powered by a LOX and RP-1 liquid Fastrac engine that was designed and built by the Marshall Space Flight Center, the X-34 would be capable of speeds up to Mach 8 and altitudes of 250,000-feet. The X-34 program was cancelled in 2001.
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