STS-100 MISSION ARCHIVE Updated: 05/01/01 Space Station Assembly Mission 6A: Space station robot arm By William Harwood CBS News/Kennedy Space Center The following copy originally was posted on the Current Mission space page at http://cbsnews.cbs.com/network/news/space/index.html. Comments, suggestions and corrections welcome! TABLE OF CONTENTS Shuttle countdown set to begin Monday (04/13/01) STS-100 mission preview (04/16/01) Countdown begins for 104th shuttle mission (04/16/01) Shuttle countdown ticks smoothly toward Thursday launch (04/17/01) Endeavour thunders into orbit (04/19/01) Astronauts ready shuttle for docking (04/20/01) Shuttle glides to flawless station docking (04/21/01) Canadarm 2 installed on space station (04/22/01) SSRMS passes initial tests; Raffaello berthed to ISS (04/23/01) Robot arm wired up after problem resolved (04/24/01) Space station computers drop off line (04/25/01) Shuttle flight extended one day; computer woes worsen (04/26/01) Tito cleared for launch in last-minute compromise (04/27/01) Tito blasts off; computer picture improves (04/28/01) Endeavour undocks from space station (04/29/01) Tito, Soyuz TM-32 dock with station (04/30/01) Endeavour lands in California (05/01/01) =================================================================== Shuttle countdown set to begin Monday (04/13/01) The shuttle Endeavour's countdown begins Monday at 6 p.m. for a launch attempt at 2:40:41 p.m. on Thursday, April 19. The shuttle's seven-man crew is scheduled to arrive at the Kennedy Space Center at 10:30 a.m. to begin final preparations. The goal of the 104th shuttle mission is to deliver a multidextrous Canadian-built robot arm to the international space station, along with several tons of supplies, equipment and experiment racks in a new Italian-built cargo module. The STS-100 countdown timeline, ascent events summary and flight plan are posted below. Extensive mission coverage will begin with crew arrival Monday. =================================================================== STS-100 mission preview (04/16/01) 11:25 a.m., 04/16/01, Update: Endeavour poised to carry robot arm to space station Editor's Note... The following story also is posted on the Spaceflight Now web site. By WILLIAM HARWOOD The shuttle Endeavour stands poised for blastoff Thursday on the most complex space station assembly flight yet attempted, a two-spacewalk mission to install a $900 million Canadian robot arm able to move around the station's exterior like a 58-foot-long mechanical inchworm. Endeavour's seven-man crew also will deliver six tons of equipment and supplies in a new Italian-built cargo carrier, including two experiment racks bound or the Destiny laboratory module, critical spare parts and a two-month supply of food for the station's full-time crew. But the top priority of the 104th shuttle mission is installation and checkout of the Canadarm 2 space crane, a billion-dollar piece of complex, high-tech hardware that must be checked out and operational for subsequent assembly missions to proceed. "We're going to be delivering on orbit what I consider to be the mechanical cornerstone, if you will, of the international space station," said spacewalker Scott Parazynski. "It's going to support all the assembly activities from here through the life of the station." The spacewalks and the assembly and checkout of the space station remote manipulator system, or SSRMS, "really usher in a whole new level of integrated operations," said lead flight director Phil Engelauf. The shuttle crew will be operating Endeavour's Canadian-built robot arm at the same time the station crew is putting the new SSRMS through its paces. Adding to the complexity, shuttle and space station flight controllers will be simultaneously commanding both vehicles. That level of coordination has really "made this a very, very complex mission to choreograph, to train for and to have all of our procedures in place," Engelauf said. "It's taken a great deal of work to get there and it really redefines integrated operations for us." Endeavour is scheduled for launch from pad 39A at the Kennedy Space Center at 2:40:41 p.m. Thursday. Strapped in on the shuttle's flight deck will be commander Kent Rominger, pilot Jeffrey Ashby, flight engineer John Phillips and Canadian astronaut Chris Hadfield. Seated below on Endeavour's lower deck will be Parazynski, Italian Umberto Guidoni and Russian cosmonaut Yuri Lonchakov. Phillips and Lonchakov are both rookies while their crewmates are all shuttle veterans. Endeavour's liftoff is timed to coincide with the moment Earth's rotation carries the launch pad into the plane of the international space station's orbit. To catch up with its quarry, the shuttle will climb into an initially elliptical orbit with a perigee, or low point, of just 98 statute miles and an apogee, or high point, of 204 miles, slightly lower than the space station. A series of rocket firings over the next two days will fine-tune Endeavour's approach, setting up a docking Saturday morning. As with the most recent shuttle visit in March, the flight plan calls for Rominger to approach the station from behind and below, looping up directly in front of the outpost before beginning the final push to dock. Flying tail down with its cargo bay facing the station, Rominger will manually guide Endeavour to a linkup with a docking port known as PMA-2 on the forward end of the new Destiny laboratory module. But the crew will not actually enter the station for the first time until after a spacewalk Sunday by Hadfield and Parazynski to install the new robot arm on the hull of the Destiny module. The station currently is made up of four pressurized modules connected end to end. NASA's Destiny module is bolted to the multi-hatch Unity node. Unity, in turn, is connected to the Russian-built NASA-financed Zarya module, which is attached to the Russian Zvezda command module. Unity's port hatch is occupied by a spare shuttle docking port while its starboard hatch is vacant. Unity's upward-facing port is occupied by a boxy structural truss that houses the station's four stabilizing gyroscopes. Bolted to the top of the Z1 truss is the huge P6 solar array, which provides most of the station's electrical power. The two panels making up the P6 array stretch 240 feet from tip to tip, oriented like two huge wings extending to either side of the station's central axis. The day before Endeavour's launch, the station's on-board crew - Expedition Two commander Yuri Usachev, Susan Helms and James Voss - will strap into a Russian Soyuz spacecraft docked to a downward-facing port on the Zarya module and fly it around to the Zvezda module's aft port. It is the same Soyuz that carried the station's first full-time crew into orbit Oct. 31 and it is nearing the end of its certified on-orbit lifetime of 180 days. A fresh Soyuz is scheduled for launch April 28 - the day Endeavour undocks - carrying a three-man crew expected to include U.S. millionaire Dennis Tito. The so-called taxi crew will return to Earth May 6 in the old Soyuz, leaving the station crew with a fresh lifeboat good for another six months in space. The new Soyuz will remain docked to the Zarya module's Earth-facing, or nadir, port. A Progress supply ship will dock at Zvezda's aft port late next month. In general, the Russians want to use Zarya's nadir port for Soyuz vehicles to keep Zvezda's docking port free for use by Progress supply ships. Progress vehicles can reboost the station's altitude from the aft port, but not from the Zarya port. Usachev and his crewmates will move the 2R Soyuz before Endeavour's launch primarily to get the work out of the way. All the comings and goings, coupled with work after Endeavour undocks to continue checkout of the station's new robot arm, is one of the major reasons NASA managers have objected so strongly to space tourist Tito's inclusion in the Soyuz taxi crew. Tito reportedly paid the Russians $20 million for the flight. Robert Cabana, manager of international operations for the station program, reiterated NASA's objections last week, saying he believed Tito should put off his visit until the next Soyuz taxi flight in October. That would allow more time for training, eliminate any interference during a very busy time in station assembly and give station managers more time to set up formal procedures and requirements for future space tourists. But Tito and the Russians have been adamament about launching on schedule, regardless of NASA's objections. "For somebody who's had as life long dream of flying in space, to delay for a few months and fly in October and be invited in to be part of the team and to train with us and to really make it a positive experience, I find it a little incredulous that he wasn't willing to accept that," Cabana said. "But that was his position and that's where it ended up." Cabana did not address the larger issue: NASA's apparent inability to prevent a space station partner - Russia - from acting unilaterally over the unanimous opposition of the program's other international partners. For their part, Usachev and his two NASA crewmates have said they will provide a warm welcome for Tito and his crewmates. But that is down the road. For Endeavour's crew, the focus is squarely on docking with the international space station and delivering its high-tech robot arm. The astronauts will not actually enter the station on docking day because the shuttle's cabin air pressure will have been lowered from 14.7 pounds per square inch to 10.2 psi Friday in preparation for the spacewalk Sunday to install the Canadarm 2 space crane. The astronauts will, however, place video and power cables in the PMA-2 docking port that will be recovered later by the station crew for use during the spacewalk Sunday. The SSRMS is bolted to a Spacelab Pallet in Endeavour's cargo bay. Ashby, operating the shuttle's 50-foot-long robot arm, will pick up the pallet early Sunday and attach it to a mounting plate on Destiny's hull. Hadfield and Parazynski then will float out of Endeavour's airlock to begin a planned six-and-a-half-hour spacewalk. The new robot arm will be launched unpowered and the first item on the agenda for Hadfield and Parazynski will be to attach interim power cables. The arm later will receive power and relay telemetry through a so-called power and data grapple fixture, or PDGF, already in place on Destiny's hull. Unlike the shuttle's robot arm, which is attached to the orbiter at one end like a traditional crane, the SSRMS has no dedicated attachment point. Either end can be used to grasp a PDGF and eventually, the arm will be able to make its way from point to point along the station's external framework on its own, moving end over end like an inchworm from one PDGF to another. The new arm measures 58 feet long and weighs some 3,968 pounds. It has seven joints, is capable of rotating through 540 degrees and can move objects massing 255,736 pounds. Force sensors provide feedback to arm operators, giving them what amounts to a sense of touch. "The arm is probably a couple of generations evolved beyond the arm that is part of the space shuttle," Hadfield said during a pre-flight briefing. "The new one has a hand on both ends. Not really a hand, but the equivalent of a hand, the ability to grab and grapple. "That hand not only grabs on, but it also plugs in electrically and connects video and connects data when it grabs on, so the arm can be operated from either end. And the arm can move itself around the station as required so it can far exceed the reach the arm on the shuttle would have." The shuttle's robot arm, by comparison, is a fairly straightforward and well understood piece of hardware, Hadfield said. The new arm is much more capable - and complex. "From a straight flying point of view, they're quite similar," he told reporters. "You rotate it with your right hand with a rotational hand controller and you move it in x, y and z with your other hand. So from an operator's point of view, you really don't move the arm, you fly each of the arms, it becomes an extension of your own body like any good machine. Both of them fly quite elegantly. "But there's a lot more capability in Canadarm 2 in that not only can it grab and plug in, but it has force sensors in it as well so I can feel what it is doing. But with added capability comes added complexity. And the computer interface for it is a two-person operation, one person flying and the other person running the systems. "Because it's a brand new system we are going to be extremely procedural and careful with that arm," Hadfield said. "We're going to move it agonizingly slowly at first, I think, until we get a feel whether or not it behaves like our simulators have predicted." After connecting power cables to the arm, Hadfield and Parazynski will unbolt eight so-called "superbolts" holding the folded space crane to the Spacelab Pallet. "The number one objective during spacewalk number one is to provide power to the arm so it can warm itself up," Hadfield said. 'So the first thing we have to do is hook up the wiring and then once it's warmed up for a little while, we will start undoing these enormous superbolts. "Then with myself riding on the end of the shuttle arm and Scott providing a manual lift and then guidance on the other end, we are going to unfold that arm through 180 degrees and actually bolt it together." Lead spacewalk planner Jeff Patrick said Parazynski, his feet anchored in a foot restraint, "basically does a clean and jerk on the booms, raises the lower booms up so they're about at his head level." The boom joints will be bolted together with fasteners that work like concrete bolts, expanding internally as they are tightened to rigidly lock the arm members together. The arm will be left in that extended position overnight. Hadfield and Parazynski, meanwhile, will remove a new UHF space-to-space radio antenna from the shuttle's cargo bay and mount it near the forward end of the Destiny module before re-entering Endeavour's airlock. With the shuttle's cabin air pressure back up to 14.7 psi, hatches between Endeavour and the station will be opened for the first time early the next morning. The station crew plans to begin tests and checkout of the new robot arm while the shuttle astronauts use Endeavour's robot arm to attach the Italian-built Raffaello cargo carrier to Unity module's nadir port. Raffaello is the second such cargo carrier provided by the Italians. it is loaded with some 7,500 pounds of equipment, experiment racks and supplies, including enough food to last the Expedition Two crew for two full months. The crew will not enter the module until the next day, after its interior has been warmed up. While the Raffaello work is going on, Helms and Hadfield will be putting the new arm through its paces from a robotic work station in the Destiny module. "We'll just basically be moving the joints through some of the range of travel ... and doing a checkout of the primary string and a little bit of the backup string," Engelauf said. "We've prioritized the checkout activities to get the most important things (done first) to ensure we've got a functional arm before we transfer power to the station grapple fixture." The next day, with hatches between Endeavour and the station once again sealed, the Expedition Two crew will enter Raffaello to begin moving supplies and equipment aboard while the shuttle crew stages another spacewalk. The primary goal of the second excursion is to make electrical connections needed to route power to the new robot arm's PDGF. Parazynski, riding on the end of the shuttle's robot arm, will make those connections at a utility panel. "We'll be doing a lot of the re-wiring to basically enable the space station arm to live on the space station permanently," Parazynski said. "We'll go out and with Chris's help, take off a shield on the side of the laboratory module and I'll spend the next hour and a half or so doing some fairly delicate work, surgery almost, rewiring some very delicate fiber optic cables to enable the space station arm to live permanently on the station." Hadfield, meanwhile, will remove a no-longer-needed UHF antenna from Unity's starboard port, where the station's main airlock will be installed during a mission in June, before disconnecting the Spacelab Pallet umbilicals that initially powered the SSRMS. Once the station's arm is powered through the PDGF, Helms will use it to lift the Spacelab Pallet off the lab cradle assembly to make room for Parazynski to mount a 400-pound spare DC power converter on the station's hull. The arm, with the 3,000-pound Spacelab Pallet attached to one end, will be left in an extended position overnight. The shuttle crew, meanwhile, will repressurize Endeavour's cabin to 14.7 psi and re-open hatches to the station. The next day, Helms and Hadfield will continue testing the new arm's capabilities with a so-called "loaded checkout." "This is basically moving the Spacelab Pallet through a series of motions to demonstrate the capability of the arm to operate with an object on the end of it," Engelauf said. "We will hand off the Spacelab Pallet to the shuttle arm during this day. And this is a first time activity, we've not done anything like this in spaceflight history. It will demonstrate a truly integrated operation between the crews and should be quite interesting to watch." After the handoff is complete, Ashby will re-berth the pallet in the shuttle's cargo bay for return to Earth. And while all of that is going on, the combined crews will be continuing work to unload the Raffaello module and to install powered experiments from the shuttle's middeck to the newly installed lab racks in the Destiny module. Because of the sheer complexity of the work planned to this point, Engelauf has included a possible third spacewalk in the crew's flight plan to handle any unfinished business. If the spacewalk is required, it would be carried out on flight day 8, the day after the loaded checkout of the SSRMS. If a third spacewalk is not required, however, the crews will instead focus on continuing to unload Raffaello and carrying out additional tests of the new robot arm. The arm must be fully operational before the next station assembly mission in June to deliver the facility's main airlock. The shuttle arm does not have a long enough reach to mount the airlock on Unity's starboard hatch. "Every one of these flights is related, so we have got to get that arm fully checked out and functional and ready to provide a 'go' for the 7A airlock installation that is planned for the next shuttle mission," said station flight director John Curry. So on flight day eight, the crew will run through what amounts to a dry run of the airlock installation procedure to make sure everything works as expected. "Not everything will be checked out by the end of the shuttle mission, we just prioritize what had to get done for us to say the arm was fully functional and ready to go," Curry said. "After the shuttle has undocked ... we will work what we need to do between the undocking on April 28 and the 7A mission, which is now launching on June. 14. "During that period of time, six weeks or so, we want to completely check out the arm, every system, every string, we've got to do additional camera checkouts, etc. My plan for that period of time is to actually schedule once a week where Jim or Susan can actually do some functional checkouts of the arm and also get some stick time, some crew proficiency time, to operate the arm." The day after the SSRMS dry run on April 26, Raffaello, now loaded with station trash and discarded equipment, will be detached from Unity's nadir port and re-berthed in Endeavour's cargo bay. If all goes well, the shuttle will undock the following day - around 11:45 a.m. EDT on April 28 - filming the station with a large-format IMAX camera before departing for good. Landing is targeted for around 9:35 a.m. on April 30. The Soyuz taxi crew will dock with the station a few hours before Endeavour's landing. Another Progress supply ship will be launched around May 20 and the shuttle Atlantis will deliver the station's airlock in mid June. "Things are going beyond my wildest expectations," said station program manager Tommy Holloway. "I believe this is an unprecedented period of history in human spaceflight in terms of the number of flights we've flown since last year when the service module was launched." It is also a somewhat frustrating time, Holloway said. At least from a public relations standpoint. "I'm very disappointed in the entire public awareness of what's going on 212 miles above the Earth in terms of the magnitude and the challenges, the overall complexity, how well it's been going," he told reporters last week. "It's like we're building the pyramids of Egypt in orbit and nobody's watching." "All you guys want to talk about is what broke last week instead of what is really going on. So yeah, I'm disappointed. I think there's a terrific story out there about what this country and 16 other countries are doing together, building relationships across the world, doing some really incredible, fabulous things and we spend all our time talking about what in the end will be insignificant things." Frustrating or not, "it's a great time to be an astronaut," Hadfield said. "We are in the thick of building space station, which from an astronaut's point of view provides a wealth of challenges and opportunities. It's just a great era for us as we put this thing together." =================================================================== Countdown begins for 104th shuttle mission (04/16/01) 06:30 p.m., 04/16/01, Update: STS-100 countdown begins The shuttle Endeavour's countdown to launch Thursday begin this evening at 6 p.m. There are no technical problems of any significance at pad 39A and forecasters are predicting good weather Thursday. Launch is targeted for 6:40:41 p.m. =================================================================== Shuttle countdown ticks smoothly toward Thursday launch (04/17/01) The shuttle Endeavour's couuntdown is ticking smoothly toward launch Thursday on a high-stakes mission to deliver the international space station's Canadian-built robot arm, a $900 million space crane that can move about the station's hull like an inchworm. NASA test director Pete Nickolenko said today there are no problems of any significance at pad 39A, the shuttle's payload is in good shape and forecasters are predicting a 90 percent chance of acceptable weather during Endeavour's five-minute launch window Thursday. Similar conditions are expected Friday should launch slip 24 hours. The shuttle can reach the space station as long as it takes off within five minutes of the moment the launch pad is within the plane of the station's orbit. To maximize performance, however, NASA will pass up the first five minutes of the theoretical 10-minute window and target liftoff for the moment the pad is "in plane" with the target. Based on the latest radar tracking of the space station, the preferred launch time will be 2:40:41 p.m. Thursday, plus or minus a few seconds. The exact launch time will be updated Thursday. Based on a liftoff Thursday, Endeavour will dock with the station on flight day three, i.e., Saturday morning. Should launch slip to Friday, the crew can still make a flight-day-three rendezvous - on Sunday - but the crew would have to use quite a bit more propellant to do so. That would reduce the amount of altitude reboost the shuttle could provide to the station later in the mission. As of this writing, however, it is still unclear how many launch attempts NASA can make. The Russians are scheduled to launch a fresh Soyuz lifeboat to the station on April 28, the same day Endeavour is scheduled to undock from the station if it takes off Thursday. A Friday launch of Endeavour would force the Russians to delay the Soyuz flight a day. The new Soyuz is needed because the lifeboat currently docked to the station, the same spacecraft that launched the lab's first full time crew on Oct. 31, is nearing the end of its certified 180-day orbital lifetime. The crew of the upcoming Soyuz taxi flight, which is expected to include U.S. millionaire/space tourist Dennis Tito, plans to spend about six days aboard the station before returning to Earth in the old Soyuz, leaving the new Soyuz behind in its place. The Russians have not yet formally agreed to accept any delays in the upcoming April 28 launch of the new Soyuz. NASA managers currently are negotiating with the Russians to ensure more than one launch opportunity for Endeavour, but it's not yet known how those discussions will play out. =================================================================== Shuttle Endeavour thunders into orbit (04/19/01) 09:30 a.m., 04/19/01, Update: Shuttle Endeavour fueled for launch The space shuttle Endeavour has been loaded with a half-million gallons of liquid oxygen and hydrogen rocket fuel in preparation for launch today on a critical space station assembly mission. The weather appears ideal, there are no technical problems at pad 39A and Endeavour is on track for a launch attempt at 2:40:42 p.m. EDT, the moment Earth's rotation carries pad 39A into the plane of the space station's orbit. The exact launch time may change by a few seconds based on final radar tracking of the station. But the window will last just five minutes. Should launch slip to Friday, liftoff would be targeted for 2:18:07 p.m. Here is the remainder of today's countdown: TIME....EVENT 09:25 a.m....Crew photo/TV opportunity 10:15 a.m....Astronauts attend final weather briefing 10:25 a.m....Astronauts suit up for launch 10:46 a.m....Countdown resumes at the T-minus three-hour mark 10:55 a.m....Astronauts depart crew quarters and head for pad 39A 11:25 a.m....Crew begins boarding Endeavour 12:40 p.m....EndeavourŐs hatch is closed for launch 01:26 p.m....Begin a 10-minute hold at T-minus 20 minutes 01:36 p.m....Countdown resumes 01:47 p.m....Begin a 45-minute hold at T-minus nine minutes 02:32 p.m....Countdown resumes at the T-minus nine-minute mark 02:36 p.m....Hydraulic power unit startup 02:41 p.m....Launch 02:49 p.m....Main engine cutoff The goal of the 104th shuttle mission is to deliver a $900 million Canadian-built robot arm that will be able to move about the station like an inchworm to assist in assembly operations and maintenance. The Endeavour astronauts also are carrying some 7,500 pounds of supplies and equipment, including enough food to last the station's crew for two full months and two experiment racks bound for the Destiny laboratory module. A detailed 3,500-word mission preview is available immediately below for readers interested in additional background. 12:30 p.m., 04/19/01, Update: Astronauts strapped in for launch Shuttle Endeavour's seven-man international crew is stapped into the orbiter awaiting liftoff. White room closeout personnel are in the process of sealing the shuttle's side hatch and breaking down equipment in preparation for launch at 2:40:42 p.m. There are no technical problems at pad 39A and the weather appears ideal. 03:30 p.m., 04/19/01, Update: Shuttle Endeavour rockets into orbit on high-stakes robotic mission The space shuttle Endeavour rocketed into orbit today on a tricky, make-or-break flight to install a $900 million Canadian robot arm on the international space station, a high-tech space crane able to creep about the outpost like a mechanical inchworm. Its three main engines roaring at full throttle, Endeavour blasted off from pad 39A on time at 2:40:42 p.m., majestically climbing through a partly cloudy sky and thundering away on a course paralleling the East Coast. Two minutes later, its spent solid-fuel boosters were jettisoned for a parachute descent to waiting downrange recovery ships and Endeavour continued an uneventful climb to space on the power of its three hydrogen-fueled main engines. At the moment of liftoff, Endeavour's quarry was passing over the equator south of India. If all goes well, shuttle commander Kent Rominger will guide the spaceplane to a docking with the international space station around 9:30 a.m. Saturday. Joining Rominger for the 104th shuttle mission are pilot Jeffrey Ashby, flight engineer John Phillips, physician-astronaut Scott Parazynski, European Space Agency astronaut Umberto Guidoni, Canadian astronaut Chris Hadfield and Russian cosmonaut Yuri Lonchakov. The primary goal of the flight is to install the "Canadarm 2," a 57-foot-long multi-joint space crane that is required to be in place and operational before the next assembly mission can be launched in June. The goal of that flight is to attach the station's main airlock to the starboard hatch of the U.S. Unity module. But the shuttle's 50-foot-long arm - also built in Canada - cannot reach far enough to install the airlock. And so the new crane a requirement for assembly to proceed. Parazynski and Hadfield are scheduled to install the the Canadarm 2 during two six-and-a-half-hour spacewalks Sunday and Tuesday. The arm can be anchored to the station at either end, locking onto sockets mounted along the hull that provide power and relay video and telemetry to computer workstations inside the station. Only one such "power and data grapple fixture," or PDGF, is currently in place. But additional sockets will be installed later and eventually, the arm will be able to move about the station end over end, from socket to socket. Increasing its mobility even more, a motorized cart ultimately will be mounted on the station's main truss that will be able to carry the arm out to the facility's huge solar arrays on each end. "As a Canadian, it's just an amazing opportunity for me personally, and as a representative of my country, to be riding on one arm that says 'Canada' and unfolding another arm that says 'Canada' as our prime contribution to the international space station," Hadfield said. Hadfield will assist station astronaut Susan Helms during the arm's initial checkout and activation, using one of two robotic workstations in the Destiny laboratory module. Among her other checkout tasks, Helms will carry out a dry run of the airlock installation procedure next week, putting the arm through the same maneuvers that will be required during the actual installation in June. "The arm is probably a couple of generations evolved beyond the arm that is part of the space shuttle," Hadfield said during a pre-flight briefing. "The new one has a hand on both ends. Not really a hand, but the equivalent of a hand, the ability to grab and grapple. "That hand not only grabs on, but it also plugs in electrically and connects video and connects data when it grabs on, so the arm can be operated from either end. And the arm can move itself around the station as required so it can far exceed the reach the arm on the shuttle would have." The second objective of Endeavour's mission is to deliver 7,500 pounds of equipment and supplies, including two experiment racks and a two-month supply of food for Helms and her two crewmates. The logistics are housed in an Italian-built cargo module named Raffaello. Parazynski, operating Endeavour's robot arm, will unberth the cargo module Monday and attach it to Unity's Earth-facing hatch. It will be unpacked over the next four days and reloaded with station trash and discarded equipment for return to Earth. Endeavour is scheduled to undock from the space station April 28, the same day the Russians plan to launch a new Soyuz spacecraft to replace the station's current emergency lifeboat, which is nearing the end of its certified 180-day orbital lifetime. The crew of this so-called Soyuz taxi flight is expected to include U.S. businessman Dennis Tito, who reportedly paid the Russians some $20 million to become the first space tourist. Tito and his crewmates plan to spend about six days aboard the station before returning to Earth in the Soyuz currently attached to the outpost. NASA managers and the station's other international partners unanimously oppose Tito's visit, arguing his visit should be delayed to October to permit additional training time and to minimize distractions to the station's crew at a particularly busy period in the facility's assembly. But NASA and the other partners appear powerless to stop the Russians, who argue Tito is properly trained and launching on a Russian spacecraft that will dock with a Russian module. Assuming NASA fails in last-minute attempts to persuade the Russians to delay Tito's visit, the American businessman and his two Soyuz crewmates will dock with the international space station on April 30, just a few hours before Endeavour's planned landing. =================================================================== Astronauts ready shuttle for docking (04/20/01) The Endeavour astronauts are working through a quiet day in space today, checking out on-board systems and fine-tuning their approach to the international space station. If all goes well, commander Kent Rominger will guide the shuttle to a docking with the orbital outpost at 9:36 a.m. Saturday. The shuttle's robot arm will be powered up later this morning for a routine payload bay survey. Laser range finders and other rendezvous tools will be set up and the crew cabin will be depressurized from 14.7 psi to 10.2 pi in preparation for a spacewalk Sunday by Scott Parazynski and Canadian astronaut Chris Hadfield. At 2:41 p.m. today, Rominger, Hadfield and flight engineer John Phillips will participate in round-robin interviews with three television stations. A mission status briefing from the Johnson Space Center is on tap at 3:30 p.m. and the astronauts will go to bed at 6:41 p.m. Here is a timeline of today's major activity from revision A of the NASA television schedule: REV..EVENT.................................DD/HH:MM...EDT........GMT 9....ENDEAVOUR CREW WAKE UP................00/13:00...03:41 AM...07:41 11...AIRLOCK PREPARATION...................00/15:15...05:56 AM...09:56 11...SPACESUIT CHECKOUT....................00/15:45...06:26 AM...10:26 12.*.ROBOT ARM POWERUP AND CHECKOUT........00/17:30...08:11 AM...12:11 13.*.PAYLOAD BAY SURVEY....................00/18:30...09:11 AM...13:11 14.*.RENDEZVOUS TOOL CHECKOUT..............00/19:45...10:26 AM...14:26 15...VIDEO FILE (subject to change)...HQ...00/21:19...12:00 PM...16:00 16...CABIN DEPRESS TO 10.2 PSI.............00/23:15...01:56 PM...17:56 16.*.KUSA-TV, KMGH-TV, KCNC-TV......TDRE...01/00:00...02:41 PM...18:41 LIVE INTERVIEWS 17...CENTERLINE CAMERA INSTALLATION........01/00:20...03:01 PM...19:01 17...MISSION STATUS BRIEFING.........JSC...01/00:49...03:30 PM...19:30 17...DOCKING RING EXTENSION................01/00:50...03:31 PM...19:31 18...SPACE STATION PAYLOAD UPDATE...MSFC...01/01:49...04:30 PM...20:30 19...FLIGHT DAY HIGHLIGHTS REEL......JSC...01/03:19...06:00 PM...22:00 19...ENDEAVOUR CREW SLEEP BEGINS...........01/04:00...06:41 PM...22:41 19...CREW REPORT/HIGHLIGHTS REEL.....JSC...01/04:19...07:00 PM...23:00 20...ISS CREW SLEEP BEGINS.................01/05:00...07:41 PM...23:41 The complete TV timeline is available below. An updated summary timeline will be posted as soon as today's Execute Package is available. =================================================================== Shuttle Endeavour glides to flawless station docking (04/21/01) 07:00 a.m., 04/21/01, Update: Endeavour closes in on space station The Endeavour astronauts are closing in on the international space station today for a docking at 9:32 a.m. Just before 6 a.m., commander Kent Rominger spotted the station visually through the shuttle's overhead windows and a few minutes later, the station crew spotted Endeavour at a distance of 41 miles. There are no technical problems of any significance with the shuttle, but engineers are still scratching their heads over the status of a carbon dioxide removal system in the station's Russian command module, Zvezda. The Vozdukh system was only working at half power Friday and the crew planned to troubleshoot the system early today. But a NASA spokesman said engineers reported the device apparently resumed normal, full-power operation on its own today. As of this writing, it's not yet clear what was wrong or what happened to correct the problem. The Vozdukh's performance was not an issue for Endeavour's docking because the shuttle's air scrubber can easily compensate for low output from the Russian system. But flight controllers wanted to fix the problem before arrival of a Soyuz spacecraft April 30 carrying U.S. businessman Dennis Tito and two crewmates. Working at half power, the Vozdukh would not have been able to handle the load of the increased six-member crew, forcing them to tap into their limited supply of lithium hydroxide canisters. While that's not a problem in and of itself, flight controllers naturally want to reserve the lithium hydroxide supply for emergency use only. Assuming the Vozdukh stays healthy, that will not be an issue. Today's flight plan calls for Rominger to approach the station from behind and below, looping up directly in front of the outpost before beginning the final push to dock. The terminal phase of the rendezvous will begin with a rocket firing at 7:18 a.m. with the shuttle trailing its quarry by about nine statute miles. The shuttle should be positioned 600 feet directly below the station at 8:48 a.m. At that point, Rominger will initiate a pitch maneuver as he loops up in front of the station, arriving on the so-called velocity vector 310 feet directly ahead of the outpost at 9:02 a.m. The shuttle will be oriented with its tail facing Earth and its cargo bay facing the station. Rominger will briefly halt Endeavour's approach at a distance of 30 feet or so to ensure communications coverage through NASA's western Tracking and Data Relay System satellite. The final push to dock should begin at 9:26 a.m. for a linkup at 9:32 a.m. The station currently is made up of four pressurized modules connected end to end. NASA's Destiny laboratory module is bolted to the multi-hatch Unity node. Unity, in turn, is connected to the Russian-built NASA-financed Zarya module, which is attached to the Russian Zvezda command module. Unity's port hatch is occupied by a spare shuttle docking port while its starboard hatch is vacant. Unity's upward-facing port is occupied by a boxy structural truss that houses the station's four stabilizing gyroscopes. Bolted to the top of the Z1 truss is the huge P6 solar array, which provides most of the station's electrical power. The two panels making up the P6 array stretch 240 feet from tip to tip, oriented like two huge wings at right angles to the long axis of the station. Endeavour will dock at a pressurized mating adapter - PMA-2 - on the front end of the Destiny module. But the crew will not actually enter the station for the first time until after a spacewalk Sunday by Chris Hadfield and Scott Parazynski to install the new Canadarm 2 space crane on the hull of the Destiny module. To help the spacewalkers purge nitrogen from their bloodstreams, the shuttle's cabin air pressure was lowered from its normal 14.7 pounds per square inch to 10.2 psi Friday. The station's pressure remains at 14.7 psi, precluding the crews from opening hatches between the spacecraft today. Instead, Endeavour's astronauts will limit their activities to PMA-2, opening the docking port tunnel, stowing equipment the station crew needs and then resealing the hatch. The station crew then will enter PMA-2 and retrieve the equipment, using the docking port as an airlock. Here is a detailed timeline for today's rendezvous: Mission Elapsed Time EDT........DD...HH...MM...EVENT 07:00 AM...01...16...19...Sunrise 07:10 AM...01...16...29...ISS Ku comm mode activated 07:15 AM...01...16...34...ISS maneuver to docking attitude 07:18 AM...01...16...37...TI rendezvous burn 07:28 AM...01...16...47...Noon 07:38 AM...01...16...57...ISS in attitude 07:57 AM...01...17...16...Sunset 08:15 AM...01...17...34...ISS P6 solar arrays feathered 08:32 AM...01...17...51...Sunrise 08:35 AM...01...17...54...Mid-course correction burn #4 08:38 AM...01...17...57...Range: 1,500 feet 08:43 AM...01...18...02...Range: 1,000 feet 08:44 AM...01...18...03...Ku-band antenna to low power 08:48 AM...01...18...07...Last time to be in approach ready config 08:48 AM...01...18...07...R-bar arrival at 600 feet below station 08:50 AM...01...18...09...Initiate TORVA maneuver 08:52 AM...01...18...11...Range: 400 feet 09:00 AM...01...18...19...Range: 300 feet 09:00 AM...01...18...19...Noon 09:02 AM...01...18...21...V-bar arrival 310 feet in front of station 09:02 AM...01...18...21...Range: 250 feet 09:04 AM...01...18...23...Last time to be in dock ready config 09:05 AM...01...18...24...Range: 200 feet 09:09 AM...01...18...28...Range: 150 feet 09:13 AM...01...18...32...Range: 100 feet 09:13 AM...01...18...32...Russian ground station AOS 09:19 AM...01...18...38...Range: 50 feet 09:21 AM...01...18...40...Range: 30 feet; start stationkeeping 09:22 AM...01...18...41...TDRS-West acquissition of signal 09:26 AM...01...18...45...End stationkeeping; push to dock 09:28 AM...01...18...47...Russian ground station LOS 09:29 AM...01...18...48...Sunset 09:30 AM...01...18...49...Range: 10 feet 09:32 AM...01...18...51...DOCKING 10:02 AM...01...19...21...TDRS-East acquisition of signal 10:05 AM...01...19...24...Sunrise 10:17 AM...01...19...36...TDRS-West loss of signal 03:00 p.m., 04/21/01, Update: NASA managers pleased with flawless docking Shuttle skipper Kent Rominger guided Endeavour to a glacial docking with the international space station today as the two spacecraft sailed 243 miles above the south Pacific Ocean at five miles per second. The successful linkup sets the stage for a critical spacewalk Sunday by astronauts Scott Parazynski and Canadian Chris Hadfield to install the new Canadarm 2 space crane on the station's hull. "The delivery of the Canadarm is really crucial to mthe remaining assembly of the space station," said lead flight director Phil Engelauf. "We're now at the point in the assembly where the components to be added to the station cannot be installed without the additional reach capability that's provided by this new arm." Starting with the next assembly mission in June. During that flight, the station's main airlock will be installed, a job that cannot be accomplished using the shuttle's shorter robot arm. The airlock will enable station crews to stage assembly and maintenance spacewalks between shuttle visits. The new Canadarm 2, mounted on the Destiny laboratory module, must be checked out and operational before the airlock can be launched. But if today 's docking was any indication, the flight is off to a near perfect start. "Everything went great, we are right on the timeline and looking forward to starting a really aggressive period over the next few days of deploying the Canadarm 2 and transferring the contents of the (Raffaello cargo module) into the station," said Engelauf. "Everything's going great so far." Positioned directly ahead of the station, flying tail toward Earth with its payload bay facing the lab complex, Endeavour's docking system engaged its counterpart on the station at 9:59 a.m. to cap a two-day orbital chase. About a half hour later, leak checks between the shuttle and the station's PMA-2 docking port were complete and the station's four massive gyroscopes assumed attitude control of the combined spacecraft. But the Endeavour astronauts were not able to enter the station today because the shuttle's cabin air pressure was lowered from 14.7 psi to 10.2 psi Friday to help Hadfield and Parazynski purge nitrogen from their bloodstreams. The astronauts did, however, open the hatches leading into the PMA-2 docking port to position supplies needed by the station crew before Sunday's spacewalk. The Alpha astronauts - commander Yuri Usachev, Susan Helms and James Voss - floated into PMA-2 later to retrieve the items delivered by the shuttle's crew. The major item was electrical cabling needed to bypass an overly sensitive ground fault interrupt circuit that was tripping breakers in the power supply used by the robotic work station needed to operate the new Canadarm 2 crane. Endeavour's crew also left the station astronauts a bit of fresh coffee, fruit and vegetables, welcome additions to their typically freeze-dried menu. Station flight director John Curry said Alpha's complex systems are in good shape, including a Russian carbon dioxide removal device that was acting up Friday. THe Vozdukh system can operate in a variety of modes depending on how many crew members it is supporting. On Friday, it was stuck in Mode 3, meaning it could support the station's three-person crew but no more. That wasn't an issue for Endeavour's docking because the shuttle's CO2-absorbing lithium hydroxide canisters can handle the full load on their own. But flight controllers wanted to fix the problem before arrival of a Soyuz spacecraft April 30 carrying U.S. businessman Dennis Tito and two crewmates. Working in Mode 3, the Vozdukh would not have been able to handle the load of the increased six-member crew, forcing them to tap into the station's own supply of lithium hydroxide canisters. Eighteen such canisters currently are on board the station, enough for 15 days. Endeavour's crew is delivering 10 more. Overnight Friday, however, the Vozdukh suddenly shifted into Mode 5, providing enough CO2 scrubbing for five crew members "There was some troubleshooting planned (today), but Vozdukh overnight started working a little bit more efficiently in what we call Mode 5, which means it can maintain the levels for a three-person crew and we decided not to do any major maintenance on that today," Curry said. If the Vozdukh stays in Mode 5, the crew will still need to use lithium hydroxide during the upcoming visit by Tito and company. But Curry said only one or two of the 28 canisters that will be on board will be needed. =================================================================== Canadarm 2 installed on space station (04/22/01) 05:00 a.m., 04/22/01, Update: Space crane installation work begins Kicking off a busy day in space, Endeavour pilot Jeffrey Ashby, operating the shuttle's robot arm, lifted a Spacelab pallet carrying the new Canadarm 2 space crane out of its berth in the ship's cargo bay at 4:42 a.m. EDT. If all goes well, the pallet will be mounted on the hull of the space station's Destiny laboratory module shortly before 6 a.m., setting the stage for a planned six-and-a-half-hour spacewalk by Canadian astronaut Chris Hadfield and Scott Parazynski. The new robot arm was launched folded up and unpowered and the first item on the agenda today is for Hadfield and Parazynski to attach interim power cables. The arm later will receive power and relay telemetry through a so-called power and data grapple fixture, or PDGF, already in place on Destiny's hull. After connecting the interim power cables, Hadfield and Parazynski will unbolt eight so-called "superbolts" holding the folded space crane to the Spacelab Pallet. "The number one objective during spacewalk number one is to provide power to the arm so it can warm itself up," Hadfield said before launch. "So the first thing we have to do is hook up the wiring and then once it's warmed up for a little while, we will start undoing these enormous superbolts." But first, the spacewalkers will remove a new UHF space-to-space radio antenna from the shuttle's cargo bay and mount it near the forward end of the Destiny module. Then, with the Canadarm 2 properly warmed up, they will turn their attention to unfolding its booms and bolting them together. "With myself riding on the end of the shuttle arm and Scott providing a manual lift and then guidance on the other end, we are going to unfold that arm through 180 degrees and actually bolt it together," Hadfield said. Lead spacewalk planner Jeff Patrick said Parazynski, his feet anchored in a foot restraint, "basically does a clean and jerk on the booms, raises the lower booms up so they're about at his head level." The boom joints will be bolted together with fasteners that work like concrete bolts, expanding internally as they are tightened to rigidly lock the arm members together. Once that work is complete, Hadfield and Parazynski will return to Endeavour's airlock, ending the excursion around 1:36 p.m. A few minutes later, space station astronaut Susan Helms, working at a robotic work station inside Destiny, will send commands to elevate the Canadarm 2 boom into an overnight park position. Today's mission status briefing is scheduled for 2:30 p.m. and NASA's daily highlights reel will begin airing on NASA television at 6 p.m. Crew sleep begins at 6:41 p.m. For readers scoring at home, here is a detailed timeline of today's activity (ISS: international space station; IMAX: large format camera; SSRMS: Canadarm 2 space crane): MET TIME.......DD...HH...MM...EVENT 04/22/01 - Flight Day 4 02:41 AM...02...12...00...Crew wakeup 03:01 AM...02...12...20...ISS: Crew wakeup 04:11 AM...02...13...30...Shuttle robot arm (RMS) powerup 04:26 AM...02...13...45...ISS: Daily planning tagup 04:26 AM...02...13...45...RMS grapples Spacelab pallet (SLP) 04:36 AM...02...13...55...SLP unberthed 04:51 AM...02...14...10...Spacewalk (EVA) preparations begin 04:56 AM...02...14...15...ISS: IMAX operations 05:16 AM...02...14...35...SLP translation begins 05:46 AM...02...15...05...SSRMS/SLP attached to ISS 05:46 AM...02...15...05...ISS: SSRMS procedures review 06:16 AM...02...15...35...Oxygen pre-breathe begins for spacewalkers 06:51 AM...02...16...10...RMS ungrapples SLP 07:06 AM...02...16...25...EVA-1: Airlock depressurization begins 07:21 AM...02...16...40...EVA-1: Airlock egress - spacewalk begins 07:36 AM...02...16...55...EVA-1: Sortie setup 07:36 AM...02...16...55...Cabin repress to 14.7 psi 08:21 AM...02...17...40...EVA-1: FSEGF cable connection 08:21 AM...02...17...40...ISS: IMAX operations 08:41 AM...02...18...00...ISS: Meal 09:06 AM...02...18...25...EVA-1: UHF antenna installation 09:21 AM...02...18...40...ISS: IMAX operations 10:06 AM...02...19...25...SSRMS deployed in overnight park position 01:06 PM...02...22...25...EVA-1: Sortie cleanup 01:36 PM...02...22...55...EVA-1: Airlock ingress 01:51 PM...02...23...10...EVA-1: Airlock repressurization 01:51 PM...02...23...10...Ashby exercises 02:01 PM...02...23...20...ISS: SSRMS boom raised 02:06 PM...02...23...25...Spacesuit servicing 02:41 PM...03...00...00...Rominger exercises 03:16 PM...03...00...35...ISS: VDU routing test 03:51 PM...03...01...10...RMS powerdown 04:16 PM...03...01...35...ISS: Daily tagup 06:31 PM...03...03...50...ISS: Crew sleep begins 06:41 PM...03...04...00...STS crew sleep begins 07:50 a.m., 04/22/01, Update: Critical assembly spacewalk begins Floating in the shuttle Endeavour's cramped airlock, astronauts Scott Parazynski and Canadian Chris Hadfield switched their spacesuits to internal battery power at 7:45 a.m. this morning to officially begin the 103rd spacewalk in U.S. history. The goal of the planned six-and-a-half-hour excursion is to assemble and activate the $900 million Canadarm 2 space crane on the hull of the U.S. laboratory module Destiny. The 57-foot robot arm is needed in June to attach the station's main airlock, which will enable station crews to carry out assembly and maintenance spacewalks between shuttle visits. This is the 63rd U.S. spacewalk and the 19th devoted to space station assembly. For the statistically minded, here are the station numbers: NO..FLIGHT....DATE.......HH...MM...ISS MISSION/SPACEWALKER 3...STS-88....12/07/98...07...21...ISS-2A: Node 1 connection to Zarya (Ross, Newman) 12/09/98...07...02...ISS-2A 12/12/98...06...59...ISS-2A 1...STS-96....05/29/99...07...55...ISS-2A.1: Station outfitting (Jernigan, Barry) 1...STS-101...05/21/00...06...44...ISS-2A.2a: Station outfitting (Voss, Williams) 1...STS-106...09/11/00...06...14...ISS-2A.2b: Zvezda connections (Lu, Malenchenko) 4...STS-92....10/15/00...06...28...ISS-3A: Z1, PMA-3 (Chiao, McArthur) 10/16/00...07...07...ISS-3A (Wisoff, Lopez-Alegria) 10/17/00...06...48...ISS-3A (Chiao, McArthur) 10/18/00...06...56...ISS-3A (Wisoff, Lopez-Alegria) 3...STS-97....12/03/00...07...33...ISS-4A: P6 solar array truss (Tanner, Noriega) 12/05/00...06...37...ISS-4A 12/07/00...05...10...ISS-4A 3...STS-98....02/10/01...07...34...ISS-5A: Destiny lab module (Jones, Curbeam) 02/12/01...06...50...ISS-5A 02/14/01...05...25...ISS-5A 2...STS-102...03/11/01...08...56...ISS-5A.1: Station outfitting (Voss and Helms) 03/13/01...06...21...ISS-5A.1: Same (Thomas and Richards) TOTALS: 18..7 flights...........124...00...19 U.S. astronauts 1 Russian cosmonaut 03:55 p.m., 04/22/01, Update: Astronauts wrap up successful spacewalk Editor's Note... The following story also is posted on the Spaceflight Now web site. Spacewalkers Chris Hadfield and Scott Parazynski, clearly awed by the view from 243 miles up, successfully assembled and deployed the space station's new $900 million Canadian-built robot arm today after briefly wrestling with a set of balky fasteners. Shortly after the spacewalkers returned to Endeavour's airlock, space station astronaut Susan Helms, operating the arm for the first time from a computer work station in the Destiny laboratory module, sent commands to begin unfolding the new space crane. "And Houston, the big arm's in motion," Helms matter-of-factly reported at 2:54 p.m., marking a major milestone in the 104th shuttle mission. The arm was left in an extended "park" position overnight, both of its identical ends locked to a Spacelab launch pallet temporarily bolted to the Destiny module's hull. On Monday, Helms will power up the arm, unlatch one end and plug it into a power and data socket on Destiny's hull. The other end of the arm later will hand the Spacelab launch cradle back to the shuttle's robot arm - also built by Canada - for return to Earth. The arm, able to move end-over-end about the station like an inchworm, is required for installation of the station's main airlock in June. Getting it assembled today was a major milestone in the complex system's checkout and activation. "This is a major component, it's actually in the critical path, required to be fully functional prior to the next shuttle mission when we actually install the airlock," said lead station flight director John Curry. "And today went perfectly, beautifully, from a station arm perspective." Benoit Marcotte, director of operations for the Canadian Space Agency, said "today is really an awesome day for Canada." "We've reached two key milestones in our space development," he said. "The first one being a first-ever EVA for a Canadian astronaut and the second one was just accomplished when we saw Canadarm 2 making its first movements on its own power. "So it is important to note on the 22nd of April for us in Canada that we're joining the international space station, contributing the next major element to the station." Hadfield and Parazynski began the 103 spacewalk in U.S. space history - the 19th devoted to space station construction - at 7:45 a.m. The seven-hour 10-minute excursion officially ended at 2:55 p.m. when the astronauts began repressurizing the shuttle Endeavour's airlock. While some spacewalkers adopt a strictly-business attitude and seldom comment on the spectacular vista below, Parazynski and Hadfield could not help marveling aloud thoughout the spacewalk, attempting to share the view with flight controllers in Houston. "Words cannot describe this experience," Hadfield said shortly after the spacewalk began. "Well, we'll give it a shot," Parazynski quipped. "Just in case people think astronauts aren't poetic." And Hadfield did just that. "There's just a beautiful inevitability of the way this moves along, this station," he marveled as the spacecraft approached the coast of Chile at five miles per second. "Like a graceful, enormous building, just unstoppably plowing along up here. It's just beautiful, with the world rolling underneath." Toward the end of the excursion, Hadfield took a moment to turn off his helmet lights and enjoy the view of the aurora. "Oh wow! Northern Lights!" Hadfield exclaimed. "Really? Wow!" Parazynski replied. "I just shut off my lights while I'm translating across (the station) and way off to orbiter starboard... where are we?" "We're off the southwest corner of Australia," astronaut John Phillips replied from Endeavour's flight deck. "Southern lights. Wow. That's beautiful," Hadfield said. "There's lightning down below me and just the whole horizon is lit up green with tendrils going up into space off to the south. That is beautiful. Oh wow..." The Canadarm 2 was launched on a Spacelab pallet, unpowered and with its two long booms folded in half and doubled over. Parazynski first attached four electrical lines so internal heaters could begin warming up the booms and joints prior to deployment. While the arm warmed up, Parazynski and Hadfield installed a new UHF radio antenna near the station's PMA-2 shuttle docking port to improve communications between arriving shuttles and station crews. They then returned to the Canadarm 2 and removed eight so-called superbolts locking the arm in place on the Spacelab pallet. "This is, Scott," Hadfield said at 10:20 a.m. as Parazynski began removing smaller bolts holding the meter-long superbolts in place. "Yep, I've got it." "Canadarm 2 is staying in space!" With Hadfield providing guidance, Parazynski then lifted the arm's folded booms to an angle of about 35 degrees. "Going for the gold and the world record..." Parazynski joked as he began lifting. It took about 65 pounds of force to move the booms. "We have motion," Hadfield said. "You've come five degrees, you've come eight, 10 degrees... Looking marvelous..." "OK, great." When the folded booms elevated to 35 degrees, Hadfield then climbed on the end of the shuttle's robot arm, grabbed the other end of the booms and unfolded them completely. To lock the extended booms in place, the spacewalkers took turns using a power wrench to turn internal fasteners designed to expand like concrete bolts. And that's when the day's only trouble cropped up. The fasteners did not initially take hold at the torque settings expected. The spacewalkers then cranked up the torque in stages and repeatedly tightened the fasteners until - finally - they would not budge any more. In the middle of that, Hadfield reported a drop of soap used to clean his helmet visor apparently had floated into his right eye, causing quite a bit of irritation. He was told to increase the flow of air through his helmet and within a few minutes, he reported the condition was improving. "My eye's definitely getting better," he said. "My right eye is kind of half closed all the time, but I think it's going to clear." With the arm booms locked in place, Parazynski and Hadfield began cleaning up, taking a moment to looking into the Destiny module's picture window where Helms could be seen smiling and waving back. Station astronaut James Voss then filmed the spacewalkers using a large-format IMAX camera before Hadfield and Parazynski headed back to Endeavour's airlock. As they did so, Canadian astronaut Steven MacLean in mission control radioed up a tribute to Hadfield and the Canadian arm, playing a recording of "Oh Canada" over the air-to-ground radio loop. "And Chris and Scott, we'ree real proud of your work up there getting Canadarm 2 operational," he said when the song ended. "And if you turn around and look down, I believe you're right over Newfoundland." "We are indeed!" Hadfield exclaimed. "Thank you very much to all the people who helped put the arm up here. Scott and I were just the deliverymen. And it really just opens the door to what all of us can be doing together here internationally, beginning to explore space as a planet." "Congratulations," Maclean said. "And I just want to thank you, Steve, for making me an honorary Canadian for today," Parazynski said. "It was real pleasure and an honor and I'm really proud of the work that everyone put into this very complex piece of hardware. It's going to serve the station well for many years to come." =================================================================== SSRMS passes initial tests; Raffaello berthed to ISS (04/23/01) 06:00 a.m., 04/23/01, Update: Shuttle crew enters station; space crane tests on tap The crew of the shuttle Endeavour floated into the international space station at 5:25 a.m. today, greeting the lab's full-time three-member crew with smiles, hugs and handshakes. Floating in the station's roomy Destiny lab module, the two crews chatted and posed for pictures before listening to a quick safety briefing from Expedition Two commander Yuri Usachev. The station crew then took their shuttle counterparts on a tour of the growing 120-ton complex before settling down to a busy day of work. Station astronaut Susan Helms and Canadian spacewalker Chris Hadfield, who helped install the new $900 million Canadarm 2 spacecrane Sunday, will spend the day testing and checking out the 57-foot-long arm's myriad systems, unlatching one end from its launch pallet and plugging it into a power and data socket on Destiny's hull. The other end of the arm will remain attached to the Spacelab launch pallet. On Tuesday, the crane will pick the pallet up and on Wednesday, it will hand it to the shuttle's 50-foot-long robot arm for berthing in Endeavour's cargo bay. While the Canadarm 2 checkout work is going on, astronaut Scott Parazynski will use the shuttle's arm to unberth the Italian Raffaello cargo module and attach it to a downward facing port on the multi-hatch Unity module. Raffaello is packed with 7,500 pounds of equipment and supplies for the station, including two laboratory experiment racks and a two-month supply of food. The cargo module should be in place by noon. Hadfield and Parazynski will take a break at 1:06 p.m. to participate in round-robin interviews with CBS News, CNN and Fox News. Hatches between Endeavour and the station will be closed at 3:11 p.m. in preparation for the mission's second spacewalk Tuesday. The Canadarm 2 currently is drawing power from four temporary cables hooked up Sunday by Hadfield and Parazynski. During Tuesday's spacewalk, the astronauts will route power to the arm socket on Destiny's hull to complete the crane's installation. Revision C of the NASA television schedule is available below, along with an updated flight plan. 02:00 p.m., 04/23/01, Update: Robot arm tests go well; Raffaello docked with station Station astronaut Susan Helms unlimbered and exercised the new Canadarm 2 space crane today, sailing through a series of tests to prove the $900 million robot arm will work as advertised. "We've been very happy to operate the arm today and see that it works extremely well," station astronaut James Voss reported. "It's been a great day for the space station, getting the arm up here. "This will allow us to continue building the space station," he continued. "This is one of those linchpins that had to work and it looks like it's going to work. There's more to do, more testing and we still haven't got it completely in an operational state yet. "But I'm sure everytyhing's going to continue to work well and we're looking forward to using it to keep building the station. Thanks to everybody who supported both in Houston and in Canada to make this all work." With the initial round of arm testing complete, the shuttle Endeavour's crew used the orbiter's shorter robot arm - also built in Canada - to unberth an Italian-built cargo module and attach it to a port on the space station. The linkup was completed shortly after noon. The 4.1-ton Raffaello module is loaded with several tons of equipment and supplies, including two laboratory experiment racks and a two-month food supply. Over the next four days, the station crew, with help from Endeavour's astronauts, will unload the module and repack it with no-longer-needed euipment and trash. The new Canadarm 2 space crane was attached to the station, unfolded and bolted together during a spacewalk Sunday by Scott Parazynski and Chris Hadfield. The high tech crane features two long booms connected by a rotating elbow joint. Each boom is equipped with a snare-like grapple that can lock onto station components or power and data grapple fixtures located at various points around the outpost. The arm was launched with both ends locked to mounting fixtures on a Spacelab cargo pallet. Early today, Helms unlatched one end, extended the arm and locked that boom's latching end effector, or LEE, to a power socket on the far side of the lab's hull. A second spacewalk is on tap Tuesday to route power to that socket. So far, flight controllers are pleased with the arm's initial performance, radioing congratulations to Helms and company when today's round of testing was finished. "Yeah, we see ourselves complete," Helms agreed. "You've got a lot of excited people up here." "And down here, too," replied astronaut Lisa Nowak in space station mission control. "You guys did a great job." =================================================================== Robot arm wired up after problem resolved (04/24/01) 05:45 a.m., 04/24/01, Update: Astronauts awakened for spacewalk The Endeavour astronauts were awakened at 3:41 a.m. to begin preparations for a second spacewalk by Canadian astronaut Chris Hadfield and Scott Parazynski. The primary goal of the excursion, scheduled to begin at 9:06 a.m., is to activate the socket on the Destiny laboratory module's hull where one end of the new Canadarm 2 space crane is plugged in. The 57-foot-long robot arm was carried into orbit folded up and bolted to a Spacelab cargo pallet. The pallet was mounted on the Destiny module's hull Sunday and during the crew's first spacewalk, Hadfield and Parazynski connected temporary power cables and bolted the arm's two main booms together. On Monday, arm operator Susan Helms, working inside the Destiny module, powered up the new crane, unlatched one end and anchored it to a power and data grapple fixture - PDGF - on the far side of Destiny's hull. The PDGF is a sort of high tech power socket delivering electricity to the arm and routing video and telemetry back to a computer workstation inside the lab. The station eventually will be outfitted with a series of PDGFs mounted at strategic points around the outpost, allowing the multi-dextrous Canadarm 2 to walk end over end from one work site to another. But the lone PDGF currently on the station is not yet fully activated. During today's spacewalk, Parazynski, riding on the end of the shuttle's robot arm, will open a utility panel on the lab's hull and make the necessary connections. "We'll be doing a lot of the re-wiring to basically enable the space station arm to live on the space station permanently," Parazynski said. "We'll go out and with Chris's help, take off a shield on the side of the laboratory module and I'll spend the next hour and a half or so doing some fairly delicate work, surgery almost, rewiring some very delicate fiber optic cables to enable the space station arm to live permanently on the station." The spacewalkers also will remove a no-longer-needed UHF antenna from the Unity module's starboard port where the station's main airlock will be installed during a mission in June. Then they will disconnect the Spacelab Pallet electrical umbilicals that initially powered the Canadarm 2. Once the station's arm is powered through the PDGF, Helms will use it to lift the 3,000-pound Spacelab Pallet off the lab cradle assembly to make room for Parazynski to mount a 400-pound spare DC power converter on the station's hull. The arm, with the Spacelab Pallet attached to one end, will be left in an extended position overnight. The shuttle crew, meanwhile, will repressurize Endeavour's cabin to 14.7 pounds per square inch and re-open hatches to the station. NASA planners initially held open the possibility of having Parazynski and Hadfield attempt a bit of repair work on a jammed locking pin in the rotating joint where one of the station's two main solar array panels attaches to a central truss. The pin was causing friction, forcing the array's drive motor to work harder than its counterpart when moving the huge array to track the sun. Overnight, however, flight controllers successfully commanded the balky pin to retract and the so-called beta gimbal joint assembly was given a clean bill of health. "We have some very good news. The BGA latch number two problem, which has been around for a while, has been solved, we think," astronaut Ellen Ochoa radioed from Houston. "It's been successfully unlatched and both arrays are now in autotrack ... and we think the problem is solved." "Well that's good news," station astronaut James Voss replied. "Thanks." Here is a detailed timeline of today's activity (in EDT and mission elapsed time): 05:56 AM...04...15...15...Spacewalk preparations begin 07:11 AM...04...16...30...Station crew begins unloaded cargo module 08:11 AM...04...17...30...Shuttle robot arm powerup 08:51 AM...04...18...10...Airlock depressurization begins 09:06 AM...04...18...25...Airlock egress 09:06 AM...04...18...25...Shuttle cabin repressurized to 14.7 psi 09:16 AM...04...18...35...Spacewalk tool, work platform setup 10:01 AM...04...19...20...Spacewalkers route power to Canadarm 2 10:16 AM...04...19...35...Hadfield removes starboard UHF antenna 11:31 AM...04...20...50...Parazynski releases Spacelab pallet umbilicals 12:16 PM...04...21...35...Canadarm 2 lifts Spacelab pallet 12:36 PM...04...21...55...Canadarm 2 moved to overnight park position 01:01 PM...04...22...20...Spacewalkers install power converter 02:11 PM...04...23...30...Spacewalk sortie cleanup 03:16 PM...05...00...35...Shuttle robot arm powerdown 03:16 PM...05...00...35...Airlock ingress 03:31 PM...05...00...50...Airlock repressurization (spacewalk ends) 04:56 PM...05...02...15...Shuttle/station hatches reopened 05:56 PM...05...03...15...Joint crew meal 07:41 PM...05...05...00...Crew sleep begins 08:40 a.m., 04/24/01, Update: Spacewalks Astronauts Chris Hadfield and Scott Parazynski switched their spacesuits to internal battery power at 08:34 a.m., officially beginning a planned six-and-a-half-hour spacewalk to route power to the space station's new $900 million robot arm. This is the 104th spacewalk in U.S. history, the 64th in the history of the shuttle program and the 20th devoted to space station assembly. Not counting today's excursion, 20 U.S. astronauts, one Canadian - Hadfield - and one Russian cosmonaut have spent 131 hours and 10 minutes during nine shuttle flights putting the space station together. 05:30 p.m., 04/24/01, Update: Spacewalkers overcome robot arm power glitch; accomplish all major objectives Two spacewalking electricians wired the international space station's new robot arm into the lab's power grid today, completing the $900 million crane system's initial installation after extensive troubleshooting to activate an initially dead backup circuit. "And Endeavour, Houston, great job," astronaut Ellen Ochoa radioed from mission control when juice finally started flowing through the backup power cable. "We're all celebrating down here." "That's great. That's just outstanding news," replied spacewalker Scott Parazynski. Station astronaut Susan Helms, the robot arm's primary operator, then powered up the crane for its first attempt at heavy lifting. To the delight of flight controllers following along in Houston, the arm smoothly lifted a 3,000-pound cargo pallet away from the station's main lab module. "I'm absolutely ecstatic," lead flight director Phil Engelauf told reporters later. "I think this was just a red letter day in the program, just an absolutely wonderful experience. We got to where we wanted to be at the end of the day. ... We just got everything done we could have hoped for today and a little bit more. The mission is headed for great success." Added space station flight director John Curry: "We got our money's worth today. Both flight control teams and the crews - the spacewalk crew, the Expedition Two crew as well as the shuttle crew on orbit - just did an outstanding job. "It's just incredible to me we're sitting here having accomplished nearly all of the goals we set out to do today given the challenges we had." The 57-foot-long Canadarm 2 space crane was launched unpowered and folded up on a Spacelab cargo pallet in the shuttle Endeavour's payload bay. The pallet was mounted on the hull of the station's Destiny lab module Sunday and the robot arm's two main booms were unfolded and bolted together by Parazynski and Canadian Chris Hadfield during the mission's first spacewalk. Helms powered up the new crane Monday, unlatched one end and locked it on a power and data grapple fixture on the far side of Destiny's hull. The high-tech PDGF is designed to provide power to the crane and to relay telemetry and video from four television cameras back to operators inside the station. The robot arm can lock onto such grapple fixtures with either end, allowing it to move around the station end over end to reach various work sites. The primary goal of today's spacewalk, the 104th in U.S. history and the 20th devoted to space station assembly, was to connect two power lines just under the lab module's outer skin to route power to the PDGF. Other objectives included removal of a no-longer-needed UHF radio antenna and attachment of a spare 400-pound direct current switching unit on the station's hull. Parazynski had no trouble hooking up the primary and secondary power lines for the Canadarm 2 space crane. Helms, inside the Destiny module, then attempted to route so-called "keep alive" power through the backup cable. But the line was dead. She then routed power to the primary cable. To everyone's relief, electricity finally began flowing. "Good keep alive on the prime string," Helms reported. "We copy, very good news," Lisa Nowak replied from the ISS control center. "We feel a little relieved, too," Helms agreed. Confident the arm had at least one good source of power, flight controllers told Parazynski to unplug both the primary and secondary cables, inspect the connectors and then plug them back in. He did just that, but there were no obvious signs of trouble. Helms reconnected both circuits and again, the primary system worked, the backup did not. Increasingly concerned engineers then asked Parazynski and fellow spacewalker Chris Hadfield to begin unplugging and reconnecting other cables in the secondary circuit, starting with the horseshoe-shaped connecter used to hook the secondary cable directly into the arm's grapple fixture. The fixture was installed during a shuttle flight earlier this year and the cable in question was bolted into place during that flight. Using a power wrench to back off the connector's central hold-down bolt, Parazynski unplugged the cable, did not see any problems with the connecter, and plugged it back in. This time, when Helms switched the power back on electricity flowed into the arm. "And Endeavour, Houston, great job. We're all celebrating down here," astronaut Ellen Ochoa radioed from mission control. "That's great. That's just outstanding news," Parazynski replied. Curry said engineers suspect the connector was never fully engaged when it was installed earlier this year. While all of that was going on, Hadfield was removing the UHF antenna from the Unity module's starboard hatch. While disconnecting the antenna feed lines, a washer-like fastener somehow floated free and disappeared behind thermal covers over the port's berthing mechanism. Hadfield made numerous attempts to recover the lost part, but he was unsuccessful. The Canadarm 2 robot arm is made up of two long booms connected by a rotating elbow joint. Both ends of the crane are equipped with snare-like grapple fixtures and either one can be used to anchor the crane on a power and data grapple fixture. The other end can then be used to grab station modules, hardware or astronaut work platforms. The arm draws power from the PDGF and uses it to send video and data back to the arm's operator inside the station. Only one such PDGF is currently installed. But the station eventually will be equipped with a dozen or so PDGFs. The arm will be able to move from one to another, end over end, to reach various work sites. Before the arm and its operators can run, however, they must first learn to walk. And today, the arm "switched ends" for the first time when Helms lifted the no-longer-needed Spacelab pallet away from the Destiny module. With the arm and pallet well out of the way, Parazynski and Hadfield attached the spare DC power switching unit to the station's hull before heading back to Endeavour's airlock. The spacewalk officially began at 8:34 a.m. and ended at 4:14 p.m. for a duration of seven hours and 40 minutes. Through 21 space station assembly EVAs, 19 NASA astronauts, one Canadian - Hadfield - and one Russian cosmonaut have logged 138 hours and 50 minutes of spacewalk time. If all goes well, Helms will use the station's new arm to hand the Spacelab pallet back to the shuttle's shorter robot arm Wednesday so it can be restowed in Endeavour's cargo bay for return to Earth. The huge crane will begin assisting in actual space station assembly in June, when Helms will use it to attach the station's main airlock. 06:10 p.m., 04/24/01, Update: Clarifying cost of Canadian robot arm During a news briefing by Canadian Space Agency officials before the shuttle Endeavour's launch, reporters were told the space station's new Canadian-built robot arm cost $1.4 billion in Canadian dollars. That works out to $900 million U.S. for design, development and fabrication. As it turns out, that cost covers the entire crane system, that is, the arm launched aboard Endeavour; a mobile platform that will be launched later to carry the arm along the station's central truss; and a fine-precision robot hand attachment called a dextrous manipulator. A CSA representative said today the Canadian project will total nearly $900 million U.S. over the entire 20-year course of the project. The arm alone is valued at roughly $600 million. =================================================================== Space station computers drop off line (04/25/01) 06:30 a.m., 04/25/01, Update: Astronauts gear up for complex robot arm operations The international space station's new robot arm will be put to the test today, maneuvering a 3,000-pound cargo pallet about to make sure it can do the heavy lifting required for subsequent station assembly flights. The arm was launched unpowered and folded up on a Spacelab Pallet mounted in the shuttle Endeavour's cargo bay. The arm has now been assembled, powered up and attached to the hull of the Destiny laboratory module. The 57-foot-long crane is made up of two long booms connected at a rotating elbow joint. Each boom is equipped with complex wrist joints and a grappling snare on each end. Either end can be used to anchor the crane or latch on to station components. After assembly and initial checkout, one end was locked onto the hull of the station's Destiny laboratory module. The other end remains latched onto the Spacelab Pallet that carried it into orbit. Today, astronaut Susan Helms, operating the Canadarm 2 space crane from a work station inside Destiny, will move the cradle through a series of maneuvers to test the arm's performance with a load on one end. She then will "hand it off" to the shuttle's robot arm, which will berth the pallet back in Endeavour's cargo bay for return to Earth. The tests today, and additional checkout work Thursday, will clear the way for the next station assembly flight in June - flight 7A - when the Canadarm 2 will be used to install the station's main airlock. "The arm ... has been tested for years and years in simulation and on the ground," Canadian astronaut Chris Hadfield said in a NASA interview. "But you don't really know until you go do it for real. And we have to use this arm on the flight after ours to assemble the space station. It has to be a trusted, proven piece of hardware by 7A, by the flight after ours. "So just like any new piece of hardware, you want to move it each direction and shake it a little bit and see that it behaves the way you think. This cradle weighs 3,000 pounds. And so here is a nice, big, heavy mass on the end of the arm and you can do all these tests: Shaking it and moving quickly and stopping and making sure that all the math was right." Hadfield and astronaut Scott Parazynski installed the crane during two spacewalks Sunday and Tuesday. For today's arm operations, Hadfield will assist Helms during the Canadarm 2 pallet maneuvers, then move back to Endeavour to operate the shuttle's Canadian-built arm for the pallet handoff. "The Spacelab Pallet weighs on the order of 3,000 pounds, so they'll check out the dynamics features of the arm with a load at the end of it, check out the video systems on board, check out the performance of all of the various capabilities that the arm has to offer," Parazynski said. "It's a three- or four-hour activity to shake down the arm and then deliver it to a point where the shuttle arm can now pick up the Spacelab Pallet. Chris, who hails from Canada of course, will be doing the honors there. Kind of very nice symbolic thing as well, to be able to, for the very first time, have both Canadarms operational. "He'll be grabbing the Spacelab Pallet offered up by the space station arm and retrieve that from the station crew. The station will then back away the SSRMS and Chris will then berth the Spacelab Pallet back into the payload bay." Here is a timeline for today's activity (in EDT and mission elapsed time): MET EDT........DD...HH...MM...EVENT 06:06 AM...05...15...25...Shuttle robot arm (RMS) powerup 06:21 AM...05...15...40...Spacelab Pallet (SLP) maneuvers 06:46 AM...05...16...05...SLP maneuvered to handoff position 08:11 AM...05...17...30...Shuttle RMS locks onto SLP 08:46 AM...05...18...05...SLP handoff: Shuttle arm takes SLP 10:11 AM...05...19...30...Crew meals begin (staggered schedule) 10:16 AM...05...19...35...SLP berthed in payload bay 11:11 AM...05...20...30...Italian VIP call to Umberto Guidoni 11:21 AM...05...20...40...SLP ungrappled 11:36 AM...05...20...55...RMS powerdown 12:30 PM...05...21...49...Mission status briefing on NASA TV 01:51 PM...05...23...10...Russian media event with Yuri Lonchakov 03:26 PM...06...00...45...Reboost operations begin 07:00 PM...06...04...19...Daily highlights reel begins airing 07:41 PM...06...05...00...STS crew sleep begins 08:30 a.m., 04/25/01, Update: Robot arm tests delayed by station computer glitch Problems with two command and control computers aboard the international space station have delayed the start of today's robot arm operations. Command and control computer No. 1 shut down last night during crew sleep and C&C 2 is having problems accessing data on the station's file server that is needed for tests of the Canadarm 2 space crane. Engineers thought they had the problem fixed earlier this morning, but C&C 2 once again ran into problems linking to the file server. A third command and control computer is available and it is in good health. But it would take about 90 minutes to switch over to that machine. Flight controllers are assessing the situation to determine the best course of action. In the meantime, robot arm operations are on hold and the station crew is pressing ahead with work to unload the Raffaello cargo module. 08:50 a.m., 04/25/01, Update: Station crew adjusts schedule while Houston switches to backup computer Flight controllers have decided to activated a backup command and control computer aboard the international space station to take over from two other machines that have experienced problems today. The changeover to control computer No. 3 is expected to take about two hours. An operational computer capable of accessing data from the station's mass memory unit is required before the crew can begin today's planned tests of the station's new Canadian-built robot arm. As a result, the astronauts are shifting gears and pressing ahead with cargo transfer work originally scheduled for later this afternoon while flight controllers configure the station's computer system. If all goes well, the robotic operations with the Canadarm 2 will begin shortly after 11 a.m. 11:05 a.m., 04/25/01, Update: Russian CO2 air scrubber shuts down Already wrestling with computer problems, the space station crew now faces trouble with the Russian Vozdukh carbon dioxide removal system in the Zvezda command module. The system shut down a few minutes before 11 a.m. The astronauts are not in any danger because the shuttle Endeavour's lithium hydroxide system can handle most of the load and the station has its own supply of LIOH canisters. But the Vozdukh needs to be returned to service as soon as possible to avoid cutting too far into those limited on-board supplies. The Vozdukh has had problems in recent weeks, working in a degraded capacity. Just before Endeavour's launch, it was operating in Mode 3, meaning it could only support three people. A few days later, the scrubber's performance suddenly improved to Mode 5 on its own. Russian engineers believe the crew may be able to correct the problem by replacing a suspect component. But a repair plan has not yet been finalized. 11:40 a.m., 04/25/01, Update: Backup computer activated; still 'no joy' A backup command and control computer was activated today after problems earlier in the day when one computer shut down and a second ran into problems connecting to the station's main data storage unit. But the third backup computer also was unable to connect to the data server. If the trouble cannot be corrected soon, already delayed tests of the station's new Canadian robot arm will be deferred until Thursday. 04:30 p.m., 04/25/01, Update: Computer glitch baffles engineers, disrupts station schedule A subtle and so-far-baffling problem with the international space station's central computer system disrupted operations in orbit today, forcing the crew to delay critical tests of the lab's new robot arm amid extensive troubleshooting on the ground to come up with a fix. The computer glitch disabled the station's main Ku-band antenna and prevented the crew from accessing shared software loaded on a central storage device. Other systems, however, were not affected and the station's critical power and life support systems continued operating normally. "It appears the systems on board the spacecraft are still functioning properly, the solar arrays are tracking (the sun) as they should be, we're in attitude, clearly the crew on board the station is doing fine," said Milt Heflin of NASA"s mission operations directorate. "So the situation is strange to us at this point and we're trying to sort that out," he added. "Yet it doesn't appear to be causing huge problems on board the station." On a positive note, the Russian Vozdukh carbon dioxide removal system in the Zvezda command module is back in operation after unexpectedly shutting down earlier today. The Vozdukh has been acting erratically in recent days and Russian engineers have been debating a plan to have the crew replace its central control computer. Station commander Yuri Usachev coaxed the air scrubber back into action this afternoon by turning it off and back on again. Engineers may still opt to replace the controller but for now, the Vozdukh is working. The computer problem is more complex. The problem first surface about 40 minutes after the crew went to bed last night when command and control computer No. 1 suddenly shut down. Flight controllers at the Johnson Space Center in Houston then brought C&C-2 on line and it appeared to be working normally. But this morning, when the crew attempted to load robot arm test software, C&C-2 was unable to link up with the station's shared data storage system. Flight controllers eventually decided to activate yet a third C&C computer and after a two-hour switch over, discovered that it, too, could not communicate with the storage device. "It's almost like being in a simulation," Heflin said. "We're into something here we don't understand. ... They think it's probably software related. But that's going to be part of the troubleshooting process." While three C&Cs are on board the station, only one operates at any given time. With all three unable to load robot arm test software, the station crew was forced to replan its day, deferring additional arm tests to Thursday and pressing ahead instead with work to unload the Raffaello cargo module. The computer glitch also put a planned shuttle reboost maneuver on hold. "It took the activities we had planned to do and jumbled that around somewhat," Heflin said. Asked if NASA's mission management team might consider a mission extension if the computer glitch isn't straightened out by Thursday, Heflin said "that clearly has the potential of being in the mix of the discussion, there's no doubt about it." "We do have the capability for an extension day," he said. "So I think we're going to have to allow the rest of the day to complete (troubleshooting) to see where we get to and see where we are in the morning." 05:40 p.m., 04/25/01, Update: Flight director briefs crew on computer problem Engineers at the Johnson Space Center do not yet know what might have disabled the international space station's command and control computer system, a potentially crippling glitch that has triggered a massive troubleshooting effort in Houston. Station flight director Mark Ferring told the crew late today engineers are working around the clock to resolve the problem, if possible, by crew wakeup Thursday morning. Overnight, engineers will attempt to uplink commands into the station's command and control - C&C - computer system to activate another backup computer and to diagnose what went wrong in the first place. But the lab's Ku-band antenna system is not able to track NASA's communications satellites, making it difficult to uplink the proper commands. "What we're going to be doing is looking and seeing if we can re-establish command capability," Ferring said. "We have a good forward link with the UHF but we hven't used that before so we've kind of resisted attempting to command through that. But we may start looking at that over the next hour or so. "The only other thing is we're only running, we believe, off C&C MDM No. 3 and there seems to be some problem with it putting telemetry on the downlink. So we're looking at ways of potentially power cycling back to one of the other C&C MDMs and including them so they can load a new set of brains into the computer. "But right now, we of course have to establish a command link to do those kind of things. So that's going to be our first order of business." "It doesn't sound like you're going to get much sleep tonight," station astronaut Susan Helms replied. "No, and I think you can rest assured that anyone who knows anything about a computer is now at JSC here and we're all working hard on it," Ferring replied." "Well, we're hopeful that you'll have a good, successful evening," Helms said. "Thanks, Mark." "Thank you very much. And we hope we can get this done so you'll have a successful and fun day with the (robot) arm tomorrow." Helms then asked Ferring if the engineers had any idea what caused the problem. "We do not yet understand what the problem is," Ferring said. "We're still scratching our heads." 08:30 p.m., 04/25/01, Update: NASA managers say crew in no danger; optimistic about computer fix Editor's Note... The following story also is posted on the Spaceflight Now web site. The international space station's three main control computers were crippled today by a subtle and so-far-baffling software glitch that disrupted normal operations, forced the crew to delay critical robot arm tests and triggered a massive troubleshooting effort in Houston. The station's life support systems continue to operate normally, its huge U.S. solar arrays are tracking the sun and generating power as required and the lab's crew is not in any immediate danger. But flight controllers are not receiving telemetry from the command and control computers and have no insight into what might have knocked them out of action. Station flight director Mark Ferring told the crew late today engineers are working around the clock to resolve the problem, if possible, by crew wakeup Thursday morning. "It doesn't sound like you're going to get much sleep tonight," station astronaut Susan Helms replied. "No, and I think you can rest assured that anyone who knows anything about a computer is now at JSC here and we're all working hard on it," Ferring said. Overnight, engineers will attempt to uplink commands into the station's command and control - C&C - computer system to diagnose what went wrong in the first place. But in the system's current condition, the station's Ku-band antenna system is not able to track NASA's communications satellites, making it difficult to uplink the necessary commands. "What we're going to be doing is looking and seeing if we can re-establish command capability," Ferring told Helms. "We have a good forward link with the UHF but we haven't used that before so we've kind of resisted attempting to command through that." An initial attempt using the UHF system to command a light in the Destiny laboratory module to turn off was unsuccessful. On a positive note, the Russian Vozdukh carbon dioxide removal system in the Zvezda command module is back in operation after unexpectedly shutting down earlier today. The Vozdukh has been acting erratically in recent days and Russian engineers have been debating a plan to have the crew replace its central control computer. Station commander Yuri Usachev coaxed the air scrubber back into action this afternoon by turning it off and back on again. Engineers may still opt to replace the controller but for now, the Vozdukh is working. The computer problem is more complex. And potentially serious. During normal operations, one of the three C&C computers, known as a multiplexer/demultiplexer, operates as the "prime" machine, allowing station astronauts and ground controllers to send commands to various systems and providing critical telemetry. A second C&C computer operates in backup mode, ready to take over if the prime computer suffers a problem, and the third machine operates in standby in a domino-like software architecture. Just before 9 p.m. Tuesday, about 40 minutes after the station crew went to bed, command and control computer No. 1 suddenly shut down. As expected, C&C-2 then assumed the role as prime computer while C&C-3 switched from standy into backup mode. C&C-2 initially appeared to be working normally. But this morning, the computer began having problems loading data from an internal hard drive. After troubleshooting the problem, flight controllers decided to switch C&C-2 into backup mode, which caused C&C-3 to take over as the prime computer in the chain. To the surprise of engineers on the ground, C&C-3 ran into problems accessing its hard drive and shortly thereafter the machine stopped providing telemetry. "It's almost like being in a simulation," said mission operations representative Milt Heflin. "We're into something here we don't understand. ... They think it's probably software related. But that's going to be part of the troubleshooting process." Station flight director Andrew Algate told reporters later the problem almost certainly is due to a software conflict of some sort because all three computers were affected by a similar problem. He said he was confident engineers will figure out a solution and refused to speculate on what might happen if they are not successful. Endeavour's crew is scheduled to undock Saturday. That same day, the Russians plan to launch a fresh Soyuz spacecraft to the station. The three-man crew, including millionaire space tourist Dennis Tito, is scheduled to dock with the outpost Monday. Algate would not address what possible impact the computer problem might have on the Soyuz launch, saying only that it posed no immediate threat to the station's current crew. Systems in the Russian modules of the space station continue to operate normally and in a worst-case scenario, he said, all three crew members could simply retreat to the Russian segment while engineers continue troubleshooting. But he said he does not believe it will come to that. Mike Rodriggs, a software engineer at the Johnson Space Center, said engineers hope to uplink commands later in the evening that will cause the computer that originally failed, C&C-1, to switch back into primary mode. Switching in this fashion may recover use of the machine. If all else fails, engineers may elect to reboot one of the machines. But that is a last resort because rebooting would erase any data that might explain what caused the original problem. In the meantime, NASA managers are holding open the option of extending Endeavour's mission a day, depending on how the computer troubleshooting goes, to give the crew time to complete tests and checkout of the station's newly installed robot arm. If the computer glitch is corrected overnight, the arm will be put through its paces Thursday, handing a 3,000-pound cargo pallet back to the shuttle robot arm for reberthing in Endeavour's cargo bay. The Canadarm 2 crane also will be put through a dry run of the maneuvers it will need to make in June during installation of the station's main airlock. If the computer problem persists, the airlock installation dry run will be deferred and a minimal set of tests will be carried out Friday. "We do have the capability for an extension day," said Heflin. "So I think we're going to have to allow the rest of the day to complete (troubleshooting) to see where we get to and see where we are in the morning." In a late afternoon chat with Helms, Ferring said engineers believe C&C No. 3 is active but "there seems to be some problem with it putting telemetry on the downlink. "So we're looking at ways of potentially power cycling back to one of the other C&C MDMs and including them so they can load a new set of brains into the computer," he said shortly before 6 p.m. "But right now, we of course have to establish a command link to do those kind of things. So that's going to be our first order of business." "Well, we're hopeful that you'll have a good, successful evening," Helms said. "Thanks, Mark." "Thank you very much. And we hope we can get this done so you'll have a successful and fun day with the (robot) arm tomorrow." Helms then asked Ferring if the engineers had any idea what caused the problem. "We do not yet understand what the problem is," Ferring said. "We're still scratching our heads." 11:25 p.m., 04/25/01, Update: Engineers coax station computer back on line Software engineers successfully coaxed one of the international space station's three disabled command and control computers back on line this evening more than 24 hours after problems first developed that crippled the outpost and disrupted the crew's schedule. Engineers are able to uplink commands to the computer and downlink station telemetry, but data from the C&C-2 computer remains suspect, indicating possible problems with its internal hard drive. But flight controllers were buoyed by the partial recovery of the computer system and the station's crew, awakened as expected by an alarm when C&C-2 came back on line, encouraged engineers to continue their troubleshooting efforts. =================================================================== Shuttle flight extended one day; computer woes worsen (04/26/01) 05:30 a.m., 04/26/01, Update: Astronauts help engineers with computer troubleshooting Editor's Note... The following story also is posted on the Spaceflight Now web site. After a long night of unsuccessful work on the ground to recover use of the space station's crippled command and control computers, astronaut Susan Helms checked their status using an on-board laptop computer shortly after crew wakeup today and reported one of the machines was, in fact, up and running. The "extraordinarily good news" surprised station flight director Robert Castle and a team of troubleshooters at the Johnson Space Center, giving flight controllers welcome insight into the system and improving prospects for developing a fix. "I think we can help you here," Helms said. "You are making my day," Castle replied. "It's been a long night." All three of the station's command and control - C&C - computers experienced problems accessing their internal hard drives Tuesday and Wednesday, dropping off line one at a time in domino fashion to the bafflement - and increasing alarm - of ground controllers. While the station's critical life support systems, its stabilizing gyroscopes and its two huge solar arrays continued operating normally, engineers on the ground lost all telemetry from the C&C system and were unable to send commands to the system. The computer glitch forced the station astronauts to delay critical tests of the lab's new Canadian robot arm while engineers launched a massive troubleshooting effort to figure out what had gone wrong and what might be needed to regain use of the C&C computers. Shortly before 11 p.m. Wednesday, the ground successfully uplinked a command that effectively pulled the plug on the machine that had been in control - C&C-3 - forcing C&C 2 to take over as the station's primary computer. The computer switch over set off an alarm, as expected, that woke up the station crew and for a few minutes it appeared the team was on the road to recovery. But about 40 minutes later, C&C 2 suddenly stopped sending telemetry, leaving ground controllers in the dark once again. Subsequent efforts to gain insight into the system failed and shortly after the crew woke up today, Castle presented a detailed status report. "I wish I had better things to talk about, we're still having significant problems with the C&C MDMs," he said. "I know we woke you guys up last night when we finally got C&C MDM 2 up and running. About 40 minutes after that, we lost telemetry from it again and any of our command tests so far have failed. "So we really don't have any insight into what's going on with any of the C&C MDMs right now. We do have some steps coming up to you in the execute package to try and figure out what is going on." The station is equipped with three command and control multiplexer-demultiplexer computers t- C&C MDMs - that control the lab's operation. Only one computer is in charge at any given time. A second machine runs in backup mode, ready to take over if the primary computer shuts down or malfunctions, and the third machine is in standby, programmed to shift into backup if the designated backup computer switches to primary mode. All three computers apparently ran into a similar software-related problem accessing data from their internal hard drives. And that took all three down, one at a time. This morning, Castle gave the astronauts a brief synopsis of the events that led to the electronic impasse. "We lost C&C 1 yesterday (Tuesday night), of course, due to apparently a mass storage device problem," he said. "C&C 2 ran for a little over eight hours and then e lost to due to again, a mass storage type problem of some sort. It transitioned to 3 and then while operating on 3 we lost telemetry. "We finally recovered C&C 2 by sending a command to just pull power to C&C 3. It went down and C&C number 2 came up. We then lost C&C 2 telemetry and we have been unable to recover. "As far as the overall vehicle status, the momentum management (gyroscope system) continues to run and attitude is holding nicely," Castle continued. "When we had 40 some minutes of telemetry, all the lab systems and the U.S. segment systems appeared to be in very good shape." But without the C&C system in operation, he went on, "we can't do robotic (arm) ops on the station." Instead, Castle told the crew they would spend the morning continuing work to transfer equipment to and from the Raffaello cargo module while ground controllers continued efforts to recover the C&C system. If those efforts worked, he said, the astronauts would be able to use the new Canadarm 2 space crane to hand a Spacelab cargo pallet back to the shuttle's robot arm for reberthing in Endeavour' cargo bay. Other tests would be deferred to Friday. "What's the status of the other two MDMs?" asked station astronaut James Voss. "We're on C&C 2 right now. I know you don't have any data, but what's the status of the other two MDMs? Are they up and running, like in standby or backup?" "Both of them are powered," Castle said. "We don't know where they are. We're guessing they're in diagnostic (mode) but they're not up in standby." And then Helms, using a laptop computer in he Destiny lab module, gave the team a welcome and unexpected surprise. "Bob, we are connected to the MDM and it looks like the data is good," she reported. "It says C&C 1 is in standby and C&C 3 in backup." "OK, well the fact that you're connected is extraordinarily good news!" Castle said. "Since we didn't have IO (input-output) with C&C 1 and 3, I don't know if we can believe their status,. But we can believe that C&C 2 is up and running, which is extraordinarily good news." "Yeah, I just launched the C&C summary and it launched, the purple Ds disappeared and we received data," Helms said. "Purple Ds disappearing is even better news," Castle replied. "OK, if you're ready we can read you a few steps and if they're successful we can get going with this." "I just tried to launch the C&C overviews display and it also, the purple Ds disappeared and we have data. So I think we can help you here," Helms said. "You are making my day. It's been a long night." The computer troubleshooting has wrecked the crew's schedule, forcing the astronauts to put robot arm testing on hold. The new arm cannot be operated without the C&C computers running because those computers are used to provide needed software to the crane's computer control system. The arm currently is extended, holding a 3,000-pound Spacelab cargo pallet on one end. The pallet, which held the arm during Endeavour's launch, must be reberthed in the shuttle's cargo bay for return to Earth. That work had been scheduled for Wednesday and currently is on hold. If the C&C system is recovered this morning, Helms will use the arm to hand the pallet over to the shuttle's robot arm for reberthing. Other tests, including a dry run to rehearse the techniques needed to install the station's main airlock would be deferred to Friday. One other major task that requires an operational C&C system is undocking of the Raffaello cargo module currently attached to the Unity module's downward facing port. Castle told the crew today that in a worst case scenario, they could use a computer in the node itself to operate the latches holding Raffaello in place. Mission managers are holding open the option of extending Endeavour's mission by one day to complete delayed testing and other work depending on what happens with the C&C recovery effort. 02:00 p.m., 04/26/01, Update: 'Mighty Mouse' saves the day Flight controllers regained at least partial control of one of the international space station's critical command computers today after a computer in a different part of the station launched an emergency program called "Mighty Mouse" in a last-ditch bid to save the day. The aptly-named program did its job, automatically turning power to the command computers off and back on again, one at a time, to force one of the machines to reboot from scratch without loading any possibly corrupted software. That apparently did the trick and command-and-control computer No. 2 - C&C-2 - booted up normally. Flight controllers did not realize what had happened, however, until the station's crew woke up early today and used a laptop computer to check the health of the C&C system. To the surprise - and relief - of exhausted flight controllers, Susan Helms reported C&C-2 appeared to be operating normally. The ground team then downloaded the machine's memory to look for clues as to what had gone wrong in the first place and began implementing procedures to eventually recover a second C&C machine. At a 12:30 p.m. news briefing, station flight director John Curry said it appeared C&C-2 was healthy. But around 1:30 p.m. - just minutes after the briefing ended - station astronaut James Voss reported half the lights in the Destiny laboratory module had suddenly gone out. A few moments later, astronaut Charlie Camarda in mission control reported "all indications appear we have good cooling, ventilation and power and the computers are OK. We still do not know why we went into (an electrical) load shed but we are checking that on the ground." Stay tuned. In the meantime, the astronauts are wrapping up work to unload an Italian cargo module docked to the station's Unity module. Astronaut Scott Parazynski, operating Endeavour's robot arm, likely will undock the module later today or early Friday and restow it in the shuttle's cargo bay for return to Earth. The other top priority of the mission is to complete delayed tests of the station's new Canadian-built robot arm. The arm can be operated with just a single C&C computer, but flight controllers want a backup on line in case of additional problems. As a result, additional arm work is off until Friday at the earliest. Mission managers are debating the possibility of extending Endeavour's flight one day to complete all of the crew's initial objectives. A decision is not expected before early Friday, after engineers have had more time to assess the health of the station's computer system. Shuttle flight director Phil Engelauf said Endeavour has enough supplies, fuel and electrical power to extend its mission by up to two full days. The Russians, meanwhile, are scheduled to launch a new Soyuz lifeboat spacecraft to the station Saturday. The ship's three-man crew, including U.S. millionaire space tourist Dennis Tito, is scheduled to dock Monday. Engelauf said if Endeavour's flight is extended one day, the Soyuz would still be able to take off on time. The only impact would be a short turnaround for the station's on-board crew. But a two-day mission extension for the shuttle would force the Russians to delay the Soyuz launch by at least one day. Engineers suspect a problem with the complex, inter-related software on board the station caused the computer problem that has disrupted the crew's schedule. Even though C&C-2 appeared to be working normally, the team decided not to immediately reload various software packages that might be suspect, including the new space crane's control software, programs that operate the station's main Ku-band antenna and others, on the assumption a bug somewhere in the code triggered the initial failures. Instead, engineers are studying the programs for signs of trouble and will reload them in an incremental fashion, after a second C&C computer is online and operational. The Mighty Mouse software that saved the day for the station crew is loaded on computers in the Unity module. Those computers were programmed to keep tabs on the operation of the command computers in the Destiny module as a last-ditch backup. If it ever discovered all three C&C machines were out of action, the node computer system was programmed to automatically launch a routine called Mighty Mouse. The Mighty Mouse program then would begin turning power to the C&C computers off and back on again to force one of the machines to reboot. 04:00 p.m., 04/26/01, Update: Unity computers drop off line Two computers in the space station's Unity module unexpectedly shut down today amid ongoing work to recover the use of command computers in the Destiny laboratory module. It was not immediately clear whether this latest computer glitch was the result of work to reconfigure the compuer system or whether it represented a fresh problem. Either way, harried flight controllers decided they needed more time to complete troubleshooting and computer reconfiguration work, telling the astronauts, in effect, to take the rest of the day off while they continue efforts on the ground to get a better handle on the situation. In short, the station is not yet out of the woods and it would appear te trouble affecting its computer system is not yet fully understood. The combined station-shuttle crews worked earlier today to finish loading an Italian cargo module with station trash and no-longer-needed equipment so the module could be undocked and reberthed in the shuttle Endeavour's cargo bay. But the station's main command and control - C&C - computers are needed to unlatch the Raffaello module from its docking port on the Unity module and flight controllers want to make sure the computer system is healthy and fully redudant before proceeding with normal operations. Depending on how the system behaves overnight, the astronauts could be cleared to remove Raffaello early Friday before pressing ahead with delayed work to checkout the station's new robot arm. But that, too, requires an operational C&C computer system and so far, flight controllers have not given the equipment and its software a clean bill of health. The two computers in Unity that went off line this afternoon were instrumental in getting one of the C&C computers in the Destiny module back in action overnight. Engineers were in the process of reconfiguring the Unity computers today when they suddenly dropped off line. 06:50 p.m., 04/26/01, Update: Shuttle mission extended one day NASA's mission management team met late today and decided to extend the shuttle Endeavour's mission by at least one day to give engineers additional time to troubleshoot ongoing computer problems aboard the international space station. Endeavour and its seven-man crew had been scheduled to undock Saturday morning for a landing back at the Kennedy Space Center around 10 a.m. Monday. Undocking now will slip to Sunday at least, giving the station crew just 16 hours or so to prepare for arrival of a Russian Soyuz spacecraft carrying two cosmonauts and U.S. millionaire space tourist Dennis Tito. As soon as the station's computer system is restored to normal operation, Endeavour's crew will use the shuttle's robot arm to undock the Italian Raffaello cargo module from the station's Unity module and mount it back in the orbiter's payload bay for return to Earth. Station astronaut Susan Helms then will use the newly installed Canadian-built robot arm to hand a 3,000-pound cargo pallet back to the shuttle's robot arm so it can be returned to Earth. Helms and crewmate James Voss then will put the arm through a series of delayed tests to make sure the $600 million space crane will be ready to install the station's main airlock during the next shuttle assembly flight in June. Assuming, of course, that engineers can get the station's computer system back in good health. "The MMT has met and we have extended the mission at least one more day," astronaut Cady Coleman radioed the shuttle crew from mission control "We do not at this time have a time for you that we're going to perform the MPLM (Raffaello) and SLP (cargo pallet) handoff activities. But as soon as we know that, we'll let you know, hopefully, when you get up in the morning. But if not, we think there are lots of things that you and the two crews can be doing to get the ISS into shape." "Yeah, Cady, we agree, we've been tagging up and they've got a lot of tasks lined up that we can help them with," replied Endeavour skipper Kent Rominger. "We've got plenty of work to keep us employed up here." "We copy, we think ISS is in a good config docked to shuttle there, it's a great time to be able tyo understand these kinds of problems and in the meantime, we get to put the ISS crew in much better shape before you leave," Coleman said. Ground engineers, meanwhile, continue efforts to revive two computers in the Unity module that shut down earlier today. Command and control computer No. 2 in the Destiny laboratory module continues to operate normally. Destiny's other two C&C machines are expected to remain out of action until the Unity computers are revived. 08:10 p.m., 04/26/01, Update: Shuttle flight extended two full days; computer troubleshooting strategy Revising an earlier decision to extend the shuttle Endeavour's flight by one day, NASA managers late today decided to extend the mission at least two days to give engineers more time to resolve ongoing computer problems hobbling the international outpost. The plan, if agreed to by the Russians, would delay launch of a Soyuz spacecraft carrying millionaire space tourist Dennis Tito by at least one day and possibly longer. "For folks who like to fly in space, I think I have what is good news for the Endeavour crew," astronaut Cady Coleman radioed from Houston shortly after 7 p.m. "We are going to stay docked another day, that would be two total, and plan on undocking on flight day 12 (Monday) and landing on flight day 14 (Wednesday). "That gives us some time to get our arms around our computer situation and really get a good look at what's going on before we decide to do MPLM and SLP ops," she told station astronaut Susan Helms and shuttle flier Chris Hadfield. Coleman was referring to delayed work to move a cargo module from the station to the shuttle's payload bay for return to Earth and additional work with the station's newly installed robot arm to hand a no-longer-needed cargo pallet to Endeavour's robot arm for reberthing in the ship's cargo bay. "Our plan presently is if we can get comfortable tomorrow we would do MPLM (cargo module) ops and the soonest we would do SSRMS (station arm) ops with the SLP (Spacelab Pallet) would be the next day after that," Coleman said. "Well, Chris is pretty happy," Helms replied. "And Alpha's pretty happy." "Well I should actually couch that with words that we are pending Russian concurrence, they would have to move their Soyuz launch," Coleman said. "And so we're looking for that concurrence and folks are working real hard to make sure everything is coordinated. But right now that's our plan." Tito and his two cosmonaut crewmates are scheduled for launch Saturday from the Baikonur Cosmodrome. It takes two days for a Soyuz to catch up with its target and docking was expected Monday morning. But under the current plan, Endeavour will not leave the station until Monday, which would prevent the Soyuz from making an on-time launch. That's because the Russian spacecraft would have to pass with 20 feet or so of the shuttle's vertical tail fin during final approach and it is not known how that might affect the ship's rendezvous radar, radios or other systems. The decision to extend Endeavour's mission was based on a desire to make absolutely sure the space station's computers can be restored to normal operation after a series of subtle glitches that crippled the outpost Tusday evening. Bill Gerstenmaier, deputy manager of the space station program at the Johnson Space Center in Houston, said the team has two goals: To restore computer redundancy before attempting to undock the Raffaello cargo module; and to gain additional run time on the computers to make sure the software will remain stable over the long haul. To recap the basic problem: As of 7:45 p.m., just one of the Destiny lab module's three command-and-control computers was operational. In addition, two computers in the Unity module were off line because of a timing synchronization problem. The two node computers, running an emergency program called Mighty Mouse, were responsible for getting C&C-2 back in operation in Destiny after all three of the station's command computers shut down in domino fashion Tuesday night and Wednesday. But C&C-2's input-output capability was deliberately inhibited while engineers studied the situation. As a result, the computer's internal clock got out of synch with clocks in the Unity computers. When engineers attempted to reboot the Unity machines this afternoon, they immediately shut down, believing their was a problem. Gerstenmaier said engineers have developed a plan to get the node computers and C&C-2 back in synch this evening. Assuming that work goes well, engineers will attempt to re-establish the station's S-band communications link in order to reprogram one of the two off-line command computers. All of that will take nine or 10 hours, Gerstenmaier said, assuming all goes well. The idea is to have two C&C computers on line and operational, along with both node computers, before allowing C&C-2 to drive the motorized bolts holding the Raffaello module in place. If the computer failed midway through that process, the backup C&C machine could take over. And if that computer failed, the node machines could step in. Once the cargo module is berthed, engineers will focus on gaining run time on the C&C computers to ensure they will continue working normally. The computer system is required to operate the station's new robot arm and if all goes well, the arm will be powered up Saturday to hand the cargo pallet back to Endeavour's robot arm. "We've got a large group of folks ... all around the coutnry that are working on these computer software issues," said flight director Wayne Hale. "It's a great challenge. We kind of wish we didn't have this kind of challenge but at the same time, the response has been great, everybody's been working very hard. We're going to resolve these little obstacles on the way to success and get the station all operational before we leave." If all goes well, that is. And so far, that's turned out to be a big if. =================================================================== Tito cleared for launch in last-minute compromise (04/27/01) 06:25 a.m., 04/27/01, Update: Computer reconfiguration nears completion; no word from Russians on requested Tito launch delay The international space station's one working command-and-control computer turned over control of the station's orientation to the shuttle Endeavour's computers early today as part of an ongoing procedure to revive Alpha's still-crippled computer system. While Endeavour works to boost the station's altitude by about two miles, the Destiny module's lone operational C&C computer - C&C-2 - will re resynched with its guidance and navigation system machines and engineers will press ahead with work to re-initialize one of the lab's other two C&C computers. The third C&C computer - C&C-1 - is believed to have a failed hard drive. It will be replaced with an identical computer that normally would be used to control scientific equipment in the Destiny lab module. Once all of that is done, the space station will have a fully operational computer system for the first time since Tuesday night when C&C-1 suddenly dropped off line, triggering a domino-like cascade of failures that crippled the complex. Because engineers do not yet know exactly what caused the initial failure, computers controlling laboratory experiments and the station's new Canadian robot arm will not be allowed to talk to the C&C machines until engineers verify their software is bug free. In Russia, meanwhile, ground crews are readying a Soyuz spacecraft for launch to the space station carrying two cosmonauts and millionaire space tourist Dennis Tito. Liftoff is scheduled for Saturday with a docking on Monday. NASA mission managers asked their Russian counterparts Thursday to delay the flight by one day, allowing the Endeavour astronauts to spend an extra two days docked to the station while ground engineers complete thorough tests of the station's computer system. As of 6 a.m. today, however, the Russians had not yet agreed to delay Tito's flight. NASA insiders say if the Russians fail to honor the request - which the U.S. agency considers essential to ensuring the long-term health of the outpost - already strained relations between the station partners will erode even more. In the meantime, Endeavour will remain docked to the station at least through Sunday morning, one day longer than originally planned. If the Russians agree to delay the Soyuz flight by one day, Endeavour will not undock until Monday. The three-seat Soyuz serves as the station crew's lifeboat. The Russian spacecraft are only certified for 180 days in orbit and the lifeboat currently attached, which was launched on Oct. 31, is at the end of its orbital lifetime. Tito and his two crewmates are known as a taxi flight crew. They will deliver a fresh Soyuz to the station, spend about a week on board the outpost and then return to Earth in the current return vehicle. At issue is whether the Russians will agree to put one more day of orbital life on the current Soyuz. But for Endeavour to remain docked for an additional two days, the Soyuz flight must slip. The Soyuz cannot dock to the station while the shuttle is attached because it would have to pass close to Endeavour's vertical tail fin on final approach and it's not known how that proximity might affect the Russian craft's radar and other systems. In the meantime, assuming the overall computer reconfiguration work goes well today, the Endeavour astronauts will demate the Raffaello cargo module around 2:41 p.m., using the shuttle's robot arm to place it back in Endeavour's cargo bay for return to Earth. At least two C&C computers must be operational before Raffaello can be undocked from the Unity module's downward-facing port. While a single computer can operate the motor-driven bolts holding the cargo module to the station, flight controllers want at least one operational backup in place in case additional problems crop up. Additional tests of the new Canadarm 2 space crane will be deferred until Saturday when station arm operator Susan Helms will hand a 3,000-pound cargo pallet back to the shuttle's robot arm for reberthing in Endeavour's payload bay. Helms then plans to put the arm through a dry run of procedures that will be needed in June to install the station's main airlock. The arm work also requires at least two operational C&C computers. The computer problems began Tuesday night when C&C-1 suddenly had problems accessing its internal hard drive and then crashed. C&C-2 took over but it, too, had hard drive problems and began acting erratically. Flight controllers then switched to C&C-3, which soon experienced similar problems and dropped off line, taking the station's main communications system down with it. The C&C computers provide critical telemetry to the ground and carry out the commands needed to reconfigure various space station systems. Working in the blind using backup communications paths, flight controllers finally managed to bring C&C-2 back on line late Wednesday. Forty minutes later, however, it shut down again. At that point, unknown to ground engineers, a program running in two computers inside the Unity node detected that all three C&C machines were down and automatically began cycling power on and off in a bid to force one of the computers to reboot. The so-called Mighty Mouse program worked, and C&C-2 rebooted from scratch using pristine software. Engineers spent the rest of the day Wednesday restoring communications, studying telemetry and developing a plan to revive the other computers. Overnight, engineers resynchronized the two node computers with C&C-2 and re-established the station's S-band communications system before handing attitude control over to the shuttle this morning.