WASHINGTON -- NASA officials said Tuesday that they aim to have space shuttle Discovery ready in time for a late February launch -- a move that could end months of waiting for the orbiter's final flight.
Discovery was scheduled to launch in early November, but the flight was postponed after technicians found cracks in support beams that stabilize the shuttle's 15-story external fuel tank.
Since then, technicians have fixed five broken beams. NASA officials said workers at Kennedy Space Center were on track to reinforce most of the remaining 103 beams -- excluding eight that don't need the modification -- in time for a launch as early as Feb. 24.
"It's a real tribute to the team that they were able to stay focused on this problem," said Bill Gerstenmaier, associate administrator for space operations.
The next launch window is supposed to open Feb. 27, but NASA officials said they could possibly fly three days earlier.
A European cargo spacecraft is supposed to launch to the International Space Station in mid-February, and if that flight is on time, then Discovery could launch earlier.
"We were able to come up with a plan that allows us to launch a little earlier," said Mike Suffredini, International Space Station program manager.
The lengthy delay on launching Discovery is in line with the care that NASA has taken with shuttle repairs since the 2003 Columbia accident.
After Columbia broke apart on re-entry, investigators attributed the accident to a piece of foam that damaged one of the wings after falling from the external tank during liftoff. That's why NASA technicians were paying particular attention to Discovery in November when cracks were found on the insulating foam layering the tank.
Those cracks ultimately led workers to find the cracks in the support beams.
John Shannon, space shuttle program manager, attributed the breaks in the beams to an alloy that caused some of the beams to be weaker, as well as so-called "assembly stress" that occurred when they were installed.
If these cracks weren't fixed, Shannon said the external tank could "buckle" -- and possibly come apart -- on liftoff or potentially loosen some of the same foam that ultimately doomed Columbia. "This was a tough problem," he said.
The good news on Discovery, however, was tempered Tuesday by an announcement from United Space Alliance that it plans to lay off about 600 Florida workers in April. These cuts would add to the 1,600 jobs that USA already has cut in Florida to prepare for the end of the shuttle program.
The six-member Discovery crew, led by commander Steven Lindsey, is scheduled to bring spare equipment to the station.
These supplies are critical, as the station must operate without the shuttle's massive payload bay after NASA retires the program this year. Three planned flights remain.
During Tuesday's news conference, NASA leaders also briefly addressed the status of astronaut Mark Kelly, who is married to Gabrielle Giffords, the Arizona congresswoman who remains hospitalized after being shot on Saturday.
Kelly is scheduled to lead the April flight of shuttle Endeavour but remains bedside with his wife. Gerstenmaier said NASA had not made any decisions about Kelly.
"We are going to let Mark decide what he wants to do," Gerstenmaier said, who added that "our hearts and prayers go out to the family."
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