Columbia Investigators Tell NASA In-Orbit Repair System Is a Must

NASA must develop an ability to inspect the space shuttle’s thermal protection system and repair any damage while in orbit before astronauts can resume spaceflights, Columbia accident investigators told the space agency Friday.

Until now, NASA has said it was not feasible to fix the delicate tiles and leading edge panels while the shuttle is in orbit. The space agency had investigated such repair systems 20 years ago and abandoned the effort.

NASA acknowledged that the recommendation will not be easy to fulfill, but said it already has begun working on the problem and is optimistic that it can develop the necessary technology. NASA spokesman Allard Buetel said the agency still expects shuttle flights to resume in the next six to nine months.

Investigators also said that NASA’s inability to make in-orbit repairs to the Columbia may have influenced its decision to not seek photographic images of the shuttle to assess whether it was damaged during its January launch. Essentially, the investigators are saying NASA officials may not have wanted to know that the shuttle was crippled, because they could not have done anything about it.

NASA has vigorously denied that contention, which has surfaced a number of times in the five months since the Columbia broke up over Texas and killed the seven astronauts aboard. In the immediate aftermath of the accident, shuttle director Ron Dittemore said that even if NASA had known the shuttle was crippled, there was nothing it could do about it.

NASA has said since that it would have done everything possible to save the astronauts if it had known the shuttle was compromised. Under direction of the Columbia Accident Investigation Board, NASA conducted a study that concluded it would have been possible to have launched a second shuttle to rescue the astronauts.

The Columbia was rammed by a 1.67-pound block of insulation foam that fell off the external tank 82 seconds into the launch. It was the largest piece of debris that had ever hit the shuttle and NASA convened a debris assessment team to determine whether it had caused any damage. Investigators now believe that the foam harmed the delicate leading edge and allowed superheated gases to destroy the shuttle’s left wing as it returned to Earth.

The team urged NASA to ask the Defense Department to take photographs of Columbia with spy satellites. But senior managers, including mission management team leader Linda Ham and shuttle director Dittemore, did not ask for those photographs. The decision has since been explained as a miscommunication within Johnson Space Center.

“During the ... flight and investigation, the lack of repair capability was cited repeatedly, and may have been a factor in decisions made during the ... mission, including the decision not to seek images which might have assisted in the assessment of damage resulting from the foam strike on ascent,” the investigators wrote.

The recommendation gives NASA a difficult technical problem.

“We don’t have a solution yet,” Buetel said. “This is a very challenging thing for us, but our engineers are optimistic.”

The board wants NASA to develop the inspection-and-repair capability for all types of flights, including those that will go to the international space station and those that will go into orbits too far to rendezvous with the space station.

Buetel said that when the shuttle visits the space station, astronauts will be able to use the station’s robotic arm to inspect the orbiter. The space station would also provide a work platform to make repairs, though the materials that could be applied in space are still unknown.

The more difficult problem would involve missions that do not go to the space station. In those cases, astronauts could use the shuttle’s own robotic arm. The arm is long enough to inspect the right and left wings’ leading edge, but not the rear of the right wing. “This is obviously not good enough,” Buetel said. Engineers are working on the problem.

NASA is trying to determine whether inspections and repairs would be performed robotically or by astronauts on spacewalks. Until now, astronauts never ventured out of the shuttle’s cargo bay on spacewalks.

“That was then. We are in a different direction now,” Buetel said.