Astronauts restart computer; Obama to call Atlantis today
BY WILLIAM HARWOOD
STORY WRITTEN FOR CBS NEWS "SPACE PLACE" & USED WITH PERMISSION
Posted: July 15, 2011
Atlantis commander Christopher Ferguson and pilot Douglas Hurley carried out troubleshooting procedures early Friday and successfully restarted a shuttle flight computer that failed Thursday. But it is not yet clear what caused the initial failure and given the critical nature of the machines, flight controllers planned to carefully monitor general purpose computer No. 4 to make sure it was, in fact, running normally.
While Ferguson and Hurley focused on computer troubleshooting, the rest of the shuttle-station crew pressed ahead with a full slate of work to transfer supplies, equipment and other hardware to and from the International Space Station. The astronauts planned to take a break later in the morning, holding a traditional in-flight news conference at 9:24 a.m. EDT (GMT-4), and taking a call from President Barack Obama at 12:29 p.m.
The Atlantis astronauts are halfway through the 135th and final shuttle mission. Ferguson said the crew has been focused on the tasks at hand, but the reality of the looming end of shuttle operations is beginning to sink in.
"Of course, we've got a busy timeline and there's not a whole lot of time to think about it, but we realize as we go from module to module here, I mean literally we've reached the point where we're saying OK, it's the last train out of town, is there anything else that needs to go back to the Kennedy Space Center, back to Houston before the shuttle program wraps up here?
"And when you say things like that, I think the reality of it really begins to sink in, this is really the last train out of town. Of course, we're going to stay focused and very busy up until we undock, but you know, it's beginning to sink in. I don't think the full magnitude of everything is really going to hit us until after the wheels stop (on the runway)."
With thousands of shuttle workers facing layoffs, the mood at NASA field centers is somber at best, not so much because the shuttle program is ending but because funding was not provided to jump start development of follow-on spacecraft and missions.
As it now stands, it will be several years at best before U.S. rockets and new manned spacecraft are available to launch American astronauts. Until then, NASA will be forced to buy seats on Russian Soyuz spacecraft to get U.S. astronauts to and from the International Space Station.
But Ferguson is optimistic, looking forward to a new era of commercial spaceflight and eventual deep space missions using new NASA spacecraft and heavy-lift rockets that are little more than drawing-board concepts right now.
"Everybody realizes, the shuttle program, everything they've worked on for the last 30 years is coming to a close but by and large, we have something right behind it," he said. "And I think once we can finally get over the fact that the shuttle is gone and its day has come, I believe we'll begin to pick up the pieces and everyone will see that we really do have some vibrant programs out there that we're working on. So I know it's tough, it's kind of one of those wake-type things, you have to come to terms with the end before you can really put on a new beginning."
The glitch with general purpose computer No. 4 is the only significant technical problem encountered by Atlantis' crew since blastoff last Friday.
The shuttle is equipped with five IBM AP-101 general purpose computers. Four of them run identical software while the fifth, tied to a different electrical bus, runs programming from a different vendor to protect against bugs that might take down the four machines in the "redundant set." The shuttle can fly with just two operational GPCs, assuming no generic problems.
During normal orbital operations, two of the redundant computers are typically in stand-by mode while one of the operational machines runs systems management software. That was the machine that failed Thursday, triggering an alarm that woke the crew.
Ferguson loaded the management software into GPC-2 and then went back to bed, leaving the shuttle under the control of GPCs 1 and 2 with GPC-3 in standby mode, ready for use if needed. Early Friday, he re-loaded GPC-4's software from a mass memory unit.
"And the data processing systems officer here in mission control reports that GPC-4 is now up and running in the common set," NASA commentator Rob Navias reported after an initial program load, or IPL, was carried out. "It appears, at least, that the recovery procedure has proven successful. If this computer remains up and running, it will be considered a transient failure and likely will be placed in a standby mode.
"The flight control team will watch the operation of this GPC for some period of time, but based on the way the procedures dictate, this GPC, although at the moment operable once again, would be considered a transient failure."
A transient glitch is defined as a single failure in a computer that subsequently responded normally to an initial program load, or IPL.
"A GPC failure is generally thought to be caused by hardware failures more than software problems," according to NASA's data processing system flight rules. "Even if the failed GPC recovers by doing an IPL, there is concern that the GPC will fail again. If dump analysis can confirm a software-induced failure, the GPC will be considered recovered."
With GPC-4 back up and running, flight controllers will carry out a detailed assessment of its performance to better understand what went wrong in the first place and to determine whether the computer can be relied on to operate normally.
Here is an updated timeline of the crew's planned activities for flight day eight (in EDT and mission elapsed time; includes revision I of the NASA television schedule; best viewed with fixed-width font):
DATE/EDT...DD...HH...MM...SS...EVENT 07/15 12:59 AM...06...13...30...00...Crew wakeup 02:04 AM...06...14...35...00...ISS daily planning conference 02:39 AM...06...15...10...00...MPLM transfers resume 03:49 AM...06...16...20...00...Spacesuit checkout 05:34 AM...06...18...05...00...Spacesuit resizing 06:44 AM...06...19...15...00...CBS Radio/KYW-TV/AP crew interviews 07:04 AM...06...19...35...00...MPLM transfers resume 08:04 AM...06...20...35...00...WPVI-TV/KYW Radio/Reuter crew interviews 08:24 AM...06...20...55...00...Joint crew meal 09:24 AM...06...21...55...00...Crew news conference 10:09 AM...06...22...40...00...Crew photo 10:29 AM...06...23...00...00...MPLM transfers resume 10:45 AM...06...23...16...00...Mission status briefing on NASA TV 12:29 PM...07...01...00...00...Presidential phone call to crew 12:49 PM...07...01...20...00...ISS daily planning conference 01:04 PM...07...01...35...00...Transfer tagup 02:00 PM...07...02...31...00...VIP phone call replay on NASA TV 02:30 PM...07...03...01...00...Interpreted replay of crew conference 02:59 PM...07...03...30...00...ISS crew sleep begins 03:29 PM...07...04...00...00...STS crew sleep begins 03:30 PM...07...04...01...00...VIP phone call replay on NASA TV 05:00 PM...07...05...31...00...Flight day 8 highlights on NASA TV 11:29 PM...07...12...00...00...Crew wakeup 11:45 PM...07...12...16...00...Flight director update on NASA TV
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