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1995-04-05
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The primary function of the space shuttle was to provide a cargo carrier and platform to
carry components into orbit to allow astronauts to construct a permanent space station. It
was soon realized by NASA designers in the 1970s that building a space station would be
too expensive for the United States alone. An international coalition would be necessary.
Throughout the 1980s, engineers, scientists and designers working in nearly a dozen
nations came up with the International Space Station Freedom. The space station would
be built in stages over time, beginning in 1996 and becoming fully operational by the year
2000. Various modules and components would be built by various nations and launched
by the American shuttle fleet.
The American laboratory module would house internal experiments operated by the
astronauts. The European Space Agency would provide a second laboratory module.
Japan would provide a third laboratory module with a platform for external payloads and a
robotic arm. Canada would provide a robotic servicing system that will assemble Freedom
in orbit and assist astronauts in servicing the station.
However, it now seems that the risk of cost overruns was too much for the US
government, even with the burden being shared by other nations. After the breakup of the
former Soviet Union, the Russian Space Agency joined the list of participants in the
project. Nonetheless, NASA may be unable to get the required funding for the space
station. Without the participation of America's shuttle fleet, the space station will not get
off the ground.
During the early development of the current space shuttle orbiter, many designers were
working on single-stage-to-orbit vehicles, which would not need large and costly rocket
boosters. The X-15 aircraft was an early test model of such an idea. However, new
engines had to be developed that would be air breathing during atmospheric flight, but
also function in the vacuum of space.
Due to the severe budget limitations under which NASA designed and built the current
space shuttle, compromises had to be made. The space shuttle is indeed cheaper to build,
but it is also more expensive to operate. Now designers are looking again at single-stage-
to-orbit spacecraft. The results have been the X-30 and X-33 aircraft, both of which are
called the National Aerospace Plane.
This plane would carry a payload slightly less than that of the space shuttle orbiter.
However, it would take off and land like a conventional airplane, require less fuel, and
have greater maneuverability. Few debate the vast superiority that this vehicle would have
over the current shuttle in performance, economy, and safety.
NASA's current plans are to develop the National Aerospace Plane, and then give the
design to private companies who would build and operate the vehicles. NASA no longer
has the money to build and operate a new fleet of vehicles. For the near future, it is
unlikely that private companies would fund such a project. Unless this situation changes,
America's leadership in space may be in jeopardy.