Scott Parazynski and Doug Wheelock left the space station at 4:45 a.m. to begin what would be a 7 hour, 8 minute excursion to complete all of their scheduled tasks and a few get-ahead items for future spacewalks.
They were able to install the port 6 – or P6 – truss segment with its set of solar arrays to its permanent home and install a spare main bus switching unit on a stowage platform for future use if needed.
Additionally, Parazynski took a look at the port Solar Alpha Rotary Joint to gather comparison data for the starboard rotary joint, which has been experiencing increased friction over the past month and a half. Parazynski described the joint as being “pristine,” unlike its starboard counterpart, which was found to have some debris inside the joint during a similar inspection on the mission’s second space walk.
As the spacewalk ended, the P6 solar arrays were deployed with one experiencing a tear in a blanket as it reached the 80 percent deployed point. The crew immediately halted the deploy as engineers in Mission Control began a detailed forensics analysis to determine what the next steps would entail.
The current configuration is safe and there is no urgency to solve the problem immediately allowing station managers and engineers plenty of time to understand the problem before taking any action. The other half of the array deployed perfectly with no issues.
Space Station Program Manager Mike Suffredini said the array is currently producing almost as much power as it would be expected to if fully unfurled – just 3 percent less than normal.
“This will take time and needs to be worked,” Suffredini said. “But my personal opinion is we’ve got the time to work this issue, so we can be methodical about it. And we will.”
After reentering the station, Wheelock noticed a small hole in the outer layer of his right glove thumb. Further analysis will dictate the options as he prepares to join Parazynski on the fourth spacewalk Thursday.
The crew is scheduled to spend Wednesday transferring cargo from the shuttle to the station and preparing for the mission’s fourth spacewalk. They will also participate in a news conference, scheduled for 6:48 a.m.