Crew installing spare parts platform outside the station
BY WILLIAM HARWOOD
STORY WRITTEN FOR CBS NEWS "SPACE PLACE" & USED WITH PERMISSION
Posted: August 14, 2007
The Endeavour astronauts are working to robotically install a 7,000-pound equipment storage platform on the international space station today, a complex procedure requiring tight choreography between the shuttle and station robot arms.
Educator-astronaut Barbara Morgan, assisted by Tracy Caldwell, used Endeavour's 50-foot-long robot arm to lock onto a grapple fixture on External Storage Platform No. 3 around 9:13 a.m. She began slowly pulling the platform from its perch in the orbiter's cargo bay a half hour later. Shuttle pilot Charles Hobaugh, operating the station's arm from a work station inside the Destiny laboratory module, was standing by to latch onto ESP-3 for the actual installation on the left side of the station's solar power truss.
"This is the first ESP (equipment storage platform) that is being installed only by robotics," said station flight director Heather Rarick. "Station-wide, this is the first major element that's been brought up and installed this way. So it's a new moment for us here in using the robotic arms. And of course, it will take both robotic arms to do this.
"It is a challenge because there is the choreography of handing the piece of equipment from one arm to the next and then getting it into the correct location, the attach system on the truss where it needs to live permanently. There are also heaters and electrical power ... for equipment that is located on this platform. This platform holds spare equipment for us so that in the future we don't have to rely on another vehicle reaching the space station to make any repairs."
This afternoon, Morgan and Caldwell, who is celebrating her 38th birthday in space today, will participate in a series of media interviews starting around 2 p.m. This will be teacher-turned-astronaut Morgan's first opportunity to answer questions from reporters about her experiences in space since Endeavour's launching last Wednesday. Later today, around 5:09 p.m., Morgan plans to participate in the first of three educational events planned for the mission.
Here is an updated timeline of today's activity in space (in EDT and mission elapsed time; ESP-3 installation in progress and times out of date):
EDT............DD...HH...MM...EVENT 08/14/07 Tue 06:37 AM...05...12...00...STS/ISS crew wakeup Tue 08:17 AM...05...13...40...Shuttle arm (SRMS) grapples ESP-3 Tue 08:22 AM...05...13...45...BOK-3 Russian computer replace/testing Tue 08:32 AM...05...13...55...SRMS ESP-3 unberthing Tue 09:02 AM...05...14...25...SRMS ESP-3 handoff Tue 09:42 AM...05...15...05...Station arm (SSRMS) ESP-3 grapple Tue 09:57 AM...05...15...20...SRMS ungrapples ESP-3 Tue 09:57 AM...05...15...20...EVA-3: Tools configured Tue 10:12 AM...05...15...35...SSRMS maneuvers ESP-3 to install position Tue 11:12 AM...05...16...35...ESP-3 installation Tue 11:57 AM...05...17...20...SSRMS ungrapples ESP-3 Tue 11:57 AM...05...17...20...Spacesuit swap Tue 12:12 PM...05...17...35...SSRMS WS4 configured for translation Tue 12:27 PM...05...17...50...Equipment lock preps Tue 12:32 PM...05...17...55...Crew meals begin Tue 01:57 PM...05...19...20...EVA-3: Tools configured Tue 02:01 PM...05...19...25...U.S. network interviews with Morgan, Caldwell Tue 03:22 PM...05...20...45...OBSS OSE EVA-4 prep Tue 04:22 PM...05...21...45...Lab window pane replacement Tue 05:09 PM...05...22...33...PAO educational event Tue 05:30 PM...05...22...54...Mission status briefing on NASA TV Tue 06:22 PM...05...23...45...EVA-3: Procedures review Tue 08:32 PM...06...01...55...EVA-3: Mask pre-breathe Tue 09:17 PM...06...02...40...EVA-3: Airlock depress to 10.2 psi Tue 09:37 PM...06...03...00...ISS crew sleep begins Tue 10:07 PM...06...03...30...STS crew sleep begins Tue 11:00 PM...06...04...24...Daily video highlights reel on NASA TV
At the Johnson Space Center in Houston, meanwhile, engineers are pressing ahead with testing and contingency planning to deal with a small gouge in the shuttle's heat shield tiles. A decision on whether to order a spacewalk repair is expected later this week, after a series of tests to assess what sort of damage, if any, the shuttle's fuselage might experience during re-entry.
John Shannon, chairman of NASA's Mission Management Team, said Monday the damage is not believed to pose a catastrophic threat to the shuttle or its crew and if some other emergency forced a speedy return to Earth, Endeavour could safely land as is.
"We're not talking about catastrophic damage," Shannon said. "But if I have to pull off five or six tiles (after landing) and put a doubler on some structure, replace a rib or anything like that, that's going to increase my turnaround time between (flights) and I'd like to avoid that if possible, if I have an EVA that I think is easy to execute. Now all of that assumes we come back and show that we would have localized heating that could cause some damage underneath and we haven't done that yet."
The testing will determine whether a spacewalk is needed.
"If you ask me whether I think it will or not, I'd probably lean toward it's not going to be absolutely required to do," he said. "The initial simplified cavity model that they ran today passed with no structural damage, no reduction of structural margins at all. But again, it's a simplified model. Since the flow is a little tricky, we want to make sure that we get it exactly right and we'll run that, make sure we understand it and if we don't have to do anything, well we had good practice in pulling together these procedures. And if we do have to do it, I feel fully confident we could execute that with a minimal impact to the mission."
To protect against the possibility of a spacewalk, a team of engineers and astronauts is assessing various repair options. The astronauts are trained for three different types of repair, ranging from the application of a black paint-like material and/or the injection of a thick putty-like insulator to a large carbon composite panel that could be screwed into surrounding tiles to form a thermal barrier. Late Monday, engineers ruled out the latter option because of the small size of the gouge and the complexity of the panel installation procedure.
The Endeavour astronauts plan to carry out space station assembly spacewalks Wednesday and Friday. The Friday EVA involves relatively low-priority get-ahead work and mission managers could opt to substitute a tile repair spacewalk instead. Another option would be to extend Endeavour's mission an additional few days and stage a fifth spacewalk. But no final decisions will be made until testing is complete.