Endeavour Cleared for Launch

After a week of grueling, nonstop work, NASA cleared space shuttle Endeavour for a Friday liftoff and declared the ship’s damaged robot arm safe to fly.

The decision came late Wednesday, less than 24 hours after the countdown clocks began ticking.

Mission Control quickly relayed the good news to the three residents of the international space station. They have been on board since June, and Endeavour is their ride home.

Shuttle program manager Ron Dittemore said no further testing is required for Endeavour’s robot arm, which is used during space station construction. He also expressed confidence that a leaking oxygen line aboard Endeavour is fixed.

“It has been a tremendous effort over the last week to get to this point,” Dittemore said.

Endeavour’s 50-foot robot arm was bruised Nov. 12 when workers knocked a platform into it. They were in the payload bay to find and repair an oxygen leak that forced NASA to call off a launch attempt the day before.

The platform tore through the thermal blanket covering the arm and an outer honeycomb layer, and left a 2-inch-square bruise on the actual carbon composite structure. NASA conducted ultrasound tests on the area and asked the Canadian company that built the arm to re-create the damage on an arm replica and gauge its strength.