Spaceflight mission report: STS-126

Launch from Cape Canaveral (KSC) and landing on the Edwards AFB, Runway 04.

Originally scheduled to fly on STS-126 was Joan Higginbotham, who was a mission specialist on STS-116. On November 21, 2007, NASA announced a change in the crew manifest due to Joan Higginbotham's decision to leave NASA to take a job in the private sector. Stephen Bowen was originally assigned to STS-124 but was moved to STS-126 to allow Discovery to rotate Gregory Chamitoff with Garrett Reisman.

STS-126 (ISS-ULF-2 MPLM Leonardo) included the Leonardo Multi-Purpose Logistics Module (MPLM) on its fifth spaceflight. Leonardo held over 14,000 pounds of supplies and equipment. Among the items packed into the MPLM were two new crew quarters racks, a second galley (kitchen) for the Destiny laboratory, a second Waste and Hygiene Compartment (WHC) rack (lavatory), the advanced Resistive Exercise Device (aRED), two water reclamation racks, spare hardware, and new experiments. Also included in Leonardo was the General Laboratory Active Cryogenic ISS Experiment Refrigerator, or GLACIER, a double locker cryogenic freezer for transporting and preserving science experiments. The shuttle also carried irradiated turkey, candied yams, stuffing and dessert for a special Thanksgiving meal at the station, as well as an Official Flight Kit with mementos for those who supported the astronauts and helped them complete their mission successfully.
The crew conducted four spacewalks to service and lubricate the complex's two Solar Alpha Rotary Joints (SARJ) that allow the station's photovoltaic cells to revolve like paddlewheels and point at the sun. The starboard SARJ has had limited use since September 2007. The spacewalkers also installed a new nitrogen tank, a global positioning system, antenna, and a camera on the station's Integrated Truss Assembly.
The shuttle delivered a new Flight Engineer, Sandra Magnus to join the Expedition 18 crew, and return Flight Engineer Gregory Chamitoff to Earth.
Also carried was a Lightweight MPESS Carrier (LMC) carrying a Flex Hose Rotary Coupler (FHRC) and returning a Nitrogen Assembly Tank from ‘Quest’ for refurbishment.

There are two Solar Alpha Rotary Joints (SARJs) on the International Space Station. They connect the Port 3 and Port 4 (left side) truss segments and the Starboard 3 and Starboard 4 (right side) segments. P3/P4 was flown up on the STS-115 mission on September 09, 2006, while S3/S4 was flown up on the STS-117 mission June 08, 2007. The SARJ is a 10.5-foot diameter (129.5 inch = 3.2 meters) rotary joint that tracks the sun in the alpha axis that turns four port and four starboard solar arrays wings. The eight solar array wings (on P4, P6, S4 and S6) are used to convert solar energy to electrical power. The SARJ continuously rotates to keep the solar array wings on S4 and S6 and P4 and P6 oriented toward the sun as the station orbits the Earth. The SARJ rotates 360 degrees every orbit or about 4 degrees per minute.
The SARJ weighs approximately 2,506 pounds (1,137 kg) and is made of aluminum and corrosion resistant steel. The major components of the SARJ are the Utility Transfer Assembly (UTA), Trundle Bearing Assemblies (TBA) (12 per joint), race rings (2 per joint) and Drive/Lock Assembly (DLA) (2 per joint) and the Rotary Joint Motor Controller (RJMC) (2 per joint). The SARJ can spin 360 degrees using bearing assemblies and a control system to turn. All of the power flows through the UTA in the center of the SARJ. A large 10.5-foot (129.5-inch = 39.5 meters diameter), 229-pound (104 kg) geared race ring is secured to the structure by the TBAs and driven by the DLA using the software control commanded from the DLA/RJMC pair. The DLA engages the teeth of the race ring to rotate the SARJ. The gold plating on the TBA rollers is transferred from the roller to the race ring to lubricate the ring to create a lubricating film. Each SARJ has two race rings, an inboard race ring that is attached to the P3 or S3 truss and an outboard race ring that is attached to the P4 or S4 truss segment. The 12 TBAs are attached to the inboard SARJ race ring via mounts that do not rotate. The TBAs are the structural connection in orbit between the inboard and outboard race rings. The DLA also are attached to the inboard SARJ structure and have "follower assemblies" that act in the same fashion as the TBAs, helping to locate the driving gear relative to the race ring teeth. The UTA is an electrical roll ring assembly that allows transmission of data and power across the rotating interface so it never has to unwind. The UTA passes through the center, or hub, of the joint so it interfaces with both the inboard and outboard segments. The roll ring assemblies allow the outboard elements to rotate relative to the inboard elements while providing continuous data and power transmission.

The second day in space for the crew was devoted to completing the initial inspection of Endeavour's heat shield. Using the shuttle's robotic arm and the Orbiter Boom Sensor System (OBSS), the crew took detailed images of the exterior of the orbiter for the image analysis team to review. The crew also continued to prepare for docking with the station on Sunday, by extending the docking ring, installing the centerline camera, and organizing the tools needed for rendezvous with the station.

Rendezvous began with a precisely timed launch which put the shuttle on a trajectory to chase the International Space Station. A series of engine firings over the next two days brought Endeavour to a point about 50,000 feet (15,240 meters) behind the station.
Once there, Endeavour started its final approach. About 2.5 hours before docking, the shuttle's jets were fired during what is called the terminal initiation burn. The shuttle covered the final miles to the station during the next orbit.
As Endeavour moved closer to the station, its rendezvous radar system and trajectory control sensor gave the crew range and closing-rate data. Several small correction burns placed Endeavour about 1,000 feet (304.8 meters) below the station.
Commander Christopher Ferguson, with help from Pilot Eric Boe and other crew members, manually flew the shuttle for the remainder of the approach and docking.
He stopped Endeavour about 600 feet (182.9 meters) below the station. Once he determined there is proper lighting, he maneuvered Endeavour through a nine-minute back flip called the Rendezvous Pitch Maneuver known as R-bar Pitch Maneuver (RPM). That allowed the station crew to take as many as 300 digital pictures of the shuttle's heat shield. Station crew members Michael Fincke and Gregory Chamitoff used digital cameras with 400 mm and 800 mm lenses to photograph Endeavour's upper and bottom surfaces through windows of the Zvezda Service Module. The 400 mm lens provided up to 3-inch (7.6 centimeters) resolution and the 800 mm lens up to 1-inch (2.5 centimeters) resolution. The photography was one of several techniques used to inspect the shuttle's thermal protection system for possible damage. Areas of special interest included the thermal protection tiles, the reinforced carbon-carbon of the nose and leading edges of the wings, landing gear doors and the elevon cove. The photos were downlinked through the station's Ku-band communications system for analysis by systems engineers and mission managers. When Endeavour completed its back flip, it was back where it started, with its payload bay facing the station.
Christopher Ferguson then flew Endeavour through a quarter circle to a position about 400 feet (121.9 meters) directly in front of the station. From that point he began the final approach to docking to the Pressurized Mating Adapter 2 at the forward end of the Harmony node.
The shuttle crew members operated laptop computers processing the navigational data, the laser range systems and Endeavour's docking mechanism.
Using a video camera mounted in the center of the Orbiter Docking System, Christopher Ferguson lined up the docking ports of the two spacecraft. He paused 30 feet (9.14 meters) from the station to ensure proper alignment of the docking mechanisms.
He maintained the shuttle's speed relative to the station at about one-tenth of a foot per second (3 centimeters per second), while both Endeavour and the station were moving at about 17,500 mph (28,163 km/h). He kept the docking mechanisms aligned to a tolerance of three inches (7.6 centimeters).
When Endeavour made contact with the station on November 16, 2008, preliminary latches automatically attached the two spacecraft. The shuttle's steering jets were deactivated to reduce the forces acting at the docking interface. Shock absorber springs in the docking mechanism dampened any relative motion between the shuttle and station.
Once motion between the shuttle and the station had stopped, the docking ring was retracted to close a final set of latches between the two vehicles.

A few hours after Endeavour's docking on the third day of the flight, Sandra Magnus and Gregory Chamitoff exchanged custom-made Russian Soyuz spacecraft seat liners. With that exchange, Sandra Magnus became a part of the Expedition 18 space station crew, and Gregory Chamitoff became part of Endeavour's crew.
Sandra Magnus joined Expedition Commander Michael Fincke and Flight Engineer Cosmonaut Yuri Lonchakov who were launched to the complex in the Soyuz TMA-13 spacecraft on October 12, 2008 from the Baikonur Cosmodrome in Kazakhstan. In the spring 2009, Sandra Magnus returned to Earth on shuttle mission STS-119, while Michael Fincke and Yuri Lonchakov returned in the Soyuz in April 2009.

The first EVA by Heidemarie Stefanyshyn-Piper and Stephen Bowen occurred on November 18, 2008 (6h 52m) to replace a depleted nitrogen tank and a device used to help the flow of coolant from the truss, the backbone of the station. They also removed thermal covers from the Japanese Kibo module to inspect the berthing mechanism where the module's exposed facility will be installed during the STS-127 mission in 2009. They also started inspecting, cleaning and lubricating the starboard SARJ and begin replacing 11 of 12 trundle bearings. One was replaced during the STS-124 mission in June 2008.
The first order of business was to swap the external equipment just delivered by the space shuttle with equipment that was brought back to Earth. Heidemarie Stefanyshyn-Piper removed an empty nitrogen tank assembly that has been waiting on the external stowage platform 3 on the port, or left, side of the station's truss since the June 2008 STS-124 mission. After installing a foot restraint on the end of the station's robotic arm to stand in, Heidemarie Stefanyshyn-Piper removed the tank and carried it as she rode the arm to the shuttle's cargo bay.
Stephen Bowen helped Heidemarie Stefanyshyn-Piper remove the nitrogen tank, then took care of some minor tasks, including retrieving a camera and closing a window flap on Harmony's zenith common berthing mechanism. Stephen Bowen met Heidemarie Stefanyshyn-Piper in the cargo bay to help stow the tank and remove a spare flex hose rotary coupler, or FHRC. FHRCs are used to transfer liquid ammonia across the rotary joints that allow the station's radiators to rotate.
Heidemarie Stefanyshyn-Piper carried the FHRC back to the stowage platform via robotic arm, where she and Stephen Bowen installed it for future use. Then, while Heidemarie Stefanyshyn-Piper climbed off of the robotic arm, Stephen Bowen removed some insulation from the common berthing mechanism that was used to attach the Japanese external facility to the Kibo laboratory.
When those tasks were done, the spacewalkers started the mission's first round of starboard SARJ maintenance. The rotary joint has 22 protective insulation covers, of which no more than six can be removed at any one time. Heidemarie Stefanyshyn-Piper began by opening cover eight. Cover seven was removed and left off during an inspection on a previous spacewalk. With the insulation covers removed, Heidemarie Stefanyshyn-Piper had access to the 10^th of the joint's trundle bearing assemblies, or TBAs, which connect the two halves of the joint and allow one side to rotate while the other stays still. Meanwhile, Stephen Bowen worked under covers 22 and one, on TBA six.
With the covers removed, Heidemarie Stefanyshyn-Piper and Stephen Bowen then removed their respective TBAs and stowed them in special bags designed to hold one TBA apiece. With that equipment out of the way, the spacewalkers were able to begin cleaning the area under the open covers. First, they used a wet wipe to remove debris from the cleaner areas of the joint, then to clean off the damaged outboard outer canted surface.
Next, they used a grease gun to add a line of grease to the outer canted surface and used a scraper similar to a putty knife to remove some of the debris that has become "pancaked" on the surface. They cleaned the scrapers off inside of a debris container to prevent metal flakes from floating away, and then used a dry wipe to remove the grease from the area. Then they gave the entire area a final wipe with a dry wipe to remove any residual grease and debris.
Once the area is clean, the astronauts could begin lubricating the surface of the outboard ring. They use a grease gun with a special, j-shaped nozzle to add grease to the inner canted surface, and a straight-nozzle grease gun for the outer canted and datum A surfaces.
Finally, before closing the covers, Heidemarie Stefanyshyn-Piper and Stephen Bowen installed clean trundle bearing assemblies in place of the ones they removed. Heidemarie Stefanyshyn-Piper then repeated the process on TBA 11, under covers nine and 10. However, she did not reinstall TBA 11 until the second spacewalk.
About halfway into the spacewalk, one of the grease guns that Heidemarie Stefanyshyn-Piper was preparing to use on the SARJ released some braycote grease into her crew lock bag, which is the tool bag the spacewalkers use during their activities. As she was cleaning the inside of the bag, it drifted away from her and toward the aft and starboard portion of the International Space Station. Inside the bag were two grease guns, scrapers, several wipes and tethers and some tool caddies. Stephen Bowen then shared bag and equipment with her.

On flight day 6 there were no EVA activities and the crew installed two crew quarters racks into the Harmony node, and installed a rack with equipment to be returned to Earth into the MPLM (Leonardo). The crew also began working on activating the Water Recovery System, so that samples of water from two areas could be taken and returned to Earth with Endeavour.

The second EVA was performed by Heidemarie Stefanyshyn-Piper and Shane Kimbrough on November 20, 2008 (6h 45m) to relocate two equipment carts, setting the stage for the installation of the starboard S6 truss (scheduled for February 2009). The spacewalkers also lubricated the end effector, or hand, of the Canadarm2, the station's robotic arm. They also continued lubricating the starboard SARJ and replacing trundle bearings.
The first task of the second spacewalk gave Shane Kimbrough a chance to ride the station's robotic arm. He and Heidemarie Stefanyshyn-Piper moved the station's two Crew and Equipment and Translation Aid, or CETA, carts, the rail carts that allow astronauts to move equipment along the station's truss, from their current homes on the starboard side of the station's Mobile Transporter (MT) to the port side.
Heidemarie Stefanyshyn-Piper got the carts ready for transfer by moving them into position and unlocking their wheel bogies. Shane Kimbrough first carried CETA 1 and then CETA 2 as he was flown on the robotic arm from one side of the MT to the other. Heidemarie Stefanyshyn-Piper met him there each time, to install the carts in their new locations.
When that task was done, Shane Kimbrough climbed off of the robotic arm and removed the foot restraint Heidemarie Stefanyshyn-Piper installed on the first spacewalk. This gave him access to the arm's latching end effector, or LEE, the snares that allow it to grasp equipment. Inside the station, Donald Pettit and Sandra Magnus commanded the LEE, which has been experiencing some sticky spots, to open and close its snares. Shane Kimbrough applied lubricant to the LEE's snare bearings and rotated the bearings using needlenose pliers to ensure the lubricant covers the bearings.
Meanwhile, Heidemarie Stefanyshyn-Piper returned to the starboard SARJ to continue its cleaning and lubrication. Following the first spacewalk, the SARJ was rotated so that the areas Heidemarie Stefanyshyn-Piper and Stephen Bowen already cleaned were under the joint's two drive lock assemblies, which cannot be removed easily. Heidemarie Stefanyshyn-Piper reopened covers nine and 10 and cleaned the new area under them, before reinstalling TBA 11, which she removed during the first spacewalk, and reclosing the covers.
Next Heidemarie Stefanyshyn-Piper removed and replaced TBAs eight and nine under cover five. When Shane Kimbrough finished his work on the robotic arm, he joined her at the SARJ and work on TBAs 12, under covers 11 and 12.

On flight day 8 Michael Fincke and Sandra Magnus tested latches on the Exposed Facility Berthing Mechanism for the Japanese Kibo laboratory. Sandra Magnus continued with the installation of the Total Organic Carbon Analyzer (TOCA), while engineers on the ground worked through troubleshooting of the Urine Processor Assembly. The component ran initially on Thursday evening, but shut itself down during that initial test, and shut down again the following morning after two hours of operations.

The third EVA by Heidemarie Stefanyshyn-Piper and Stephen Bowen was conducted on November 22, 2008 (6h 57m) to complete starboard SARJ cleaning, lubricating and trundle bearing work.
The third spacewalk of the mission was completely devoted to work on the starboard SARJ. Using the same methods, Heidemarie Stefanyshyn-Piper opened covers 13 and 14, removed TBA one, cleaned and lubricated the area, installed a new TBA and closed the covers. She repeated the process on TBA two under covers 15 and 16 and TBA three under covers 17 and 18.
Stephen Bowen did the same for TBA four under covers 19 and 20, TBA six under covers 22 and one and TBA seven under covers two and three. He also removed TBA five under cover 20; however, it was replaced on a previous spacewalk, so he simply cleaned and re-installed it.

The two crews (Station and Shuttle) continued transfer operations on Flight day 10, and Michael Fincke and Donald Pettit worked together to reconfigure the Urine Processing Assembly (UPA) to try to dampen any vibration that may be contributing to the unit's shutting down prematurely. The unit had continued to operate sporadically, shutting itself down after two to three hours of operations, and the engineers on the ground were still evaluating the possible causes and solutions.

The fourth and final EVA by Stephen Bowen and Shane Kimbrough was performed on November 24, 2008 (6h 07m) to remove several thermal covers on the port SARJ. Shane Kimbrough lubricated the port SARJ, while Stephen Bowen reinstalled the thermal insulation covers (removed on first EVA) on Kibo. He then installed two GPS antennae on Kibo's logistics module, while Shane Kimbrough installed a new TV camera on the truss. Meanwhile the managers on the ground had decided to extend Endeavour's mission to allow the crews more time to resolve the issues with the Urine Processing Assembly. And the UPA finally appeared to be functioning normally after the modifications performed by the crew on orbit.
The mission's final spacewalk required careful coordination, as the spacewalkers performed preventative maintenance on the station's port SARJ, which currently was functioning well. Shane Kimbrough had just the one spacewalk to lubricate the same surface area that was lubricated over three spacewalks on the starboard side.
To make that possible, he and Stephen Bowen opened covers 6, 7, 10, 11, 14 and 15, and left them open for most of the spacewalk. Shane Kimbrough then lubricated the exposed area and moved away so that flight controllers on the ground could rotate the joint 180 degrees. That helped spread the grease, and expose new, unlubricated areas under the open covers.
While the joint was rotating, Shane Kimbrough returned to the Quest airlock to retrieve a video camera. He installed the camera on the first port segment of the station's truss, where it will be used next year to provide views of the robotic arm's capture and docking of the first Japanese H-2 Transfer Vehicle.
Shane Kimbrough then moved back to the port SARJ, greased the newly exposed areas and closed the covers.
Meanwhile, Stephen Bowen worked on several projects at the Japanese Kibo module. He reinstalled the common berthing mechanism's insulation that he removed during the first spacewalk. Next, he tucked in the module's robotic arm grounding tabs, which are obscuring the view of the arm's camera, by wrapping the tabs around a cable and Velcroing them together.
Afterward, Stephen Bowen installed three spacewalk handrails, two worksite interfaces and two Global Positioning Satellite (GPS) antennae on Kibo's exterior. The H-2 Transfer Vehicle will use the GPS antennae to navigate to the space station.
Both astronauts wrapped up the spacewalks by taking photographs. Stephen Bowen photographed the radiators on the first port and starboard truss segments, using both regular and infrared cameras. In September 2008, ground controllers noticed damage to one panel of the starboard radiator.
Blemishes have been noticed on the trailing umbilical system cable of the mobile transporter, so Shane Kimbrough was asked to photograph it as well. The photographs were used by teams on the ground to determine the cause of the damage and blemishes and decide what action, if any, should be taken.

On November 26, 2008 Donald Pettit and Shane Kimbrough used the station’s Canadarm2 to move Leonardo from the Harmony module and placed in the shuttle’s cargo bay at 21:52 UTC. Heidemarie Stefanyshyn-Piper packed up equipment and supplies used for the four spacewalks and moved them to Endeavour for return, while Sandra Magnus continued work on the station’s new regenerative life support system. She drained a condensate collection tank to create the optimum ratio of condensate and distillate from the Urine Processor Assembly (UPA), and gathered additional water samples for testing

At undocking time, the hooks and latches were opened and springs pushed the shuttle away from the station. Endeavour's steering jets were shut off to avoid any inadvertent firings during the initial separation.
Once Endeavour was about two feet (61 centimeters) from the station and the docking devices were clear of one another, Eric Boe turned the steering jets back on and manually controlled Endeavour within a tight corridor as the shuttle separated from the station.
Endeavour moved to a distance of about 450 feet (137.2 meters), where Eric Boe began to fly around the station. Once Endeavour completed 1.5 revolutions of the complex, Eric Boe fired Endeavour's jets to leave the area. The shuttle moved about 46 miles (74 km) from the station and remained there while ground teams analyzed data from the late inspection of the shuttle's heat shield. The distance was close enough to allow the shuttle to return to the station in the unlikely event that the heat shield is damaged, preventing the shuttle's safe re-entry.

Due to bad weather at the primary landing site on Cape Canaveral (KSC) the Endeavour landed with two orbits delay at the Edwards AFB.