Technology & Science

NASA deciding whether Endeavour crew needs to repair gouge

NASA could decide Monday if a spacewalk is needed to repair the damage to the belly of the space shuttle Endeavour.

NASA could decideMonday if a spacewalk is needed to repair the damage to the belly of the space shuttle Endeavour.

This NASA image shows a gouge in the underside of a wing on the shuttle Endeavour during a photo survey of the craft on Sunday. ((NASA/Associated Press))

A laser inspection Sunday by Endeavour's astronauts revealed that a nine-centimetre-long gouge the shuttle suffered during its launch last week penetrates all the way through thermal tiles on its belly.

Mission managers expect to decide Monday, or Tuesday at the latest, whether to send astronauts out to patch the damage.

Engineers are trying to determine whether the area can withstand the searing heat of atmospheric re-entry at the end of the flight. Theywill conduct heating tests on similarly damaged samples.

The unevenly shaped gouge, which is slightly more than five centimetres wide, straddles two adjacent tiles and the corner of a third. The inspection, which was carried out on Sunday using the Canadian-made robotic arm Canadarm, showed the damage went through the 2.5-centimetre-thick tiles, exposing the felt material sandwiched between the tiles and the shuttle's aluminum frame.

John Shannon, the head of Endeavour's mission management team, said they'll be using two methods to calculate whether the tile needs to be repaired.

"The first is we'll be able to model it and run our thermal analysis model to understand what the actual heating impact during re-entry would be fordamageof this type,"Shannon said.

"The second is, we have already made uptwo-foot bytwo-foot sections of tilethat …mimic the exact same damage on those test articles that simulate re-entry conditions."

If a repair is needed, Canadian astronaut Dave Williams will likely be assigned the job.

Meanwhile, thecrew is also preparing for the mission's second spacewalk, scheduled for 11:30 a.m. ET Monday.

Williams and American astronaut Rick Mastracchio are to remove the gyroscope that failed in October and replace it with one Endeavour carried to the station. The broken gyroscope will be stored at the station so it can be brought back to Earth during a later mission.

On Saturday, Williams and Mastracchio successfully installed a roughly two-tonne beam to the backbone of the space station during a spacewalk of more than six hours.

With files from the Associated Press