After about a 45-minute delay in the airlock due to a depressurization pump power problem, Tanner and Piper began the spacewalk at 5 a.m. CDT. They completed the excursion at 11:42 a.m. CDT.
In addition to their work with the radiator, Tanner and Piper also replaced an S-Band radio antenna. The antenna, which provides backup communication between the space station and the ground, will be needed during the next mission. That flight, set for December, will require a complicated power down of the station to bring the new power systems on line.
They finished a couple of tasks that will reduce the workload for future spacewalkers, including installing insulation for another communications antenna. Tanner took photos of the shuttle’s wings using an infrared camera to test the camera's ability to detect damage.
The STS-115 crew - Commander Brent Jett, Pilot Chris Ferguson and Mission Specialists Dan Burbank, Tanner, Piper and Steve MacLean - is in its fourth day of joint operations with the station crew.
The astronauts will get time off for part of the day tomorrow before transferring the last of the cargo between the shuttle and the space station. Atlantis will undock from the station at 7:50 a.m. CDT Sunday, circling the orbiting complex once as it departs.