STS-101 MISSION ARCHIVE (COMPLETE) Updated: 05/31/00 Space Station Assembly Mission 2A.2a By William Harwood CBS News/Kennedy Space Center The following copy originally was posted on the Current Mission space page at http://www.cbs.com/network/news/space/current.html. Comments, suggestions and corrections welcome! TABLE OF CONTENTS -NASA mulls plan to break station flight into two missions (01/05/00) -Shuttle mission needed to refurbish Russian module (01/10/00) -NASA presses ahead for station refurb mission (01/27/00) -Crew revised for shuttle mission (02/16/00) -Shuttle managers assess launch date revision (03/01/00) -Shuttle KU-band antenna damaged; impact assessed (03/06/00) -STS-101 countdown strategy (03/09/00) -Launch managers defer launch date decision (03/13/00) -Shuttle engine replacement ordered (03/15/00) -NASA assesses station-shuttle rendezvous profile (03/17/00) -NASA debates additional launch delay (03/23/00) -NASA tentatively retargets launch for April 24 (03/29/00) -Flight readiness review, practice countdown on tap (04/03/00) -NASA sets 'official' launch date; timeline updated (04/05/00) -Engineers assess problem with Atlantis's rudder (04/05/00) -Engineers expected to attempt rudder repair at launch pad (04/05/00) -Engineers begin work to replace rudder drive unit (04/12/00) -NASA updates flight plan, window; rudder unit installed (04/14/00) -Shuttle repair, retests, complete; flight plan updated (04/17/00) -NASA managers opt for shorter launch window (04/20/00) -Atlantis astronauts arrive for launch (04/21/00) -Mission timeline tweaked; weather 'go' for launch (04/22/00) -Weather worsens Tuesday; improves Wednesday (04/23/00) -Shuttle launch delayed by high crosswinds (04/24/00) -High winds force second shuttle launch delay (04/25/00) -Shuttle launch scrubbed by high winds in Africa (04/26/00) -Shuttle Atlantis reset for May 18 launch try (04/28/00) -NASA managers refine launch options (05/04/00) -Launch window refined; countdown options explained (05/05/00) -Rendezvous timeline refined (05/09/00) -Launch windows updated; no station rocket firings planned (05/09/00) -Launch window, timeline changes. Again. (05/11/00) -NASA revises mission flight plan (05/13/00) -Countdown begins for fourth launch try (05/15/00) -Shuttle crew awaits Atlas launch outcome (05/16/00) -Atlas launch delayed; shuttle slip expected (05/16/00) -Shuttle set for launch (05/17/00) -Shuttle Atlantis cleared for Friday launch try (05/18/00) -Shuttle Atlantis rockets into orbit (05/19/00) -Shuttle closes in on space station (05/20/00) -Astronauts dock with station; start repair spacewalk (05/21/00) -Spacewalk ends; astronauts enter station (05/22/00) -Station reboost begins; third battery changed out (05/23/00) -Batteries installed; technical issue resolved (05/24/00) -Astronauts wrap up repair work (05/25/00) -Astronauts finish repairs; undock from space station (05/26/00) -Crew gears up for entry (05/27/00) -Astronauts pack up for re-entry; weather 'iffy' (05/28/00) -Atlantis glides to smooth nighttime landing (05/29/00) =================================================================== NASA considers plan to break station logistics flight into two missions (01/05/00) With launch of the Russian service module on hold pending resolution of Proton rocket problems, NASA managers are considering a plan to break up the agency's next space station mission into two parts and to mount a quick-response mission in March or April to refurbish the station's aging Zarya module. The station currently consists of Zarya and a U.S. node called Unity that will serve as a gateway to future modules. Zarya, also known as the FGB, originally was certified by its builder, Krunichev, for on-orbit operations through March 2000. While the module undoubtedly will continue to operate beyond its certified lifetime, the spacecraft needs repairs before Krunichev will officially certify it for extended operations. As a result, NASA likely will break up its next space station mission, assembly flight 2A.2/STS-101, into two back-to-back flights, 2A.2A and 2A.2B, both of which will be launched on Atlantis and include at least some of the same crew members. The 2A.2A mission, which would retain the STS-101 shuttle designation, is targeted for launch no earlier than March 16, assuming NASA can complete on-going shuttle wiring repairs. The 2A.2B would become shuttle mission STS-106. The goal of the first flight would be to install a new battery and other electrical gear to restore Zarya's power system to good health. At present, four of its six on-board batteries are operating normally. One of the other two has a bad cell and the other has problems with associated circuitry. Along with refurbishing the power system, a spacewalk would be mounted to move a cargo boom from Zarya's hull to a stowage point on one of Unity's pressurized mating adaptors. This is get-ahead work to make sure service module thruster firings down the road do not impact the boom. One month after the service module is launched - at least eight weeks after 2A.2A's launch - Atlantis would take off again on mission 2A.2B/STS-106. The goal of this flight is to outfit the module and deliver supplies. Depending on how optimistic one is about the service module's eventual launch date, Atlantis's second flight could get underway as early as July 8. But it appears more likely the flight will slip into the fall timeframe when all is said and done. As of this writing, the launch schedule is in flux and launch dates are highly speculative. This page will be updated as more information becomes available. =================================================================== Shuttle mission needed to refurbish Russian module (01/10/00) Editor's Note... Portions of the following report were written by this writer for Space News magazine. While NASA continues to list March 16 as the target date for launch the shuttle Atlantis on a space station assembly mission, on-going work to fix numerous wiring defects almost certainly will push the flight into April. As of this writing, Atlantis is four to six weeks behind the March 16 target and shuttle managers at the Kennedy Space Center are assessing alternative processing strategies to reduce the turnaround time. NASA is particularly eager to get Atlantis off the ground as soon as possible to service a Russian space station module already in orbit. The international space station currently consists of a multi-hatch U.S. node called Unity and a propulsion and power module called Zarya, also known as the FGB, that was built by Krunichev under contract to NASA. Both were launched in late 1998. Atlantis originally was scheduled for takeoff one month after the Russian launch of the service module Zvezda atop a Russian Proton rocket. The service module will provide the space station's initial crew quarters and take over primary propulsion from the less capable Zarya module. Subsequent U.S. components cannot be launched until Zvezda is in orbit. But launch of the service module is now off until June at the earliest - and possibly until July or August - because of work to recover from two recent Proton launch failures. In the Jan. 10 issue of Space News magazine, a senior official at the Russian Aviation and Space Agency [Rosaviakosmos] said "We don't have a back-up module and, therefore, we will not launch the service module until we carry out all necessary ground tests of the rocket's engines to make sure they don't fail." The service module will not be committed to flight until at least three Protons have successfully flown. "All this makes us look at July or even August as the earliest possible" target date for launch, the Rosaviakosmos official told Space News. But that presents a problem for space station planners in both countries because Zarya's major components are only certified for operations through March. When Zarya was launched in November 1998, NASA and the Russians were confident the service module would be in orbit long before March 2000. But Russian funding problems delayed completion of the service module and the recent Proton failures have caused additional slippage. In the meantime, Zarya has started showing signs of wear and tear after a full year in orbit. Only four of its six batteries are working properly and while the module undoubtedly will continue operating past its certified lifetime, station planners want to ensure its health until the service module can be launched. Zarya's builder, the Krunichev company, has tentatively agreed to re-certify the module for operations through Dec. 31 if NASA launches a shuttle mission to repair the power system and to make other upgrades. "We're working on it right now," said Robert Cabana, a veteran shuttle commander who manages international operations for NASA's station program. "We're pressing ahead to put everything in place." NASA's next station assembly flight, a mission known as 2A.2, had been scheduled for launch one month after the service module reached orbit. The goal of the flight was to outfit the new module and to deliver supplies for the first full-time crew. It now appears NASA will break assembly flight 2A.2 into two back-to-back missions, both using the shuttle Atlantis and at least some of the same crew members. Contrary to recent news reports, some changes in Atlantis's current crew are expected. The first flight, which would be known as 2A.2A, would be launched as soon as possible. "The rationale is FGB lifetime extension," Cabana said in a Jan. 5 interview with Space News. "That's the real reason for this flight." Atlantis's crew would replace an 800-amp battery known to have a bad cell and install two current converters and a controller that would give Zarya a full complement of six operational batteries once again. Cabana said the astronauts also would replace a harmful contaminant filter cartridge, install a fan, a new smoke detector and a memory unit for the module's radio telemetry system. In addition, one spacewalk likely would be staged to move a cargo boom on Zarya's hull to another location to prevent thruster damage after the service module arrives. Under this scenario, Atlantis's second flight - 2A.2B - would not take off until one month after the service module's launch. As with the original 2A.2 flight, the second Atlantis mission would be devoted to outfitting the service module and delivering supplies. Assuming the service module does, in fact, slip to mid summer, launch of the first full-time station crew would be delayed to the October timeframe. Subsequent U.S. flights to deliver a truss element, solar arrays and the U.S. laboratory module would slip accordingly. =================================================================== NASA presses ahead for station refurb mission (01/27/00) NASA managers today formally agreed to press ahead with plans to launch a shuttle mission in April to refurbish the international space station's NASA-financed Russian-built Zarya module. Shuttle flight STS-101 originally was scheduled for launch about one month after delivery of a Russian service module to the station that is intended to provide propulsion and crew quarters. But launch of the service module is on hold pending resolution of problems with the Proton rocket needed to boost it into orbit. In the meantime, the Zarya module currently providing power and propulsion for the station has suffered a variety of problems. Based on the assumption the Russians will be unable to launch the service module before the end of June or July, NASA is now pressing ahead with plans to launch a Zarya servicing mission aboard shuttle Atlantis. The flight, known as shuttle mission STS-101 and station assembly flight 2A.2A, would take off around 8:44 p.m. on April 13 and return to Earth around 4:44 p.m. on April 23. Along with replacing a failed battery, the astronauts would install control equipment to restore a second battery to operation along with other equipment to improve fire detection, hazardous gas detection and communications with the ground. A spacewalk would be carried out on April 16 (see the next entry for details about the goals of this mission). "We have lost one battery and one electronics system that controls [another] battery, so effectively we have lost two batteries out of six on board the station," said station program manager Tommy Holloway. "So the primary driver is to replace the failed battery and the electronics system." If the service module is, in fact, delayed past June, NASA may elect to mount an additional mission to carry up hardware and equipment for the first crew, material originally bookmarked for the original STS-101 mission (assembly flight 2A.2). The new flight would be called STS-106/2A.2B and would be considered the second half of the original STS-101 mission. But if the Russians can launch the service module in late May or early June, NASA likely will scrub the planned April 13 mission and launch a single flight, STS-101, as originally planned one month after the Russian module reaches the station. Crew assignments for these scenarios have not yet been announced. Here are two near-term launch schedule possibilities based on when the service module is launched: Scenario 1: Service module launch in July or August 04/13/00...STS-101/2A.2A....Zarya refurbishment mission 07/??/00...Proton...........Service module 08/19/00...STS-106/2A.2B....Station outfitting mission 09/21/00...STS-92/3A........Z1 truss 11/??/00...Soyuz............First permanent crew is launched 11/30/00...STS-97/4A........Solar arrays 01/18/01...STS-98/5A........U.S. lab module Scenario 2: Service module launch in May 05/20/00...Proton...........Service module 06/22/00...STS-101/2A.2.....Station outfitting 07/20/00...STS-92/3A........Z1 truss 08/??/00...Soyuz............First permanent crew 08/24/00...STS-97/4A........Solar arrays 10/23/00...STS-98/5A........U.S. lab module 11/30/00...STS-102/5A.1.....Station outfitting Sources say the issue boils down to implementation of proposed modifications to increase reliability of the Proton rocket in the wake of two failures last year. NASA managers apparently want the Russians to stick with one set of already tested modifications and to launch the service module around May 20. The Russians are considering additional modifications that, if implemented, would push the launch into the July/August timeframe. "The Russians have finished their investigation and they are well into manufacturing certification and ground testing of a modification that should improve the robustness of the pump in question that was associated with the two accidents," Holloway said. "They currently are in the process of evaluating that, plus some proposed other mods, and I really think it would be inappropriate for me to talk a lot about the Russian technical problem." Even so, Holloway said, "we would like to launch the service module as soon as the Proton is ready to fly. If they could do that in April ... I would be delighted." "It appears, though, that April is not possible in terms of the mods they already have certified and ground tested," he went on. "It appears that might be possible later ... like in May or June. Or July. To go and make some additional mods still in the design phase is going to be longer and the Russians have said perhaps August, in fact. That's the date you hear in all the press releases out of Moscow. "The Russians are currently in a process of evaluating whether they would recommend that we launch on this engine that has been ground tested and certified or whether they would like to do additional mods." Assuming Atlantis takes off April 13, the earliest the orbiter could be turned around for the STS-106 mission would be Aug. 19. Shuttle planners are assessing whether STS-106 can be flown in July on a different orbiter, but that issue is unresolved. The preliminary STS-101/2A.2A flight plan has been posted below. It will undoubtedly change between now and flight, but it provides a useful overview of the mission as it is now envisioned. =================================================================== Crew revised for shuttle mission (02/16/00) NASA's latest internal space station assembly sequence - not yet formally approved - shows nine assembly flights this year: Four shuttle missions, launch of the Russian service module, three Russian Progress supply ships and launch of the first full-time crew aboard a Soyuz ferry craft. The preliminary manifest assumes the service module launches between July 8 and July 14, as proposed by the Russians in a Feb. 11 meeting in Moscow. Assuming that date holds up, NASA will stick with previously announced plans to split the next shuttle assembly mission STS-101/2A.2 into two parts - STS-101/2A.2a and STS-106/2A.2b - both aboard the shuttle Atlantis. The original STS-101/2A.2 crew will be split up for these two missions. While the new crews have not been announced, sources say the new STS-101 crew will be made up of: Commander: James Halsell Pilot: Scott Horowitz MS1: Mary Ellen Weber MS2/EV1: Jeffrey Williams MS3/EV2: James Voss MS4: Susan Helms MS5: Cosmonaut Yuri Usachev Halsell, Horowitz, Williams and Weber were assigned to the original STS-101 mission, along with Edward Lu and cosmonauts Yuri Malenchenko and Boris Morukov. It now appears Lu and the Russians will be assigned to the STS-106 mission, along with commander Terrence Wilcutt, pilot Scott Altman, Daniel Burbank and Richard Mastracchio. Voss, Helms and Usachev make up the station's second permanent crew, known as Expedition 2. They have been added to the STS-101 crew because of their familiarity with the Zarya module and their prior shuttle training (Voss and Helms are shuttle veterans). The goal of the STS-101 mission is to repair and refurbish the aging module because of delays getting the service module into orbit (see the next two entries for complete details). That said, here is the latest international space station assembly schedule: LAUNCH........FLIGHT...STS#......SHUTTLE......PAYLOAD 04/13/00......2A.2a....STS-101...Atlantis.....Zarya refurbishment 07/08-14/00...1R..............................Service module 07/31/00......1P..............................Progress supply ship 08/19/00......2A.2b....STS-106...Atlantis.....Station outfitting 09/14/00......2P..............................Progress supply ship 09/21/00......3A.......STS-92....Discovery....Z1 truss 10/30/00......2R..............................Increment 1 crew 11/30/00......4A.......STS-97....Endeavour....P6 solar array 12/12/00......3P..............................Progress supply ship 01/18/01......5A.......STS-98....Atlantis.....U.S. laboratory module 01/29/01......................................2R Soyuz move 02/01/01......4P..............................Progress supply ship 02/09/01......4R..............................Docking compartment 02/15/01......5A.1.....STS-102...Discovery....Lab outfitting 04/12/01......5P..............................Progress supply ship 04/19/01......6A.......STS-100...Endeavour....Station RMS; outfitting 05/01/01......2 Soyuz.........................Soyuz ferry flight 05/17/01......7A.......STS-104...Atlantis.....Airlock 06/30/01......6P..............................Progress supply ship 07/12/01......7A.1.....STS-105...Endeavour....Station outfitting 09/06/01......7P..............................Progress supply ship Readers should take this schedule with a large grain of salt. It reflects what NASA would like to see, but it's not yet official. =================================================================== Shuttle managers assess launch date revision (03/01/00) Launch of the shuttle Atlantis on a space station refurbishment and repair mission likely will slip a week or so beyond the currently advertised April 13 launch target. A commercial Atlas rocket carrying a Eutelsat communications satellite is scheduled for launch on the Air Force Eastern Range on April 14. The Eastern Range provides radar tracking, photo documentation and self destruct support for all rockets launched from Florida. Range customers are guaranteed two launch attempts and it typically takes two days to reconfigure the range to support a different rocket. Because of the range conflict and the time needed to complete shuttle launch preparations, Atlantis's flight likely will slip to April 18 or 19, agency officials say. The STS-101 flight plan below now reflects an April 18 launch date. The flight plan will be revised when a firm land date is set. =================================================================== Shuttle KU-band antenna damaged; engineers assessing impact (03/06/00) The shuttle Atlantis's KU-band television/radar antenna was damaged Sunday night when engineers were stowing it in preparation for payload bay door closing. Engineers had planned to move the shuttle from its processing hangar to the Vehicle Assembly Building on March 13 for work to prepare the ship for blastoff around April 18 on a space station repair mission. Rollover to the VAB will be delayed as a result of the antenna mishap, NASA officials said late Monday, but it's not yet clear what impact, if any, the work might have on Atlantis's eventual launch date. The KU-band antenna is used to send high-speed data and television to the ground during flight. It also acts as a radar dish during rendezvous operations. During launch, the black, 3-foot-wide graphite-epoxy dish and a support structure are stowed inside the cargo bay. Once the payload bay doors are opened in orbit, the dish's support platform swings out about 150 degrees. The antenna then targets one of NASA's communications satellites. A senior NASA manager said the dish was damaged Sunday evening during work to ready Atlantis for payload bay door closing. As the dish was nearing the end of its 150-degree rotation, it ran into a bridge crane work platform used to give technicians access to the area. United Space Alliance, NASA's prime shuttle contractor, was in charge of the operation. "At the very end of the antenna, from the picture I've seen, it looked to me about a one inch by two inch - maybe one inch by one inch, it was hard to tell - about that much material was displaced," the NASA manager said. After assessing a variety of options Monday, engineers decided to repair the antenna in place rather than replace it. How much of that work can be carried to the launch pad is not yet known. =================================================================== STS-101 countdown strategy (03/09/00) NASA managers meeting Friday are expected to target April 17 for launch of the shuttle Atlantis on a space station repair mission. Engineers plan to move the shuttle from its processing hangar to the Vehicle Assembly Building on March 16 where it will be attached to an external tank and a set of solid-fuel boosters. If all goes well, the shuttle stack will be rolled out to pad 39A on March 21 for a launch attempt on Monday, April 17, around 7:03 p.m. A commercial Lockheed Martin Atlas 3R rocket - the first equipped with a Russian first-stage engine - has reserved the Air Force Eastern Range for a launch attempt on April 14. Lockheed Martin will be able to make two launch attempts between April 14 and 16. If the flight takes off on April 14 or 15, Atlantis will be cleared for a launch attempt on April 17. If the Atlas fails to get off on April 14 and recycles for a 48-hour delay, the shuttle launch will slip one day to April 18 at 6:40 p.m. Either way, Atlantis's international crew plans to fly to the Kennedy Space Center on April 14 (exact time TBD) for the start of the shuttle's countdown at 10 p.m. that evening. If the Atlas fails to get off the ground that night and slips 48 hours to April 16, NASA will insert a 24-hour hold in the shuttle's countdown at the T-minus 27-hour mark at 2 p.m. on April 15. The countdown would resume at 2 p.m. on April 16 with loading of fuel for the shuttle's electrical generators. Otherwise, the countdown will continue uninterrupted for a launch on April 17. As usual with space station countdowns and short launch windows, the final hold at T-minus nine minutes will last 40 minutes instead of 10 minutes to provide additional time to resolve any last-second problems. In addition, a hold at the T-minus six-hour mark prior to the start of fueling will last two hours. Here are all the hold times for an April 17 launch: DATE/TIME......EVENT 04/14 09:00 a.m......Countdown status briefing on NASA television TBD............Crew arrival 10:00 p.m......Countdown begins 04/15 09:00 a.m......Countdown status briefing 02:00 p.m......Start a four-hour hold at T-minus 27 hours 04:00 p.m......Pre-launch news conference 06:00 p.m......Countdown resumes; begin fuel loading for shuttle electrical generators 04/16 02:00 a.m......Start a four-hour hold at T-minus 19 hours 06:00 a.m......Countdown resumes with main engine preps 09:00 a.m......Countdown status briefing 10:00 a.m......Space station status briefing 02:00 p.m......Start a 13-hour 13-minute hold at T-minus 11 hours; comm system activation; RSS retraction 04/17 03:13 a.m......Countdown resumes 08:13 a.m......Start a two-hour hold at T-minus six hours; managers give go/no-go for fueling 10:13 a.m......Countdown resumes; fuel loading begins 12:08 p.m......Shuttle fueling complete; tank in stable replenish 01:13 p.m......Start a two-hour hold at T-minus three hours 03:13 p.m......Resume countdown 05:53 p.m......Start a 10-minute hold at T-minus 20 minutes 06:03 p.m......Resume countdown 06:14 p.m......Start a 40-minute hold at T-minus nine minutes 06:54 p.m......Resume countdown 07:03 p.m......Launch Finally, a note about launch windows. If Atlantis takes off on April 17, the crew will rendezvous and dock with the international space station on flight day 3. If launch slips to April 18, docking would occur during flight day four. The launch window for April 19 supports a docking on either flight day 3 or 4. In that case, NASA would target liftoff within the available window to ensure a flight day 3 rendezvous. Additional countdown details, including pre-launch crew events, will be posted here as soon as they are available. =================================================================== Launch managers defer launch date decision (03/13/00) NASA managers Friday deferred setting a new target launch date for shuttle mission STS-101. But, as reported below, April 17 remains the agency's internal planning date. This status report will be updated when any decision, one way or the other, is made. =================================================================== Shuttle engine replacement ordered (03/15/00) NASA managers have ordered engineers to replace one of the shuttle Atlantis's three main engines - SSME No. 1 (serial number 2045-2A) - because of concern about the health of tip seals in the powerplant's high pressure hydrogen fuel pump. It's not yet clear whether or not the engine changeout will affect Atlantis's launch, which currently is targeted for April 17. At this point, however, any impact is expected to be minor. Atlantis is scheduled to be moved from its processing hangar to the Vehicle Assembly Building early Thursday for attachment to an external fuel tank and a set of solid-fuel boosters. Engineers are assessing whether main engine No. 1 can be replaced in the VAB or whether the work will have to be done at pad 39A. No engine in the No. 1 position - directly under the shuttle's vertical stabilizer - has been replaced in the VAB since implementation of government safety rules that make access to that area difficult. The work can be done at the launch pad, but weather and other factors can affect how long it takes. If the engine is, in fact, replaced in the VAB, rollout to the pad likely would slip from March 21 to March 24, leaving two days of on-pad contingency time for a launch attempt on April 17. "It's easier in the VAB for a lot of reasons," said a senior NASA manager. "But the only real impact at the pad is it would take a little longer and you're a little more subject to weather and the potential impact of high winds and things. But at most, all it would cost you is a little contingency." Each main engine fuel pump contains two six-segment nickel-alloy tip seals that run around the interior of the housing in line with two turbine blade wheels. The seals ensure that all the hot gas entering the pump turbine actually hits the turbine blades used to drive the machinery. There is an 18-thousandths-of-an-inch gap between the seals and the tips of the turbine blades attached to the two wheels. After launch of the shuttle Discovery in December, engineers discovered a seal segment with significant delamination. As it turned out, the component in question was a factory reject that never should have been installed in an engine in the first place. A fleet-wide paperwork review was ordered to locate any other such suspect tip seal segments. In the absence of paperwork confirming a segment's pedigree, shuttle program manager Ron Dittemore said engineers would rely on engineering analysis based on past performance and other factors to decide whether a suspect segment is safe for flight or not. The shuttle Endeavour was cleared for launch Feb. 11 with two such tip seal segments in place. Paperwork later was found for one of them. It is not yet known what the issue is with Atlantis's No. 1 main engine. This status report will be updated when additional information is available. =================================================================== NASA assesses station-shuttle rendezvous profile (03/17/00) Flight controllers at the Johnson Space Center in Houston are struggling to determine the effects of recent and predicted solar flare activity on Earth's upper atmosphere and, consequently, the international space station's orbit. Predicted orbital parameters for April 17 - the day NASA hopes to launch the shuttle Atlantis on a station repair mission - appear to favor a flight-day-four rendezvous with the space station, not a flight-day-three opportunity as originally planned. If it turns out a flight-day-four rendezvous is the only option for an April 17 launch, NASA managers may elect to delay the flight a day to get a flight-day-three opportunity. As of this writing, it appears even launch dates favor FD-3 opportunities while odd dates favor FD-4 dockings. An FD-4 rendezvous likely would require NASA to extend the mission a day to accomplish all of the repair and refurbishment work currently planned. The STS-101 flight plan (and the flight plan available in SpaceCalc assume a flight-day-three rendezvous and docking. Both will be updated as warranted when the rendezvous profile firms up. Atlantis's crew originally planned to replace one of the Russian Zarya module's six batteries, along with electronic control equipment used to operate another. As it now stands, the astronauts will replace at least four batteries outright and refurbish Zarya's ventilation, fire suppression and air filtration system as originally planned. They also will deliver supplies that ultimately will be used by the station's first full-time crew later this year. At the Kennedy Space Center, meanwhile, engineers are gearing up to replace one of Atlantis's three main engines - SSME No. 1 - inside the Vehicle Assembly Building. The engine's high pressure hydrogen turbopump contains tip seal components of suspect heritage (see next entry for details). Engineers initially thought the replacement work would have to be done at the launch pad, but that turned out not to be the case. Rollout to pad 39A is targeted for March 24. =================================================================== NASA debates additional launch delay (03/23/00) NASA managers have rescheduled the shuttle Atlantis's dress rehearsal countdown, moving it from next week to April 5, 6 and 7. Launch on a space station repair mission, which had been targeted for April 17, will slip at least one day, to 6:37:18 p.m. on April 18. Officials say additional slippage is likely because of crew training issues, normal launch processing and work to fix suspect TV camera pan-and-tilt mounts in the shuttle's cargo bay. Agency insiders believe launch could end up slipping to April 25 or 26 when all is said and done. A decision is expected early next week. Contrary to widespread rumors, however, shuttle commander James Halsell's sprained ankle will not have any impact on Atlantis's eventual launch date. Halsell twisted his ankle last week in one of NASA's fixed-base shuttle simulators at the Johnson Space Center in Houston. But the injury is considered minor and no threat to Atlantis's launch. Atlantis is scheduled to be moved from the Vehicle Assembly Building to pad 39A on Saturday. The terminal countdown demonstration test, or TCDT - emergency egress training and a simulated countdown - is scheduled to begin April 6. In the meantime, flight dynamics officers at the Johnson Space Center continue to refine rendezvous scenarios for Atlantis's flight to the international space station. As mentioned earlier, even launch dates favor a rendezvous on flight day three - NASA's preferred option - while odd launch dates favor a flight-day-four rendezvous. Updated STS-101 launch windows, through April 27, have been posted, along with an updated STS-101 flight plan reflecting a launch on April 18. SpaceCalc will be updated next week, after the launch date firms up a bit more. =================================================================== NASA tentatively retargets launch for April 24 (03/29/00) After meetings with the Air Force Eastern Range, NASA managers today tentatively retargeted the shuttle Atlantis's launch on a space station repair mission for April 24. While an exact launch time is not yet available, liftoff from pad 39A will occur around 4:15 p.m. Assuming the schedule holds up, Atlantis would dock with the international space station the morning of April 26 and a spacewalk would be carried out the next day. Undocking would occur before dawn on May 2 with landing on tap May 4. Shuttle mission STS-101 had been targeted for April 17. But two weeks ago, commander James Halsell sprained his ankle in a fixed-based simulator at the Johnson Space Center. While he said Monday he would have been medically fit to fly as early as April 17, he would not have been able to participate in a launch pad escape drill during the crew's terminal countdown demonstration test, which had been scheduled for this week. But shuttle planners decided to reschedule the TCDT for April 6 and 7 so Halsell could fully participate. At the same time, launch slipped one day to April 18 while NASA managers assessed their options. The Air Force Eastern Range provides radar tracking, self-destruct services and photo documentation for all rockets launched from the East Coast. Each Range "customer" typically gets two back-to-back launch opportunities and it takes two days to reconfigure range equipment to support a different launch. A Lockheed Martin Atlas 3 rocket carrying a commercial communications satellite is scheduled for takeoff April 14 and a Delta-2 carrying a GPS navigation satellite is set for launch April 21. An Air Force Titan 4B rocket with a missile warning satellite on board is targeted for launch on May 8. NASA managers had hoped to avoid a countdown over the Easter weekend, but in the end they had to settle for April 24, 25 and 26. If Atlantis is not off the ground by April 26, the flight will slip to at least May 11. The April 24 launch target will be re-assessed at the STS-101 flight readiness review next Tuesday and Wednesday. As mentioned in earlier status reports, even launch dates favor a flight-day-three rendezvous with the international space station while odd launch dates favor a rendezvous on flight day four. As it now stands, that's the scenario NASA will face for launch during the April 24-26 window. Agency managers want a flight-day-three rendezvous if at all possible. A flight-day-four mission would require the crew to extend the mission by one day just to complete all their planned tasks. For an FD-3 case, the crew could add a bonus day of docked activity if necessary, an option not available if docking is delayed a day. An updated STS-101 flight plan based on an April 24 liftoff has been posted along with an updated edition of SpaceCalc (revision E). NOTE: The flight plan has not yet been finalized and readers can expect the version posted below to change in the days ahead. The final version will be posted here as soon as it is available. =================================================================== Flight readiness review, practice countdown on tap (04/03/00) NASA managers begin a two-day flight readiness review Tuesday, April 4, to assess the shuttle Atlantis's readiness for blastoff on a mission to repair and service the interantional space station. Barring some unexpected issue, NASA managers are expected to approve the current April 24 target launch date when the FRR concludes Wednesday. Atlantis's international crew flies to the Kennedy Space Center on Wednesday to participate in a terminal countdown demonstration test, or TCDT, Thursday and Friday. The astronauts will practice launch pad emergency escape procedures Thursday and field questions from reporters at the base of pad 39A. All seven crew members will strap in aboard Atlantis on Friday morning for a dress rehearsal countdown. =================================================================== NASA sets 'official' launch date; major event times updated (04/05/00) NASA managers completed a two-day flight readiness review today, setting April 24 as the official launch date for the shuttle Atlantis's space station repair mission. Setting the stage for liftoff, the shuttle's seven-member crew will review launch pad emergency escape procedures Thursday before strapping in Friday for a dress-rehearsal countdown. Commander James Halsell and his crew will be making the first flight aboard a shuttle equipped with state-of-the-art "glass cockpit" computer displays and instruments. "Atlantis's last flight in space was a visit to the Mir space station," shuttle program manager Ron Dittemore said in a statement. "Since then, Atlantis has had more than 100 modifications and improvements made, making it the most up-to-date shuttle ever." At the Johnson Space Center in Houston, meanwhile, flight controllers are refining their launch window estimates and the timing of major mission events based on the latest forecasts for the international space station's orbit. Updated launch windows through May 3 have been posted below. The "planar" launch window for April 24 actually opens at 4:12:21 p.m. But the preferred launch time, based on vehicle performance, is 4:14:50 p.m. The five-minute "performance window" closes at 4:19:50 p.m. The overall planar window closes at 4:22:20 p.m. Assuming an on-time liftoff at the opening of the performance window, Atlantis commander James Halsell would fire the shuttle's maneuvering jets to begin the terminal phase of the space station rendezvous (TI burn) at 5:56 a.m. on April 26 (MET: 1/13:40:46) and docking would occur at 9:15 a.m. (MET: 1/17:00). As with the earlier versions of the flight plan, a spacewalk by Jeffrey Williams and James Voss would begin at 7:45 a.m. on April 27 and end around 1:45 p.m. Space station ingress would be targeted for around 5;30 a.m. the next day. Undocking is now targeted for 4:07 a.m. on May 2 (MET: 7/11:52:21). Deorbit ignition to drop Atlantis out of orbit is planned for 10:19 a.m. on May 4 (MET: 9/18:4:23) for a landing back at the Kennedy Space Center at 11:23 a.m. (MET: 9/19:08). While the times for major events are firming up, flight planners continue to massage Atlantis's detailed flight plan and a final version is not expected until next week. The STS-101 flight plan posted here includes the updated mission times listed above, but the timing of other events is not yet known. As such, readers should use the current flight plan for guidance only, not for detailed planning. An updated flight plan will be posted as soon as it is available. =================================================================== Engineers assess possible problem with Atlantis's rudder/speed brake (04/05/00) At almost the same time NASA managers today were setting April 24 as the official launch date for shuttle Atlantis on a space station repair mission, engineers were running into a potentially significant problem with the spacecraft's dual-function rudder/speed brake, sources say. During a test of the rudder's actuator system at launch pad 39A late today, engineers saw pressure readings of some 1,200 pounds per square inch instead of 400 psi as expected. A senior shuttle engineer said the rudder's power drive unit, or PDU, likely will have to be replaced. But it's not yet clear whether the PDU can be replaced at the launch pad with Atlantis in a vertical orientation. If the shuttle must be hauled back to its processing hangar for repairs, launch probably would be delayed two weeks or longer. But that is strictly a worst-case scenario and engineers may, in fact, be able to make repairs - if needed - at the launch pad. But they will have to be quick. NASA only has three days to launch Atlantis - April 24, 25 and 26 - before losing Air Force Eastern Range support until mid May. The Eastern Range provides radar tracking, photo documentation and self-destruct functions for all rockets launched from Florida. If Atlantis is not off the ground by April 26, the flight likely would slip to around May 11, after two military operations - a Titan 4 test and another classified operation - launch of NOAA's latest GOES weather satellite on May 3 and launch of a missile early warning satellite aboard a Titan 4B rocket on May 8. It typically takes two days to reconfigure the range to support another rocket launch and the next available slot for the shuttle comes on May 11, 12 and 13. After that, a Lockheed Martin Atlas 3 rocket has the range booked to launch a Eutelsat communications satellite on May 15. All of that is worst case, of course, and the shuttle's rudder/speedbrake problem may end up going away or proving fixable at the pad in time to make an on-time April 24 launch attempt. But until this issue is resolved, readers should be aware of several issues involving Atlantis's launch date and the orbit of the international space station. The space station currently is losing about 1.5 statute miles of altitude per week due to atmospheric drag, a braking effect produced by the spacecraft's passage through the extreme upper atmosphere at a relatively low altitude. Atlantis's crew plans to use the shuttle's maneuvering jets to boost the station's altitude by some 19 miles during the upcoming mission, using about 1,200 pounds of propellant. Three reboost rocket firings will be required. NASA originally planned to boost the station's altitude by much less than that with a single set of rocket firings. But that was before Atlantis's flight slipped from March to April and before strong solar activity acted to increase the effects of atmospheric drag. If Atlantis's launch is delayed past the second week in May, NASA and the Russian Space Agency likely will be forced to boost the station's altitude by using the Russian Zarya module's maneuvering engines, burning up precious on-board fuel in the process. While that is not a problem per se, flight controllers want to protect the station's on-board fuel supplies as much as possible until launch of the Russian service module in July. The refuelable service module then will take over the station's propulsion chores. Again, this may all be a moot point. But given all the issues in play, this page will err on the side of caution. Stay tuned! =================================================================== Engineers expected to attempt rudder repair at launch pad (04/05/00) Faced with a possible two- to three-week launch delay, engineers are expected to make an attempt next week at pad 39A to replace a suspect rudder power unit aboard the shuttle Atlantis to avoid a possible rollback to the hangar for repairs. The problem was discovered Wednesday after routine work to ready Atlantis for blastoff April 24 on a space station repair mission (see the previous CBS News status report immediately below for additional details). Replacing the power drive unit, or PDU, is not difficult in and of itself. But engineers must prevent air getting from into the shuttle's hydraulic lines during the swap out. If any air makes its way into the system - and nothing like this has ever been attempted with the shuttle in a vertical orientation - Atlantis would have to be hauled back to its processing hangar for hydraulic servicing. If a rollback ultimately is required, launch would be delayed to mid May at the earliest and possibly longer. The PDU swap out at pad 39B will begin early next week. Engineers have five days of contingency time left in Atlantis's processing schedule and if no problems develop with the hydraulic system, the shuttle could still make its April 24 launch date. Atlantis must be off the ground by April 26, however, or the flight will slip to mid May anyway because of conflicts with other upcoming rocket launches. As outlined in the the previous CBS News status report, Atlantis is needed to reboost the international space station's altitude. Because of recent solar activity, the space station is losing about 1.5 statute miles of altitude each week. If Atlantis's launch is delayed to mid May, flight controllers would be forced to reboost the station using precious propellant in the Russian Zarya module. =================================================================== Engineers begin work to replace rudder drive unit (04/12/00) With launch targeted for April 24, work to replace a faulty power drive unit used by the shuttle Atlantis's rudder/speedbrake got underway today at launch pad 39A. While engineers are increasingly confident the repair work can be completed successfully at the launch pad, it is not yet clear whether NASA can meet its April 24 launch target. Even if the PDU replacement goes smoothly, a leaking quick-disconnect fitting on one of the shuttle's three hydraulic power units, or APUs, must be replaced and the system then must be re-tested. The launch window for shuttle mission STS-101 opens on April 24 and closes on April 26. Engineers say privately April 24 will be difficult if not impossible to meet because of the PDU repair work and the APU hot fire test. But they are optimistic about getting at least one if not two shots at launching Atlantis by April 26. If any additional, significant problems crop up, launch likely would slip to mid May because of conflicts with other rocket launches already booked on the Air Force Eastern Range. The PDU replacement is an especially challenging procedure because of the unit's location in the shuttle's tail assembly, its weight - 350 pounds - and the threat of introducing air into Atlantis's hydraulic system. Earlier today, liquid nitrogen was used to freeze the hydraulic fluid in lines leading to the PDU. The lines then were disconnected and capped. By freezing the lines, engineers hope to prevent any air from getting into the hydraulic system, a problem that could not be corrected at the launch pad. If that happened, Atlantis would have to be hauled back to its processing hangar to "bleed" the lines and launch would be delayed several weeks. But NASA managers are increasingly confident that will not be required. Work to actually remove the old PDU was delayed several hours today but engineers hope to complete the job overnight if at all possible. In the meantime, troubleshooters are assessing what impact, if any, a dented liquid hydrogen line discovered in the shuttle's aft engine compartment might have. This is an unrelated issue and as of this writing, it's not known which line is dented, whether the damage is serious enough to require repairs or how long such repairs might take. At the Johnson Space Center in Houston, meanwhile, flight planners are continuing to refine the crew's flight plan. An updated version of the flight plan will be posted later this evening or early Thursday. =================================================================== NASA updates flight plan, launch window; rudder drive unit installed (04/14/00) Engineers have completed installation of a replacement rudder/speedbrake power drive unit in the shuttle Atlantis's tail section and if all goes well, testing should be complete by late Saturday. Engineers plan to test fire one of the shuttle's hydraulic power units Sunday before resuming normal pre-launch processing. See the latest NASA status report for additional details. If no additional problems develop, engineers say Atlantis can still make its planned April 24 launch date to kick off a mission to repair and refurbish the international space station. But there is no contingency time left in the processing flow to handle unexpected problems. Recent solar activity, which affects the extreme upper atmosphere and the orbits of low-altitude spacecraft, has made it difficult to accurately predict the space station's orbit and thus the timing of critical mission events. The shuttle's launch window actually opens at 4:12 p.m. and closes at 4:22 p.m. But based on shuttle performance, the preferred launch time remains 4:15 p.m. Here are the latest numbers: TIME............EVENT 04/24/00 04:12:23 p.m....Planar launch window opens 04:14:52 p.m....Performance launch window opens 04:17:22 p.m....The pad rotates into the station's orbital plane 04:19:52 p.m....The performance window closes 04:22:22 p.m....The planar window closes Assuming Atlantis launches at the opening of the "performance" window, the shuttle will dock with the space station at 9:09 a.m. on April 26. A spacewalk to install a crane, a new antenna and other equipment would begin at 7:50 a.m. on April 27 and the astronauts would enter the space station at 5:30 a.m. the next day. Undocking would be targeted for 3:59 a.m. on May 2 with landing on tap at 12:51 p.m. on May 4. Readers should take all these numbers with several grains of salt. They likely will change slightly between now and launch. Even so, the latest version of the STS-101 flight plan has been posted along with anupdated countdown timeline that includes crew activities at the Cape. =================================================================== Shuttle repair work, retests, complete; flight plan updated (04/17/00) Engineers have completed replacement and retest of a suspect rudder drive unit aboard shuttle Atlantis. The 350-pound component was installed last week and successfully checked out during a "frequency response test" Saturday at pad 39A. The FRT went well and the next day, engineers hot fired one of Atlantis's three hydraulic power units after replacing a leaking hose. Again, no problems were encountered. Assuming nothing else crops up, NASA should have a shot at launching Atlantis next week - at 4:15 p.m. April 24 - on a long-awaited space station repair mission. Commander James Halsell and his crew are scheduled to arrive in Florida around 2 p.m. Friday for the 7 p.m. start of Atlantis's countdown to blastoff. The only issue that remains to be resolved is confirmation the problem with Atlantis's original rudder/speedbrake power drive unit, or PDU, is not a generic issue that could affect similar units across the shuttle fleet. A meeting is scheduled tomorrow to discuss the issue. But as of this writing, most insiders expect Atlantis to be cleared for launch on April 24. In the meantime, mission planners at the Johnson Space Center in Houston have released yet another update to the crew's flight plan. The latest version shows Atlantis docking with the international space station at 10:36 a.m. on April 26, one orbit later than had been planned. =================================================================== NASA managers opt for shorter launch window (04/20/00) NASA managers have decided to restrict the shuttle Atlantis to a five-minute launch window - down from 10 minutes - in a bid to save as much fuel as possible to reboost the slowly-but-steadily falling international space station. Atlantis is scheduled for liftoff Monday at 4:14:54 p.m. on a mission to repair and refurbish the unfinished lab complex. To catch up with the station, the shuttle must launch roughly into the plane of the target's orbit. On April 24, Earth's rotation will carry launch pad 39A into the plane of the station's orbit at around 4:17:24 pm. But Atlantis has enough power to match orbits five minutes to either side of that ideal target. This so-called "planar" launch window will open at 4:12:33 p.m. Monday and close at 4:22:33 p.m. But recent solar activity has caused Earth's atmosphere to balloon out slightly, increasing the drag exerienced by satellites in low-Earth orbit. The space station has been falling about a mile and a half per week and NASA managers want to reboost the lab's altitude using shuttle propellant - not the station's precious on-board fuel - if at all possible. By reducing Atlantis's launch window by five minutes, the shuttle crew can save enough propellant to reboost the station by up to 19 miles. So even though Atlantis's theoretical launch window will open at 4:12:33 p.m. Monday, the countdown will be targeted for a launch around 4:14:54 p.m., the opening of the five-minute "performance window." The precise launch time will be determined during a final 40-minute hold at the T-minus nine-minute mark. A similar launch window philosphy will be in place during subsequent launch attempts Tuesday and Wednesday, if necessary. =================================================================== Atlantis astronauts arrive for launch (04/21/00) The shuttle Atlantis's countdown to blastoff is scheduled to begin at 7 p.m. and NASA managers say all systems are "go" for a launch attempt at 4:15 p.m. Monday. There are no technical problems of any significance at pad 39A and forecasters are predicting a 70 percent chance of good weather during Atlantis's five-minute launch window. "The team has worked extremely hard," said NASA test director Steve Altemus. "It's been a long flow. Everybody's geared up and really excited about coming out and launching on Monday." Atlantis's five-man two-woman crew arrived at the Kennedy Space Center shortly after 3:30 p.m. to prepare for launch on the 98th shuttle mission. "We are incredibly happy to be here at the Kennedy Space Station and getting ready for the space launch on Monday," commander James Halsell told reporters. "It's our understanding the vehicle's in fine shape and the processing is coming along on schedule. [Our] arrival at the Kennedy Space Center marks the real beginning of the space flight. We've been training every day, long hours, at the Johnson Space Centyer and the now the opportunity to come here to Kennedy to relax here for a couple of days while the processing finishes up and to man the vehicle and go fly the mission, today really marks the beginning of the space flight." Crewmate Mary Ellen Weber said the mission to repair and refurbish the international spae station was a "dream flight for a lot of us." "We have just had a tremendous time training together over the last number of months," she said. "We're ready to go and we're looking forward to being a part of this next step forward, and that is, the international space station." NASA's initial television schedule for this mission is available online and will be posted below as soon as possible. A CBS News sidebar on the shuttle's new state-of-the-art "glass cockpit" that was inadvertently left off this page Thursday is available immediately below the mission preview story. =================================================================== Flight controllers tweak mission timeline; weather 'go' for launch (04/22/00) Flight controllers in Houston have updated the shuttle Atlantis's space station rendezvous timeline based on the latest radar tracking, estimates of the propellant required to reboost the station's altitude and other factors. The shuttle's five-minute launch window will o pen at 4:14:56 p.m. - two seconds later than the previous estimate - and close at 4:19:56 p.m. Forecasters are predicting a 70 percent chance of good weather Monday afternoon. Additional launch opportunities are available Tuesday and Wednesday, although the weather is expected to deteriorate as the week wears on. "We're not working any issues or concerns," said NASA test director Doug Lyons. "The flight and ground systems are in great shape and the shuttle team's looking forward to a successful launch." Assuming an on-time liftoff, Atlantis's crew will begin the final phase of the space station rendezvous at 7:11 a.m. on Wednesday for a docking at 10:37 a.m. Here are the updated numbers (included in the The STS-101 flight plan below): TIME.........EVENT 04/24 04:15 p.m....Launch 04:59 p.m....OMS-2 orbit circularization burn (altitude: 175/171 nm) 07:58 p.m....NC-1 rendezvous rocket firing 04/25 07:56 p.m....NC-2 rendezvous rocket firing 04:38 p.m....The Mir space station passes within 81 miles of Atlantis 04:50 p.m....NC-3 rendezvous rocket firing 04/26 01:44 a.m....The Mir space station passes within 20 miles of the ISS 05:39 a.m....NC-4 rendezvous rocket firing 07:11 a.m....TI rendezvous rocket fing 10:37 a.m....Atlantis docks with the ISS (altitude: 190/178 nm) 04/27 07:50 a.m....Space station servicing spacewalk begins 02:05 p.m....Spacewalk ends 04/28 05:30 a.m....Space station ingress 04/29 04:45 a.m....ISS reboost 1 start 05:44 a.m....ISS reboost 1 stop 04/30 06:20 a.m....ISS reboost 2 start 07:19 a.m....ISS reboost 2 stop 05/01 05:45 a.m....ISS reboost 3 start 06:07 a.m....ISS reboost 3 stop 11:40 a.m....Space station egress 05/02 03:54 a.m....Atlantis undocks from the station 05/04 11:41 a.m....Deorbit ignition 12:44 a.m....Landing Due to an oversight, the latest editions of the STS-101 Mission and Quick-Look supplements to the CBS News Space Reporter's Handbook were not posted earlier this week as expected. Both are now available. In addition, the ascent events summary has been updated with the latest data from NASA. =================================================================== Weather worsens Tuesday; improves Wednesday (04/23/00) The shuttle Atlantis's countdown continues to tick smoothly toward blastoff Monday at 4:15 p.m. on a mission to repair and refurbish the international space station. Technicians began final main engine preps early this morning, followed by tests of the orbiter's avionics systems, seat installation and work to prepare critical launch pad systems for fueling Monday. Commander James Halsell and pilot Scott Horowitz spent Easter morning practicing landing procesures in NASA business jets modified to handle like a space shuttle on final approach. There are no problems of any significance at pad 39A and forecasters continue to predict a 70 percent chance of acceptable weather during Atlantis's five-minute launch window Monday afternoon. But if launch slips a day, the forecast calls for a 60 percent chance of a delay Tuesday due to high winds and possible thunderstorms associated with a low pressure system north of the Kennedy Space Center. The forecast for Wednesday calls for an 80 percent chance of good weather. NASA managers normally permit two launch attempts in a row before giving ground crews a day off to rest. But they may elect to make three tries in a row this time around - Monday, Tuesday and Wednesday - to maximize the chances of getting Atlantis's space station repair mission off the ground this week. If the shuttle isn't off by Wednesday, the flight could be delayed to May 11 because of conflicts with other rockets that share Air Force Eastern Range tracking systems. Even so, it's not an open-and-shut case. If Atlantis launches Monday or Wednesday, the crew can dock with the space station on flight day three. If they launch on Tuesday, they would have to dock on flight day four. Even with a flight-day-three rendezvous, NASA managers may be forced to extend the mission one day to give the astronauts time to complete all of their planned tasks. With a flight-day-four rendezvous, that is not an option and as a result, managers could elect to skip a Tuesday launch try if Atlantis fails to get off the ground Monday. In the meantime, all systems are go for Monday's launch try. The shuttle's communications system will be activated and checked out this afternoon and at 8:30 p.m., engineers plan to retract a protective servicing gantry from Atlantis, exposing the spacecraft to view and setting the stage for fueling early Monday. A 13-hour 22-minute "hold" in the countdown will end at 12:22 a.m. Monday when engineers will begin activating Atlantis's electricity producing fuel cells. The astronauts will be awakened at 3:15 a.m. for breakfast and a final weather briefing later in the morning. Assuming no problems develop, engineers will begin pumping a half-million gallons of liquid oxygen and liquid hydrogen rocket fuel into Atlantis's external tank shortly after 7 a.m. The three-hour fueling process should be complete by around 10 a.m. when NASA television coverage is scheduled to begin. At 11:17 p.m., the astronauts will participate in a routine photo op before donning their bright orange pressure suits and heading for pad 39A at 12:27 p.m. A final 40-minute hold at the T-minus nine-minute mark is scheduled to begin at 3:23 p.m. During this hold, engineers will update Atlantis's actual launch time based on the latest radar tracking of the international space station. The duration of the hold will be adjusted as required. =================================================================== Shuttle launch delayed by high crosswinds (04/24/00) 07:35 a.m. Update: Shuttle fueling underway; weather improves to 90 percent 'go' Engineers began pumping a half-million gallons of supercold liquid oxygen and liquid hydrogen rocket fuel aboard the shuttle Atlantis's external tank at 7 a.m. today, setting the stage for a launch attempt a few seconds before 4:15 p.m. There are no technical problems of any significance at pad 39A and forecasters now are predicting a 90 percent chance of acceptable weather during Atlantis's five-minute launch window. The shuttle's seven-member crew - commander James Halsell, pilot Scott Horowitz, flight engineer Jeffrey Williams, Mary Ellen Weber, Susan Helms, James Voss and Russian cosmonaut Yuri Usachev - were awakened at 3:15 a.m. for final preparations and briefings. The goal of the 98th shuttle mission is to repair the electrical system in a Russian propulsion module on the international space station that has been forced to operate longer than originally planned because of delays launching another Russian component called the service module. Halsell and company have three opportunities to get off the ground this week - today, Tuesday and Wednesday - or the flight will be delayed, possibly as late as May 11, because of conflicts with other rockets sharing Air Force Eastern Range tracking and telemetry equipment. If Atlantis launches today or Wednesday, the crew will dock with the international space station two days later during the crew's third day in space. A launch on Tuesday would require a flight-day-four rendezvous. Here is the schedule for the remainder of today's countdown: TIME.......EVENT 10:00 AM...NASA TV coverage begins 10:00 AM...Fueling complete 10:22 AM...Start a 2-hour built-in hold 11:17 AM...Crew lunch/photo opportunity 11:47 AM...Astronauts attend a final weather briefing 11:57 AM...The astronauts begin donning their pressure suits 12:22 PM...The countdown resumes 12:27 PM...The astronauts leave crew quarters and head for pad 39A 12:57 PM...The crew arrives at the launch pad to begin boarding 02:12 PM...The shuttle's hatch is closed 03:02 PM...Start a 10-minute hold 03:12 PM...The countdown resumes 03:17 PM...KSC area clear to launch 03:23 PM...Start a 40-minute built-in hold at the T-minus nine-minute mark. The exact launch time will be set during this hold based on final radar tracking of the space station; the most recent estimate was 4:14:56 p.m. 04:06 PM...The countdown resumes 04:15 PM...The launch window opens 04:20 PM...The launch window closes Atlantis's five-minute launch window is based on the shuttle's ability to reach the space station's orbit and then to rendezvous with the outpost. To do so, the shuttle must launch into the plane of the station's orbit. Earth's rotation will carry pad 39A into that orbital plane around 4:17:25 p.m. But the shuttle has enough power to launch five minutes to either side of that ideal launch time. In this case, however, NASA managers want to use propellant aboard Atlantis to boost the space station to a higher altitude. In so doing, they can preserve precious fuel aboard the station for future use. To save the required amount of propellant, a firing of Atlantis's orbital maneuvering system engines during launch will be shortened from one minute 42 seconds to just 59 seconds. That will save about 1,700 pounds of maneuvering fuel, enough to boost the station's altitude by 23 miles or so. But that 43-second shortfall in the so-called OMS-assist rocket firing during ascent translates into less power available to reach the space station's orbital plane. And so, the shuttle's launch window is just five minutes long. 10:40 a.m. Update: Shuttle fueling complete Engineers have completed loading the shuttle Atlantis's external tank with rocket fuel as they press ahead with today's countdown to launch. The only technical problem of any significance is the apparent failure of an electronic hardware interface module - HIM - "card" that controls the operation of the gaseous oxygen vent arm that positions a hood over the tip of the external tank until a few minutes before launch. A backup system is working normally. The concern is that a second failure could prevent the vent hood from pulling up away from the tank prior to the arm's motion away from the shuttle just before launch. As a result, a "red team" of technicians will be dispatched to the launch pad shortly to replace the suspect HIM card in Atlantis's mobile launch platform. The work is expected to take about an hour and no impact on launch is expected. 12:30 p.m. Update: Astronauts depart for launch pad Wearing bright-orange pressure suits, commander James Halsell and his six crewmates boarded a mobile home and headed for pad 39A today at just before 12:30 p.m. to strap in for launch on a space station repair mission. There are no technical problems of any significance and forecasters continue to predict generally good weather for a launch attempt at 4:15 p.m. But flight controllers are monitoring slightly high crosswinds at the shuttle's emergency runway where the crew would have to attempt a landing in the event of a main engine failure or some other problem during the first two minutes and 20 seconds of flight. NASA flight rules call for crosswinds no higher than 15 knots for daylight launches. As of this writing, actual crosswinds are right at the limit. While the rule can be waived by mission managers, that's not likely to happen if the crosswinds are more than a knot or so out of limits. Otherwise, there is little to report. Two minor problems with ground support equipment have been corrected and Atlantis appears ready to go, weather permitting. 02:00 p.m. Update: Launch time adjusted; high winds a concern Flight controllers have updated the shuttle Atlantis's launch time based on radar tracking of the international space station. Liftoff is now targeted for around 4:17:17 p.m., two minutes and 20 seconds or so later than earlier estimates. The latest launch time may be tweaked again by a few seconds during a final 40-minute hold at the T-minus nine-minute mark. Timelines posted below will be updated after liftoff based on the actual launch time. Forecasters, meanwhile, are continuing to monitor high winds at the Kennedy Space Center. Winds at the shuttle's emergency runway have been running between 15 and 22 knots with peak crosswinds of 18 knots. The crosswind limit for daylight launchings is 15 knots. If launch is delayed 24 hours, takeoff would be targeted for around 3:52:20 p.m. Tuesday. A Wednesday liftoff would be set for around 3:27 p.m. In all cases, the launch window will last just five minutes. The forecast for Tuesday calls for even higher winds with a chance of thunderstorms in the area while conditions are expected to improve Wednesday. If Atlantis is not off the ground by then, launch will be delayed to around May 11. Hoping for the best, Atlantis's crew has strapped in and technicians are in the process of sealing the shuttle's cockpit hatch in preparation for blastoff. There are no technical problems of any significance and weather remains the only issue. 03:25 p.m. Update: Shuttle countdown enters final hold The shuttle Atlantis's countdown entered a final planned hold at the T-minus nine-minute mark at 3:23 p.m. Liftoff on the 98th shuttle mission is targeted for around 4:17:17 p.m., although the actual time may change by a few seconds based on final radar tracking of the international space station. The launch window will close at 4:22:19 p.m. High crosswinds at the shuttle's emergency landing strip remain a major concern. As of this writing, forecasters are not optimistic the winds will change direction enough to lower the crosswind component to 15 knots or less, NASA's limit for daytime launches. Winds currently are steady at 13 knots with gusts above 19 knots. But this is Florida and this sort of micro forecasting is difficult to say the least. Will advise... 04:15 p.m. Update: Launch delayed at least 24 hours Launch of the shuttle Atlantis on a space station repair mission was delayed today at the T-minus nine-minute mark because of high winds at the shuttle's emergency landing strip. No decision has been made whether to attempt a launch Tuesday at 3:52:21 p.m. or whether to delay the flight to Wednesday at 3:27 p.m. The forecast for Tuesday calls for more high winds and a chance of thundershowers while the outlook Wednesday calls for favorable conditions. Engineers are tentatively gearing up for a Tuesday launch attempt, but no final decisions have been made. "Jim, it looks like the winds are going to be a little bit too high today for an RTLS and we'll need to call a scrub for today," launch director David King radioed commander James Halsell. "We will go ahead and attempt a 24-hour scrub-turnaround. We are going to talk weather for a few minutes to ... determine whether 24 or 48's better. But the right thing to do right now is to declare a 24 and we'll try again tomorrow." "OK. We understand the rationale and we sure appreciate everybody's hard work to try to get us off today," Halsell replied. "We'll wait until conditions are better. Thanks." Atlantis's seven-member crew strapped in on time today for a launch attempt at 4:17:17 p.m. Other than minor problems with ground support equipment, the countdown proceeded flawlessly to a final 40-minute hold at the T-minus nine-minute mark. But throughout the day, forecasters worried about high winds at the shuttle's emergency runway where Atlantis's crew would have to attempt a landing in the event of a main engine failure shortly after liftoff. NASA flight rules forbid a shuttle launch if crosswinds are higher than 15 knots. While that rule can be waived for slight variations, the wind was gusting at more than 20 knots at the runway during the final hold in the countdown. In the end, launch director David King, acting on recommendations from NASA's mission management team and flight director John Shannon, had no choice but to call off the countdown. A variety of factors will play in the decision on when to make another attempt. A launch Tuesday would force the crew to rendezvous with the international space station on flight day four, one day later than they would dock with a launch on Monday or Wednesday. NASA managers would like to extend Atlantis's mission by one day to give the crew more time to complete its repair and supply work. But that option would not be available if Atlantis launches Tuesday. On the other hand, flight plannerss do not like to give up launch dates based solely on weather. One of the primary goals of Atlantis's mission is to reboost the station's altitude using shuttle fuel. If the launch team gives up a Tuesday launch opportunity and then gets grounded Wednesday for some reason, the shuttle would be delayed to around May 11 because of conflicts with other rocket launches sharing the Air Force Eastern Range tracking system. In that case, station controllers would have to burn fuel aboard the Zarya module to boost the station's altitude. And no one wants to do that. 06:15 p.m. Update: Flight controllers refine mission timeline for possible April 25 launch NASA managers will meet at 5:45 a.m. Tuesday to decide whether to make another attempt to launch the shuttle Atlantis on Tuesday afternoon or to wait until Wednesday when better weather is expected. But flight planners, protecting against the possibility of a Tuesday launch are revising the crew's flight plan to reflect a flight-day-four rendezvous with the international space station. Even launch dates favor a docking on the third flight day but that option is not available Tuesday. In that case, docking would slip one day and mission managers would not be able to extend the mission a day, as had been hoped, to give the crew more time to complete its repair and resupply work. A detailed flight plan is not yet available. But here are the latest rendezvous numbers from the Johnson Space Center in Houston (times given in Eastern and mission elapsed time): DATE/TIME..DD...HH...MM...EVENT 04/25/00 03:52 PM...00...00...00...Launch 04:36 PM...00...00...44...OMS-2 orbit circularization rocket firing 07:35 PM...00...03...43...NC-1 rendezvous rocket firing 04/26/00 07:31 AM...00...15...39...NC-2 rendezvous rocket firing 02:58 PM...00...23...06...NC-3 rendezvous rocket firing 04/27/00 04:23 AM...01...12...31...NC-4 rendezvous rocket firing 02:49 PM...01...22...57...NC-5 rendezvous rocket firing 04/28/00 04:10 AM...02...12...18...NH rendezvous rocket firing 04:52 AM...02...13...00...NC-6 rendezvous rocket firing 06:23 AM...02...14...31...TI burn 09:47 AM...02...17...55...Atlantis docks with space station 04/29/00 07:27 AM...03...15...35...Spacewalk begins 01:57 PM...03...22...05...Spacewalk ends 04/30/00 05:07 AM...04...13...15...Space station ingress 05/01/0 04:22 AM...05...12...30...Reboost 1 start 05:21 AM...05...13...29...Reboost 1 stop 05/02/00 05:57 AM...06...14...05...Reboost 2 start 06:56 AM...06...15...04...Reboost 2 stop 05/03/00 05:22 AM...07...13...30...Reboost 3 start 05:50 AM...07...13...58...Reboost 3 stop 11:17 AM...07...19...25...Station egress 05/04/00 03:03 AM...08...11...11...Undocking 04:53 AM...08...13...01...Final separation 05/06/00 10:48 AM...10...18...56...Deorbit ignition 11:53 AM...10...20...01...Landing These numbers have been integrated into the STS-101 flight plan on the Current Mission page. The flight plan has been updated to include the additional rendezvous day. A final version will be posted Tuesday, along with an updated NASA television schedule, if mission managers decided to make another launch attempt Tuesday afternoon. =================================================================== High winds ground Atlantis a second straight day (04/25/00) 06:30 a.m., 04/25/00, Update: NASA managers decide to attempt Tuesday launch Despite predicted high winds, NASA managers met this morning and decided to make another attempt to launch the shuttle Atlantis at 3:52:21 p.m. today. Engineers plan to begin pumping liquid oxygen and liquid hydrogen rocket fuel into the shuttle's external tank around 7 a.m. Forecasters continue to predict high winds and a chance of thunderstorms during Atlantis's five-minute launch window, but NASA managers opted to press ahead anyway because of the pressing need to get Atlantis into orbit as soon as possible on a space station repair mission. If NASA gave up today's opportunity, the team would only have one more chance - Wednesday - to get the mission off before standing down to May 11 because of conflicts with other rocket launches sharing the Air Force Eastern Range tracking system. Here is a timeline of today's countdown activities: TIME.........EVENT 02:45 a.m....Crew wakeup 03:15 a.m....Astronauts have breakfast 05:00 a.m....A 2-hour built-in hold at the T-6 hour mark begins 07:00 a.m....Countdown resumes; fueling begins 09:30 a.m....NASA television coverage begins 10:00 a.m....Countdown enters a 2-hour hold at the T-3 hour mark 10:00 a.m....Fueling complete 10:47 a.m....Crew lunch photo op on NASA TV 11:17 a.m....The crew attends a final weather briefing 11:27 a.m....The astronauts suit up for launch 12:00 a.m....The countdown resumes at the T-3 hour mark 12:05 a.m....The astronauts depart crew quarters 12:35 a.m....The crew arrives at pad 39A 01:42 p.m....Atlantis's hatch is closed 02:40 p.m....A 10-minute hold at T-minus 20 minutes begins 02:50 p.m....The countdown resumes 03:01 p.m....The countdown enters a final planned hold at the T-minus nine-minute mark; the launch time is adjusted based on final tracking of the space station 03:43 p.m....The countdown resumes 03:52 p.m....Launch The STS-101 flight plan has been updated to reflect a launch this afternoon. A revised NASA television schedule also has been posted. This status report will be updated throughout the day. 08:00 a.m., 04/25/00, Update: Fueling proceeding smoothly With rain showers approaching, engineers began fueling the shuttle Atlantis around 6:30 a.m. today - about a half-hour ahead of schedule - for liftoff on a space station repair mission at 3:52 p.m. While the forecast is not particularly favorable, NASA managers are hoping storms and high winds associated with a frontal system will move through the launch area and leave calmer conditions in their wake by the time Atlantis's five-minute launch window opens. There are no technical problems of any significance. 09:30 a.m., 04/25/00, Update: Launch window adjusted slightly Flight controllers have updated the shuttle Atlantis's launch window based on radar tracking of the international space station. The five-minute window will open at 3:52:32 p.m. and close around 3:57:32 p.m. This window will be updated again between now and launch and may change by a few seconds either way. The launch window for Wednesday will open at 3:26:50 p.m. and close five minutes later. 10:30 a.m., 04/25/00, Update: Fueling complete The shuttle Atlantis's external tank has been topped off with a full half-million-gallon load of liquid oxygen and liquid hydrogen rocket fuel. There are no technical problems of any significance and the only issue remains the likelihood of high winds during the shuttle's five-minute launch window. "The final inspection team has just arrived on the 195-foot level of the fixed service structure and their only comment so far is it's very, very windy at the launch pad," said NASA launch commentator George Diller. The STS-101 flight plan has been updated with NASA's latest numbers. This is a "final" version and will not change between now and launch. 12:10 p.m., 04/25/00, Update: Astronauts suit up for launch The Atlantis astronauts attended a final weather briefing, suited up and headed for launch pad 39A today for blastoff at 3:52 p.m., weather permitting. Winds at the shuttle's emergency runway are forecast to be out of the west between 22 and 25 knots, higher than allowed by NASA safety rules. Shuttle managers are hoping the wind will change direction later in the day, reducing the crosswind component to 17 knots or lower. NASA safety rules forbid a launch if crosswinds are above 17 knots and even that takes a "go" recommendation from an astronaut flying approaches in a jet rigged to handle like a space shuttle. The normal daytime crosswind limit is 15 knots. "The astronauts have just completed the flight crew weather briefing," NASA launch commentator George Diller said around 11:45 a.m. "The thrust of the briefing, provided by the Space Flight Meteorology Group in Houston, was that as far as KSC is concerned, if we liked yesterday, we'll love today. There does not appear to be a whole lot of hope that we'll get a relief from the crosswind conditions." Hoping for the best, shuttle commander James Halsell and his six crewmates left their quarters and departed for pad 39A at 12:06 p.m. For today's launch, a main engine failure or some other major systems problem in the first two minutes 17 seconds of flight would leave the crew with no other choice but to attempt an emergency return to the launch site, a so-called RTLS abort. This is the riskiest intact shuttle abort mode, requiring the spacecraft to turn around at high velocity for an unpowered glide back to the Kennedy Space Center. For an engine failure between a mission elapsed time of two minutes 18 seconds and four minutes 32 seconds into flight, the crew would attempt an emergency landing in Spain or Africa, a more benign scenario than the RTLS because the shuttle would be able to continue in the same general direction. For an engine failure after four minutes 33 seconds, the shuttle could achieve a lower-than-planned orbit, the most benign abort mode of all. While the crew probably could not complete its space station docking mission in that case, the shuttle would be able to make a normal return to the United States. But in all shuttle landings, the orbiter makes its final approach to the runway as an unpowered glider. The shuttle currently is certified to handle crosswinds up to 17 knots if the launch weather pilot - for today's launch try, chief astronaut Charles Precourt - feels comfortable about it. While the spacecraft probably could handle even higher loads, flight director John Shannon made it clear Monday he would not go past the 17-knot limit. 01:40 p.m., 04/25/00, Update: Winds remain out of limits The shuttle Atlantis's launch time has been updated based on NASA's continuing analysis of the international space station's orbit. The new launch time is 3:53:17 p.m. and the window will extend a full five minutes. At this point, however, the issue appears moot; high winds continue to buffet the Kennedy Space Center and forecasters are not optimistic conditions will improve enough to permit a liftoff today. Off shore east of Jacksonville, where Atlantis's boosters would fall into the Atlantic Ocean after use, the crews of two booster recovery ships report seven- to nine-foot seas with winds of 30 to 35 knots. But there are no technical problems of any significance and the countdown is proceeding toward a final 40-minute hold at the T-minus nine-minute mark. The crew has strapped in, the shuttle's cockpit hatch has been closed and sealed and mission managers continue to monitor the weather in hopes the wind will change direction enough to reduce crosswinds at the shuttle's emergency runway. 02:25 p.m., 04/25/00, Update: Launch scrubbed by high winds; NASA will try again Wednesday For the second day in a row, launch of the shuttle Atlantis on a space station repair mission has been delayed by high winds at the shuttle's emergency runway. Today's launch attempt was scrubbed at 2:19 p.m. at the T-minus 41-minute mark in the countdown. NASA will make an unprecedented third straight attempt to launch Atlantis Wednesday at 3:27 p.m. If Atlantis is delayed again, launch will slip to around May 11 because of conflicts with other rockets awaiting launch on the Air Force Eastern Range. "It looks like the winds at the SLF [Shuttle Landing Facility] are pretty far out of limits and not going to come back in today," launch director David King radioed the crew. "So in light of that, we're going to call a scrub for the day. Also, in light of the range schedule, we're going to plan a 24-hour scrub turnaround and we'll try again tomorrow." "OK, copy that," commander James Halsell replied. "We knew our chances were iffy with the winds today but it was the right thing to do to try. We appreciate everybody's efforts and we'll be ready to support tomorrow." Forecasters expect a 90 percent chance of good weather during Atlantis's five-minute launch window Wednesday. In Florida, that is. At emergency runways in Spain and Africa, forecasters are predicting bad weather. At least one of those sites must be available for launch in case of an engine failure during ascent that would leave the shuttle without enough power to reach orbit or return to the Kennedy Space Center. Here is the countdown summary for Wednesday: 02:15 a.m....Crew wakeup 02:45 a.m....Astronauts have breakfast 04:34 a.m....Countdown enters a 2-hour hold at T-minus six hours; managers clear Atlantis for fueling 06:34 a.m....Countdown resumes; fueling begins 09:00 a.m....NASA television coverage begins 09:34 a.m....Countdown enters a two-hour hold at T-minus three hours; fueling complete 10:17 a.m....Astronaut photo/TV opportunity 10:47 a.m....Crew attends final weather briefing 10:57 a.m....Astronauts suit up for launch 11:34 a.m....Countdown resumes 11:44 a.m....Astronauts depart crew quarters 12:14 a.m....Astronauts arrive at pad 39A 01:12 p.m....Atlantis's hatch is closed 02:14 p.m....Countdown enters a 10-minute hold at T-minus 20 minutes 02:24 p.m....Countdown resumes 02:35 p.m....Countdown enters a final 40-minute hold at the T-minus nine-minute mark; the launch time is adjusted by about three minutes based on space station tracking updates 03:18 p.m....Countdown resumes 03:27 p.m....Launch Halsell and his six crewmates strapped in today at 12:30 p.m. for a launch attempt at 3:53 p.m. and the countdown proceeded flawlessly into its final hour. But throughout the day, forecasters worried about high winds at the shuttle's emergency runway where Atlantis's crew would have to attempt a landing in the event of a main engine failure shortly after liftoff. NASA flight rules forbid a shuttle launch if crosswinds are higher than 15 knots. The limit can be increased to 17 knots based on the recommendation of an astronaut flying runway approaches in a NASA jet rigged to handle like a space shuttle. But crosswinds remained too high and King had no choice but to call another delay. Wednesday's launch try will mark the first time in shuttle history that NASA will have made three back-to-back launch attempts. NASA normally makes two attempts and then stands down a day to give engineers a chance to rest and to restore propellant supplies. But crew rest is less of an issue for Atlantis's launch than most because liftoff is scheduled for the middle of the afternoon during a normal work shift. On top of that is a pressing need to get this mission off the ground as soon as possible to repair the international space station's electrical system and to boost the outpost to a higher altitude. Recent solar activity has caused Earth's atmosphere to swell slightly, increasing the resistance felt by the station as it moves through the extreme upper regions of the atmosphere. In recent weeks, the station has been falling about a mile and a half a week. The station's Russian-built Zarya module - the same one with the electrical problems - could reboost the station on its own, but that would use up precious on-board fuel. NASA wants to use the shuttle's fuel for reboost if at all possible to protect against the possibility of additional space station assembly delays down the road that might require use of Zarya's propulsion system. But time is running out. The station will reach a predefined altitude limit May 5 and if Atlantis is delayed Wednesday, flight controllers will have no choice but to reboost using on-board propellant. The flight plan and television schedules below will be updated as soon as possible. 03:30 p.m., 04/25/00, Update: Updating flight plan for Wednesday launch Here are the latest times for major mission events from the STS-101 flight plan, updated to reflect a launch Wednesday at 3:27 p.m. (the launch time will be updated Wednesday based on analysis of the international space station's orbit): DATE/TIME..DD...HH...MM...EVENT 04/26/00 03:27 PM...00...00...00...Launch 04/27/00 07:07 AM...00...15...40...NC-2 rendezvous rocket firing 04:01 PM...01...00...34...NC-3 rendezvous rocket firing 04/28/00 03:37 AM...01...12...10...Rendezvous operations begin 04:52 AM...01...13...25...NC-4 rendezvous rocket firing 06:24 AM...01...14...57...TI rendezvous rocket firing 09:48 AM...01...18...21...Space station docking 04/29/00 07:02 AM...02...15...35...Spacewalk begins 01:32 PM...02...22...05...Spacewalk ends 04/30/00 04:42 AM...03...13...15...Space station ingress 05/01/00 03:57 AM...04...12...30...Reboost 1 start 04:56 AM...04...13...29...Reboost 1 stop 05/02/00 05:32 AM...05...14...05...Reboost 2 start 06:31 AM...05...15...04...Reboost 2 stop 05/03/00 04:57 AM...06...13...30...Reboost 3 start 05:56 AM...06...14...29...Reboost 3 stop 10:52 AM...06...19...25...Station egress 05/04/00 03:06 AM...07...11...39...Space station undocking 05/06/00 10:59 AM...09...19...32...Deorbit ignition 12:03 PM...09...20...36...Landing The timing of some events may change slightly and a final version of the flight plan will be posted later this evening or early Wednesday. A revised NASA television schedule will be posted as soon as it is available. =================================================================== Shuttle Atlantis grounded a third time by weather (04/26/00) 07:30 a.m. Update: Atlantis refueled for third launch try Engineers are refueling the shuttle Atlantis for an unprecedented third day in a row in a bid to launch the orbiter on a space station repair mission after back-to-back weather delays Monday and Tuesday. With forecasters predicting a 90 percent chance of good weather at the Kennedy Space Center, Atlantis's liftoff on the 98th shuttle mission is targeted for 3:26:50 p.m. The launch window will close five minutes later. If Atlantis fails to get off the ground today, launch will be delayed to around May 11 because of conflicts with other upcoming rocket launches or tests that require use of Air Force Eastern Range radar and telemetry systems. The Eastern Range, which also controls self-destruct systems, is used by all rockets launched from the East Coast. Atlantis was ground Monday and Tuesday by high winds at a nearby emergency runway where the crew would have to attempt a landing in the event of a main engine failure in the first two minutes and 17 seconds of flight. Today's forecast calls for scattered clouds at 4,000 feet and northwest winds at 14 knots gusting to 20 knots at the launch pad. At the runway, the winds will be slightly less and the crosswind component should be within limits. The only question mark today appears to be the weather at three emergency landing sites in Spain and Africa where the shuttle would have to land if an engine failed between a mission elapsed time of two minutes 18 seconds and four minutes 32 seconds. After that, Atlantis could reach orbit on just two main engines. The latest forecast calls for low, multi-layer clouds at the three trans-Atlantic - TAL - landing sites: Zaragoza and Moron in Spain and Ben Guerir in Morocco. There's a chance of rain showers at both Spanish sites, but NASA managers are optimistic at least one of the landing strips will be acceptable during the two minutes and 14 seconds Atlantis is vulnerable to a trans-Atlantic abort. For the record, the last shuttle flight grounded by unacceptable TAL weather was mission STS-74 on Nov. 12, 1995. Here is the remainder of today's countdown: 09:00 a.m....NASA television coverage begins; fueling complete 09:34 a.m....Countdown enters a two-hour hold at T-minus three hours 10:17 a.m....Astronaut photo/TV opportunity 10:47 a.m....Crew attends final weather briefing 10:57 a.m....Astronauts suit up for launch 11:34 a.m....Countdown resumes 11:44 a.m....Astronauts depart crew quarters 12:14 a.m....Astronauts arrive at pad 39A 01:12 p.m....Atlantis's hatch is closed 02:14 p.m....Countdown enters a 10-minute hold at T-minus 20 minutes 02:24 p.m....Countdown resumes 02:35 p.m....Countdown enters a final 40-minute hold at the T-minus nine-minute mark; the launch time is adjusted by about three minutes based on space station tracking updates 03:18 p.m....Countdown resumes 03:27 p.m....Launch As mentioned above, this is the first time NASA has ever fueled a shuttle three days in a row. NASA managers usually permit two back-to-back launch attempts and then stand down a day to give the launch team a chance to rest. This time around, however, with Atlantis's launch window opening in the afternoon of a normal work day, program managers decided to make an exception in a bid to maximize the odds of getting the mission underway. An updated NASA television schedule (rev. B) has been posted below, along with a revised STS-101 flight plan based on the latest numbers from NASA. 09:45 a.m. Update: Forecast for landing sites in Spain, Africa, 'no go' The shuttle Atlantis has been loaded with a half-million gallons of liquid oxygen and liquid hydrogen rocket fuel for a launch attempt at 3:26:50 p.m. There are no technical problems of any significance at pad 39A and the weather at the Kennedy Space Center appears ideal after back-to-back delays Monday and Tuesday due to high winds. But forecasters say conditions at three emergency landing sites in Spain and Africa currently are observed "no go" and predicted to be no go at launch. Shuttle managers are hoping conditions at one of the sites will improve enough by launch time to permit a liftoff, but as of this writing they do not appear very optimistic. Observers are reporting lightning and a low deck of broken clouds at Moron and Zaragoza in Spain while low clouds and high crosswinds are forecast for Ben Guerir in Morocco, an old Strategic Air Command base now operated by the Moroccan government. Here's a bit of background: ZARAGOZA, Spain: The Zaragoza Air Base, used by the U.S. Air Force and Spanish military forces, was designated a TAL site in 1983. The base has two parallel runways, one 9,923 feet long and the other 12,109 feet long. The longer runway is preferred for shuttle landings. BEN GUERIR, Morocco: The 14,000 foot runway at Ben Guerir was modified by NASA to support shuttle landings. Running exactly north-south, the runway is equipped with special navigation aids and lighting equipment required by space shuttle crews. As a military base, the Ben Guerir complex is surrounded by fencing with guard towers spaced along the boundary. The nearest town of any size is Marrakech with a population of 265,000. MORON, Spain: Home of the 496th Air Base Squadron, Moron features an 11,840-foot runway. It has been five years since a shuttle has been grounded by bad weather at the trans-Atlantic abort sites. If Atlantis fails to get off the ground today, launch could be delayed to May 11. 11:45 a.m. Update: Astronauts head for pad The Atlantis astronauts, decked out in bright orange pressure suits, left crew quarters at 11:41 a.m. and headed for pad 39A to strap in for blastoff today at 3:26:50 p.m. There are no technical problems of any significance but forecasters are continuing to discuss potential weather problems at three emergency runways in Spain and Africa. At Zaragoza, Spain, showers are predicted within 20 nautical miles of the runway - a violation of NASA safety rules - and a chance of broken clouds at 4,000 feet. At Moron, Spain, the forecast calls for rain and thundershowers within 20 nautical miles and a chance of broken clouds at 3,000 feet. At Ben Guerir in Morocco, forecasters are predicting a chance of broken clouds at 3,000 feet, another potential violation of NASA safety rules. But that's a worst-case scenario and NASA managers are optimistic one of the sites will be available at launch time. "All three of the sites are somewhat marginal today," said NASA launch commentator George Diller. "It looks like Ben Guerir will probably be our best shot, followed by Zaragoza in Spain. There was an extensive strategy discussion with the astronauts overseas who will be flying approaches to those runways looking at the weather and how we will develop a plan for which of the three sites we will use." That discussion, Diller said, "could go right up almost to launch to select which of the three sites will be optimum. However, there is a belief that one of these three sites is probably going to be available. We'll kind of watch that as we go along. It's still rather early in the countdown to tell exactly what the launch weather is going to be." 01:30 p.m. Update: Shuttle hatch closed; launch time adjusted The Atlantis astronauts have strapped in, the shuttle's hatch has been closed and all systems are go for a launch attempt at 3:29:13 p.m. The launch window, which will close at 3:34:16 p.m., has been adjusted slightly based on continuing analysis of the international space station's orbit. Additional updates are possible. There are no technical problems at pad 39A and the weather remains near perfect. But conditions at three emergency landing sites in Spain and Africa continue to be a concern. As of 1:15 p.m., observers were reporting low clouds and rain showers within 20 nautical miles of runways in Zaragoza and Moron, Spain. If those conditions persist, neither site would be available for Atlantis today. A third trans-Atlantic landing site, at Ben Guerir, Morocco, is marginal at present. A deck of scattered clouds is getting thicker and winds are from the west at 16 knots with peaks at 20. The runway at Ben Guerir runs due north and south, so these winds represent a stiff crosswind. NASA safety rules prohibit landings in crosswinds higher than 15 knots unless an astronaut flying approaches finds conditions acceptable. In that case, the crosswind limit can be raised to 17 knots. Rookie astronaut Paul Lockhart is on duty at Ben Guerir today. There's no way to predict how this will turn out. The decision on whether to proceed likely will not be made until the last minute. 02:35 p.m. Update: Countdown enters final planned hold at T-minus nine minutes The shuttle Atlantis's countdown entered a final planned hold at the T-minus nine-minute mark at 2:35 p.m. There are no technical problems of any significance and launch remains targeted for 3:29:13 p.m. While the weather in Florida appears ideal, flight controllers are still assessing conditions at three emergency runways in Spain and Africa. That is where Atlantis's crew would have to attempt a landing in the event of a main engine failure between two minutes 18 seconds into flight and four minutes 32 seconds. At this time, Zaragoza and Moron, Spain, are no-go due to low clouds and rain. A landing site at Ben Guerir, Morocco, is marginal due to high crosswinds and low clouds. NASA managers are hoping Ben Guerir or Zaragoza will improve enough by the opening of Atlantis's launch window to permit a liftoff today. This status report will be updated after the shuttle takes off or the flight is scrubbed. 03:25 p.m. Update: Shuttle launch scrubbed due to high winds in Africa For the third day in a row, the hard-luck shuttle Atlantis was grounded by bad weather, this time because of high winds and low clouds at emergency landing strips in Spain and Africa. It is not yet known when another attempt can be made to launch the shuttle on a space station repair mission. But the flight will slip to at least May 3 - and possibly as late as May 11 - because of conflicts with other upcoming rocket launches that share Air Force tracking systems. "Looks like everybody was trying to work to get us there today but we were just a little bit out," launch director David King radioed shuttle commander James Halsell. "So we're going to need to scrub for the day." "CDR copies," Halsell replied. Today's launch scrub was a frustrating disappointment to Halsell and company and to flight controllers operating the international space station. A Russian module on the station - Zarya - has suffered battery problems in recent weeks and needs repairs to its electrical system. In addition, recent solar activity has affected Earth's extreme upper atmosphere, causing the station to lose about a mile and a half of altitude each week. NASA wants to use spare fuel aboard the space shuttle to reboost the station's altitude, thus preserving the lab's limited on-board supplies. If Atlantis takes off by May 3 or shortly thereafter, flight controllers will not have to burn any of the station's fuel. But an Atlas rocket carrying NASA's next GOES weather satellite is scheduled for launch May 3 and it's not clear whether the space agency will bump this high-priority satellite. If Atlantis is delayed to May 11 - the next open date on the Air Force Eastern Range - flight controllers will have no choice but to fire the station's thrusters to increase altitude and to permit a flight day three or four rendezvous by the shuttle. Atlantis's seven-member crew strapped in today around noon for a launch attempt at 3:29 p.m. The countdown proceeded flawlessly to a final 40-minute hold at the T-minus nine-minute mark. But throughout the day, forecasters worried about high winds at emergency runways in Spain and Africa. Atlantis was grounded Monday and Tuesday by high winds at the Kennedy Space Center's shuttle runway. A main engine failure in the first two minutes 17 seconds of flight would force a crew to attempt an emergency return to the launch site. Because the shuttle makes an unpowered, gliding touchdown, good weather is required. Conditions in Florida today were ideal, but low clouds, rain and thunderstorms within 20 nautical miles made runways in Zaragoza and Moron, Spain, unusable while low clouds and high crosswinds - 16 knots with a night-time limit of just 12 - ruled out a Moroccan landing strip called Ben Guerir. Today's launch try marked the first time in shuttle history that NASA made three back-to-back launch attempts. NASA normally makes two attempts and then stands down a day to give engineers a chance to rest and to restore propellant supplies. But crew rest was less of an issue for Atlantis's launch than most because liftoff was scheduled for the middle of the afternoon during a normal work shift. 05:30 p.m. Update: NASA mulls possible May 3 launch date Shuttle managers are assessing the possibility of making a fourth attempt to launch the shuttle Atlantis on a space station repair mission as early as May 3. But that would require the National Oceanic and Atmospheric Administration to delay launch of a new GOES hurricane tracking satellite - currently scheduled for liftoff aboard an Atlas rocket May 3 - to around May 18. As of this writing, that's the next available launch date on the Air Force Eastern Range, the organization that provides radar tracking and telemetry support for all rockets launched from Florida. "There are a lot of options out there on the range," said launch director David King. "The range is very packed. [But] as everybody knows, the range schedule is dynamic. So we'll be evaluating all our options over the next day or two and I would think we could probably settle in on a date by the end of the week or early next week." Earlier in the day, May 11 was still an open slot on the range. But this afternoon, a Boeing Delta 2 rocket carrying an Air Force Global Positioning System satellite was granted launch opportunities on May 11 and 12. It takes one to two days to reconfigure the range to support a different launch vehicle and each range customer typically gets two launch opportunities before going to the back of the line. Here's the schedule as of this afternoon: DATE........ROCKET.......PAYLOAD 05/03-04....Atlas........GOES weather satellite 05/08-09....Titan 4B.....Air Force DSP missile warning satellite 05/11-12....Delta 2......Global Positioning System satellite 05/15-16....Atlas 3A.....Eutelsat communications satellite 05/18-19....TBD..........TBD The international space station, meanwhile, continues to lose altitude - about 1.5 miles per week - while awaiting the arrival of Atlantis. NASA had hoped to reboost the station using Atlantis's maneuvering jets, allowing flight controllers to conserve the station's limited on-board fuel supplies. But with Atlantis stuck on the ground, U.S. and Russian flight controllers are discussing the possibility of a rocket firing as early as Saturday to adjust the station's orbit slightly. While the "burn" would raise the station's altitude by some small amount, the primary purpose of the maneuver would be to preserve the capability for a shuttle docking later in the month on the flight's third or fourth day. This burn is not required for a possible May 3 launch of Atlantis. Through mid May, flight controllers say, a shuttle launch on odd dates results in a flight day four docking while a launch on even dates allows a docking on the third day of the mission. The proposed station rocket firing would enable similar docking scenarios later in the month. 05:45 p.m. Update: Flight plan update The STS-101 flight plan below has been updated to reflect a possible May 3 launch and a flight-day-four rendezvous with the international space station [see the next entry for details]. The launch time used for this schedule - 12:55 p.m. - assumes liftoff moves up 22 minutes per day between now and then. This may be an incorrect assumption. The actual launch time is not yet known and readers should use the schedule only for rough guidance on when major events will take place. The flight plan will be updated when a more accurate launch time is known. =================================================================== Shuttle Atlantis reset for May 18 launch try (04/28/00) The hard-luck shuttle Atlantis, grounded three days in a row by bad weather, has been rescheduled for launch on a space station repair mission May 18, after four already scheduled military and civilian rocket launches. U.S. and Russian flight planners are assessing ways to minimize use of the space station's limited on-board fuel for reboost operations until the shuttle arrives. While that assessment continues, no "burns" will be carried out before the middle of next week at the earliest. Shuttle planners say the delay will have no impact on plans to launch a critical Russian command module in July. But because Atlantis is scheduled to make the next visit to the station after the new module is launched, the current delay will force that flight to slip from mid August to Sept. 8. The next flight after that, shuttle mission STS-92, will move from Sept. 21 to October 8 while arrival of the station's first full-time crew likely will slip from Oct. 20 to at least mid November. Atlantis was grounded April 24, 25 and 26 by high winds at emergency runways in Florida and Africa. Shuttle managers lobbied hard for a fourth launch try on May 3, but that would have required delaying NOAA's new GOES weather satellite, scheduled for launch that day atop a Lockheed Martin Atlas rocket. While the new satellite is a spare, the GOES spacecraft currently monitoring the U.S. East Coast has had problems in recent weeks. Because of the possibility of a failure during hurricane season, the National Oceanic and Atmospheric Administration wants to get the new satellite into orbit as soon as possible. Had the shuttle taken the GOES slot, the weather satellite would have slipped to at least May 18 and possibly longer because of processing issues involving the GOES rocket and an Atlas 3 rocket on an adjacent pad that is scheduled for launch May 15. In the end, Joseph Rothenberg, NASA's associate administrator for space flight, decided to keep GOES where it is and to delay the shuttle to May 18 because of the possible threat to human life during hurricane season. Why May 18? All rockets launched from the East Coast of Florida share radar tracking, photo documentation and self destruct systems provided by the Air Force Eastern Range. It takes one to two days to reconfigure the range to support another launch vehicle and each range customer gets at least two launch opportunities. Here is the current schedule: DATE........ROCKET.......PAYLOAD 05/03-04....Atlas........GOES weather satellite 05/08-09....Titan 4B.....Air Force DSP missile warning satellite 05/11-12....Delta 2......Global Positioning System satellite 05/15-16....Atlas 3A.....Eutelsat communications satellite 05/18-19....Atlantis.....Shuttle/space station repair mission While precise timelines are not yet available, Atlantis's launch window will open around 6:33 a.m. on May 18. As of this writing - assuming no rocket firings are carried out by the space station - docking would occur on flight day four, around 12:30 a.m. on May 21. A spacewalk by James Voss and Jeffrey Williams would be carried out late that "night," beginning around 10 p.m. The crew then would enter the station around 8 p.m. on May 22, undock around 5:45 a.m. on May 26 and land back at the Kennedy Space Center around 2:30 a.m. on May 29. Again, these are strictly "ballpark" figures; the flight plan will change based on the space station's actual orbit and other factors. Given the uncertainty about how the station's orbit might ultimately be adjusted, two versions of the STS-101 flight plan have been posted below, one for a flight-day-three rendezvous and one for FD-4. The international space station, meanwhile, continues to fall about a mile-and-a-half per week. Recent solar activity has caused Earth's atmosphere to swell slightly, increasing the friction, or drag, the station experiences as it flies through the extreme upper atmosphere at five miles per second. The effect is directly proportional to the size of the spacecraft and inversely proportional to altitude, i.e., the lower the spacecraft, the higher the drag and the faster the satellite falls. All spacecraft in low-Earth orbit experience this braking force and require periodic reboosting. NASA had hoped to use spare propellant aboard the Atlantis to reboost the station by about 23 miles without having to tap into the lab's limited on-board fuel supplies. But with the shuttle's launch now targeted for May 18, that may not be possible. As it now stands, no rocket firings are planned before next week. Flight planners say Atlantis probably can reach the station for a flight-day-four rendezvous without having to use up any on-board fuel. But a flight-day-three rendezvous likely would be unavailable without an orbit adjust burn of some sort. Flight planners are studying the possibility of changing the way the shuttle's rendezvous rocket firings are carried out to minimize any use of station propellant. The reluctance to use Zarya's on-board fuel for orbital adjustment stems from a general desire to conserve any on-orbit consumables - fuel, water, etc. - to provide margin for handling unforseen problems down the road. In this case, Zarya has enough fuel to adjust the station's orbit and to carry out two docking attempts with the Russian service module, a key command and control module scheduled for launch in July. =================================================================== NASA managers refine launch options (05/04/00) U.S. and Russian flight controllers continue to assess a variety of options for when to launch the shuttle Atlantis on a space station repair mission. Atlantis was delayed three days in a row - April 24, 25 and 26 - by high winds at emergency runways in Florida, Spain and Africa. After a detailed review, NASA managers today agreed to stick with a previously announced May 18 target for Atlantis's fourth launch try. But as with everything else in this mission, the picture is more complicated than it might first appear. The primary goals of the 98th shuttle mission is to replace degraded batteries aboard the station's Russia Zarya module, to repair communications gear and to install fans and other equipment to improve air circulation. Station managers also want to use fuel aboard Atlantis to reboost the station's altitude. Because of recent solar activity, the lab has been losing altitude faster in recent weeks than might otherwise be expected. As of May 18, the station's orbit will measure 181 by 176 nautical miles. By May 30, if left alone, the lab's orbit will measure about 177 by 173 nautical miles for an average drop of roughly two nautical miles per week. While the Zarya module is equipped with a propulsion system, managers want to conserve its limited on-board fuel as much as possible to protect against problems down the road. In the wake of Atlantis's launch delays, flight planners initially thought they would have to fire Zarya's thrusters to both reboost the station's altitude and to put it in a position to permit Atlantis to have flight-day-three and flight-day-four docking opportunities through the end of the month. U.S. and Russian space station managers discussed the issue Wednesday and decided not to order any such firing quite yet, reserving May 15 for a possible rocket boost if flight planners ultimately determine one is necessary. Assuming no orbital adjustment burns are ordered, here are the latest launch window estimates for Atlantis's fourth launch try and estimates for when the shuttle would dock with the international space station (all times/estimates in Eastern): DATE.......WINDOW OPEN.....WINDOW CLOSE....RENDEZVOUS DAY 05/18/00...06:33:16 a.m....06:43:16 a.m....Flight Day 4* 05/21/00...................................12:22 a.m. docking 05/19/00...06:07:33 a.m....06:17:33 a.m....FD-3 05/21/00...................................12:22 a.m. docking 05/20/00...05:44:59 a.m....05:54:59 a.m....FD-4* 05/23/00...................................Late night docking 05/21/00...05:19:16 a.m....05:29:15 a.m....FD-3* 05/23/00...................................Late night docking 05/22/00...No favorable rendezvous scenarios 05/23/00...04:30:58 a.m....04:40:58 a.m....FD-3 05/25/00...................................Late night docking 05/24/00...No favorable rendezvous scenarios *Launch on these dates would require a "retrograde" rendezvous rocket firing by the shuttle shortly after launch (NC-1 burn) to make a rendezvous possible. Atlantis would still have enough propellant to reboost the station by 20 miles or so. To catch up with the space station, Atlantis must launch within a few minutes of the time its launch pad rotates into the plane of the station's orbit. For a liftoff on May 18, this "planar" window will open at 6:33:16 a.m. and close 10 minutes later. For the first three launch tries, Atlantis was limited to a five-minute "performance" window based on a desire to save 1,700 pounds of fuel for use boosting the station's orbit. As of this writing, details about a performance window for May 18 are not yet known. As such, readers should keep in mind the 10-minute launch windows listed below are "best case" and may be shortened depending on rendezvous requirements. NASA managers would prefer a flight-day-three rendezvous if at all possible. A flight-day-three mission could be extended one day if necessary for additional station work while an FD-4 mission could not. As such, mission managers debated giving up May 18 and shooting for a launch on May 19 instead. That would provide two flight-day-three opportunities in three days. But today, agency managers decided to stick with the original May 18 target. On another front, shuttle managers have decided not to attempt three back-to-back launch attempts this time around. They did so for Atlantis' first three launch tries, but the effort exhausted the launch team. Managers with NASA and prime contractor United Space Alliance have agreed to go back to the old way of doing business, that is, to make two attempts in a row if necessary and then to stand down a day to give the launch time a chance to rest. =================================================================== Launch window refined; countdown options explained (05/05/00) Flight planners at the Johnson Space Center in Houston are continuing to refine the shuttle Atlantis's launch window for a May 18 flight to the international space station. Atlantis must launch within about five minutes to either side of the moment when its launch pad rotates into the plane of the station's orbit. This "planar" window will open at 6:33:15 a.m. on May 18 and close 10 minutes later. But the preferred launch window, i.e., the period within the overall planar window that maximizes fuel conservation and performance, will open at 6:37:57, 20 seconds or so before the precise instant the launch pad is directly in the plane of the station's orbit. The preferred launch window will last five minutes. These times likely will change slightly between now and launch based on updated radar tracking of the space station. Atlantis's seven-member crew - commander James Halsell, pilot Scott Horowitz, flight engineer Jeffrey Williams, Mary Ellen Weber, Susan Helms, James Voss and Russian cosmopnaut Yuri Usachev - plans to fly back to the Kennedy Space Center the night of May 14, arriving around 9 p.m. The countdown for Atlantis's fourth launch try will begin at 9 a.m. on May 15. Assuming Atlantis takes off on schedule, here's an updated timeline of major mission events (these numbers have been incorporated in the detailed STS-101 flight plan posted below): TIME/DATE..DD...HH...MM...EVENT 05/18 06:38 AM...00...00...00...Launch; at this moment, the space station is over the southern Pacific Ocean due south of Tahiti (39.9 degrees south latitude, 146.5 degrees west longitude) 05/20 09:43 PM...02...15...05...Final rendezvous begins (TI burn) 05/21 12:29 AM...02...17...51...Atlantis docks with the space station 10:13 PM...03...15...35...Spacewalk begins 05/22 04:43 AM...03...22...05...Spacewalk ends 07:53 PM...04...13...15...Astronauts enter space station 05/26 07:02 PM...08...12...24...Undocking 08:52 PM...08...14...14...Final separation 05/29 01:11 AM...10...18...33...Deorbit ignition 02:14 AM...10...19...36...Landing Atlantis's countdown is complicated by the planned launch of a Lockheed Martin Atlas 3R rocket from the nearby Cape Canaveral Air Force Station at 5:37 p.m. on May 15. All rockets launched from the East Coast of the United States share radar tracking and self destruct services provided by the Air Force Eastern Range. The Range can support just one rocket at a time. Each vehicle gets at least two back-to-back launch opportunities and it takes the Range a day or longer to reconfigure equipment to support another vehicle. For the Atlas 3R's maiden voyage, the Range is providing three back-to-back launch opportunities on May 15, 16 and 17. If the new rocket takes off on schedule, it will have no impact on Atlantis's launch. If the Atlas fails to get off on May 15, tries again and fails on May 16, shuttle engineers will insert a 24-hour hold at the T-minus 11-hour mark in Atlantis's countdown and delay launch one day. If the Atlas fails to get off on May 15 and a 48-hour recycle is ordered, shuttle engineers will delay loading reactants for the shuttle's electrical generators and insert a 24-hour hold at the T-minus 27-hour mark. Again, launch would be delayed one day. =================================================================== Rendezvous timeline refined (05/09/00) Flight controllers continue to refine the shuttle Atlantis's rendezvous timeline for docking with the international space station. For readers interested in such detail, here are the latest numbers (in Eastern and mission elasped time): DATE/TIME..DD...HH...MM...EVENT 05/18/00 06:38 AM...00...00...00...Launch 10:20 AM...00...03...42...NC-1 rendezvous rocket firing 10:16 PM...00...15...38...NC-2 rendezvous rocket firing 05/19 07:12 AM...01...00...34...NC-3 rendezvous rocket firing 10:06 PM...01...15...28...NC-4 rendezvous rocket firing 05/20 05:33 AM...01...22...55...NC-5 rendezvous rocket firing 07:02 PM...02...12...24...NH rendezvous rocket firing 08:06 PM...02...13...28...NC-6 rendezvous rocket firing 09:43 PM...02...15...05...Terminal Initiation phase rocket firing 05/21/00 12:29 AM...02...17...51...Atlantis docks with space station 05/26 07:02 PM...08...12...24...Atlantis undocks from space station 08:52 PM...08...14...14...Final separation rocket firing 05/29 01:11 AM...10...18...33...Deorbit ignition 02:14 AM...10...19...36...Landing at the Kennedy Space Center An updated countdown timeline has been posted below, along with a new version of the STS-101 flight plan that reflects the above rendezvous times. =================================================================== Atlantis launch windows updated; no station rocket firings planned (05/09/00) NASA flight controllers have updated the shuttle Atlantis's launch windows for May 18 through May 21. To maximize performance and to conserve propellant, NASA will target launch for the opening of a so-called "preferred" launch window. This window will last five minutes. Here are the latest numbers: DATE....PLANAR OPEN...PREFERRED OPEN...PREFERRED CLOSE..DOCKING DAY 05/18...06:33:18 AM...06:38:18 AM......06:43:18 AM......Flight Day 4* 05/19...06:07:35 AM...06:12:35 AM......06:17:35 AM......FD-3 05/20...05:45:02 AM...05:50:02 AM......05:55:02 AM......FD-4* 05/21...05:19:19 AM...05:24:19 AM......05:29:19 AM......FD-3* In the meantime, NASA and Russian space station controllers have decided not to fire the Russian Zarya module's maneuvering jets to raise the station's orbit prior to Atlantis's arrival. For the moment, at least. While the station continues to lose altitude due to atmospheric friction, or drag, controllers say Atlantis will be able to reach the outpost and reboost it without first using Zarya's limited on-board fuel supplies. The statin's orbit will be re-evaluated next week and a rocket firing could still be carried out on May 16 if necessary. See the latest NASA status report below for additional details. =================================================================== Launch window, timeline changes. Again. (05/11/00) In what is becoming an almost daily ritual, NASA flight planners have updated the shuttle Atlantis's launch window and flight plan based on the latest radar tracking data about the orbit of the international space station. Just hours after an updated launch window chart was posted here Wednesday [see next entry], a new launch window was generated by NASA, along with changes to the mission timeline. NASA now says the STS-101 preferred launch window will open at 6:37:58 a.m. on May 18 and close at 6:43:18 a.m. This is 20 seconds earlier than reported Wednesday. Docking with the international space station now is expected to occur at 12:32 a.m. on May 21 - just a few minutes later than shown on the most recent previous schedule - but undocking will move up an hour and a half, from 7:02 p.m. on May 26 to 5:32 p.m. For those of you attempting to score this one at home - and it's not easy! - here are the latest timeline numbers: DATE/TIME..DD...HH...MM...EVENT 05/18/00 06:38 AM...00...00...00...Launch 10:20 AM...00...03...42...NC-1 rendezvous rocket firing 10:16 PM...00...15...38...NC-2 rendezvous rocket firing 05/19 07:13 AM...01...00...35...NC-3 rendezvous rocket firing 10:07 PM...01...15...29...NC-4 rendezvous rocket firing 05/20 05:35 AM...01...22...57...NC-5 rendezvous rocket firing 07:04 PM...02...12...26...NH rendezvous rocket firing 08:09 PM...02...13...31...NC-6 rendezvous rocket firing 09:40 PM...02...15...02...Terminal Initiation phase rocket firing 05/21/00 12:32 AM...02...17...54...Atlantis docks with space station 05/26 05:32 PM...08...10...54...Atlantis undocks from space station 07:22 PM...08...12...44...Final separation 05/29 01:14 AM...10...18...36...Deorbit ignition 02:18 AM...10...19...40...Landing These numbers have been plugged into the STS-101 flight plan posted below. But NASA has not yet provided a detailed flight plan update reflecting changes that will be necessary because the shuttle's undocking from the space station has moved up by one orbit. This likely will affect sleep shifts and other events toward the end of the mission. An update will be posted as soon as a new flight plan is generated. In addition, the countdown timeline below has been updated to reflect the proper start and stop times for various holds and other events. The countdown posted earlier was off by one minute because the original timeline provided by NASA targeted the wrong window opening. Finally, an updated version of SpaceCalc will be posted here as soon as a reliable flight plan can be included. =================================================================== NASA revises mission flight plan (05/13/00) In what this author sincerely hopes will be the final major update before launch, NASA has revised the STS-101 flight plan yet again, this time to reflect changes in crew sleep shifting that, in turn, necessitated numerous other changes. The flight plan is posted below, along with the initial release of NASA's television schedule for coverage of mission events. In addition, updated launch windows through May 25 have been posted below. =================================================================== Countdown begins for fourth launch try (05/15/00) Grounded three days in a row last month by high winds, the shuttle Atlantis is poised for a fourth launch try Thursday to kick off a long-awaited space station repair mission. The countown to blastoff began at 9:30 a.m. today and if all goes well, Atlantis will finally thunder away at 6:37:58 a.m. Thursday, the opening of a five-minute launch window. There are no technical problems at pad 39A and forecasters are predicting a 90 percent chance of good weather Thursday, Friday and Saturday in Florida. And forecasters with the Spaceflight Meteorology Group at the Johnson Space Center in Houston say good conditions also are expected at the shuttle's emergency runways in Spain and Africa. Atlantis was grounded April 24 and 25 by high winds in Florida and again on April 26 by high winds and rain at the overseas landing sites. "Here we are again, ready to pick up the launch count," NASA test director Steve Altemus said earlier today. "The vehicle is in great shape." Here is the latest schedule of major mission events (a detailed flight plan is posted below, along with NASA's television schedule): DATE/TIME..DD...HH...MM...EVENT 05/18/00 06:38 AM...00...00...00...Launch 10:20 AM...00...03...42...NC-1 rendezvous rocket firing 10:16 PM...00...15...38...NC-2 rendezvous rocket firing 05/19 07:13 AM...01...00...35...NC-3 rendezvous rocket firing 10:07 PM...01...15...29...NC-4 rendezvous rocket firing 05/20 05:35 AM...01...22...57...NC-5 rendezvous rocket firing 07:04 PM...02...12...26...NH rendezvous rocket firing 08:09 PM...02...13...31...NC-6 rendezvous rocket firing 09:40 PM...02...15...02...Terminal Initiation phase rocket firing 05/21/00 12:32 AM...02...17...54...Atlantis docks with space station 11:18 PM...03...16...40...Spacewalk begins 05/22 05:43 AM...03...23...05...Spacewalk ends 08:38 PM...04...14...00...Astronauts enter space station 05/26 03:03 AM...07...20...25...Astronauts exit space station 05:32 PM...08...10...54...Atlantis undocks from the space station 07:22 PM...08...12...44...Final separation 05/29 01:14 AM...10...18...36...Deorbit ignition 02:18 AM...10...19...40...Landing NASA's launch strategy calls for making two tries in a row Thursday and Friday, if necessary, and then to stand down a day to give the launch team a chance to rest. Another attempt could be made on May 21, but the 22nd is not available because it would require an excessive amount of fuel to rendezvous with the space station. A fifth launch attempt could be staged May 23 if worse came to worse. At the nearby Cape Canaveral Air Force Station, Lockheed Martin engineers are gearing up to launch a new Atlas 3 rocket on its maiden flight this evening at 5:37 p.m. The launch window will close at 7:57 p.m. The Atlas 3 is the first U.S. rocket to be equipped with a Russian first-stage engine. Because this is the Atlas 3's maiden voyage, the Air Force Eastern Range, which provides radar tracking and telemetry support for all rockets launched from the East Coast, has given Lockheed Martin three back-to-back launch opportunities. If the Atlas 3 fails to get off the ground today or Tuesday, forcing the company to make a third attempt Wednesday, Atlantis's launch will slip 24 hours to May 19 at 6:12:35 a.m. A detailed mission preview is available in the Reporter's Notebook at the bottom of this page, along with a sidebar on Atlantis's new "glass cockpit." A NOTE ABOUT LAUNCH WINDOWS To rendezvous with the international space station, Atlantis must take off within five minutes of the time when Earth's rotation carries the launch pad into the plane of the station's orbit. This normally would give NASA 10 minutes to get the shuttle off the ground. But for Atlantis's flight, mission managers want to conserve propellant to reboost the station's altitude by 20 miles or so. This requirement, coupled with the demands of reaching the station's orbit in the first place, have shortened Atlantis's launch window to just five minutes. This "preferred" window will open 20 seconds before the instant when the pad rotates into the plane of the station's orbit. =================================================================== Shuttle crew awaits Atlas launch outcome (05/16/00) The shuttle Atlantis's countdown continues to tick smoothly toward blastoff Thursday on a thrice-delayed space station repair mission. There are no technical problems at pad 39A and forecasters continue to predict a 90 percent chance of good weather during Atlantis's five-minute launch window Thursday. The window will open at 6:38 a.m. and close at 6:43 a.m. But that assumes a Lockheed Martin Atlas 3 rocket making its maiden flight gets off the ground later today from the nearby Cape Canaveral Air Force Station. The new Atlas 3, a commercial rocket equipped with a Russian RD-180 first stage engine, was grounded Monday by a malfunctioning tracking radar in Bermuda. Engineers raced the clock late today to repair the tracking system in time for a launch attempt at 5:37 p.m. The launch window closes at 7:57 p.m. The launching will be carried live on Telstar 6, transponder 1, C-band, starting at 4:30 p.m. A live webcast of the flight will be provided by spaceflightnow.com. If the Atlas is delayed another 24 hours to Wednesday, Atlantis's launch will slip from 6:37:58 a.m. Thursday to 6:12:35 a.m. Friday. Again, good weather is expected both days. The NASA television schedule, the STS-101 mission flight plan, the countdown timeline and other mission-specific data below assume an on-time blastoff Thursday. Should launch be delayed, a 13-hour 13-minute hold in the countdown, scheduled to begin at 1:30 a.m. Wednesday, will be extended to around 36 hours 50 minutes. Under that scenario, the countdown would resume at 2:20 p.m. Thursday at the T-minus 11-hour mark. External tank fueling preparation would begin shortly thereafter. If launch is delayed, updated timelines will be posted here as soon as possible. This status report will be updated as soon as the Atlas takes off or as conditions warrant. =================================================================== Atlas launch delayed; shuttle slips to Friday (05/17/00) Launch of the shuttle Atlantis on a space station repair mission is expected to slip from Thursday to Friday, at 6:12:35 a.m., following the second straight weather delay for the maiden launch of a Lockheed Martin Atlas 3A rocket from the nearby Cape Canaveral Air Force Station. Buffeted by high winds and storm cells, the Atlas team gave up shortly before 5 p.m. and began recycling for a third launch attempt at 5:37 p.m. Wednesday - the team's final opportunity this week - which would push Atlantis's liftoff from Thursday to Friday. The space shuttle, commercial rockets and military launch vehicles all share Air Force Eastern Range radar tracking and telemetry equipment. It typically takes one to two days to reconfigure the Range to support a different launch vehicle and each Range customer gets at least two back-to-back launch opportunities. The Atlas 3A, making its first flight, was given three consecutive launch slots. A revised flight plan for Atlantis's mission, an updated television schedule and a revised countdown timeline will be posted below later this evening. This status report will be updated as warranted. =================================================================== Shuttle countdown holds for Atlas launch (05/17/00) NASA's shuttle launch team is standing by today awaiting liftoff of a Lockheed Martin Atlas 3A rocket from pad 36B at the nearby Cape Canaveral Air Force Station. The commercially developed rocket, the first major U.S. launcher equipped with a Russian main engine, is scheduled for liftoff at 5:37 p.m. The launch window will close at 7:57 p.m. Lockheed Martin tried to launch the Atlas 3A on Monday and then again on Tuesday, but high winds and storm cells blocked both attempts. While rockets using Air Force Eastern Range tracking equipment typically get just two back-to-back launch opportunities, the Atlas 3A was given three tries because it is a new rocket making its first flight. It takes one to two days to reconfigure Range tracking systems to support another flight. And so, when the Atlas launch slipped from Tuesday to Wednesday, NASA was forced to delay launch of the shuttle Atlantis on a space station repair mission from Thursday to Friday. There are no technical problems of any significance at pad 39A and forecasters continue to predict good weather for Friday's launching. Even so, the astronauts still could face problems. The Spaceflight Meteorology Group at the Johnson Space Center predicts marginal conditions at emergency runways in Spain and Africa where the crew would have to attempt a landing in the event of a main engine failure between two minutes 18 seconds into flight and four minutes 32 seconds. After that, the shuttle could limp into a lower-than-planned orbit with just two main engines. Atlantis was grounded April 24 and 25 by high winds at the Kennedy Space Center's shuttle runway and again on April 26 by bad weather at the overseas landing strips. Mission planners are keeping their fingers crossed conditions in Spain or Africa will improve between now and Friday. Atlantis's launch time has been updated slightly to reflect the latest data on the space station's actual orbit. The shuttle's five-minute 20-second launch window now is expected to open around 6:12:15 a.m. and close at 6:17:35 p.m. The space station rendezvous timeline also has been updated. Here are the latest numbers: DATE/TIME..DD...HH...MM...EVENT 05/19/00 06:12 AM...00...00...00...Launch 09:55 AM...00...03...43...NC-1 rendezvous rocket firing 09:52 PM...00...15...40...NC-2 rendezvous rocket firing 05/20/00 06:52 AM...01...00...40...NC-3 rendezvous rocket firing 08:09 PM...01...13...57...NC-4 rendezvous rocket firing 09:40 PM...01...15...28...Terminal rendezvous rocket firing 05/21/00 12:32 AM...01...18...20...Space station docking 10:47 PM...02...16...35...Spacewalk begins 05/22/00 05:02 AM...02...22...50...Spacewalk ends 08:12 PM...03...14...00...Space station ingress 05/23/00 06:42 PM...04...12...30...ISS reboost No. 1 begins 05/24/00 07:12 PM...05...13...00...ISS reboost No. 2 begins 05/25/00 07:12 PM...06...13...00...ISS reboost No. 3 begins 05/26/00 01:52 AM...06...19...40...Space station egress 03:07 AM...06...20...55...Station hatch closure complete 05:37 PM...07...11...25...Station undocking 07:23 PM...07...13...11...Final separation 05/29/00 01:15 AM...09...19...03...Deorbit ignition 02:19 AM...09...20...07...Landing Atlantis's preferred launch time, i.e., 6:12:15 a.m., comes 19 minutes before sunrise at the Kennedy Space Center. Under NASA flight rules, a launch is considered a "daylight" liftoff if it occurs 15 minutes before sunrise or 15 minutes after sunset. Thus, Atlantis's launching Friday - assuming it takes off on time - will be considered a night launch by just four minutes. An emergency return to the Kennedy Space Center, however, would occur in daylight, allowing NASA to use a 15-knot crosswind limit instead of the more restrictive 12-knot nighttime limit. At launch, the international space station will be located over 40.7 degrees north latitude, 32.5 degrees east longitude above a point northeast of Ankara, Turkey, near the Black Sea. =================================================================== Shuttle Atlantis cleared for Friday launch try (05/18/00) With forecasters fearlessly predicting a 100 percent chance of good weather, engineers are readying the thrice-delayed shuttle Atlantis for a fourth launch try Friday at 6:12:15 a.m., the opening of a five-minute 20-second launch window. The goal of the mission is to repair the electrical system aboard the international space station before arrival in July of a long-delayed Russian-built command module. "The countdown is going very smoothly," said launch director David King. "We're working no vehicle issues and no ground support issues that are going to keep us from trying to load the vehicle [with fuel] tonight. It's good to be back and we hope we're successful tomorrow morning." NASA managers will meet around 8 p.m. this evening to assess Atlantis's readiness for fueling. Assuming no problems crop up, engineers will begin pumping a half-million gallons of liquid oxygen and liquid hydrogen rocket fuel into Atlantis's external tank around 8:30 p.m. The tank should be topped off and in "stable replenish" mode by 11:49 p.m. Here's the rest of the countdown schedule: EDT........L-MINUS.EVENT HH:MM 05/18 04:45 PM...........Crew wakeup 06:00 PM...........Crew free time 06:33 PM...11:39...Launch danger area cleared 07:19 PM...10:53...Start 2-hour hold 08:19 PM...09:53...Mission management team meets for fueling go/no-go 07:49 PM...10:23...External tank ready for loading 08:19 PM...09:53...Start transfer line chilldown 09:19 PM...08:53...The countdown resumes 11:49 PM...06:23...Stable replenish 05/19 12:19 AM...05:53...Start a 2-hour built-in hold 01:00 AM...05:00...NASA television coverage begins 01:12 AM...........Astronaut photo opportunity on NASA TV 01:52 AM...........The astronauts don their pressure suits 02:19 AM...03:53...The countdown resumes after a two-hour hold 02:22 AM...........The astronauts depart crew quarters 02:52 AM...........The crew arrives at pad 39A 04:09 AM...02:03...Atlantis's hatch is closed for flight 04:54 AM...01:18...Cabin vent check 04:59 AM...01:13...White room closeout 04:59 AM...01:13...Start a 10-minute built-in hold at T-minus 20 minutes 05:09 AM...01:03...The countdown resmes 05:09 AM...01:03...Transition to OPS-1 launch software 05:14 AM...00:58...KSC area clear to launch 05:20 AM...00:52...An adjustable hold begins at T-minus nine minutes 06:00 AM...00:12...Mission management team final clear to launch 06:03 AM...00:09...Resume countdown 06:12 AM...00:00...Launch To pull off a successful rendezvous, Atlantis must take off within five minutes of the time when Earth's rotation carries launch pad 39A into the plane of the international space station's orbit. In theory, that would give the crew a full 10-minute launch window. But given the station's current orbit and altitude and a desire on NASA's part to conserve propellant aboard Atlantis for boosting the station's altitude, the actual launch window Friday will open 20 seconds before the moment the launch pad is exactly in the station's orbital plane. The window will close five minutes and 20 seconds later. Atlantis was grounded April 23, 24 and 25 by high winds at the shuttle's emergency runway at the Kennedy Space Center and at landing strips in Spain and Africa where the shuttle would have to attempt a landing in the event of a main engine failure at various points during the ascent. This time around, shuttle forecasters say conditions should be ideal, with light winds and no chance of rain. Despite initial predictions of possible problems at the overseas landing sites, meteorologist Ed Priselac said today conditions had improved dramatically. Overall, he said, there's no chance the weather will cause a delay Friday. Even so, NASA has booked Friday, Saturday and Sunday for launch attempts if necessary. But unlike the April campaign, when NASA made three attempts in a row to get Atlantis off the ground, King said today only two of the three days currently booked on the Air Force Eastern Range would be used. If NASA makes attempts Friday and Saturday, the team will stand down Sunday and top off on-board fuel supplies. A sixth launch attempt would be delayed until after Lockheed Martin makes another run at launching a new Atlas 3 rocket. The Atlas 3 was grounded Monday, Tuesday and Wednesday because of bad weather and problems with a radar tracking system in Bermuda. Robert Cabana, a veteran shuttle commander who now serves as a senior station manager, said the space station can remain in its current orbit through the end of May without having to use any of the limited on-board fuel supply. The Russian Zarya module, also known as the FGB, currently has about 2,200 kilograms of propellant on board. U.S. and Russian flight planners want to conserve that propellant if at all possible to permit at least two docking attempts with the new Russian command, or service, module, which is scheduled to arrive in July. "Right now, the space station is at approximately 180 nautical miles circular and our plan is to boost it up to approximately 203 nautical miles," he said. "That puts it at the right altitude so it will be in the proper place for an August service module launch. "We're planning on a July service module launch, so what we would do to adjust to get it to the correct altitude for the July launch is there are two planned burns on the FGB, test burns - 1 meter per second burns - to check out the systems. We'd orient the vehicle so those burns ... would put it at the correct altitude for the July launch. So we've effectively gained a good attitude for both a July and an August rendezvous with the service module at no cost in propellant on the FGB. "We're good pretty much through the end of May without having to do a burn on the FGB," Cabana said. "Even at the end of May it's not a problem. At that time, we'd use our propellant on board to boost to a higher orbit. But that's something we'd have to evaluate." Assuming Atlantis launches and boosts the station's altitude by 23 nautical miles or so, Zarya should have enough propellant to make two service module docking attempts with 400 kilograms of fuel left over. A detailed STS-101 flight plan revision is in work and will be posted here later today. =================================================================== Shuttle Atlantis rockets into orbit (05/19/00) 03:45 a.m. Update: Shuttle fueled, crew straps in for launch The shuttle Atlantis has been loaded with rocket fuel, the crew is strapped in and with forecasters calling for ideal conditions, NASA is hoping for an on-time liftoff this morning for an oft-delayed space station repair mission. Flight controllers at the Johnson Space Center in Houston have updated Atlantis's launch window based on radar tracking of the space station. The window will open at 6:09:29 a.m. and close at 6:16:10 a.m. The preferred launch time within that window is 6:11:10 a.m., one minute and five seconds earlier than NASA's previous update. A final launch time tweak may be made during a hold at the T-minus nine-minute mark. There are no technical problems with the shuttle, although engineers are troubleshooting a glitch with a launch pad computer system that governs the operation of high-speed film cameras used to document liftoff. There is no flight rule prohibiting launch without the movie cameras, but NASA managers have not yet finished discussing the issue. Photo documentation could be critical to investigators in the event of a launch mishap. But the system in question only affects film cameras; multiple video cameras remain operational. Otherwise, the weather is good in Florida and at the shuttle's three emergency runways in Spain and Africa. Atlantis was grounded April 24 and 25 by high winds in Florida and then again on April 26 by bad weather at the overseas runways. A fourth delay, from May 18 to 19, was ordered because of conflicts with an Atlas 3 launch campaign earlier this week. There are no such problems today. The STS-101 flight plan and the NASA television schedule will be updated after Atlantis takes off based on the shuttle's actual launch time. 06:20 a.m. Update: Shuttle Atlantis rockets into space Grounded three times last month by bad weather and once by conflicts with another rocket, the shuttle Atlantis's crew finally blasted off today on a high-priority mission to repair the international space station. Under a predawn sky, the black-and-white spaceplane vaulted away from launch pad 39A on time at 6:11:10 a.m., putting on a spectacular show for local residents and tourists lining area roads and beaches. If all goes well, the shuttle will dock with the space station early Sunday. The only technical issue discussed during ascent was a pressure reading from the shuttle's left-side orbital maneuvering system rocket pod. The crew was told no action was required and this does not appear to be a significant issue. Atlantis made the climb to space with what amounts to a new cockpit, the result of a major upgrade to replace the orbiter's outdated 1970s-vintage instruments with state-of-the-art flat panel displays. The new displays operate in full color using computer simulations of the old instruments that are being replaced. NASA is spending $220 million to upgrade all four of its space shuttles with the new displays and to upgrade simulators and other training systems at the Johnson Space Center in Houston. It cost about $9 million to upgrade Atlantis. The idea is to improve flight safety by making critical data more easily accessible. NASA eventually plans to add additional computer equipment to change the way diagnostic data is displayed on the new screens. The equipment presumably worked as advertised during Atlantis's climb to orbit today. Today's launch came just moments before Earth's rotation carried the launch pad into the plane of the international space station's orbit. Over the next two days, shuttle commander James Halsell and pilot Scott Horowitz will fire Atlantis's maneuvering jets in a carefully choreographed sequence to null out any difference in orbital planes, bringing the two spacecraft together Sunday at 12:31 a.m. as they pass above a Russian ground station. But the crew will not actually enter the station until Monday evening, after a spacewalk Sunday night by James Voss and Jeffrey Williams. During a six-and-a-half-hour excursion, Voss and Williams plan to mount a Russian cargo crane on the station's hull, replace a faulty NASA antenna and lock down a U.S. cargo boom that appears to be loose. Hatches between the two spacecraft will be opened at 8:12 p.m. Monday. A 3,800-word mission overview is available, along with a detailed sidebar describing Atlantis's new glass cockpit. The mission flight plan, television schedule and other timelines posted on the Current mission page will be updated as soon as possible to reflect the shuttle's actual launch time. 07:10 a.m. Update: Shuttle adjusts orbit for station rendezvous Shuttle commander James Halsell and pilot Scott Horowitz fired Atlantis's twin orbital maneuvering system rockets 44 minutes after liftoff today to put the spacecraft in the proper orbit for chasing down the international space station. The rocket firing put Atlantis in an orbit with an apogee, or high point, of 201.8 statute miles and a low point, or perigee, of 97.6 miles. The first in a series of space station rendezvous rocket firings, called NC-1, is on tap at 9:54 a.m. After that rocket firing, the orbit will measure 202.3 miles by 124.4. Four such firings are planned between now and Saturday evening when the final phase of the space station rendezvous will begin. "They say good things come to those who wait," launch director David King told reporters about 50 minutes after liftoff. "We waited for a while on this one, but the satisfaction is immense. It was awesome to get that mission off today. And what a beautiful time of day to launch, the vehicle going into the sunrise on ascent was awesome. I can imagine it must have been even more awesome on board. So we're excited about getting Atlantis launched today, it's been a long time coming." The STS-101 flight plan has been updated to reflect Atlantis's actual launch time. 07:15 p.m. Update: Astronauts begin first full day in space The Atlantis astronauts were awakened at 7:11 p.m. this evening to begin their first full day in space after a spectacular predawn launching from the Kennedy Space Center. The major items on the agenda this evening are checkout of the crew's on-board spacesuits, tests of the shuttle's 50-foot-long robot arm and two more rendezvous rocket firings to fine tune Atlantis's approach to the international space station. Docking remains on target for 12:31 a.m. Sunday. Here's the timeline for the crew's upcoming shift (in EDT and mission elapsed time): EDT........DD...HH...MM...EVENT 05/19/00 07:11 PM...00...13...00...Crew wakeup 09:41 PM...00...15...30...Spacehab activation continues 09:51 PM...00...15...40...NC-2 rendezvous rocket firing 10:36 PM...00...16...25...Airlock spacewalk preparation 10:56 PM...00...16...45...Rendezvous tools checkout 11:06 PM...00...16...55...Spacesuit checkout (1 and 3) 05/20/00 12:11 AM...00...18...00...Robot arm (RMS) powerup 12:26 AM...00...18...15...RMS checkout 01:06 AM...00...18...55...Spacesuit checkout (2) 01:11 AM...00...19...00...RMS payload bay survey 01:46 AM...00...19...35...RMS powerdown 02:11 AM...00...20...00...Crew meals begin 03:11 AM...00...21...00...Spacehab logistics transfer preps 03:30 AM...00...21...19...MISSION STATUS BRIEFING on NASA TV 03:51 AM...00...21...40...Ergometer setup 03:51 AM...00...21...40...Pre-ingress equipment setup; SOAR setup 04:46 AM...00...22...35...Centerline camera mount 05:16 AM...00...23...05...Orbiter docking system extension 06:00 AM...00...23...49...FLIGHT DAY HIGHLIGHTS reel on NASA TV 06:51 AM...01...00...40...NC-3 rendezvous rocket firing 09:11 AM...01...03...00...Crew sleep begins 05:11 PM...01...11...00...Crew wakeup 06:26 PM...01...12...15...Flight computer powerup 06:41 PM...01...12...30...Rendezvous timeline begins 08:08 PM...01...13...57...NC-4 rendezvous rocket firing 09:39 PM...01...15...28...Terminal phase rendezvous rocket firing 09:56 PM...01...15...45...Spacehab spacewalk preparation 05/21/00 12:31 AM...01...18...20...Space station docking The complete STS-101 flight plan is posted below, along with NASA's latest television schedule (rev. A). This status report will be updated throughout the night. The next NASA status report is expected around 8 p.m. It will be posted as soon as it's available. 11:00 p.m. Update: Detailed docking timeline posted For readers interested in such detail, a comprehensive space station docking timeline has been added to the STS-101 flight plan. The expanded docking timeline begins with the terminal initiation burn at 9:39 p.m. Saturday and ends at 12:47 a.m. Sunday - orbital noon - 16 minutes after docking. =================================================================== Shuttle closes in on space station (05/20/00) 04:10 a.m. Update: Astroanuts check out spacesuits; ready shuttle for docking The Atlantis astronauts checked out the shuttle's three spacesuits early today, set up and tested a battery of rendezvous tools and generally readied the orbiter for docking early Sunday with the international space station. They also unlimbered Atlantis's 50-foot-long robot arm and spent a bit of extra time putting it through its paces to get a feel for the differences between simulators on the ground and the real thing. The arm will be used overnight Monday during a planned spacewalk by astronauts James Voss and Jeffrey Williams. "The crew, from everything I could tell today, is chipper and doing great," said flight director Phil Engelauf. "They spent some extra time doing checkout of the RMS [robot arm]. We have several operators on board this flight who are qualified to use the arm, so we gave them a little bit more leeway in spending more time flying the arm to get a feel for that." The only technical problem of any significance - and it appears minor - involves Atlantis's left-side orbital maneuvering system rocket. The two OMS engines are used for major orbital adjustments and for the critical deorbit rocket burn used to drop the shuttle out of orbit at the end of a mission. During a space station rendezvous rocket firing Friday, telemetry indicated one of two propellant shut-off valves in the left-side engine may have failed to close properly. The engine is still operational and flight directors do not anticipate any problems with the deorbit burn. But to be on the safe side, upcoming space station rendezvous burns will be carried out using the right-side engine only. "One of the two engines, one of the ball valves, sort of the main shut off valves in the engine, failed to return to the fully closed position," Engelauf said. "There are two valves in series, the first one closed nominally and the engine shut down nominally. The second valve either did not close nominally or the sensor that detects the position of the valve did not return to the zero position. It shows the valve staying in the open position." The next space station rendezvous burn, one that would have been carried out with both OMS engines, is planned for around 6:51 a.m. "We're just going to replan that to be a single-engine OMS burn," Engelauf said. "That is easily within the capability of a single engine burn, it'll just be a little longer. The tricker issue is what you would do for downmode cases where you subsequently had a failure of the right OMS engine and had to complete that burn on the primary RCS (reaction control system jets). The burn time would be a little bit long ... and we would have to reschedule that as a two-part burn. But we don't expect any problems with the remaining engine and if we have to, we can always complete it with the primary RCS." Otherwise, there is little to report this morning. The crew is on schedule, the shuttle and its systems are "go" for docking and flight controllers are readying the international space station for the shuttle's arrival early Sunday around 12:31 a.m. "All systems on the ISS are performing well," said station flight director Paul Hill. "We're not chasing any anomalies besides the things we've already identified for repairs. We have started warmup on the FGB [Zarya module] and the [U.S. Unity] node. Both are progressing as planned. We've also started scrubbing the atmosphere inside the FGB and we'll start scrubbing the atmosphere inside the node after we get docked. Aside from that, the big thing on our plate will be activating the motion control system tomorrow about four orbits before docking. About an orbit after that, we'll go to the docking attitude and we'll wait for the shuttle crew to come up and dock." 06:00 p.m. Update: Astronauts begin final rendezvous with space station The Atlantis astronauts were awakened at 5:11 p.m. today for a long-awaited rendezvous and docking with the international space station. As of 6 p.m., the shuttle was within about 110 miles of the station, steadily closing in for a planned 12:31 a.m. docking. The final phase of the two-day rendezvous will begin at 9:39 p.m. this evening with a rocket firing that will begin the final phase of the orbital ballet. As with all such rendezvous, Atlantis will begin the final approach from a distance of about eight nautical miles behind the target. It will first fly beneath the station, then loop up directly in front and continue on until it is poised directly above the outpost. From there, commander James Halsell will manually guide the shuttle down to docking while the two spacecraft are within view of a Russian ground station. Here's a description by Halsell from a pre-launch NASA interview: "Actually, the rendezvous starts from the ground up in the sense that our liftoff has to be within about a 10-minute window in order to put us in the right place in the sky, below and behind the International space station," Halsell said in a NASA interview. "And for the next couple of days we will slowly catch up with it, doing burns as directed by the ground control center to optimize that catch-up rate. "On the morning of the third day, we'll wake up, have breakfast and if it's the same way as it was on STS-74, my other rendezvous mission, we might be able to look out the window and see a very bright star out in front of us, several miles, and that will be the international space station with the sunlight reflecting off of the solar panels. As the day goes on it'll get bigger and bigger, and then all of a sudden it won't be a star: It's going to be a discernible station with the solar panels that you can see. "As we get closer, the workload gets more intense," Halsell said. "About four hours prior to the actual docking we enter the rendezvous checklist, which is a very specific set of steps, maneuvers and burns to perfectly sneak up on, if you will, the space station. ... We're coming from below and behind, slowly coming up. About three or four thousand feet below and behind the vehicle, I'll actually move from the front seat to the aft cockpit and look through the overhead windows and I'll complete the maneuver for rendezvous manually from there. "We will come up below the station to about a range of 500 feet, and instead of coming straight up from that range, we will stop and then start a flyaround that will take us [to] 180 degrees on top of the station. From [there] we will complete the rendezvous and the docking by coming down from above." Here is a timeline of this evening's events: 06:26 PM...01...12...15...Computer powerup 06:41 PM...01...12...30...Rendezvous timeline begins 08:08 PM...01...13...57...NC-4 rendezvous rocket firing 09:39 PM...01...15...28...Terminal initiation burn 09:48 PM...01...15...37...Orbital sunrise 10:59 PM...01...16...48...Range: 1500 feet 11:04 PM...01...16...53...Range: 1000 feet 11:06 PM...01...16...55...Range: 800 feet 11:08 PM...01...16...57...Range: 650 feet 11:09 PM...01...16...58...Range: 600 feet (+Rbar; directly below station) 11:12 PM...01...17...01...Range: 500 feet 11:13 PM...01...17...02...Range: 400 feet (KU to low power) 11:16 PM...01...17...05...Orbital noon 11:23 PM...01...17...12...Range: 350-400 feet (+Vbar; directly in front ofr station) 11:35 PM...01...17...24...Range: 250 feet (-Rbar; directly above station) 11:39 PM...01...17...28...Range: 170 feet; start stationkeeping 11:44 PM...01...17...33...Orbital sunset 11:59 PM...01...17...48...Range: 170 feet; end stationkeeping 05/21/00 12:20 AM...01...18...09...Orbital sunrise 12:20 AM...01...18...09...Start stationkeeping at 30 feet 12:25 AM...01...18...14...End stationkeeping; push to dock 12:29 AM...01...18...18...DOCKING WINDOW OPENS 12:30 AM...01...18...19...Range: 10 feet 12:31 AM...01...18...20...Contact (station docking) 12:41 AM...01...18...30...DOCKING WINDOW CLOSES 12:47 AM...01...18...36...Orbital noon 12:51 AM...01...18...40...Orbiter docking system volume preparation 01:26 AM...01...19...15...ODS vestibule pressurization 01:51 AM...01...19...40...Spacewalk tools configured 02:26 AM...01...20...15...Computer powerdown 02:51 AM...01...20...40...SAFER checkout 04:06 AM...01...21...55...Procedures review 04:21 AM...01...22...10...10.2 depressurization 05:11 AM...01...23...00...Spacewalk review 09:11 AM...02...03...00...Crew sleep begins 05:11 PM...02...11...00...Crew wakeup The docking procedure is deliberately slow paced "because our vehicles are so large," Halsell said. "So all of these maneuvers are very slow, including the final docking, which takes place at a tenth of a foot per second, or if you want to round it off to something, one inch per second is about the rate that we're trying to make contact with as we come down on the international space station. We have several devices on board to help us gauge that. "The first is our eyes by looking outside and by virtue of the training that we've gotten here, we've gotten pretty good at eyeballing what a tenth of a foot per second is," he said. "But that's not our primary means. We have two laser systems, one fixed in the payload bay of the orbiter shooting up at the space station that gives us very accurate range and range rate. If that were to fail for some reason, I have Yury Usachev on the flight deck next to me who has a handhold laser not unlike what might be used by a police officer. Except it's using laser energy, not radar energy, to shoot at the international space station. The reflected energy can tell us, once again, the range and the range rate. So we have several different means of making sure that we dock precisely with the station." Once the two vehicles are locked together, the vestibule in the orbiter's docking system will be pressurized and the shuttle will take over attitude control for both vehicles. The astronauts then will set their sights on a spacewalk Sunday evening by astronauts James voss and Jeffrey Williams to install a Russian crane on the station's hull and to replace a faulty antenna on the U.S. Unity node. The crew will not open hatches between the shuttle and the space station until Monday evening. 09:41 p.m. Update: Shuttle rendezvous firing begins final approach to station The shuttle Atlantis's right-side orbital maneuvering system rocket fired this evening at 9:39 p.m. to begin the orbiter's final approach to the international space station. The burn began with Atlantis at a point about 49,000 feet behind the space station, clearly visible as a bright "star" in a black-and-white camera view from the Russian Zarya module. The station is oriented with the Zarya module facing Earth and NASA's Unity node module facing deep space. Atlantis will make its final approach from directly above, docking to a pressurized mating adaptor atop the Unity node at 12:31 a.m. Sunday. "Good burn, Atlantis. You're on your way," astronaut Chris Hadfield radioed from mission control in Houston after the terminal initiation burn was complete. See the next entry for a detailed look at this evening's rendezvous profile. 11:30 p.m. Update: Shuttle loops around station Space shuttle Atlantis has caught up with the international space station, passing below and then looping up in front of the orbital outpost. With one hour to go before docking, commander James Halsell is carefully maneuvering Atlantis to a point directly above the station. From there, he will guide the ship straight down to a linkup with a pressurized mating adaptor on the U.S. node module. There are no technical problems of any significance and docking remains scheduled for 12:31 a.m. Sunday. =================================================================== Astronauts dock with station; begin repair spacewalk (05/21/00) 12:50/02:55 a.m. Update: Shuttle Atlantis docks with space station Veteran commander James Halsell guided the space shuttle Atlantis to a gentle, on-time docking with the 35-ton international space station today as the two spacecraft sailed high above central Asia. Approaching the unfinished station from directly above, Halsell manually piloted Atlantis, its payload bay facing Earth, to a linkup at 12:31 a.m. to close out a two-day orbital chase. "Houston, we have capture," radioed Halsell as the docking mechanism engaged. "Roger, congratulations," replied astronaut Chris Hadfield from mission control in Houston. After a short pause to allow any relative motion to damp out, the shuttle's extended docking mechanism slowly retracted, firmly locking the two craft together. A few minutes later, Houston gave Halsell and company permission to take over attitude control of the combined vehicles, using the shuttle's maneuvering thrusters to keep both craft properly oriented in space. "It's hard to make it look any easier than the crew made it look today," flight director Phil Engelauf told reporters later. "This was really a textbook rendezvous, everything went virtually exactly per the timeline, per the procedures." Twenty minutes after docking, Halsell thanked the crew's trainers for properly preparing them for a difficult job. "I'd like to say thanks (to the training team)," Halsell radioed. "There's a little bit of hand shaking and back slapping going on back here. And this is just the first of several exciting days. Thanks for your help." "Atlantis, Houston, great work and thanks for the kind words," Hadfield replied. The trouble-free docking capped a near-perfect rendezvous that began with Atlantis's liftoff Friday from the Kennedy Space Center. The only departure from NASA's usual script was the use of just one of the shuttle's two orbital maneuvering system - OMS - engines for rendezvous rocket firings that typically would have been carried out with both. Questions about the status of a valve in the left-side OMS pod, however, prompted flight planners Friday to rule out any more firings by the left engine until the end of the mission. From Engelauf's perspective, it could not have been much smoother. "The procedures execution by the crew was virtually flawless," Engelauf said. "We flew the procedures on the approach just exactly by the book. We got to the station-keeping point, we got up to 30 feet, the angular alignment between the two vehicles was dead on, less than a degree in each axis, so no (corrective) fly-out was required. We pressed on in from 30 feet and docked with the station. The contact velocities were right on, a tenth of a foot per second, exactly as targeted. There were negligible lateral velocities or alignment errors. It just went exactly like it was supposed to, it was perfect. ... We're off to a great start, everything looks good so far." With docking behind them, the astronauts turned their attention to a spacewalk late this evening by astronauts James Voss and Jeffrey Williams to install a Russian cargo boom on the station's hull and to replace a faulty antenna on the Unity node module. The excursion is scheduled to begin at 10:31 p.m. and end around 5:01 a.m. Monday. The astronauts will not open hatches between the shuttle and the space station until Monday evening, finally floating inside around 8:11 p.m. "The node and the FGB (Zarya module) warmup are continuing for a flight-day five ingress and we're right on target," said station flight director Paul Hill. "At this point, we're really just ready to get on with the EVA (spacewalk) and four days worth of maintenance and repairs." 05:25 p.m. Update: Astronauts prepare for spacewalk Fresh from a picture-perfect rendezvous with the international space station, the Atlantis astronauts were awakened at 5:11 p.m. today to prepare for an overnight spacewalk before entering the station for the first time Monday night. Astronauts James Voss and Jeffrey Williams are scheduled to venture into Atlantis's cargo bay at 10:31 p.m. to mount a Russian cargo crane on the station's hull, to replace a faulty U.S. antenna and to lock down a loose American cargo boom that was installed during an assembly flight last year. If all goes well, the excursion will end around 5 a.m. Monday. "Good morning Atlantis!" astronaut Steve Robinson called from mission control after the crew's morning wakeup call. "A little Stevie Ray Vaughan to wake up Jeff and Jim here on EVA day. The song ("Lookin' Out the Window") kind of says it for us, we'll soon be looking at that window at you guys." "Good morning, Houston," Williams replied. "We're up and wide awake and ready to go and looking forward to checking the view from outide of the ISS and shuttle docked together after that wonderful rendezvous yesterday." "Good to hear from you, Jeff," answered Robinson. "We're all primed and looking forward to an exciting day." Here is a timeline of upcoming events: 05/21/00 05:11 PM...02...11...00...Crew wakeup 07:11 PM...02...13...00...Spacewalk preparations begin 08:41 PM...02...14...30...Voss and Williams breathe pure oxygen to purge nitrogen from their bloodstreams; this will help prevent the bends after donning their 5 psi spacesuits 09:56 PM...02...15...45...The shuttle's robot arm is powered up 10:06 PM...02...15...55...Airlock depressurization begins 10:31 PM...02...16...20...Voss and Williams exit Atlantis's airlock 10:46 PM...02...16...35...Tools and work platforms are set up 11:16 PM...02...17...05...Voss and Williams lock down a loose U.S cargo boom 05/22/00 12:31 AM...02...18...20...The spacewalkers begin installation of a Russian cargo boom 02:16 AM...02...20...05...A faulty antenna on the U.S. Unity node is replaced 03:16 AM...02...21...05...Voss and Williams install handrails 03:41 AM...02...21...30...14.7 cabin repress 03:46 AM...02...21...35...Voss and Williams pack up their tools 04:41 AM...02...22...30...Robot arm powerdown 04:46 AM...02...22...35...The spacewalkers return to the airlock 05:01 AM...02...22...50...Airlock reprssurization 08:56 AM...03...02...45...Crew sleep begins 04:56 PM...03...10...45...Crew wakeup 07:56 PM...03...13...45...Daily briefing 08:11 PM...03...14...00...Space station ingress Voss, a veteran spacewalker, will spend months aboard the international space station next year as a member of the lab's second full-time crew. His two space station crewmates, also aboard Atlantis, are Susan Helms and cosmonaut Yury Usachev. During the spacewalk, Voss will spend most of his time anchored to the end of Atlantis's robot arm while Williams works from portable work platforms mounted where necessary. "When Jeff and I go outside, we will be transferring over some things from the space shuttle onto the station," Voss said in a NASA interview. "One of the things is a crane - it's called the Strela, it's a Russian piece of hardware, it has an extendable boom that you can use for moving people or equipment around on the space station. A piece of it is already up there; we're bringing up the boom itself and an extension to the boom. We'll assemble pieces of it in the payload bay of the space shuttle, and then we will move it up to the space station, assemble it there, and then we'll move the entire thing over to a new location where it's kind of out of the way for future construction that's going to happen. After we've moved the Strela, then we have some other tasks that we have to complete," Voss continued. "There are some handrails we're going to install, a cable for a centerline camera for future docking flights, and we've got something that's been added fairly recently, and that's a repair or, a look at possibly repairing a U.S. crane that we put up there on the last flight. "There is something that is not working quite right on it; it's rotating freely - and we're going to look at the interface where this crane plugs into a socket on the space station and see if we can fix it. Now, we have several different things we might try: hopefully the easiest thing is just take it out, put it back in again and it'll lock in place this time. And if it doesn't, then we have other contingencies of trying other places or perhaps even bringing it into the station so that we can look at the mechanism and see what's wrong with it." Voss and Williams also plan to replace an antenna on the U.S. Unity node. The antenna, part of an interim communications system that lets flight controllers in Houston monitor station systems until the U.S. laboratory module arrives, has degraded in recent months. "We have a communications antenna on the space station that's called the early comm or early communications system, and one of those antennas - one of the two - has had part of it that's failed," Voss said. "They're still able to use a piece of it, but it's not fully functional. So we're going to change out one of those. "Luckily, it's one of the tasks that I was already doing part of for our space station flight that we were scheduled for, so this was a relatively easy one for me to train for. And we will change out that antenna, just replace it with an identical one, and bring back the old one for repair." Williams, making his first shuttle flight, said before launch he was excited to be doing a spacewalk. In fact, he said, "the greatest honor of this flight assignment and the mission is the opportunity to go EVA." While successfully completing his assigned tasks is his top priority, Williams said "I want to pause and enjoy the experience and realize where I'm at and what I'm doing and the experience of that. So, I don't want to lose that. I will be managing all my little pieces of equipment and hardware in very great detail, but also take the time to look around and see the creation below me." 07:15 p.m. Update: Spacewalkers running ahead of schedule Astronauts James Voss and Jeffrey Williams are running about 25 minutes ahead of schedule this evening as they prepare for an overnight spacewalk. If their current pace holds up, the spacewalk will begin a few minutes past 10 p.m. For readers with access to NASA television, here are the latest windows during which live TV from Atlantis is possible (all times in EDT): WINDOW OPEN....WINDOW CLOSE 09:49 p.m......10:41 p.m. 11:24 p.m......12:17 a.m. 12:59 a.m......01:55 a.m. 02:38 a.m......02:54 a.m. 03:17 a.m......03:37 a.m. It does not appear any live television from the shuttle will be possible after 3:37 a.m. until later in the morning, after the spacewalk is over. As always, such times are subject to change. 10:10 p.m. Update: Voss and Williams begin spacewalk Astronauts James Voss and Jeffrey Willliams officially began a planned six-and-a-half hour spacewalk this evening at 9:48 p.m. when they switched their spacesuits to internal power in the shuttle Atlantis's airlock. The spacewalkers are running about 43 minutes ahead of schedule. Here's a rough timeline of this evening's activities based on the actual airlock egress time: 09:58 PM...Airlock egress 10:13 PM...Sortie setup 10:43 PM...U.S. crane lockdown 11:43 PM...Strela crane setup and installation 01:43 AM...Node antenna replacement 02:43 AM...Node handrails installation; centerline camera cable 03:13 AM...Sortie cleanup 04:13 AM...Airlock ingress 04:28 AM...Airlock repressurization 10:45 p.m. Update: U.S. cargo boom found loose as expected; removed and successfully reseated Astronauts James Voss and Jeffrey Williams accomplished the first objective of their spacewalk tonight by locking down a loose U.S. cargo boom installed on the space station last year. The locking mechanism at the base of the telescoping crane, which will be used by future station assembly crews to hold replacement parts, assembly tools and other gear, apparently worked its way loose after the astronauts who installed it departed. Voss and Williams simply pulled the crane out of its mounting bracket and reseated it, making sure they fully engaged the locking mechanism. "I'm going to try going to lock right now. ... I'm going to push on it a little bit," one of the spacewalkers said, grunting. "OK, I think I have it in lock." "Try a pull test and a twist," a crewmate suggested. "It does not rotate at all." "Very good, good job!" The spacewalk is proceeding on schedule with the astronauts now turning their attention to assembly and installation of a Russian cargo boom that will be used by future assembly crews. =================================================================== Spacewalk ends; astronauts enter space station (05/22/00) 12:35 a.m. Update: Spacewalkers ahead of schedule Astronauts James Voss and Jeffrey Williams are breezing through a planned six-and-a-half-hour spacewalk this morning. As of 12:20 a.m., they were running nearly one full hour ahead of schedule, successfully remounting a loose U.S. cargo boom on the hull of the international space station and assembling a new Russian crane that will be used by future construction crews. "This hardware works great," one of the spacewalkers said of the Russian "Strela" crane. "The folks at Energia built a good piece of hardware." Part of the Russian boom was installed on the station during the last shuttle visit in May 1999. On this mission, the crane is being completed and moved from an interim location to a mounting point on a pressurized tunned connecting the U.S. node module and the Russian Zarya module. "We've found that our EVA trainers did a great job, we're moving right along with this stuff," Voss radioed Houston. "Yeah, they sure did," Williams agreed. "Thanks, we'll pass that along," astronaut Chris Hadfield replied from mission control. A few minutes later, pilot Scott Horowitz, serving as a spacewalk director of sorts inside Atlantis's crew cabin, told Voss and Williams to take a break. "Hey, you guys are way ahead of schedule," he called. "If you want to take a breather for a minute or two, get your camera out, take a picture of that Strela closeup installed, that'll fill that square, then translate back and continue on." 02:10 a.m. Update: Faulty antenna replaced; node handrails installed Spacewalker's James Voss and Jeffrey Williams, four-and-a-half hours into a space station repair and upgrade job, have replaced a faulty antenna on the U.S. Unity node module and are in the process of installing eight handrails on the node's outer hull for use by future space station assembly crews. This is the last major task of this morning's spacewalk. Voss and Williams are running more than an hour ahead of schedule and if they keep up this pace, the spacewalk will wind up between 3:30 a.m. and 4 a.m. 04:33/05:45 a.m. Update: Spacewalk ends; all objectives accomplished Astronauts James Voss and Jeffrey Williams completed a successful six-hour 44-minute spacewalk this morning, mounting a Russian cargo crane on the international space station's hull, locking down a loose U.S. cargo boom installed last year and replacing a faulty antenna. They also installed eight handrails on the exterior of the U.S. Unity module, moved a cable bundle that was obscuring an optical target and attached a television camera cable that will be used for future shuttle dockings. Voss, who will spend five months aboard the space station next year as a member of its second full-time crew, thanked the NASA trainers who prepared "Thanks to the whole team," he said. "It was a good job by everyone making this happen. And for me, it was a particularly meaningful experience coming up here and helping to assemble the space station that's going to be my home next year for about five months. So it was really great for me, thanks to everyone." "And Jeff and Jim, you certainly did an outstanding, professional job up there paying off all the work all those folks put into this," replied astronaut Mario Runco from mission control. "We appreciate it from down here. And Jim, it must be nice to be able to work on your own house there for a while." "It sure was, Mario." The excursion began at 9:48 p.m. Sunday when the astronauts switched their spacesuits to internal power. It officially ended with the start of airlock repressurization at 4:32 a.m. Shuttle astronauts have now spent 304 hours 37 minutes walking in space in 49 excursions. This was the fifth space station assembly spacewalk, pushing the station total to 36 hours and one minute. "We had a very successful EVA tonight," said chief flight director Jeff Bantle. "Obviously, all the planning and effort that went in from the training folks on the ground to the crew was very successful and we accomplished all the tasks." Voss and Williams ran more than an hour ahead of schedule at some points but they lost the time back getting a balky handrail installed and repositioning the U.S. cargo boom at the request of Russian flight controllers. The Russians were concerned the boom might block one or more antennas on the Russian Zarya module had it been left where it was. Spacewalk trainer Scott Bleisath said this sort of spacewalk will become routine in the months ahead as station assembly accelerates. "This spacewalk was a good example of what future spacewalks are going to look like, where we will need to perform maintenance on the space station," he said. "Throughout the assembly and operational life of the space station, we'll be sending out crews to perform maintenance and the tasks you saw tonight with the U.S. crane and the replacement of the early communications example is a real good example of how those tasks will be done on future spacewalks." With the spacewalk behind them, the Atlantis astronauts will open hatches between the shuttle and the station around 8:11 p.m. this evening to kick off long-awaited work to replace ailing batteries aboard the Russian Zarya module. Four of six batteries will be replaced, along with associated electronic gear. "We'll be ingressing the station around (8 p.m.) tonight and we'll start our battery swapouts around (12:15 a.m.)," Bantle said. "The mission's going very well and any problems we have are extremely minor. The shuttle orbiter is in extremely good shape. The ISS is performing very well for us and we're looking forward to repairing the battery systems over the next couple of days." 06:00 p.m. Update: Astronauts awakened; space station entry on tap The Atlantis astronauts were awakened this afternoon at 4:56 p.m. for a busy day that will begin just after 8 p.m. when they float into the international space station to begin repairing the lab's ailing electrical system. For James Voss, Susan Helms and cosmonaut Yury Usachev, scheduled to spend three to four months aboard the station next year as its second full-time crew, entry will mark a chance to inspect what will soon be their home in space. "Good morning Atlantis! Greetings and welcome from the station control centers in Houston and Moscow," radioed Mike Fincke from the space station control center in Houston. "It's been about a year since we've had company so we're glad you're here. But we'll have to put you to work. And a special welcome to your new house to Yury, Susan and Jim." "Thanks a lot," commander James Halsell radioed. "We're anxious to get in there and get to work." "Well, we've got a lot of work for you to do today." Usachev, Helms and Voss were added to Atlantis's crew in February specifically to help with the Zarya repair work. "This will be an excellent training opportunity for us," Voss said. "Our simulators that we're going to train in finally for our long-duration flight are not quite ready yet. So this is a chance for us to go up and see the real thing and train on it by changing out hardware and operating in there. So it's going to be wonderful preparation for our long-duration flight." Added Helms: "All three of us will be doing the kind of things on this mission that we're going to be doing on the increment mission. Jim will get a chance to crawl around outside the station in an EVA [spacewalk], Yuri and I will be digging around inside the space station doing maintenance tasks and these are the kinds of things you would expect us to do during increment two. In fact, they're planned events. Not only that, we're also refreshing on a lot of things working together with the shuttle that also will be helpful to know now, like how the shuttle guys come up and do [equipment] transfers." Atlantis docked with the space station early Sunday, but the astronauts did not immediately open hatches between the two spacecraft in order to stage a spacewalk Sunday night to install equipment on the station's hull and to make a few minor repairs. By leaving the hatches closed, Atlantis could quickly undock in an emergency. In its current configuration, the station consists of two modules: The U.S. Unity node and the Russian Zarya propulsion module. The two are connected by a pressurized tunned called PMA-1. Another pressurized mating adaptor - PMA-2 - is mounted on the other end of Unity. Atlantis is docked to PMA-2. After entering the station this evening, the astronauts will methodically make their way through the U.S. node and into Zarya around 10:11 p.m. Here's a bit of background from the CBS News mission preview posted at the bottom of this page: The first item on the agenda is replacing batteries one, two, three and five in Zarya. In addition, four charge-discharge control devices known as PTABs - a Russian acronym - will be replaced, along with two control boxes called BUPTs. The batteries and associated gear are mounted in "slots" behind panels in the Zarya module. The electrical repairs will be made primarily by Usachev, Helms and Voss. It will take about an hour or so to replace a battery, BUPT and PTAB. Work in slots one and two will be carried out immediately after station entry. The rest of the work will be spread out over the next two days. "We'll start with slot one and two on our first ingress day," said station flight director Paul Hill. "We'll replace the battery, PTAB and BUPT in slot one all in about a single hour's worth of activity and we'll get that equipment charging. It'll take us on the order of 20 to 24 hours to charge that battery up so it can support the main bus. "Once it's charging, the crew will then go under the floor for slot two and the plan would be to get the battery and the PTAB both changed out before the crew goes to bed. ... We can only charge one of these batteries up at a time. Once battery one finishes charging, we'll bring it onto the main bus. As soon as it's connected, we'll start charging battery two and we'll disconnect battery three so we can replace the PTAB and BUPT and also the battery. This will ripple down through the flight." Along with repairing the station's electrical system, the astronauts also plan to replace several fans and smoke detectors to improve performance or correct earlier failures. In addition, part of Zarya's radio telemetry system is on the blink and will be replaced. As with all shuttle-station missions, fresh water generated by the shuttle's electrical generators will be transferred to tanks on the station for future use along with other supplies needed by the first full-time crew - commander William Shepherd, Sergei Krikalev and Yuri Gidzenko - scheduled to arrive in late October. That gear includes a treadmill, a printer, trash bags, clothing and equipment to help the crew stow loose gear. The astronauts also will install new smoke detectors and fans to improve air circulation and to help keep CO2 levels down. The previous shuttle crew to visit the station reported problems with air quality and apparently suffered headaches and other ailments as a result. "They did a lot of analysis in terms of the air flow, the ventilation, the air flow between the ISS and the shuttle after the last mission," Halsell said. "And they've taken some measures that we will implement after we first ingress to change the ventilation and hopefully improve the circulation of the air between ISS and the shuttle. "Obviously, the shuttle is what's scrubbing out the CO2 and removing humidity. We believe that, in addition to some additional fans we will have, will improve the overall circulation as well as improve the local circulation around each individual. Hopefully we won't experience those same problems." After the service module is in place, the air will be cleaned by on-board systems. "Once the station is operating, it will have a system to scrub out carbon dioxide," said Weber. "It's not there yet. It was never designed to have the shuttle at one end scrubbing out the whole air system. So this is an artificial situation, these are the last flights where this is going to be the case." High noise levels in the Russian Zarya module are another problem reported by the previous crew. Robert Cabana, commander of the first space station assembly mission and now a NASA manager, said the service module will be modified to prevent health problems for future full-time crews. Atlantis's crew, meanwhile, is equipped with high-tech earplugs. "We have put in place plans to decrease the noise levels and we're going to start testing in the service module in April," he said. "We'll see how well our design changes actually reduce the noise levels. We're looking at improved fans that will be retrofitted later on. In the meantime, we're going to have to provide hearing protection for the crew." Overall, he added, "I think we've got a good program in place. I don't think it's going to be a long-term problem for the space station. It's something we have to deal with right now." Amid work to refurbish Zarya and to transfer supplies, Halsell and Horowitz will fire Atlantis's maneuvering jets three times over three days - for a total burn duration of two-and-a-half hours - to boost the station's altitude by about 20 miles. 08:20 p.m. Update: Astronauts enter space station The Atlantis astronauts opened a hatch between the shuttle's docking system and the international space station at 8:03 p.m. this evening to officially open the outpost for four days of repair work. As of 8:15 p.m., astronaut Susan Helms and cosmonaut Yury Usachev were equalizing pressure between a pressurized mating adapter and the U.S. Unity module before entering the station proper. The crew has been cleared to proceed directly to the Russian Zarya module to begin work replacing batteries and other electric al gear. This page will be updated throughout the night as the repair work progresses. =================================================================== Station reboost begins; third battery changed out (05/23/00) 12:30 a.m. Update: First new battery installed in Russian module Four-and-a-half hours after entering the international space station, astronaut Susan Helms and cosmonaut Yury Usachev had completed installation of a new battery, a fresh charge-discharge unit and a computer controller in the Russian Zarya module. They plan to install a second battery and another charge-discharge unit before calling it a day later this morning. Two more batteries, two more chargers and at least one additional computer controller will be installed Tuesday and Wednesday. Video from the space station showed Helms and Usachev floating above the first battery compartment, making sure various electrical connectors were firmly seated. The work went smoothly and the astronauts had no problems of any significance. Each new battery will be fully charged before being brought on line. The last crew to visit the space station in May 1999 reported foul air and uncomfortably loud background noise in the station. The Atlantis astronauts set up improved air ducts and fans after entering the station Monday night and said air quality was just fine. While the initial temperature was high enough to prompt flight engineer Jeffrey Williams to work topless most of the evening, his crewmates appeared comfortable, reporting a few hours after ingress that conditions were improving as the air circulation system picked up the load. Humidity levels were within limits and carbon dioxide readings were well below danger levels. "That's a great reading, we're happy with the CO2 level," astronaut Chris Hadfield radioed from Houston. As for high noise levels, NASA and Russian engineers are installing additional insulation and other noise-abatement measures in new modules awaiting launch. Atlantis's crew is equipped with ear plugs, but the astronauts reported the ambient noise level was not particularly uncomfortable. 05:30 p.m. Update: Astronauts gear up for second day of station repair The Atlantis astronauts were awakened at 4:41 p.m. this afternoon for a second day of space station repair work. This evening, the crew will install fire extinguishers, dust filters, new fans and smoke detectors in the station to improve air quality and to beef up safety systems. Station ingress is on tap around 7:41 p.m. The astronauts also will carry out the first of three reboost maneuvers in which Atlantis's steering jets will be fired, or pulsed, up to 27 times in one hour to increase the station's altitude. This evening's reboost should raise the station's altitude by about nine miles. When all three reboost maneuvers are complete, the station's orbit will have been raised more than 20 miles. The rocket firings are needed because recent solar activity has caused Earth's atmosphere to expand slightly, which produces a braking effect on satellites in low-Earth orbit as they sail through the extreme upper atmosphere. Before Atlantis's arrival, the station was falling some two miles per week. By using spare propellant aboard Atlantis to reboost the station, flight controllers can avoid burning up precious fuel in the Russian Zarya module's propulsion system and protect against the possibility of additional unexpected altitude shortfalls before the arrival of a new command module in July. "Our strategy is to go as high as shuttle prop margins will support," said station flight director Paul Hill. Here is a timeline of this evening's activities (in EDT and mission elapsed time): DATE/TIME..DD...HH...MM...EVENT 05/23/00 07:11 PM...04...13...00...Daily crew planning session 07:41 PM...04...13...30...Station ingress 07:51 PM...04...13...40...Fungus search and destroy 07:51 PM...04...13...40...KOMP cable installation 07:56 PM...04...13...45...ISS reboost No. 1 start 08:51 PM...04...14...40...Fire extinghuisher R&R begins 09:06 PM...04...14...55...Zarya dust filter No. 1 replacement 09:06 PM...04...14...55...Zarya fan No. 3 replacement 09:21 PM...04...15...10...Zarya dust filter No. 2 replacement 09:51 PM...04...15...40...Zarya fan replacement 10:11 PM...04...16...00...Smoke detector No. 1 replacement 10:41 PM...04...16...30...Smoke detector No. 5 replacement 11:41 PM...04...17...30...Crew meals begin 05/24/00 12:16 AM...04...18...05...Smoke detector No. 6 and 8 replacement 12:41 AM...04...18...30...Smoke detector No. 7 replacement 12:41 AM...04...18...30...Williams and Voss field questions from CNN Armed Forces TV and space.com 01:16 AM...04...19...05...RFPDB replacement 01:31 AM...04...19...20...ZRU-3 R&R (Battery A73) 01:31 AM...04...19...20...ZRU-3 R&R (BUPT); ZRU-3 R&R (PTAB) 01:41 AM...04...19...30...Label nitrogen and oxygen lines 02:30 AM...04...20...19...Mission status briefing on NASA TV 02:51 AM...04...20...40...Smoke detector No. 9 replacement 04:11 AM...04...22...00...Zarya fans 1 and 5 replaced 04:41 AM...04...22...30...Smoke detectors 2 and 3 replacement 08:26 AM...05...02...15...Crew sleep begins 04:26 PM...05...10...15...Crew wakeup Williams and Voss will field questions from reporters with CNN, Armed Forces Television and space.com starting at 12:41 a.m. A mission status briefing is on tap at 2:30 a.m . This status report will be updated after both events or as warranted throughout the night. 03:10 a.m. Update: NASA managers please with station environment Work to improve air circulation aboard the international space station has apparently paid off with low C02 readings and no reports of any adverse health effects from the crew. During the most recent previous space station visit in May 1999, astronauts reported stale air in parts of the station and symptoms of high carbon dioxide concentrations. This time around, the Atlantis astronauts employed a different ducting scheme to more thoroughly scrub the station's air through the shuttle's filtration system and to ensure good mixing back in the station. The space station currently is made up of two large modules: The Russian Zarya propulsion module and NASA's Unity node, a multi-hatch module that will serve as a gateway to future station components. The two modules are connected by a short tunnel called a pressurized mating adapter, or PMA. Another such PMA connects the shuttle to the node. The goal was to ensure that air in the Zarya module, which is farthest from the shuttle, is forced into the orbiter's filtration system. "We did make some changes to how we routed some of the ducting so that we improved air exchange between the FGB (Russian Zarya module) and the node and the orbiter where all the air scrubbing is done," said station flight director Paul Hill. "We've done a lot of work to make sure we have improved what air scrubbing, or air exchange, we're doing with the station to make sure we don't have any stale air back there. We've also provided a number of portable fans the crew can set up at whatever work site their in. (But) we have had no reports (of bad air quality)." Shuttle flight director Phil Engelauf agreed, saying "we haven't seen any indications of adverse effects or poor air quality and with the conditions we think we've created with these ducting mods, we're optimistic we'll keep the air as good as we can possibly make it in the station." When the astronauts entered the space station shortly after 8 p.m. Monday, temperatures in the Zarya module were around 75 degrees. It was a much warmer 86 degrees in the Unity node, hot enough to prompt astronaut Jeffrey Williams to doff his shirt. But Hill said that was an expected, short-term effect and no problem for the crew. "It was a little bit warm in the node, the crew was getting a little bit hot," he said. "That's not necessarily unexpected. We hadn't established ventilation or air exchange with either the shuttle or the FGB right away (and) we spent several days warming up the shell to prevent condensation. "So it did start out a little warm in there," he said. "The node is already cooling down to a more comfortable temperature level. Now that we're inside and we know we have the shell warmed up, we've also dropped some of our heater power to make sure we keep it at a more comfortable level for them. From every other perspective, the station looked good inside." By 3:15 a.m., the astronauts had changed out one of Zarya's ailing batteries and were wrapping up replacement of a second. They also replaced two charge-discharge units and one battery controller. The work went much faster than expected with no problems of any significance. "The day started off very well," Engelauf said. "The crew was aggressive and got a little bit of a head start on the ingress activities this morning. We worked our way through the PMA and into the node and all the way on into the FGB well ahead of the timeline for the day and the crew was able to get through all the ducting reconfigurations, take all the air samples and go ahead and get started on the electrical power system component changeouts well ahead of the schedule. "We made up roughly about an hour on the timeline," he said. "Everything went perfectly today. All the scheduled activities were completed, there were no particular problems. ... The crew's well ahead of schedule and we're making good progress." Said Hill: "Everything's going as planned, it couldn't be going better for us." 09:30 p.m. Update: Reboost operation complete; adding television windows Commander James Halsell and pilot Scott Horowitz fired Atlantis's steering jets 27 times in 59 minutes this evening, raising the international space station's orbit by an average of 9.7 statute miles. The rocket firings began at 8:02 p.m. and ended at 9:01 p.m. When the burns started, the station's orbit measured 208 miles by 203 miles. When the maneuver was complete, the orbit's apogee, or high point, was 219.5 statute miles and its perigee, or low point, was 212.3 miles. Two more reboost maneuvers will be staged Wednesday and Thursday to boost the station's orbit by a total of about 27 miles. In the meantime, space station planners are expected to delay Atlantis's undocking from the space station Friday by one orbit - from 5:32 p.m. to around 7:09 p.m. - to improve communications through Russian ground stations. Before launch, mission managers held open the possibility of extending Atlantis's flight by one day to give the crew additional time to complete a variety of station repair the restocking tasks. But based on the crew's initial success staying ahead of the timeline, a mission extension now appears unlikely. An official decision along those lines is expected later this week. For readers with access to NASA television, here are the available windows this evening for live downlink video from Atlantis (in EDT): WINDOW OPEN...WINDOW CLOSE 10:55 p.m.....10:58 p.m. 11:06 p.m.....11:58 p.m. 12:15 a.m.....01:34 a.m. 02:17 a.m.....03:10 a.m. 03:53 a.m.....04:49 a.m. 05:32 a.m.....06:31 a.m. 07:12 a.m.....07:34 a.m. NASA television is carried live on the internet by The Houston Chronicle. =================================================================== Batteries installed; technical issue resolved (05/24/00) 01:30 a.m. Update: Astronauts put to rest concerns about station environment Putting to rest any lingering concerns about living conditions aboard the international space station, Atlantis commander James Halsell said today it's quieter aboard the station than the shuttle and that air quality, a concern since the last shuttle visit in 1999, "has been outstanding." "We've had no operational impacts at all as a result of poor air quality," Halsell said. "The air has been just fine. It is true that when we first moved into the station the room here (in the Unity module) was slightly warm. But it cooled down just as soon as we were able to get all the hatches open and all the air ducts in place and the ventilation going. "In general, the air quality has been outstanding," he said. "With regard to the noise, I was surprised. I had heard everybody's comments about how to expect loud noises. It is, in fact, quieter here than it is on board the shuttle and the shuttle is quiet enough to meet all the OSHA standards. So we have not experienced any problems with regard to living conditions on board the station." Three of Halsell's crewmates - cosmonaut Yury Usachev, Susan Helms and James Voss - plan to spend three to four months aboard the station next year as the lab's second permanent crew. Halsell said all three now know what to expect and "they're enthusiastic about returning as a crew on board the station." The last crew to visit the station reported pockets of stale air and symptoms from exposure to high carbon dioxide levels. The Atlantis astronauts implemented a few relatively simple fixes to alleviate the problem. "There was a lot of concern about the air quality before we came up on this mission," said pilot Scott Horowitz. "As everybody knows, the last mission had a few problems with the air quality. All the folks who did the design and modification of our air ventilation system put their heads together and came up with some fairly simple mods. "We just modified the position of a few valves, changed some of the duct work inside and added a few personal fans and that seems to have done the trick by re-routing the air," he said. "After we opened up the station, I noticed the air quality improved probably 100 percent after just a few hours." As for the predicted high noise levels aboard the station, Horowitz said "it just sounds to me like a little bit of humming, motors in the background, actually. The noise level is a lot less than what I thought it would be. ... It's not very loud, I think all the insulation we've put on has helped a lot." To prove his point, Horowitz keyed his microphone open and held it at arm's length in the center of the Unity module. The background noise could be heard, but it did not sound uncomfortable. The astronauts are equipped with high-tech earplugs that can filter out specific frequencies. But so far, it does not appear the crew has needed to use them. "No, it's really the same as the shuttle," said astronaut Mary Ellen Weber. "We have to use fans to keep the air moving when there isn't any gravity. So we have fans in the shuttle and we have fans here as well." Halsell told a reporter shuttle mission STS-101 was a "payoff" flight to the crew, a voyage "with a little bit of everything you can do in a spaceflight, including the ascent of course, which is exciting in and of itself, but then the rendezvous, the flyaround and then the final docking, the spacewalk following that and then the day following that, opening up the hatches and coming on board the space station and going to work on it. It is indeed the payoff flight." Said Horowitz: "It kind of brought a flashback, if you will, to when I was a kid and saw "2001" (A Space Odyssey) and the scenes where you see the shuttle docking with the large station. This one's not nearly that big yet, but it's going to keep getting bigger over the next couple of years and it's going to be quiet a place to come visit." As of 1:30 a.m., Voss, Helms and Usachev were busy installing a third replacement battery in the Russian Zarya module. The crew continues to make good progress and there are no technical problems of any significance. 03:15 a.m. Update: Engineers troubleshoot possible battery problem Russian engineers are troubleshooting a possible problem with one of the new batteries installed aboard the international space station by the crew of shuttle Atlantis. Preliminary indications are the battery is healthy and that it began discharging prematurely because of procedural problems or a commanding error or conflict. The battery has been reconnected to its charger and engineers are monitoring its performance. The Atlantis astronauts are in the process of replacing four of Zarya's six batteries - Nos. 1, 2, 3 and 5 - along with associated charge-discharge control circuitry. Battery 1 was installed overnight Monday, charged up for nearly a full day and put on line. It is operating normally. Battery 2 was installed overnight Monday as well, but each powerpack must be charged up individually. After just two hours of charging overnight, battery 2 suddenly began discharging. Russian flight controllers quickly took the battery off line while they studied the issue. Battery 3, meanwhile, was installed early this morning. It is not scheduled to be charged until late today or early Thursday. Battery 5 will be installed early Thursday. Space station flight director Paul Hill told reporters during NASA's morning status briefing that it's too early to say whether battery 2 has a real problem or whether some other factor triggered the early discharge. But even if the battery turns out to be bad, he said, Atlantis has what amounts to a spare on board. Two, in fact. "We essentially do have a spare for the spare on board," he said. "And that would be the best of the batteries that we're taking out now and that would be battery 5. If for some reason we isolated what we're seeing right now in battery 2 to be a real battery problem and we did not want to leave that battery installed, we have the option of going back and continuing to use that battery that's in slot 5, not to mention going back and re-assessing the battery we took out of slot 2. "There's been much discussion this spring as to whether or not there was something wrong with that battery in the first place," Hill said. "We know that we had a hard failure in PTAB-2 (the battery's charge-discharge unit). There is some discussion that battery 2, if we were to bring it back on line, would function. Because we had some concern for the amount of time that battery's been in orbit without being used at all, we elected to replace it. If we decide here in the next couple of days that the new battery really is a problem, we could either go back to the old battery 2 or the old battery 5." To date, the astronauts have transferred 1,196 pounds of equipment to the space station from Atlantis and moved another 675 pounds of gear from the station to the shuttle for return to Earth. By the end of the mission, the 35-ton station will be 2,118 pounds heavier than it was when Atlantis showed up Sunday morning. "We're 100 percent successful so far," Hill said. "I'd hate to get too giddy yet since we have a couple of days to go. But if the rest of the mission goes as well as it already has, we'll have 100 percent success and we'll be leaving a perfect space station behind. Everything we've changed out so far has been performing beautifully. This battery 2 early discharge is our first real unusual signature, and it's still too early for us to decide we have a real problem in that slot. This could just be a problem with the initial startup. So I'm very happy with what we've seen so far." 07:45 a.m. Update: Battery issue resolved After a bit of troubleshooting, Russian engineers were able to resolve an apparent problem with one of the international space station's new batteries (see the 3:15 a.m. entry below for details). The Atlantis astronauts are replacing four of the station's six batteries: Nos. 1, 2, 3 and 5. Batteries 1 and 2 were installed overnight Monday and battery 3 was installed early today. It takes some 20 hours to fully charge a new battery and the batteries must be charged up one at a time. With battery 1 fully charged and on line, battery 2 was being charged when the astronauts replaced battery 3 early today. Battery 2 suddenly began discharging after about two hours, raising the possibility of a problem. Russian flight controllers disconnected the powerpack while they investigated the issue. As it turns out, the process of replacing a battery - in this case, battery 3 - can cause a battery being charged up to begin discharging. Russian engineers apparently did not realize this before the astronauts began repairing the electrical system aboard the Russian Zarya module. There is no problem with battery 2 and it currently is being charged normally. To prevent this problem from occurring again, flight controllers will not begin charging battery 3 until battery 5's replacement is complete early Thursday. All four new batteries should be fully charged before Atlantis departs Friday evening. 06:30 p.m. Update: Astronauts install fourth battery; new undocking time approved The Atlantis astronauts hit the deck running after a 4:26 p.m. wakeup call today, working to replace a fourth and final battery aboard the Russian Zarya module of the international space station. Four of six space station batteries are being replaced because of degraded performance. The first two, batteries 1 and 2, are fully charged and on line. Battery 3 will be charged after installation of battery 5, currently underway, is complete. Battery 5 will be recharged after battery 3. Commander James Halsell and pilot Scott Horowitz plan to carry out another hour-long reboost maneuver this evening starting at 9:16 p.m., pulsing Atlantis's steering jets for one hour to boost the space station seven to nine miles higher. During the first such reboost operation Tuesday night, the station's altitude was increased more than nine miles. A third reboost maneuver is planned tomorrow night. U.S. and Russian flight controllers hope to increase the station's altitude by about 27 miles when all is said and done without using any of Zarya's limited on-board fuel supplies. NASA's mission management team today approved a plan to delay Atlantis's undocking from the station by one orbit to improve communications coverage over Russian ground stations. Undocking now is targeted for 7:07 p.m. Friday. Updated timelines will be posted below as soon as possible. 10:30 p.m. Update: Second station reboost maneuver complete Atlantis skipper James Halsell and pilot Scott Horowitz fired the shuttle's small steering jets 27 times over a period of 56 minutes and 30 seconds this evening in the second of three maneuvers to boost the international space station's altitude by about 27 statute miles. During the first such maneuver Tuesday, the station was boosted 9.7 miles. This time around, the lab's orbit was raised an average of 9.25 miles, giving the station an apogee, or high point, of 225.9 miles and a low point, or perigee, of 223.7 miles. A third and final reboost maneuver is scheduled Thursday evening. Earlier this evening, the astronauts installed a fourth battery in the Russian Zarya module to complete the highest priority of the 98th shuttle mission. Four of the module's six batteries have now been replaced, along with four charge-discharge units and a computer controller to restore the module's ailing electrical system to health. Later this evening, the crew will replace a radio telemetry unit in Zarya that has reached the end of its design life and transfer four bags of water generated by the shuttle's electricity producing fuel cells. The fuel cells combine liquid oxygen and hydrogen in a sort of reverse hydrolysis to produce electricity. The by-product is fresh water, much of which is dumped overboard during a typical shuttle mission. But for station assembly flights, the excess water is transferred to holding tanks on the station for use by future crews. For viewers with access to NASA television, here are this evening's live downlink windows: WINDOW OPENS...WINDOW CLOSES 11:14 p.m......11:47 p.m. 11:48 p.m......12:23 a.m. 01:00 a.m......01:30 a.m. 02:10 a.m......02:19 a.m. 02:42 a.m......03:37 a.m. 04:20 a.m......05:18 a.m. 06:01 a.m......07:00 a.m. 07:08 a.m......07:42 a.m. 07:43 a.m......08:39 a.m. The astronauts will field questions from reporters at 11:21 p.m. and a mission status briefing is on tap, as usual, at 2:30 a.m. This status report will be updated as warranted. =================================================================== Astronauts wrap up repair work (05/25/00) 03:30 a.m. Update: Engineers troubleshoot battery problem Russian engineers are troubleshooting another possible problem with one of the new batteries installed aboard the Russian Zarya module of the international space station. NASA managers are hopeful the problem can be resolved, although the Atlantis astronauts may have to do a bit of unscheduled repair work later today, before the station is sealed off prior to undocking Friday evening. Four of Zarya's six batteries - Nos. 1, 2, 3 and 5 - have been replaced, along with chargers known by their Russian acronym, PTAB (pronounced pah-TAHB). Batteries 1 and 2 are fully charged and on line while battery 3 is in the process of being charged up. Battery 5, the fourth replacement, will be charged later today. "We've completed all the equipment changeouts," said space station flight director Paul Hill. "Most of the new equipment we've installed has already been checked out and is looking nominal. Tonight, we have five active batteries for the first time in six months and by tomorrow, we'll have six active batteries on the main bus and be back up to full strength." But Hill said engineers have seen "an anomalous signature" on battery 3. It is possible one of the wires running between the battery and its PTAB is not fully seated or that a pin in one of the connectors is bent and not making good contact. "Moscow will be looking at that overnight while we continue charging," Hill said. "The problem that we have doesn't keep us from charging the battery. It does, however, cause some unstable current fluctuations in the other batteries when we put that battery into normal operation." Depending on what the Russian battery experts determine, "it's likely we'll send (the astronauts) back under the floor (of the Zarya module) to check those connections to the PTAB and to the battery in slot 3," HIll said. "And depending on what we see, we have some options to take some of the equipment we've changed out and put it back into slot 3 like we talked about yesterday when we were looking at battery 2." Battery 2 began discharging unexpectedly two hours after engineers began charging it up. It later was determined that disconnecting battery 3 prior to its replacement affected the charging cycle of battery 2. The battery was, in fact, healthy and it is now fully charged and on line. Before the issue had been resolved, however, Hill said if worse came to worse, battery 2 could be replaced with the battery taken out of slot five. And that again is an option for battery 3. If the power pack turns out to be defective, the astronauts likely will be told to replace it with the original battery 5. Hill said in a previous briefing that engineers are not even sure there's anything wrong with the original battery 5 and that it was being replaced just to play it safe. "We're still kind of early in looking at the telemetry and trying to assess what the problem is and by this time tomorrow, we could have gotten back under the floor and reseated these connectors and battery 3 could, in fact, be looking normal," Hill said. "We'll know a lot more about it tomorrow (later Thursday). Meanwhile, the battery is charging up fine and we'll still have it ready and fully charged up tomorrow morning when we start up on battery 5." All in all, he said, "I'm still very happy with all the new equipment and how it's performing. We're definitely getting what we came for with the lifetime extension and all the refurb equipment that's going into the spacecraft. So I'm very comfortable that when we leave on this flight we're still going to have a very robust spacecraft and we'll be very ready for service module docking in the two months." The service module is a critical Russian component scheduled for launch in July that will take over many of the power and propulsion chores currently provided by the Zarya module. The unmanned linkup will be accomplished primarily by remotely maneuvering Zarya to the service module for an automatic docking. "In the very worst case, if battery 3 is not usable at all, we're still one battery better off than we were one week ago," Hill said. "And we also know we can pull off a normal service module docking with four batteries and we know how to do it with three. So we're not standing on the edge of a cliff even without battery 3. But I'm very hopeful we'll come in tomorrow and battery 3 will be on line and looking normal." Susan Helms, an astronaut aboard Atlantis who will spend several months aboard the space station next year as part of its second full-time crew, said the Russian flight control team's experience operating the Mir space station has paid off when it comes to installing and checking out new equipment installed in the international station. "We have greatly benefitted from the Mir experience," she told a reporter in a question-and-answer session late last night. "A lot of the work we've done the last day or two has involved components - the batteries, memory units, cables and the like - things that have been on Mir for a long time and the Russians have a great deal of experience making these changeouts. So I'd say this bodes well for the future." 06:30 p.m. Update: Battery issue resolved; crew wraps up station work Russian engineers have given a suspect battery aboard the international space station a clean bill of health, clearing the way for the Atlantis astronauts to wrap up a few final repair tasks this evening before undocking Friday night. At 7:36 p.m., commander James Halsell and pilot Scott Horowitz will begin firing Atlantis's steering jets in a third and final set of maneuvers designed to boost the space station's altitude by an average of about 27 miles. During two earlier sessions, the station's average altitude was increased more than 18 miles. At 10:11 p.m., Halsell, Horowitz and Mary Ellen Weber will discuss the mission with CBS News in a live interview from the station. The astronauts are scheduled to leave the space station, sealing hatches behind them, around 2 a.m. A mission status briefing is on tap at 2:30 a.m. The primary goal of the 98th shuttle mission was replacing four of the six batteries in the Russian-built NASA-financed Zarya module: batteries 1, 2, 3 and 5. Earlier today, during charging of battery 3, engineers noticed unusual current fluctuations that raised questions about the power pack's health. But after investigating the matter in detail, Russian battery experts decided the unit was operating normally and that the fluctuations were an artifact of telemetry and remote commanding. This status report will be updated after this evening's CBS News interview and after the Friday morning status briefing. Or as warranted. 11:00 p.m. Update: Astronauts pleased with mission results Their maintenance work complete, the Atlantis astronauts are preparing to float out of the international space station for the last time later this evening, sealing hatches behind them and setting their sights on undocking Friday night. Before taking a break for lunch, commander James Halsell, pilot Scott Horowitz and Mary Ellen Weber discussed the mission with CBS News' "Up To The Minute," saying pre-flight reports of bad air quality and excessive background noise were a bit overblown. "It is true that on a previous mission, they had some problems with the air quality," Halsell said. "We have engineers at NASA and also in Russia who worked hand in hand to change the air ducting, to add personal ventilation fans, to carefully analyze and if necessary modify the entire air ventilation scheme when the shuttle is docked to the station to fix the problem. So the story here is that a problem was recognized and it was solved. "With regard to the noise, I can report to you we've had no noise problems at all on the station," he said. "The standards for noisiness are more strict for people who will be up here for long-term stays than it is for us who are only up here for a few days. So keeping the highest possible standard of safety, especially for the crews that will be living up here, they want to continue to work on the noise issue. We've done some of the fixing in that department already. We've added acoustic mufflers to some of the air ducts, which has noticeably dampened out some of the noise." As for the quality of life aboard the new space station, Halsell said if NASA ever offered him a chance to live aboard the outpost "I'd jump at that opportunity." Added Horowitz: "Living and working in space is a great pleasure and also a great honor. ... With this much volume, it would be a piece of cake to live up here compared to working in the cramped confines of the middeck of the space shuttle." Earlier this evening, the astronauts completed one of their major objectives, carrying out a third and final series of rocket firings to increase the space station's altitude using spare propellant aboard the shuttle. During the 54-minute procedure, Halsell and Horowitz fired Atlantis's steering jets 26 times to put the station in an orbit with an apogee, or high point, of 237.7 statute miles and a perigee, or low point, of 229.4 miles. When the shuttle docked with the space station early Sunday, the outpost had an apogee of 209 miles by 203 miles. As a result of three shuttle reboost maneuvers over the past three days, the station's orbit was raised an average of 27.6 miles, exactly what flight planners were hoping for. The flight plan calls for the crew to complete their exit of the station by 3:06 a.m. Undocking is scheduled for 7:07 p.m. Friday followed by a brief fly-around for photo documentation. Atlantis is scheduled to land at the Kennedy Space Center at 2:18 a.m. Monday. During five days of docked activity, the crew replaced four of the Russian Zarya module's six batteries, replaced four degraded charge-discharge units, installed a new battery controller and installed new smoke detectors and fans to improve air circulation. They also staged a spacewalk to mount a Russian crane on the station's hull and to replace a faulty antenna and transferred supplies and equipment that will be used by the first full-time crew later this year. The space station is one of the most complex - and expensive - engineering projects in history. But unlike the Apollo moon program of the 1960s, the station hasn't generated the same level of public support and enthusiasm. Weber said that was to be expected in a program designed to utilize space rather than explore it for the first time. "We're entering a whole new era in space travel," she said. "It's like now, when you get on an airplane, you don't have the same twinkle in your eye that I'm sure the Wright brothers had when they took their first flight. We're now using air travel as part of our daily lives, we're having productive lives as a result of it. That's what space travel is turning into, we're now not just going up for the thrill of it, for the challenge of it, but to make use of space. And certainly when we enter that stage, people's attitudes are going to change as well." Horowitz said earlier in the mission that Atlantis's approach to the space station reminded him of a scene in the movie "2001: A Space Odyssey" in which a futuristic shuttle docked with a much larger station. Asked tonight if he was disappointed NASA hasn't done more in the 30 years since the movie was released, Horowitz said the current station is impressive enough. "The space station in the movie was much larger," he agreed. "But I can tell you I'm awfully impressed with the amount of volume we have inside here and we're just in the infant stages of this space station. Do I have any regrets? I don't know that they'd be regrets, but I have a lot of hope that in the future, this will be just the first step and that maybe even though I didn't get a chance to go on to Mars and the other planets, that this will be a stepping stone for maybe my daughter and her generation to travel on to the other planets and out into the stars." Here are the remaining live television downlink windows for this evening and early Friday: WINDOW OPENS...WINDOW CLOSES 11:35 p.m......12:20 a.m. 12:21 a.m......12:54 a.m. 01:37 a.m......02:31 a.m. 03:35 a.m......04:11 a.m. 04:54 a.m......05:54 a.m. 06:27 a.m......06:57 a.m. 06:57 a.m......07:34 a.m. This status report will be updated after the overnight mission status briefing at 2:30 a.m. or as conditions warrant. =================================================================== Astronauts finish repairs; undock from space station (05/26/00) 03:10 a.m. Update: Astronauts leave space station Turning out the lights and dogging the hatches, the Atlantis astronauts methodically exited the international space station early today, leaving a healthy, refurbished spacecraft behind after a near-flawless repair mission. As of 3:05 a.m., the crew had closed three of five internal station hatches as they worked their way back toward the space shuttle. If all goes well, Atlantis will undock from the space station at 7:07 p.m. this evening, setting the stage for arrival of a new Russian command module in July. "I can't be happier with the way the mission has gone," flight director Phil Engelauf said during a 2:30 a.m. status briefing. "We're at more than 100 percent of the planned objectives accomplished, the crew is still in great spirits, everybody's doing good and everything's just been perfect so far. I couldn't be happier." Said space station flight director Paul Hill: "It is a good night for space station. Atlantis and her crew did wonders for us. They refurbed the vehicle and they'll be leaving a pristine ISS behind. All the equipment this crew installed for us is performing beautifully." Almost all. Two of the 10 new smoke detectors installed in the Russian Zarya module are giving false readings and have been shut down. Engineers suspect they are detecting dust or fibers kicked up by the astronauts during their repair work. The detectors will be turned back on later, after Atlantis departs and the air settles "down" a bit. Three of Zarya's four new batteries, meanwhile, are performing normally and the fourth will be brought on line later today after it finishes a 20-hour charging cycle. For the first time in months, the Russian module is equipped with six healthy batteries, giving flight managers confidence the station will remain healthy through the end of the year and certainly through arrival of the long-delayed service module in July. "All of our objectives have been completed, all of our get-ahead tasks for future flights have been completed," said Sharon Castle, launch package manager. "Our projection is we will have delivered over 3,300 pounds of cargo on this flight. ... I could not be any happier. This is just a great day." 03:40 p.m. Update: Crew poisede for undocking The Atlantis astronauts are gearing up to undock from the international space station this evening. Crew wakeup is on tap at 4:11 p.m. Here's a timeline of this evening's events (times in EDT and mission elapsed time): TIME.......DD...HH...MM...EVENT 05/26/00 04:11 PM...07...09...00...Crew wakeup 04:31 PM...07...10...20...Group B computer powerup 05:30 PM...07...11...19...Sunrise 05:59 PM...07...11...48...Noon 06:27 PM...07...12...16...Sunset 07:03 PM...07...12...52...Sunrise 07:03 PM...07...12...52...Undocking window opens 07:03 PM...07...12...52...Atlantis undocks from space station 07:08 PM...07...12...57...Range: 30 feet 07:12 PM...07...13...01...Undocking window closes 07:21 PM...07...13...10...Begin flyaround operation 07:21 PM...07...13...10...First -Rbar crossing 07:22 PM...07...13...11...Noon 07:33 PM...07...13...22...First -Vbar crossing 07:44 PM...07...13...33...First +Rbar crossing 07:44 PM...07...13...33...Separation burn 07:59 PM...07...13...48...Sunset 08:07 PM...07...13...56...Range: 1,640 feet 08:15 PM...07...14...04...Station motion control system activation 08:30 PM...07...14...19...Mission status briefing 08:35 PM...07...14...24...Sunrise 10:21 PM...07...16...10...Video replay of undocking on NASA TV 10:41 PM...07...16...30...Crew off duty time begins 05/27/00 12:11 AM...07...18...00...Crew meals begin 05:26 AM...07...23...15...Russian PAO event with Usachev 08:11 AM...08...02...00...Crew sleep begins 04:11 PM...08...10...00...Crew wakeup This status report will be updated as warranted. 10:16 a.m. Update: Landing time adjusted The shuttle Atlantis's undocking time time has moved up about three minutes, from 7:07 p.m. to 7:02:44 p.m. this evening. A final separation rocket firing is scheduled for 7:44 p.m. Atlantis's landing time also has been tweaked a bit by flight controllers at the Johnson Space Center in Houston. Deorbit ignition is now targeted for 1:16 a.m. Monday with landing at the Kened Space Center expected at 2:40 a.m. The updated times are included in the latest version of NASA's television schedule (rev. F) posted below. 07:05 p.m. Update: Shuttle Atlantis undocks from space station The shuttle Atlantis undocked from the international space station today, leaving the now-healthy orbital outpost behind after a successful mission to repair the lab's electrical system. With pilot Scott Horowitz at the controls, Atlantis separated from the space station at 7:03 p.m., pushed straight up with respect to Earth by powerful springs in the shuttle/station docking module. "Houston, we have sep," commander James Halsell reported as the spacecraft slowly separated. "We copy," replied mission control. After backing away about 450 feet, Horowitz plans to guide Atlantis through a half-loop around the station before departing the scene for good at 7:44 p.m. as the shuttle passes directly below. One orbit after separation - at 8:15 p.m. - Russian flight controllers plan to re-activate the station's motion control system, which then will take over the job of keeping the lab properly oriented. A videotape replay of undocking from cameras aboard Atlantis will be downlinked around 10:21 p.m. The shuttle's seven-member crew will enjoy a half-day off starting at 10:41 p.m. Atlantis docked with the station at 12:31 a.m. last Sunday and it's departure this evening ended a linkup lasting five days 18 hours and 32 minutes. During that period, the astronauts replaced four of the Russian Zarya module's six batteries, installed new battery control equipment, staged a spacewalk to install a Russian crane on the station's hull and to replace a faulty antenna and transferred more than 3,000 pounds of equipment and supplies to the unfinished lab complex. The astronauts also used the shuttle's maneuvering jets to increase the station's altitude by some 27 miles, setting the stage for arrival in July of a new Russian command module. This status report will be updated after a planned 8:30 p.m. mission status briefing at the Johnson Space Center in Houston. In the meantime, see the detailed timeline immediately below for additional details about this evening's departure from the space station. 10:00 p.m. Update: NASA manager pleased with mission success; warns of future problems NASA managers praised the Atlantis astronauts today for pulling off a complex overhaul to restore the international space station to good health. Even so, James van Laak, manager of space station integration and operations, took a moment to point out that not every station assembly mission will be as trouble free as this one, saying "it would be perhaps inaccurate or dishonest, even, to not make it clear that we are undertaking one of the greatest engineering challenges humankind has ever undertaken. "And I guarantee you over the next few years we will stumble and scrape our knees a few times and I wouldn't be human if I didn't admit to some concern about that," he said. "But we have great confidence we can do this safely, we're not going to hurt people and we don't believe we're going to do damage to the hardware. We're just going to occasionally stub our toes and have to take a step backward and address those problems." Atlantis undocked from the space station at 7:03 p.m. After looping around below the lab complex, pilot Scott Horowitz fired the shuttle's maneuvering jets to leave the station behine, setting the stage for a major milestone in July: Arrival of a new Russian command center called the service module. "This mission was so successful because the two vehicles performed so well and the teams the planned, designed and trained and then executed the mission performed so well," said Jeff Bantle, a mission operations representative at the Johnson Space Center. "We really gave the space station a major overhaul. We replaced more than half of the battery storage capability. All six battery sets are working very well and I think the ISS is ready for what I consider a very key event, this rendezvous with the next module. That's going to be probably the most important thing the (Russian Zarya module) needs to do. So I think we put it in great shape for that." The service module, which will take over propulsion chores from Zarya while providing crew quarters and additional electrical power, is scheduled for launch atop a Proton rocket around July 12. Once in space, the service module will serve as a target for the Zarya module, which will carry out a remotely controlled rendezvous and docking using a Russian-built guidance system. Over the next few days, Russian flight controllers plan to put the docking system through a series of tests to verify its readiness for the main event. The system has generated suspect data on one channel in recent weeks and engineers want to make sure they fully understand its performance before the service module's launch. "We're wrapping up the docked portion of an absolutely outstanding mission," van Laak said. "All of our mission objectives have been accommplished, we've left the space station in fantastic mechanical condition, ready to proceed to the docking of the service module in July. All the maintenance items have been done, the air quality problems we might have had on the last mission have been absolutely corrected and there are no concerns whatever about this crew or any other crew visiting the station. Basically we're ready to go and very, very pleased." =================================================================== Astronauts gear up for entry tests (05/27/00) The Atlantis astronauts are packing up loose gear and preparing to test the shuttle's re-entry systems this evening before gliding back to Earth early Monday to close out a successful space station repair mission. Commander James Halsell and pilot Scott Horowitz plan to fire up one of Atlantis's three hydraulic power units, called APUs, shortly after 8 p.m. as part of a routine pre-entry instrumentation checkout and steering test. About an hour after that, Atlantis's smaller maneuvering jets will be hot fired to make sure they'll be ready for use if needed. All seven astronauts plan to participate in a crew news conference at 11:41 p.m. The event will be carried live on NASA television. Here's a timeline of activity through the end of the mission (in EDT and mission elapsed time): TIME.......DD...HH...MM...EVENT 05/27/00 07:11 PM...08...13...00...Cabin, Spacehab stow begins 08:11 PM...08...14...00...Flight control system checkout 09:21 PM...08...15...10...Reaction control system hotfire 11:11 PM...08...17...00...Crew photo 11:41 PM...08...17...30...Crew news conference on NASA television 05/28/00 12:11 AM...08...18...00...Deorbit briefing and review 12:41 AM...08...18...30...PILOT landing practice 02:30 AM...08...20...19...Mission status briefing on NASA television 04:36 AM...08...22...25...KU-band antenna stow 04:41 AM...08...22...30...Ergometer stow 08:11 AM...09...02...00...Crew sleep begins 04:11 PM...09...10...00...Crew wakeup 07:06 PM...09...12...55...Group B computer powerup 07:21 PM...09...13...10...Inertial measurement unit alignment 08:11 PM...09...14...00...Crew meal 09:16 PM...09...15...05...Deorbit timeline begins 10:36 PM...09...16...25...Payload bay door closing 05/29/00 01:16 AM...09...19...05...Deorbit ignition 02:40 AM...09...20...09...Landing This status report will be updated after the crew news conference at 11:41 p.m. =================================================================== Astronauts pack up for re-entry; weather 'iffy' (05/28/00) 01:15 a.m. Update: Astronauts ready for long-term stays Susan Helms can't wait to begin a long-term stay aboard the international space station. Helms and two of her Atlantis crewmates - James Voss and cosmonaut Yury Usachev - are scheduled to spend four to six months aboard the outpost next year as its second full-time crew. After spending a week working in the unfinished station, Helms said she'll have no problem settling in for a long-duration expedition. "What we saw up here in the last couple of days is less than half the volume we're going to have," she said during a news conference from Atlantis late Saturday. "Right now, we've only got (two modules in orbit). By the time we return, we'll have the Russian service module ... and we'll also have the U.S. laboratory. "When you add those two other modules on to it, it'll more than double in length," she said. "Just as an experiment, Yury and I decided to count the seconds going from one end of the space station to the other. And it took 38 seconds to translate from one end to another, which is actually quite long. So we're going to basically more than double that length and when you think about three people living on orbit for three months, there is plenty of room. We're going to have plenty of space to live and I don't think it'll seemed cramped at all. It'll probably be just the opposite, we'll have trouble finding each other." For his part, Voss said he was "amazed" at the roominess of the U.S. node module. "We floated inside and you could float in the middle without touching anything," he said. "And also, just how clean and nice everything looked in the node and in the FGB (Russian Zarya module). We were really impressed with how spanking clean everything was. I think it's a place, after being here for about a week, that I'll be able to live for five-and-a-half months." Added Helms: "It felt like home. It was just beautiful, I was very, very impressed." 04:00 a.m. Update: Weather 'iffy' for Monday landing With stormy weather moving toward the Kennedy Space Center, the Atlantis astronauts are aiming for a landing Monday morning at 2:20:11 a.m. to close out a near-flawless space station repair mission. With a marginal forecast but plenty of fuel and supplies, the astronauts will attempt to land in Florida Monday or Tuesday before NASA starts staffing Edwards Air Force Base, Calif., for possible landing attempts Wednesday and Thursday. "The weather (Monday) is somewhat iffy," said entry flight director John Shannon. "There is a front tied to a low pressure system, it'll be off the East Coast, and that front extends down through Georgia and the Florida panhandle area. And it really depends on how close it gets to the Cape. "It'll be pushing rain storms in front of it and some higher winds," he said. "We have a limit on the rain showers, they can be no closer than 30 nautical miles to the shuttle landing facility. ... There's also a 12-knot (crosswind) limit. Right now, the crosswinds are predicted at 12 knots, so we're hoping that prediction is not exceeded." Commander James Halsell and his crewmates will have two landing opportunities Monday on successive orbits and two more opportunities Tuesday. Shannon said forecasters believe Atlantis's best shot is to get down on the first opportunity Monday "because we're going to be trying to beat that front and all the rain clouds that will be pushed ahead of that front." The forecast for Tuesday is not much better. The front should be just past the Kennedy Space Center and, if the models hold up, there will be an even better chance for rain showers in the area. But Shannon said "it's really too early to call that one." Atlantis has enough air, water, food and fuel to stay in orbit until Thursday, if worse came to worse, what Shannon called the "gotta come home day." With that much margin in consumables, NASA managers Saturday ruled out a landing at Edwards Air Force Base in California's Mojave Desert before Wednesday at the earliest. "We have two opportunities to the Kennedy Space Center and Edwards for the next four days - Monday, Tuesday, Wednesday and Thursday," Shannon said. "The mission management team this morning (Saturday) decided that since we have all those consumables, we will attempt the Kennedy Space Center both Monday and Tuesday. We would have two orbits on each of those days. If we were not able to come home because of weather on Monday or Tuesday we would bring up Edwards for Wednesday and-or Thursday opportunities." Here are all the deorbit and landing opportunities for Monday through Wednesday: DATE....ORBIT...DEORBIT BURN...LANDING....SITE 05/29...155.....01:13 AM.......02:20 AM...Kennedy Space Center 156.....02:50 AM.......03:58 AM...KSC 05/30...170.....12:09 AM.......01:16 AM...KSC 171.....01:45 AM.......02:51 AM...KSC 05/31...186.....12:43 AM.......01:47 AM...KSC 187.....02:14 AM.......03:18 AM...Edwards Air Force Base 187.....02:20 AM.......03:23 AM...KSC 188.....03:50 AM.......04:53 AM...Edwards Air Force Base The deorbit rocket firing will reduce Atlantis's velocity by about 314 feet per second - 214 mph - just enough to set up a landing in Florida. Earlier in the mission, engineers noticed a possible problem with a propellant valve in the shuttle's left-side orbital maneuvering system rocket pod. Shannon said today engineers now believe the valve is working normally and that a transducer that indicates the valve's position has malfunctioned. If they are wrong and it's the valve, not the transducer, that's at fault, the engine will still fire. The worst-case failure scenario, Shannon said, is that the crew could have to manually shut the engine down. No one expects that to happen and even if it did, Shannon said it would have no impact on re-entry and landing. "We'll just use our normal procedures," Halsell said during a news conference late Saturday. "There's a small outside chance that we need to protect against that the engine valve would not close when it was supposed to, but we have backup procedures that would allow us to shut down the engine." Otherwise, Halsell said he's looking forward to his first night landing. "I've been practicing for this for the last 10 years and I've had the opportunity to land on a couple of previous occasions," he said. "This will be my first night landing and more than being concerned about it, I'm excited about the opportunity to expand my ... experience with regard to space shuttle operations. Before taking off, before launch, we did nothing for the previous couple of weeks but night approaches and night practice landings. So I'm looking forward to it. It's going to be just another of the great parts of this adventure." And what if the crew is forced to spend Memorial Day in orbit? "We do happen to have barbecue on board that we have not yet eaten," joked astronaut Susan Helms. "Yes, we'll be able to celebrate the holiday in style!" 06:45 p.m. Update: Astronauts finish packing for Monday morning landing The Atlantis astronauts are readying the shuttle for return to Earth this evening and a landing at 1:20 a.m. at the Kennedy Space Center. There are no technical problems with the shuttle and the only question mark is the weather. Forecasters are calling for generally acceptable conditions, although high winds and rain showers ahead of an approaching frontal system could cause problems (see the 4 a.m. CBS News status report immediately below for complete details). 11:30 p.m. Update: Weather down to the wire for landing The Atlantis astronauts have closed the shuttle's 60-foot-long cargo bay doors and loaded re-entry software into the ship's flight computers in hopes of making an on-time 2:20 a.m. landing at the Kennedy Space Center to close out a successful space station repair mission. The only concern is the weather, with slightly high crosswinds from an approaching frontal system expected that could cause problems. Crosswinds currently are right at NASA's 12-knot limit For daylight landings, NASA flight rules allow crosswinds as high as 15 knots. Based on recommendations from an astronaut flying approaches in a jet rigged to handle like a shuttle on final approach, the limit can be increased slightly. But for night landings, crosswinds are limited to 12 knots or less. And entry flight director John Shannon said early Sunday he will not violate that limit this evening. "The highest crosswind we've ever landed in has been 11 knots and that was fairly recently and that was a daytime landing," he said. "So to commit to a night landing at greater than what our current flight experience is, to me would not be a very smart thing to do and I expect to fully follow the rules. If it's not a good day, we're not going to land." Here's the remainder of the crew's deorbit timeline for Monday morning's planned re-entry and touchdown: TIME TO....EDT...........EVENT DEORBIT BURN TIG-1:40...11:33:00 PM...Crew entry review TIG-1:25...11:48:00 PM...Commander, pilot configure pressure suits TIG-1:00...12:13:00 AM...Commander, pilot strap in; MS's don suits TIG-0:43...12:30:00 AM...Braking engine steering test TIG-0:40...12:33:00 AM...Hydraulic power units set for start TIG-0:33...12:40:00 AM...Toilet deactivation complete TIG-0:25...12:48:00 AM...Payload bay vent doors set for entry TIG-0:20...12:53:00 AM...Mission control 'go' for deorbit burn TIG-0:14...12:59:00 AM...Crew seat ingress complete MONDAY TIG-0:05...01:08:00 AM...First hydraulic power unit started 01:12:00 AM...Deorbit ignition 02:20:11 AM...Landing Atlantis's crew has two opportunities on successive 91-minute orbits to land Monday. If they don't make it, they'll remain in orbit an extra day and try again on Tuesday. If they still don't make it - and the weather is expected to worsen - NASA will begin staffing Edwards Air Force Base, Calif., on Wednesday. Atlantis must be on the ground by Thursday at the latest. Here are this evening's landing opportunities: DATE....ORBIT...DEORBIT BURN...LANDING....SITE 05/29...155.....01:13 AM.......02:20 AM...Kennedy Space Center 156.....02:50 AM.......03:58 AM...KSC Landing times through Wednesday are posted below in the 4 a.m. CBS News update. =================================================================== Atlantis glides to smooth nighttime landing (05/29/00) 12:50 a.m. Update: Atlantis given 'go' for deorbit burn With calmer winds over the Kennedy Space Center, entry flight director John Shannon has given the Atlantis astronauts a "go" to proceed with deorbit ignition at 1:12 a.m., setting up a touchdown on runway 15 at 2:20 a.m. Crosswinds have died down with peaks of just 10 knots - two knots below NASA's nighttime limit - and with no other issues under discussion, Shannon cleared the astronauts to head for home. The deorbit burn will last three minutes and five seconds, changing Atlantis's velocity by about 213 mph. 01:15 a.m. Update: Deorbit burn complete The shuttle Atlantis's twin braking rockets ignited at 1:12 a.m. and burned for three minutes and five seconds to slow the ship by 213 mph, setting up a touchdown on runway 15 at the Kennedy Space Center at 2:20 a.m. The deorbit rocket firing, carried out over the equator southeast of India, went smoothly and there were no apparent problems with a suspect propellant valve in the left-side orbital maneuvering system pod. "We're on our way home," commander James Halsell said when the burn was complete. This status report will be updated after Atlantis lands or as conditions warrant. 02:45 a.m./03:30 a.m. Update: Atlantis glides to picture-perfect touchdown The shuttle Atlantis glided to a smooth nighttime landing early today, touching down on runway 15 at the Kennedy Space Center to close out a near-flawless space station repair mission. With veteran commander James Halsell and pilot Scott Horowitz at the controls, the black-and-white spaceplane dropped out of darkness and into the glare of runway spotlights a few seconds before touching down at 2:20:17 a.m. "Wheels stopped, Houston," Halsell radioed after Atlantis coasted to a halt. "Roger wheels stopped, Atlantis. Jim, congratulations to you and the crew on just a super mission to the international space station," replied astronaut Rick Sturckow from mission control. "Smiles around the cabin here, appreciate your help," Halsell called. It was the fourteenth night landing in shuttle history, the ninth at the Kennedy Space Center. Mission duration was nine days 20 hours nine minutes and eight seconds. "I've been in this business of human spaceflight for over 20 years and it never ceases to amaze me how wonderful a machine the space shuttle really is," said shuttle program manager Ron Dittemore. "We had a wonderful mission, everything worked just right and the ground teams, process teams, mission control teams and the flight crew made everything look easy. And believe me, it takes a lot of work ... to do the job you have seen over the past 10 days. These crews did a wonderful job and we had a very successful mission." The international space station, meanwhile, sails on in orbit after a complex orbital overhaul. During six days docked to the outpost, Atlantis's crew replaced four of the Zarya module's six batteries; installed new battery control equipment; replaced a faulty radio antenna on the U.S. Unity module; installed a replacement telemetry unit in Zarya; and transferred 1.5 tons of supplies and equipment to the station that will be used by the lab's first full time crew after arrival late this year. They also installed 10 new smoke detectors, new fans to improve air circulation, fresh water for the next crew and a computer cable that will enable flight controllers in Moscow to activate critical Zarya systems through NASA's communications link. Flight controllers say the station's systems are operating flawlessly and that all systems are go for arrival in July of a new Russian command module that will take over many of Zarya's functions. Thanks to repairs by Atlantis's crew, Zarya's systems are now healthy and more than up to the task of docking with the passive command, or service, module. Once the service module is attached, station assembly will pick up this fall with a quick succession of shuttle assembly flights and arrival of the first full-time crew in early November. "Once we get into the fall, it's off to the races," Dittemore said. Three of Atlantis's crew members will be following station developments with more interest than most. Cosmonaut Yury Usachev, Susan Helms and James Voss plan to spend four to six months aboard the space station next year as the lab's second full-time crew. All three appear eager to return to the unfinished complex. "It felt like home," Helms said late Saturday. "It was just beautiful, I was very, very impressed." Helms, Usachev, Voss, Halsell, Horowitz, Mary Ellen Weber and Jeffrey Williams were out of Atlantis about an hour after touchdown. All seven will spend Memorial Day at the Kennedy Space Center before flying back to Houston early Tuesday. "Thanks for coming out," Halsell said to well wishers and technicians on the runway. "I know it's bad hours for the arrival but we are certainly glad to be back home, we were glad to have had a successful mission, we're glad to be part of the beginning stages of the international space station and we just feel priviledged to have been a part of it all. Halsell then thanked his crewmates for the "outstanding work they did and I'd like to say thank you to the outstanding ops team back at the Johnson Space Center who were with us every step of the way. And finally and most importantly, I'd like to say thank you to the Kennedy Space Center. This vehicle hasn't flown for a couple of years and yet it flew in an outstanding fashion with no significant problems and it just served us so very well. "Thanks a lot for coming out tonight," Halsell concluded. "We're going to go have a shower, have a home-cooked meal and good night. Thanks a lot!" ===================================================================