Fact Sheet #6
The Policy Origins of the X-33
Part VI: The DC-XA
December 22, 1999
This is the sixth of a continuing series
of historical fact sheets on the origins of NASA's X-33 program. The X-33 is a technology
demonstrator for NASA's "next generation" of space launch vehicle. It will
flight test a range of technologies needed for single-stage-to-orbit reusable launch
vehicles, such as thermal protection systems, composite cryogenic fuel tanks, and
the aerospike engine. Currently, there is no announced schedule of test flights.
Eventually, based on the X-33 experience shared with NASA, Lockheed Martin hopes
to build a commercial single-stage-to-orbit reusable launch vehicle, called VentureStar.
In the future, rather than operate space transport systems as it has with the Space
Shuttle, NASA has proposed purchasing launch services from Lockheed Martin and other
commercial launch providers.
The decision to design and build the X-33 grew out of a NASA study called Access
to Space. Previous fact sheets have dealt with the Access to Space study and its
conclusions, the emergence of a tentative NASA program to build an experimental advanced
technology demonstrator flight vehicle, the X-2000, public and Congressional support
for a single-stage-to-orbit spaceship, and the funding difficulties of the country's
only single-stage-to-orbit vehicle program, the DC-X.
This fact sheet explores enthusiasm for single-stage-to-orbit projects at the
time of the Access to Space study and the proposed joint NASA-Department of Defense
program to develop new single-stage-to-orbit launcher technologies through both ground
research and flight testing on an experimental (or "X") vehicle, that grew
out of the Option 3 portion of the Access to Space study. It then follows the transfer
of the DC-X to NASA as the X vehicle for testing single-stage-to-orbit technologies
on an actual craft, then discusses the novel use of the cooperative agreement as
part of NASA's "new ways of doing business," and ends with the flight tests
of the DC-XA, known also as the Clipper Graham.