NASA STS-134 Report #21 11 a.m. CDT Thursday, May 26, 2011
Mission Control Center, Houston, Texas
HOUSTON – Endeavour crew members spent much of their day on late inspection of the shuttle’s thermal protection system and preparations for the fourth and final spacewalk of their visit to the International Space Station.
Pilot Greg Johnson and Mission Specialists Mike Fincke and Andrew Feustel used the shuttle arm with the 50-foot orbiter boom sensor system to survey the right wing. Mission Specialist Roberto Vittori, Feustel and Greg Chamitoff looked at the shuttle’s nose cap. Johnson, Vittori and Chamitoff wound up the survey with inspection of the left wing, completed at 1:16 a.m. CDT.
The images from the inspection were sent to the ground for examination by experts. Because the boom will be left on the space station, the inspection was done while the shuttle was still docked. The 50-foot boom will be available as an extension of the station’s Canadarm2.
Fincke and Chamitoff will do the spacewalk, scheduled to begin about 11:45 p.m. Thursday. Feustel, who participated in the first three spacewalks, helped prepare spacesuits and configure tools. He will be intravehicular officer for the spacewalk.
The entire crew gathered for an hour-long spacewalk procedure review at the end of their workday. Fincke and Chamitoff will spend the night in a reduced-pressure Quest airlock campout to reduce the nitrogen content of their blood.
The in-suit light exercise protocol, successfully used for the same purpose before the third spacewalk, is not being employed for the fourth, because it requires greater use of carbon-dioxide-removing lithium hydroxide canisters. The carbon dioxide sensor in Chamitoff’s suit failed during the first spacewalk. Continuing with the campout is a conservative approach, giving spacewalkers an additional 40 minutes of carbon dioxide scrubbing capability, and was part of the pre-flight plan to prepare for the last spacewalk.
Spacewalk objectives include stowing the boom on the station truss and replacing an electrical flight grapple fixture on one end with a power and data grapple fixture, working on a spare arm for Dextre, the Canadian Special Purpose Dexterous Manipulator, and completing hookup of the new Canadarm2 base on the Zarya module.
At about 10 p.m. Wednesday Kelly talked with representatives of four Tucson, Ariz., television stations. A little after 4:40 a.m. the shuttle and station crews held the traditional joint news conference.
The next status report will be issued after crew wakeup or earlier if warranted.
