Complete Inspection Of Possible Heat Shield Damage

Mission managers decided Sunday to extend the STS-118 mission of the space shuttle Endeavour by three days. The decision came after the successful operation of the new Station-to-Shuttle Power Transfer System (SSPTS), which allows the orbiter to draw power from the International Space Station, saving its own batteries.

Endeavour is now scheduled to undock from the International Space Station on August 20, and land August 22. In addition to the extra time at the orbital outpost, managers added a fourth spacewalk -- scheduled to take place Friday.

NASA tells ANN the crew completed Sunday’s focused inspection of Endeavour's heat shield and has turned its attention to Monday’s spacewalk. Using the shuttle robotic arm and 50-foot-long Orbiter Boom Sensor System (OBSS), the crew collected imagery of five areas on Endeavour’s underside that may have been damaged during the climb to orbit on August 8.

STS-118 Mission Specialists Tracy Caldwell and Barbara Morgan and Commander Scott Kelly operated the shuttle’s robotic arm. STS-118 Pilot Charles Hobaugh and Expedition 15 Flight Engineer Clay Anderson were at the controls of the International Space Station’s robotic arm.

The data collected during the inspection will be analyzed by experts and engineers at the Mission Control Center in Houston, to determine whether astronauts may need to repair an apparent "gouge" near the shuttle's right maingear door. Mission management team leader John Shannon told Reuters the damage would have to be significant for such a repair to be necessary.

"We don't think [the debris impact] went all the way down to the bottom [of the tile]," Shannon said. "If we even have half the tile left, then we're not going to have any issues at all."

Following their first spacewalk Saturday, Mission Specialists Dave Williams and Rick Mastracchio are preparing for their second spacewalk Monday. The preparations include spacesuit and tool checkouts. The crew members will review the excursion’s timeline Sunday before the spacewalkers begin the overnight campout in the station’s Quest Airlock.

The spacewalk is scheduled to begin at 1131 EDT Monday. The primary task is the replacement of a faulty control moment gyro in the station’s Z1 truss. The station has four gyros that are used to control the station’s attitude.

FMI: www.nasa.gov