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| Three Space Walks Will Add Sophisticated Laboratory |
| Overview |
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Astronauts Tom Jones and Robert Curbeam will perfrom three spacewalks to continue assembly of the International Space Station while Atlantis is docked to the station during Shuttle mission STS-98. During the spacewalks, Jones will be identifiable by red stripes around the legs of his spacesuit while Curbeam's suit will be pure white. Astronaut Marsha Ivins will operate Atlantis' robotic arm from within the shuttle cabin during all of the spacewalks, and Pilot Mark Polansky will serve as the intravehicular crewmember, assisting with the choreography of the spacewalks from inside the cabin. As they are scheduled, the third spacewalk on STS-98 will be the 100th spacewalk conducted by United States astronauts. Flight Day Four: First Space Walk The first space walk, planned to last about six hours and fifteen minutes, will be conducted on the fourth day of the mission, the day after Atlantis docks to the station. The overall objective is to mechanically attach the Destiny laboratory to the station and then connect electrical, computer and cooling lines between the lab module and station. The space walk is planned to prepare the laboratory to be entered by both the shuttle and station crews for the first time on the following day to begin its activation. Shortly before Jones and Curbeam begin the spacewalk, astronaut Marsha Ivins will latch Atlantis' robotic arm onto a capture fixture on one of the station's cone-shaped shuttle docking ports, called Pressurized Mating Adapter 2 (PMA-2), which occupies the berthing mechanism to which the Destiny lab must be attached. Before the spacewalkers leave the airlock, the shuttle crew will send commands to release the bolts holding PMA-2 to the station, and Ivins will move it from its berth, clearing the way for attaching Destiny to that berthing mechanism on the station's Unity connecting module. Jones and Curbeam will begin the space walk working in separate locations. Curbeam's first task will be to disconnect umbilicals between Atlantis and Destiny that had powered heaters on the module while in the shuttle payload bay. Next, he will remove covers, in place to prevent contamination during launch, from the Destiny lab's berthing mechanism at the aft end of Atlantis' payload bay. Meanwhile, Jones will climb up the station to the first truss segment, called the Z-1 Truss, almost 40 feet above Atlantis' cargo bay. On the Z-1 Truss, Jones will guide Ivins' work with the robotic arm, providing verbal cues to assist in aligning PMA-2 with a temporary storage location on the truss. Once properly aligned, Jones then will manually latch PMA-2 in place to the truss, temporarily out of the way of ongoing activities to attach the Destiny lab. Next, as Ivins latches the arm onto Destiny, lifts it from the shuttle cargo bay and rotates it into position to be attached to the station, the two spacewalkers will work farther up the station truss to prepare the station's starboard early cooling system radiator to be outstretched later in the mission. Then, they will release gimbal locks on a station communications antenna in preparation for the later activation of that system. When Ivins maneuvers Destiny to its berthing port on Unity and the crew sends commands for the berthing system to bolt together, Jones and Curbeam will stand by to assist if needed. Once Destiny is securely attached to the station, Jones and Curbeam will begin connecting electrical, data and cooling lines between the new module and the rest of the station. Flight Day Six: Second Space Walk During the second space walk, also planned to last about six hours and fifteen minutes, the PMA-2 shuttle docking port will be relocated from the temporary position on the station truss where it was placed during the first spacewalk to a permanent location at the forward end of the Destiny lab. Jones and Curbeam also will attach various equipment and fixtures to the exterior of the new module. After Ivins has latched Atlantis robotic arm onto PMA-2, Jones will manually loosen the latch that holds it to the temporary stowage location on the station. While Jones is working at the point on the station truss, Curbeam's first task will be to remove covers from the berthing mechanism at the forward end of the lab. Once Jones has released the temporary latch, Ivins will maneuver PMA-2 to the lab's forward berthing mechanism and attach it there, where it will serve as the primary shuttle docking location for most missions to come. Next, Jones will install thermal covers on the Destiny's four trunnions, the pins which held the module in the shuttle cargo bay during launch, and attach the exterior portion of a vent that will be used by the station's life support systems. Curbeam will install a slidewire along the length of the lab's exterior that will be used to ease the tether work required by future spacewalkers as they move up and down the length of the lab. Curbeam also will install several foot platform mounts and handrails. Jones will install a non-propulsive vent to Destiny’s Pressure Control Assembly (PCA), part of its environmental control and life support system. The next major task for both spacewalkers will be to install the future connection point for the station's robotic arm to Destiny’s exterior, preparing for the launch of that arm on shuttle mission STS-100 later in 2001. Ivins will maneuver the robotic arm into position for Jones to install a foot platform at its end in preparation for his work with the arm connection point, called a Power and Data Grapple Fixture (PDGF). Then, working from the arm foot platform, Jones will release the PDGF from its launch location in Atlantis' cargo bay and carry it to the position where it will be attached to Destiny. Meanwhile, Curbeam will be working at the attachment location on Destiny, removing two portions of the modules debris shielding to prepare to make electrical and computer connections for the PDGF. Jones will then install the fixture and both spacewalkers will replace the lab debris shields. Flight Day Eight: Third Space Walk The third space walk, planned to last a little over five hours, will attach a spare S-band communications antenna and equipment, called the S-Band Antenna Support Assembly (SASA), to the station; install an exterior shutter on the Destiny lab window; and connect electrical and data lines between the PMA-2 shuttle docking port and Destiny. At the end of the space walk, Jones and Curbeam also plan to conduct a test of the ability of the Simplified Aid for Extravehicular Activity Rescue (SAFER) jet backpack to maneuver two crewmembers. The SAFER jet packs are attached to spacewalker's spacesuits at all times as a type of "space lifejacket," to allow an astronaut to fly back to the station under his own power in the event he were to become untethered. The first task on the third space walk will be to remove the spare SASA from Atlantis’ cargo bay and attach it to a stowage location on the exterior of the station's lower truss segment, the Z-1 Truss. For that task, Curbeam will be in a foot platform at the end of the shuttle's robotic arm and Jones will assist from the station and shuttle exterior. Next, the two spacewalkers will work together to install an outside shutter on the Destiny lab window. The two spacewalkers will install the shutter and its associated gearbox and then remove a soft cover of insulation that protected the window during launch. They then will attach electrical and data connections between the PMA-2 shuttle docking port and the Destiny module. The connections will allow shuttle power and commands to reach the station on future missions, when PMA-2 becomes the primary shuttle docking location. The 30-minute SAFER test is planned as the last activity for the spacewalkers before they re-enter the shuttle cabin. |
Editorial/Technical Comments: ShuttlePresskit
EVA Timeline for Three Space Walks Will Add Sophisticated Laboratory
Time
Event
2/16:20
EVA 1 Airlock Egress
2/16:25
EVA 1 Sortie Setup
2/16:40
EVA 1 Secure PMA2 to Z1 Truss
2/16:40
EVA 1 Disconnect Lab Heater Umbilicals
2/17:05
EVA 1 Remove PCBM Cover
2/17:15
EVA 1 Release Starboard Radiator Cinch
2/17:35
EVA 1 Unbearth Lab
2/17:50
EVA 1 Release Starboard Radiator Winch
2/17:55
EVA 1 Release Space to Ground Antenna Gimbal Locks
2/18:05
EVA 1 Lab Pre-Install
2/18:40
EVA 1 EZ Setup Tasks
2/19:45
EVA 1 Connect LTA P612 Umbilical
2/19:45
EVA 1 Connect Z1/Lab NH3 Umbilical
2/20:30
EVA 1 Starboard Connectors CIDS 1
2/20:30
EVA 1 Port Connectors CIDS 1
2/21:25
EVA 1 Starboard Connectors CIDS 2
2:21:25
EVA 1 Port Connectors CIDS 2
2/21:55
EVA 1 Sortie Cleanup
2/22:15
EVA 1 Airlock Ingress
4/16:45
EVA 2 Airlock Egress
4/16:45
EVA 2 Release PMA 2
4/16:45
EVA 2 Remove Lab Thermal Cover
4/17:15
EVA 2 Sortie Setup
4/17:35
EVA 2 Install Trunnion Covers
4/17:35
EVA 2 Install Slidewire
4/18:30
EVA 2 Install Pressure Control Assembly (PCA) Vent
4/19:45
EVA 2 Install Payload Data Grapple Fixture (PDGF)
4/21:45
EVA 2 Install MMOD
4/22:15
EVA 2 Sortie Cleanup
4/22:40
EVA 2 Airlock Ingress
6/16:20
EVA 3 Airlock Egress
6/16:25
EVA 3 Transfer S-Band Antenna Support Assembly (SASA)
6/16:25
EVA 3 Sortie Setup
6/17:40
EVA 3 Install Shutter and Gearbox
6/18:10
EVA 3 Attach PMA 2 toLab Umbilicals
6/19:50
EVA 3 Sortie Cleanup
6/20:40
EVA 3 Incapacited Crew Demonstration
6/21:10
EVA 3 Airlock Ingress
