Twenty months after the Columbia tragedy, NASA is still struggling to overcome serious engineering hurdles to resume flying its space shuttles in March, a task that has become even tougher because of hurricane-caused work stoppages and damage to critical facilities.
NASA spokesman Allard Beutel said the Kennedy Space Center stopped work at 6 a.m. Friday and would be closed today while a 200-member damage assessment team inspects the facility.
A bulldozer sits atop debris from the Kennedy Space Center's Vehicle Assembly Building at Cape Canaveral, where hurricanes Frances and Jeanne tore panels from the building.
(Peter Cosgrove -- AP)
Beutel said the team remained hunkered down at Cape Canaveral yesterday while residual wind gusts from Hurricane Jeanne whipped through the complex.
Beutel said a preliminary look around suggested that the three remaining shuttles, closed up and protected with sand bags in anticipation of the storm, "are all okay."
But the center's famous Vehicle Assembly Building, which lost 850 side panels during Hurricane Frances earlier in the month, had more panels torn away by Jeanne late Saturday.
Top NASA officials will meet in about two weeks to assess the progress on crucial shuttle modifications in light of the hurricane-caused delays. They will then decide whether space shuttle Discovery's projected March 16 launch can go forward. The next launch window will not open until early May.
Before flights resume, NASA Administrator Sean O'Keefe has insisted that the agency fully comply with 15 recommendations made by the Columbia Accident Investigation Board last year. As of mid-September, NASA had "conditionally closed" five, but it hopes to finish all of them by year's end.
Whether this will happen remains uncertain, and neither NASA nor the agency's Return to Flight Task Group, a panel of experts charged with monitoring progress on compliance, is radiating optimism -- perhaps in keeping with O'Keefe's often-expressed assertion that the shuttles' return to flight will be "milestone-driven" rather than "schedule-driven."
"We believe that NASA has made significant progress in many areas," retired Lt. Gen. Thomas P. Stafford, co-chairman of the task group, said at a Sept. 8 Senate hearing. "At the same time, we believe that the agency continues to face significant challenges and has considerable work ahead of it in some areas before it will be ready to return the shuttle to flight."
Most of the critical return-to-flight recommendations derive from the need to cope with the tendency of the external fuel tank, filled with liquid oxygen and hydrogen, to shed pieces of foam insulation during launch. Investigators concluded that a foam-caused gouge in the "reinforced carbon-carbon" heat-shielding on the leading edge of Columbia's left wing led to the orbiter's disintegration during reentry on Feb. 1, 2003.
NASA has adopted a series of fallbacks to deal with the problem, based on the reality that engineers will never be able to eliminate foam-shedding entirely. The agency focused first on reducing the size and number of debris fragments, then on developing inspection and onboard repair capabilities and, as a last resort, on using the international space station as a "safe haven" where a shuttle crew could wait for a rescue flight if the shuttle was disabled.
Joseph Cuzzupoli, leader of the task group's technical panel, responding to questions by e-mail, said that he did not see any "technical show-stoppers" that would permanently ground the shuttle but that "there is still a significant amount of work ahead for NASA" in areas relating to the external tank.
At NASA's Marshall Space Flight Center in Huntsville, Ala., engineers have removed large foam "ramps" from the V-shaped strut that links the external tank to the orbiter and installed a heater to keep ice from forming. It was a piece of bipod foam that caused the critical damage to Columbia.
Marshall engineers have also developed new techniques for applying foam manually to other parts of the tank. In all cases the wish is to minimize small "voids" in the foam shielding where ice can form and subsequently pop out the insulation during a high-stress launch.