August 9, 2005

Beyond Discovery, Shuttle Faces Uncertain Future

CAPE CANAVERAL, Fla. -- The space shuttle Discovery may have put NASA back into the human spaceflight business after the 2003 Columbia disaster, but it will be up to shuttle Atlantis to keep it there.

That may not happen for some time.

Discovery returned on Tuesday from a 14-day mission to test post-Columbia safety upgrades and resupply the International Space Station.

"I think we met the milestone of return to flight and the next test-flight is in the works," said shuttle program manager Bill Parsons.

But the planned launch of Atlantis on NASA's next shuttle mission in September was in doubt after the space agency found that the $1 billion and 2-1/2 years of effort spent on fixing a problem that doomed Columbia had failed to produce the hoped-for results.

Columbia was destroyed after falling foam from its external fuel tank ruptured the wing on takeoff. Sixteen days later, on Feb. 1, 2003, the spacecraft fell apart over Texas when the tremendous heat of re-entry ate into the breach.

When Discovery took off on July 26, foam insulation also fell from its tank, which had been billed as the safest ever to fly. NASA was forced to ground the rest of the fleet until the problem is solved.


NASA has appointed several teams to investigate the foam loss and recommend a fix. Parsons said he expects to get some preliminary findings as early as this week.

"Now that we have Discovery on terra firma, we'll go work these other issues," he said.

One team is investigating if the largest piece of foam, part of an aerodynamic ramp that protects cables and pipes on the outside of the tank, broke off as a result of a routine, but possibly improper, repair during processing, NASA said.

For now, Atlantis waits at the Kennedy Space Center's cavernous assembly building, attached to a tank that may be unsuitable. Plans to roll out the shuttle to the launch pad have been postponed.

Time is running out for NASA to launch its second post-Columbia mission this year, with just a few days in late September and a few days in November available for flights to the International Space Station.

President Bush has ordered the shuttle fleet to be retired in 2010. It would be replaced with a new space vehicle capable of returning Americans to the moon and taking humans to Mars.

But the space station depends on the shuttle because it is the only spacecraft capable of carrying large components into space. Assembly of the 16-nation project was halted after the Columbia accident and may remain on hold a while longer.

Despite a backlog of station components awaiting launch, NASA chief Michael Griffin said the agency will not be rushed.

"We're going to go when we're ready," he said.


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