Workers at the Kennedy Space Center on Sunday completed a delicate launch pad repair job on the shuttle Atlantis, which is being prepared for liftoff next week to restart International Space Station construction.
Working mid-air on platforms to reach the top of Atlantis' 60-foot(18-meter)-long payload bay, technicians removed two short bolts that held the main communications antenna in place and installed longer fasteners.
"The bolt change-out is all done. They're just removing all the work platforms," said Kennedy Space Center spokeswoman Tracy Young.
The wrong bolts have been in place since Atlantis was manufactured 25 years ago. Torque tests done before the old bolts were removed showed that the antenna was securely anchored, Young said.
"As a precaution, we changed them out anyway. Better to be safe than sorry," she said.
Incorrectly sized antenna bolts also were found and replaced on shuttles Discovery and Endeavour. Atlantis already had been moved to the launch pad when the error was brought to the attention of NASA managers. Replacing the bolts while the shuttle was in a vertical position at the pad greatly complicated the procedure.
The shuttle's cargo bay is filled with a 35,000-pound (15,750-kg) station power module that holds new solar arrays and a rotary joint so the panels can track the sun. Atlantis is scheduled for liftoff on Aug. 27 on NASA's first construction mission in nearly four years.
Construction on the half-built space station stopped after the 2003 Columbia disaster. Since then, NASA has flown two shuttle missions to test safety upgrades imposed after the fatal accident.
The agency needs to finish building the station before the shuttles, which are the only vehicles suited for the job, are retired in 2010. About 16 more flights are planned.