- SEATTLE (Reuters) - Aviation
experts believe NASA will not replace the lost space shuttle Columbia for
about 10 years, sticking to a schedule that may force the agency to rely
more on Russia to supply the International Space Station.
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- Building a replica shuttle would be too costly, leaving
a next-generation "orbital space plane" due to enter service
around 2010 as the earliest possible relief for the remaining three shuttles,
which could keep flying for decades to come, according to experts advising
NASA and the White House.
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- Columbia, which disintegrated over Texas on Saturday,
killing all seven astronauts on board, was the oldest shuttle in the fleet.
It was deemed too heavy for space station docking, but the vehicle had
been expected to carry out a range of science experiments in space that
might now be shifted to the newer shuttles.
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- "The remaining three shuttles will be fully booked
for space station crew launches and resupply. Some of that can be done
with Progress and Soyuz (Russian spacecraft), but shuttles were the mainstay
for the science experiments," said Norine Noonan, dean of math and
science at the College of Charleston and a NASA Advisory Council member.
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- Last November, NASA pushed back plans to retire the shuttle
fleet in 2012 and retooled its Space Launch Initiative to focus on breakthrough
technologies to reduce space flight costs to facilitate a complete shuttle
replacement.
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- As part of that program, Boeing Co., which bought the
Rockwell unit that built the shuttles and is now a primary shuttle contractor,
plans to test fly its space plane technology demonstrator, the X-37, in
2004.
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- The pilotless, 27.5-foot-long (8.5-meter) X-37 will be
dropped from a B-52 bomber at 45,000 feet, testing its aerodynamics and
its ability to resist the blazing heat spacecraft endure when re-entering
Earth's atmosphere.
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- SHUTTLE REPLICAS UNLIKELY
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- The shuttle, deemed extremely reliable despite the Columbia
disaster on Saturday and the Challenger explosion in 1986, which also killed
seven astronauts, uses decades-old technology and has been out of production
since the Endeavour was built in 1987.
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- Rather than scrambling to resurrect that program, costing
billions, most experts advocate staying focused on the space plane, which
would ship crews and supplies to the space station and pave the way for
a full-scale shuttle successor.
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- "I don't think you could build a new shuttle if
you wanted to. All the production facilities were shut down and I'm not
sure the tooling is still there," said John Logsdon at the Space Policy
Institute of George Washington University.
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- Still in the design phase, the space plane would be launched
on expendable rockets -- later replaced with advanced, reusable launch
vehicles near the middle of the next decade.
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- "The orbital space plane would be much wiser (than
a new shuttle) and the question is whether you could advance that timetable.
It certainly would not be inexpensive," said Robert Walker, a former
U.S. representative who chaired a presidential commission on the future
of the U.S. aerospace industry.
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- Official cost estimates are not expected until 2004,
but analysts say building a new, two-stage shuttle replacement could cost
$30 billion or more.
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- RELYING ON RUSSIA
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- Russia is considered a full partner in the International
Space Station and has delivered "very robust technology" and
reliable supply missions, although "we have not had such a good experience
with them in building components," Walker said.
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- Soyuz ships make fine crew taxis, but have limited capacity
for scientific experiments, meaning NASA may need to spend its limited
cash on Russian launches if the current shuttle fleet gets bogged down
with science missions, or in an emergency.
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- "It's my understanding that the Russians don't have
many vehicles left to pick up the slack. So they are going to ask for money
to fill in," Walker said. "That's a very important decision:
to develop your own program or pay the Russians." (Additional reporting
by Deborah Zabarenko in Washington))
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