Spaceflight mission report: STS-117 (original) (raw)

Launch from Cape Canaveral (KSC) and landing on the EdwardsAFB, Runway 22.

The launch was originally planned for March 15, 2007 but postponed due to damage from a hail storm on February 26, 2007. Following the hailstorm atKSC on February 26, 2007, inspections of the stack found damage to the shuttle and the external tank. Hailstones as large as golf balls had created around 1,000-2,000 divots in the tank's foam insulation, damaged at least one Ice Frost Ramp on the tank, and caused minor surface damage to about 26 heat shield tiles on Atlantis's left wing.
On March 04, 2007 theSTS-117 stack was similarly rolled back into theVAB. Following additional inspections, repairs to the orbiter and tank were carried out to return Atlantis to flight readiness. After completion of the repairs, Atlantis (along with her distinctly speckled external tank) was rolled out to pad 39-A for the second time during the morning of May 15, 2007.
The hail damage to Atlantis caused major changes to the shuttle launch manifest at that time, pushing STS-118 back to August 08, 2007 (which could not have flown until the installation of theS3/S4 truss segment carried by Atlantis was completed),STS-120 back to October 23, 2007, and Atlantis's return on STS-122 back to a targeted launch date on December 06, 2007. Atlantis onSTS-122 eventually lifted off on February 07, 2008.

STS-117 (ISS-13AITS-S3 /ITS-S4) delivered to the International Space Station (ISS) the second starboard truss segment (the S3/S4 Truss) and its associated energy systems, including a set of solar arrays. During the course of the mission the crew installed the new truss segment, retracted one set of solar arrays, and unfolded the new set on the starboard side of the station.
After several months working aboard the station,NASA astronaut SunitaWilliams will return to Earth aboard Atlantis. The flight will also carry her successor, astronaut ClaytonAnderson, who arrived on Atlantis to begin his duty as anExpedition 15 Flight Engineer.
The exchange of ClaytonAnderson and SunitaWilliams was originally planned for theSTS-118 mission, for launch in August 2007. However, that flight, first set to fly in June, had to be postponed after an unexpected hail storm damaged Atlantis' external fuel tank and delayedSTS-117.
With the new plan, SunitaWilliams' mission on the station had approximately the same length as originally anticipated. SunitaWilliams launched to the station December 09, 2006, aboard the space shuttle Discovery as part of the STS-116 mission.

The mission delivered and installed the 17.5-ton S3/S4 truss segment to the starboard side of the integrated truss system of the orbital outpost. The truss, part of the station's girder-like backbone, is a mirror image of theP3/P4 truss installed during STS-115 in September 2006. The new truss segment includes a set of photo-voltaic solar arrays. When unfurled, the 240-foot (73.2 meters) arrays provide additional power for the station in preparation for the delivery of international science modules during the next two years.
Each of the 82 active array blankets that are grouped into 31.5 "bays" contains 16,400 silicon photovoltaic cells to convert sunlight into electricity. The truss also contains a Solar Alpha Rotary Joint (SARJ), which will rotate 360 degrees, clockwise or counterclockwise, to position theS4 andS6 solar arrays to track the sun.
Processes to activate theSARJ were modified afterSTS-115. During that mission, difficulties were encountered with software associated with the gears within the joint, and spacewalking astronauts had trouble loosening bolts during its structural preparation. Software to control theSARJ was updated, and the spacewalkers now will carry another tool, called a torque multiplier, to help remove any balky launch restraints.
The mission included the retraction of the starboard solar array, known as 2B, on theP6 truss atop the station, which would otherwise interfere with the rotation of the new starboard arrays. The retraction also prepared theP6 truss for its relocation to the outboard port side of the station later in 2007. Retraction began a day earlier than originally planned because of the tricky retraction of theP6 port side solar array during the STS-116 mission in December 2006. Atlantis' spacewalk teams were also prepared to assist the retraction.

The Starboard Three (S3) and Starboard Four (S4) integrated truss segments are the primary payload delivered on theSTS-117 mission and the heaviest space station payload to date. The principal functions of theS3 andS4 truss segments are to provide electrical power and data interfaces for future mission payloads and convert sunlight to electricity. The segments will include another set of Solar Array Wings (SAWs) and a second Solar Alpha Rotary Joint (SARJ).
The integrated truss segments started with Starboard zero (S0) as the center assignment and were numbered in ascending order out-ward to the port and starboard sides. Starboard is the right side and port is the left side of the truss structure. Z is zenith and is up.
FromS0, the truss segments areP1,P3,P4,P5 andP6 andS1,S3,S4,S5 andS6.P6 is on orbit and attached to segmentZ1 (zenith). The zenith is a spacer added to provide adequate space between the pressurized modules andP6.P6 eventually will be relocated and attached toP5. Plans for S2 and P2 segments were eliminated when the station design was scaled back.
TheS3 primary structure is made of a hexagonal-shaped aluminum structure and includes four bulkheads and six longerons, beams that connect the bulkheads. The secondary structure includes brackets, fittings, attach platforms, extravehicular activity equipment and miscellaneous mechanisms.
The majorS3 subsystems include theSARJ, Segment-to-Segment Attach System (SSAS) and Payload Attach System (PAS). TheS3 truss segment will provide mechanical, power and data interfaces to payloads attached to the four PAS platforms; axial indexing for solar tracking via theSARJ; translation and work site accommodations for the Mobile Transporter; accommodations for ammonia servicing of the out-board PV modules and two Multiplexer/Demultiplexers (MDMs). The MDMs are basically computers that tell other electrical components when to turn on and off and monitor hardware. TheS3 also provides a passive attachment point to theS1 segment via the SSAS and pass through of power and data to and from the outboard segments.
The SARJ continuously rotates to keep the SAW onS4 andS6 (S6 launched on shuttle mission STS-119) oriented toward the sun as the station orbits the Earth. Each SAW is also oriented by the BGA, which can change the pitch of the wing. Each wing measures 115 feet by 38 feet (35.1 by 11.6 meters) and extends out to each side of the Integrated Equipment Assembly. There are two wings onS4.
Major subsystems of theS4 truss are the port inboard Photovoltaic Module (PVM), the Photo-voltaic Radiator (PVR), the Alpha Joint Interface Structure (AJIS) and the Modified Rocketdyne Truss Attachment System (MRTAS).
TheS4 PVM includes all equipment outboard of theSARJ outboard bulkhead, namely the two Photovoltaic Array Assemblies (PVAAs) and the Integrated Equipment Assembly (IEA). The PVR provides thermal cooling for the IEA. The AJIS provides the structural transition betweenS3 andS4. Each PVAA consists of a SAW and BGA.S4 also contains the passive side of the MRTAS that will provide the structural attachment for theS5 truss.

During its first full day in orbit, crewmembers aboard Atlantis inspected the shuttle's heat shield. The crew was given an extra half-hour to sleep after being kept up late to finish downloading in-cabin video. Pilot LeeArchambault and Mission Specialists PatrickForrester and StevenSwanson used the shuttle's robotic arm and orbiter boom sensor system (OBSS) to inspect the heat shield on Atlantis’ wing leading edges and nose cap. Based on lessons learned during the previous three post-Columbia missions, duringSTS-117, the crew used new inspection procedures devised byNASA. The scans took less time, covered a larger area and they used a camera on the end of theOBSS to take close-up photographs at the same time the laser scanner was collecting data. The astronauts started with the starboard wing leading edge, making multiple passes up and down the wing to cover all the angles. After scanning the nose cap, they moved on to the port wing and repeated the procedure.

The shuttle launch was timed precisely to place the orbiter on the correct trajectory and course for its two-day chase of the station. Periodic engine firings gradually brought Atlantis to about 50,000 feet (15,240 meters) behind the station - the starting point for a final approach.
About 2.5 hours before docking, Atlantis' jets were fired during what is called the Terminal Initiation burn to begin the final phase of the rendezvous. Atlantis closed the final miles to the station during the next orbit.
As Atlantis moved closer to the station, the shuttle's rendezvous radar system and trajectory control sensor tracked the complex and provide range and closing rate data to the crew. During the final approach, Atlantis executed several small mid-course correction burns that placed Atlantis about 1,000 feet (304.8 meters) directly below the station.STS-117 Commander FrederickSturckow then manually controlled the shuttle for the remainder of the approach and docking.
He stopped the approach 600 feet (182.9 meters) beneath the station to ensure proper lighting for imagery prior to initiating the standard R-bar Pitch Maneuver (RPM), or backflip.
FrederickSturckow maneuvered Atlantis through a 9 minute, 360-degree backflip that allowed the station crew to take as many as 300 digital pictures of the shuttle's heat shield.
On verbal cue from Pilot LeeArchambault to the station crew, FrederickSturckow commanded Atlantis to begin a nose-forward, three-quarter of a degree per second rotational backflip.
The photos were taken out of windows in theZvezda Service Module with Kodak DCS 760 digital cameras outfitted with 400 mm and 800 mm lenses. The imagery was one of several inspection techniques to determine the health of the shuttle's thermal protection system, including the tiles and reinforced carbon-carbon wing leading edges and nosecap.
The photos were downlinked through the station's Ku-band communications system for analysis by systems engineers and mission managers.
When Atlantis completed its rotation, its payload bay was facing the station. FrederickSturckow then moved Atlantis to a position about 400 feet (121.9 meters) directly in front of the station in preparation for the final approach to docking to theDestiny docking port.
The shuttle's crew members operated laptop computers processing the navigational data, the laser range systems and Atlantis' docking mechanism.
Using a view from a camera mounted in the center of the Orbiter Docking System, FrederickSturckow precisely matched up the docking ports of the two spacecraft. If necessary, he paused 30 feet (9.14 meters) from the station to ensure proper alignment of the docking mechanisms.
For Atlantis' docking on June 10, 2007, FrederickSturckow maintained the shuttle's speed relative to the station at about one-tenth of a foot per second (3 centimeters per second) (while both Atlantis and the station were traveling at about 17,500 mph = 28,163 km/h), and kept the docking mechanisms aligned to within a tolerance of three inches (7.6 centimeters). When Atlantis made contact with the station, preliminary latches automatically attached the two spacecraft. Immediately after Atlantis docked, 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 the station.
Once the motion between the spacecraft had stopped, the docking ring was retracted to close a final set of latches between the two vehicles.

When Atlantis arrived at the station two days after launch, the Expedition 15 Commander FyodorYurchikhin andFlight Engineers OlegKotov and SunitaWilliams greeted the six-person shuttle crew. FyodorYurchikhin and OlegKotov arrived at the complex April 09, 2007 following their April 07, 2007 launch on the Russian Soyuz TMA-10 from the Baikonur Cosmodrome in Kazakhstan. They returned to Earth in October 2007 after the arrival of the next station crew. SunitaWilliams came to the station on Discovery'sSTS-116 flight in December 2006. She returned at the end ofSTS-117 onboard Atlantis.

Following docking, Pilot LeeArchambault and Mission Specialist PatrickForrester used the shuttle's Canadarm to grapple theS3/S4 truss, lift it from its berth in the payload bay, and maneuvered it for handover to the station'sCanadarm2. After hatch opening, SunitaWilliams used theCanadarm2 to take the truss from the shuttle’s robotic arm. That task was completed at 00:28UTC marking the completion of the handover. The truss remained grappled to the station’s arm until next day's installation.

The firstEVA was performed by JamesReilly and JohnOlivas on June 11, 2007 (6h 15m). After venturing out of theQuest airlock into space, Mission Specialists JamesReilly and JohnOlivas released launch restraints on the four Solar Array Blanket Boxes, which house the folded solar arrays. They made final attachment of bolts, cables and connectors, and began preparations for the activation of the truss. The two spacewalkers rotated the array canisters into their normal position for deployment on the next day. The start of the spacewalk was delayed for about an hour after the station temporarily lost attitude control when the station's control moment gyroscopes (CMGs) went offline. The spacewalk started after station's gyroscopes were initialized by flight controllers.

NASA's Mission Management Team also decided to extend Atlantis' mission by two days and to add a fourth spacewalk. John Shannon, the head ofNASA'sSTS-117 Mission Management Team during the day's mission briefing told reporters that the extra time would give the crew to complete theISS assembly tasks and allow ground engineers to draw up plans to repair the damaged blanket on theOMS pod of Atlantis.

The successful deployment of theS3/S4 solar arrays was the highlight of the flight day 5, adding significantly to theISS power generation capabilities. Prior to crew wake up, station controllers began unfurling the solar array attached to theS3/S4 truss segment. Shuttle crew then took over, unfolding one wing at a time in stages, pausing to let the sun warm the solar array panels which helped to prevent the thin individual panels from sticking together. The crew finished unfolding the first wing at 16:29UTC and the second at 17:58UTC.
There were continuing problems with the station's electrically-driven gyroscopes, the preferred, non-propulsive, method for controlling theISS due to a problem with a Russian navigation computer. The navigation computer problem started when flight controllers attempted to turn attitude control over to theISS computers after letting shuttle computers handle it while the arrays were unfolded. The navigation computer would not allow them to do so, and forced a reboot of the main Russian command and control computer. The forced reboot triggered an alarm enunciating the problem to the crew and ground controllers.
The issues appeared to have been resolved by the end of the day and the station's gyroscopes took over attitude control shortly after 08 pm CDT. That was followed by relocation of the Mobile Transporter in preparation ahead the next day's spacewalk. The crew or shuttle/station combined stack never was in danger throughout the troubleshooting efforts.

The secondEVA by PatrickForrester and StevenSwanson occurred on June 13, 2007 (7h 16m). The main task of the spacewalk was to prepare the Solar Alpha Rotary Joint (SARJ) between theS3 andS4 Truss segments for rotation.
After exitingQuest at 18:03UTC the two spacewalkers moved up theP6 Truss to monitor the retraction of the 2B Solar Array and to assist if required. PatrickForrester, was in a foot restraint on the station'sCanadarm2, and StevenSwanson had specially-prepared tools to use to help the panels of photovoltaic cells fold properly. Flight controllers were able to get seven and a half of the 31.5 solar array bays folded. Then, PatrickForrester and StevenSwanson were able to poke and prod another five and a half bays worth of panels into folding correctly (some 45 feet = 13.7 meters) before moving on to theSARJ.
PatrickForrester and StevenSwanson completedEVA 2 with mixed results. The duo removed all of the launch locks holding theSARJ in place. The spacewalkers had planned to remove theSARJ's launch restraints as well, but ran into problem when PatrickForrester tried to install a drive-lock assembly. They discovered that theS3/S4 SARJ motor control circuits were wired in reverse. As such commands being sent to the drive-lock assembly were actually being received by a drive-lock assembly that was installed duringEVA 1. So, one launch lock restraint was left in place to prevent the possibility of undesired rotation.

After the end of the spacewalk problems became serious when navigation computers in the Russian segment did not operate. Over the next days, the computers were repaired. Meanwhile Mission Control had decided to extend the mission duration.

On flight day 7 a computer malfunction on the Russian segments of theISS occurred at 06:30UTC and left the space station without orientation control. A successful restart of the computers resulted in a false fire alarm which awakened the crew at 11:43UTC. Engineers theorized that the newS4 solar array, or components in the circuitry delivering that power to the Russian segment of theISS, triggered some subtle change in theISS electrical grid
The solar array blanket atop theP6 truss was furled to a little more than half its original length by the Atlantis and the station crews. Commander FrederickSturckow, along with Pilot LeeArchambault, Mission Specialist SunitaWilliams andFlight Engineer ClaytonAnderson, meticulously retracted the solar array blanket another three bays worth of panels. The crew carefully sent commands to retract the array as much as possible ahead ofEVA 3. By last count, 15 and a half of the 31 and half bays remained to be folded into a 20-inch-deep (51 centimeters) protective box.

The thirdEVA by JamesReilly and JohnOlivas was conducted on June 15, 2007 (7h 58m). While JohnOlivas anchored to the end of Atlantis' robot arm was repairing theOMS pod, JamesReilly installed an external hydrogen vent for the oxygen generating system insideDestiny laboratory. By using his helmet camera, JohnOlivas beamed down close-up views of the torn insulation and surrounding blankets to help flight controllers assess the system's condition. John Olivas spent two hours stapling and pinning down a thermal blanket on theOMS pod.
Flight controllers from Houston also radioed JamesReilly that they had decided to have him disconnect the P-12 connector that was installed duringEVA 1 since the Russian flight controllers were planning to make an attempt to restart the problematic computers in theISS. Even though the connector was not in use at that time, engineers decided to have JamesReilly disconnect it to make sure that it was not causing any electrical noise or grounding issues that might have played a role in the computer trouble.
When those tasks were completed, the two astronauts along with their colleagues inside the shuttle and station and flight controllers in Houston completed the final retraction of the starboardP6 truss element. The retraction that required 28 commands was completed and latches closed. The successful folding paved the way to relocate theP6 truss to its permanent location during STS-120. All tasks were completed successfully.

Thefourth and unplanned spacewalk was performed by PatrickForrester and StevenSwanson on June 17, 2007 (6h 29m) to activate the new solar array rotation mechanismSARJ and ready the lab complex for a critical sequence of upcoming construction flights; work included the removal of a keel pin and drag link fromS3, the complete bolting down of a piece of debris shielding on theDestiny laboratory, the installation of a computer network cable on Unity, and the removal of a Global Positioning System antenna.
StevenSwanson and PatrickForrester retrieved a TV camera and its support structure from a stowage platform attached to theQuest Airlock and installed it on theS3 truss. They then verified the Drive Lock Assembly (DLA) 2 configuration and removed the last sixSARJ launch restraints. The two astronauts cleared the path on theS3 truss for the Mobile Base System by removing temporary rail stops and hardware that had secured theS3/S4 truss segments in the shuttle's payload bay. The work completed the major tasks assigned for theSTS-117 mission.
The pair then began some of the get-ahead tasks mission managers had hoped to complete. The two spacewalkers installed a computer network cable on the Unity node that was to permit astronauts in the U.S. segment of the station to command systems in the Russian segment and opened the Hydrogen vent valve on theDestiny laboratory installed by Mission Specialist JamesReilly duringEVA 3. StevenSwanson and PatrickForrester also attempted to bolt down two debris shield panels that could not be put back in place during an earlier spacewalk. Since the two were also not able to get it anchored, they tethered the panels on the space station's service module.

Overnight, ground controllers planned to test theSARJ, ordering a small 5-degree rotation just to verify normal operations. Throughout flight day 10, the Russian central computer and terminal computers continued in stable operation.
The astronauts hauled the last bits of cargo between the shuttle and the space station while flight controllers on Earth tested the station's resuscitated Russian control and navigation computers after they crashed last week. In the morning the shuttle maneuvered the Atlantis/ISS complex into position for a water and waste water dump and after it maneuvered back, attitude control was switched to and from Russian command successfully.

At undocking time, the hooks and latches were opened, and springs pushed the shuttle away from the station. Atlantis' steering jets were shut off to avoid any inadvertent firings during the initial separation.
Once Atlantis was about two feet (61 centimeters) from the station and the docking devices were clear of one another, LeeArchambault turned the steering jets back on and manually controlled Atlantis within a tight corridor as the shuttle separated from the station.
Atlantis moved to a distance of about 450 feet (137.2 meters), where LeeArchambault began to fly around the station in its new configuration.
Once Atlantis completed 1.5 revolutions of the complex, LeeArchambault fired Atlantis' 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 re-entry.

During the separation from the station, a camera in the cargo of Atlantis bay observed numerous objects what could have been harmless pieces of ice and one much larger, more distinct piece of debris slowly floating away. It was not clear whether the objects originated from the shuttle or the space station. Around 21:30UTC, Commander FrederickSturckow reported yet another piece of debris leaving the area of Atlantis. FrederickSturckow identified them to the mission control in Houston as "little phenolic-looking, kind of tan-looking washers with four slots" that are used to tie down the Multi-Layer Insulation blankets in the payload bay.

The landing was running a day late because of blustery Florida weather.