Image above: Endeavour's robotic arm is moved into position for Sunday's focused inspection. Image: NASA TV

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Managers add three days to shuttle mission

Mission managers decided Sunday to extend the STS-118 mission by three days. The decision came after the successful operation of the new Station-to-Shuttle Power Transfer System (SSPTS).

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 that is scheduled to take place August 17.

The SSPTS reroutes power from the space station to the shuttle during docked operations, allowing the orbiter to conserve materials needed to generate power and spend more time in space.

Crew concludes heat shield inspection and prepare for next spacewalk

The STS-118 crew completed today’s focused inspection of Space Shuttle 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 Aug. 8.

STS-118 Mission Specialists Tracy Caldwell and Barbara Morgan, KD5VNP, and Commander Scott Kelly operated the shuttle’s robotic arm. STS-118 Pilot Charles Hobaugh and Expedition 15 Flight Engineer Clay Anderson, KD5PLA,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.

Astronaut Richard A. (Rick) Mastracchio, KC5ZTE

Mission Specialists Dave Williams and Rick Mastracchio, KC5ZTE, are preparing for their second spacewalk. The preparations include spacesuit and tool checkouts.
Later today, the crew members will review the excursion’s timeline before the spacewalkers begin the overnight campout in the station’s Quest Airlock.

The spacewalk is scheduled to begin at 11:31 a.m. 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.