EVA 1
After Endeavour docks to the International Space Station, Marc Garneau will use the Shuttle’s robot arm to lift the P6 structure out of the payload bay where it will remain attached overnight. Prior to the start of the first space walk, he will use the arm to move the 35,000 pound assembly to the “low hover” position adjacent to Endeavour’s payload bay.
Once the P6 is in its low hover position, the EVA crew will exit Endeavour’s air lock and begin assembling the tools and hardware they will use during the planned 6 ˝ hour space walk.
EV1 Joe Tanner and EV2 Carlos Noriega will take positions on the forward and aft sides of the Z1 truss, respectively, to provide robot arm operator Marc Garneau with visual cues as he unberths the P6 structure. Garneau’s primary cues will come from the Space Vision System that provides him with a closed circuit television view of targets located on the P6 and the ISS, but Tanner and Noriega will provide verbal confirmation and additional visual cues throughout the unberthing process.
Once Garneau moves the P6 within its capture envelope, Tanner and Noriega will verify the ready-to-latch position and activate the capture latches on the Z1 truss, initiating a coarse alignment between the P6 and Z1 truss. Noriega will then drive the capture latch assembly to bring the P6 into fine alignment. After the structure is secured in place – by 127 turns of the Capture Latch Assembly (CLA) – Tanner and Noriega will begin securing bolts on each of the four corners of the P6 before releasing the capture latch to allow loads to be carried through the primary bolts.
At that point, Garneau will release the robot arm’s grip on the P6 structure and maneuver it into position to allow Noriega to attach an articulating portable foot restraint. At this point in the space walk, Pilot Mike Bloomfield assumes responsibility for operating the robot arm using it to maneuver Noriega as he connects the nine power, command and data umbilicals from Z1 to the forward face of the P6 that will provide power to the Orbital Replacement Units in anticipation of the deployment of the large solar arrays. Garneau, the back-up EVA crew member, then turns his full attention to acting as the on-board choreographer for the remainder of EVA 1 and all of EVA 2.
As Noriega connects the umbilicals, Tanner sets to work releasing first the starboard and then the port Solar Array Blanket Boxes (SABB) by releasing a series of 5/8” bolts – two on the nadir and six on the zenith ends of each SABB.
Noriega’s next task is to release the starboard Solar Array Wing (SAW) Beta Gimbal launch restraint (BGA) by releasing a pair of retention bolts and allowing the BGA to swing outward and upward or downward into its deployed position. Following the release of the starboard SAW BGA, Tanner will perform a similar function on the port side of the structure.
Both Tanner and Noriega then begin deploying the SABBs by releasing a pip pin on the mast canister and then rotating the boxes 90 degrees from their launch position to their deployable position. Once in the deploy position, a locking arm holds each box in position. The space walkers then release three bolts that hold the mast tip fitting releasing it from the top of the mast canister. At that point, Jett commands the mast to deploy, beginning the unfolding of the large solar arrays.
Noriega’s final scheduled EVA task is to remove six “cinches” around the PV Radiator that hold it in its launch configuration by releasing two winch bar mechanisms and pip pins – one at each end of the radiator.
Noriega and Tanner will then clean up the payload bay and head back in to Endeavour’s airlock concluding the first of two scheduled space walks.
EVA 2
The second space walk, scheduled for Flight Day 6, is designed to reconfigure electrical connections so that power from the newly-installed P6 solar arrays can be distributed to the U.S. elements of the ISS.
Noriega will work on the port side of the truss structure reconfiguring cables and moving them from one connector to the other to support the transfer of power and then removing a thermal shroud from a DC to DC Conversion Unit (DDCU). Tanner will remove a similar shroud from a baseband signal processor (BSP) and prepare to relocate the S-Band Antenna Subassembly (SASA) from its location on the Z1 truss where it was temporarily stowed by the STS-92 crew in October.
The thermal shrouds are removed to allow the DDCU and BSP to dissipate heat as they begin operating off of power generated by the P6 arrays.
One of the major elements of this second EVA is the relocation of the SASA as Tanner and Noriega move it from a temporary stowage location on the starboard side of the Z1 truss to its new location on the top of the P6 array. Tanner will remove the power connections that provide maintenance power to the Z1 truss as he unbolts the SASA. Mike Bloomfield will maneuver the arm to Noriega’s location tethered to the Integrated Equipment Assembly (IEA) where, in a series of “leap frog” like exchanges, Tanner and Noriega will alternate possession of the SASA until the antenna assembly is installed in its operating position on the IEA. They will remove its thermal shroud and gimbal locks, readying the SASA for operation.
Tanner will then descend from the truss assembly to connect thermal system umbilicals between the Z1 and P6 truss assemblies, while Noriega resumes work mating umbilical cables to the Z1 patch panel.
The remaining EVA tasks are designed to pave the way for the arrival of the U.S. Laboratory Destiny early next year. Tanner and Noriega then will remove umbilicals from Pressurized Mating Adapter–2 (PMA2) connecting them to a dummy panel located on that docking port preparing it for relocation to the aft end of the Destiny module during the STS-98/5A mission.
Noriega will then release cinches on the aft radiator of the early thermal control system in much the same procedure he followed for the PV Radiator task, and then relocate foot restraints to assist the astronauts who will perform a space walk during the STS-102/5A mission. At the same time, Tanner will begin connecting two electrical jumpers, called H-Jumpers, that will provide increased power capacity to the Zvezda and Zarya modules.
Tanner and Noriega will gather up their tools and hardware before heading back into Endeavour’s airlock concluding the second scheduled space walk of the mission.
EVA 3
The primary task of this planned 3 1/2 hour EVA is to install a device referred to as a floating potential probe (FPP), a science package to measure the electrical potential of the plasma field around the ISS.
The FPP package includes an antenna on the Unity module of the Space Station to receive the data transmitted from the FPP, and associated cabling and electronics inside the ISS to interleave the FPP data with Station data that is routinely sent to flight controllers on the ground for processing and analysis.
Tanner and Noriega will work together to assemble and attach the FPP science equipment, probe and antenna to the zenith bulkhead of the recently-installed P6 structure. They will attach the FPP package to the probe, inserting the probe in a foot restraint socket. They will then mount two potential probes and two small solar array panels to the FPP housing. After moving aside an EVA tool bag mounted on the Unity module, Tanner and Noriega will mate the antenna connector and mount the antenna on Unity, moving the EVA tool bag back into place.
During this third EVA they will also complete a task that was originally scheduled for the second space walk, reconnecting cables for the centerline berthing camera. Tanner will mount the robotic arm to mate a pre-routed cable for the centerline berthing camera to the early communications system antenna to provide the STS-98/5A crew with camera views to aid them in attaching the large lab module.
Tanner and Noriega also may complete additional "get ahead" tasks as time permits.
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