NASA Bumps Shuttle Flight to Next Year
Fri Feb 20,12:26 PM ET
By MARCIA DUNN, AP Aerospace Writer
CAPE CANAVERAL, Fla. - Space shuttles will not fly again until next year, and when one does lift off on the first post-Columbia mission, another will be on standby for a potential rescue mission.
NASA (news - web sites)'s senior spaceflight officials decided Thursday to push back the next launch to March 2005 because of lingering work and engineering concerns, and picked Discovery to be first up. Atlantis will serve as a rescue craft, if needed.
The space agency had been aiming for a fall 2004 launch.
"We said, 'Stop. Let's go ahead and extend the schedule, and let's figure out what the right way is to go about" meeting the recommendations of the Columbia accident investigators, NASA Administrator Sean O'Keefe said. "We're not going to be driven by the calendar. This is going to be a milestone-driven event."
The space agency is struggling to come up with shuttle wing repair kits and inspection booms for astronauts in orbit. Engineers also are still trying to figure out how to keep the fuel-tank foam insulation from breaking off, as a section did during Columbia's doomed flight, and dealing with corrosion in the rudder speed brakes.
Through extensive testing since the Columbia disaster one year ago, NASA has discovered that liquefied air or nitrogen probably seeped into a crack or void in the foam and, upon expanding, blew off a big chunk of the insulation, NASA spaceflight chief Bill Readdy said Friday.
Rather than peeling or flaking off, the foam was pushed off with considerable force, Readdy said. A tank redesign should solve this problem, which the space agency has now identified as the root cause of Columbia's destruction during re-entry.
In addition, faulty application of the foam probably created air pockets, Readdy said. New techniques will be used for applying the lightweight foam insulation to the external fuel tanks and new nondestructive testing should catch any air pockets that sneak through, he added.
A much newer problem involves the rudder speed brakes.
Minor corrosion was found in one of the actuators for Discovery's rudder speed brake, and the gear teeth were installed backward in another rebuilt unit. As a result, NASA is removing the actuators of all three shuttles for inspection; the work is progressing fastest on Discovery and that is why it will fly first, Readdy said.
Because of the Columbia tragedy, NASA decided last month that all shuttles from now on will be devoted to completing the international space station. That way, the astronauts can inspect and repair their ships at the orbiting outpost and await rescue there if any damage is too grave.
The rescue shuttle will not necessarily be on the launch pad but will be ready to fly to the space station within 45 to 90 days, said shuttle program manager Bill Parsons. That is how long seven additional astronauts could remain aboard the space station before food, oxygen and other supplies ran out.
Readdy said NASA could probably put a rescue mission together in as little as 35 days, if necessary.
This will be the first time the space agency has had a rescue ship waiting in the wings since the days of NASA's first space station, Skylab, in the 1970s.
In the case of Columbia, a rescue would have been impossible. The shuttle did not visit the space station; it was in a different orbit than the station and lacked the fuel to get there.
The shuttle fleet has been grounded and space station construction on hold since Columbia shattered over Texas on Feb. 1, 2003.
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