NASA officials late Thursday night decided that astronauts will not take a spacewalk to repair a gash in tiles on the belly of the space shuttle Endeavour. They say testing shows that the shuttle can return to Earth safely with the gash, which was caused by a piece of foam that broke off the shuttle's fuel tank on liftoff.
After meeting for five hours, mission managers opted Thursday night against any risky spacewalk repairs, after receiving the results of one final thermal test. The massive amount of data indicated Endeavour would suffer no serious structural damage during next week's re-entry.
Their worry was not that Endeavour might be destroyed and its seven astronauts killed — the gouge is too small to be catastrophic. They were concerned that the heat of re-entry could weaken the shuttle's aluminum frame at the damaged spot and result in lengthy postflight repairs.
Endeavour's bottom thermal shielding was pierced by a piece of debris that broke off the external fuel tank shortly after liftoff last week. The debris left a 3 1/2-inch by 2-inch gouge in the thermal tiles. Left completely exposed was a narrow 1-inch strip of the overlying felt fabric, the last barrier before the shuttle's aluminum structure.
The only way to fix the gouge would have been to send two astronauts on a spacewalk with black paint and caulk-like goo, and maneuver them beneath the shuttle on the end of a 100-foot robotic arm and extension boom.
The spacewalk would have created so much added risk that mission managers did not want to attempt it unless absolutely necessary.