The mission is also referred to as ISS-13A by the ISS program. The Amission 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. STS-117 also brought Expedition 15 crewmember Clayton Anderson to the station, and returned with ISS crewmember Sunita Williams.
This mission was the 118th Space Shuttle flight, the 28th flight for Atlantis and the 21st U.S. flight to the ISS. The launch of STS-117 marks the 250th orbital human spaceflight. The completion of the mission leaves thirteen flights remaining in the Space Shuttle program until its end in 2010, excluding two as-yet-unconfirmed Contingency Logistic Flights.
On June 11, NASA mission managers announced a two-day extension of the mission, adding a fourth extra-vehicular activity (EVA). These two days were inserted into the mission timeline after flight day 8. This possibility had been discussed prior to launch. Because of launch day and thus rendezvous day uncertainty the decision to extend was deferred until after launch. The repair of the gap in the Orbital Maneuvering System (OMS) thermal blanket (heat shielding) was conducted during EVA 3.
Because of the cancellation of landing opportunities on June 21st because of weather, STS-117 is the longest mission for Atlantis, landing at Edwards Air Force Base on June 22nd.
Astronaut Mark Polansky was originally slated to pilot this mission, but was moved to STS-116, which he commanded. Also assigned to the flight were Joan Higginbotham and Richard Mastracchio, who were moved to missions STS-116 and STS-118 respectively.
The crew also folded up the other side of the solar arrays in the P6 truss segment.
|Bay 1-2||Orbiter Docking System EMU 1-2||1800 kg? 240 kg?|
|Bay 3P?||APCU (Assembly Power Converter Unit) (28VDC-to-124VDC) with SPDU (Station Power Distribution Unit)||2 x 35kg 20kg|
|Bay 4-12||Truss segment S3/S4||16183 kg|
|Sill||OBSS 201||450 kg?|
|Sill||RMS 301||390 kg|
|Total 19083 kg|
STS-117 was originally planned to launch on March 16, but the launch date was later moved forward in order to extend the launch window and increase the chances of a successful launch within that time frame. In preparation for this earlier launch date, Atlantis was transported to the Vehicle Assembly Building on February 7. First motion was at 6:19 a.m. EST.
Following the arrival of the Orbiter in the assembly facility, she was fitted with two bridge cranes that lifted her vertically, to position her for mating to the external fuel tank and solid rocket boosters, already in place atop the mobile launcher platform. The mating of the Orbiter to the stack occurred on February 12. The rest of the pre-launch preparations also continue to proceed according to plan, with the payload canister, containing the S3/S4 Truss and a set of solar arrays, arriving at the launch pad at 2:54 a.m. EST on Monday, February 12. The canister lift began at 5:40 a.m. EST the same morning, ready for transfer of the ISS truss segments and other cargo into the Payload Changeout Room on the newly-refurbished rotating service structure of pad 39A.
Atlantis was originally scheduled to begin her rollover to launch pad 39A (the first Shuttle launch at 39A in four years) on February 14, but due to erratic chamber pressure readings on one of the Operational Pressure Transducers (OPTs) on the forward skirt area of the right-hand SRB, the rollout was delayed to 7:00am EST on the morning of Thursday, February 15. Various problems, including a generator transfer issue to the mobile launcher platform, meant that first movement of the stack was delayed from the scheduled rollout time and did not occur until 8:19am EST. The 3.4 mile, six-hour journey to the launchpad concluded that afternoon, with Atlantis arriving at the launch pad at 3:09pm EST. It was decided that the issue with the OPT would be solved on the launch pad, a task which may require all six transducers on the STS-117 stack being removed and replaced.
The mission astronauts travelled from Houston to the Kennedy Space Center on February 21 to participate in the Terminal Countdown Demonstration Test. The astronauts were at the center from February 21-23, during which time they practiced launch activities, carried out safety exercises, inspected the payload and concluded the test with a simulated main engine cut-off exercise. They then returned to Houston via T-38 jets, planning to return to Kennedy Space Center a few days before launch. The next milestone in the launch preparations was the Flight Readiness Review from February 27-28, during which time managers, engineers and contractors examined the readiness of the Space Shuttle, flight crew and payloads to determine whether everything was set to proceed for launch.
Following a hailstorm at the center on February 26, inspections of the stack found damage to the orbiter 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 May 8 1999, hail had damaged the external tank of a prior Shuttle mission, STS-96, while it was on the launch pad. The orbiter for that mission, Discovery, was returned to the VAB, and inspections revealed more than 650 divots in the tank's outer foam. After repairs, launch of that mission proceeded smoothly.
On March 4, 2007 the STS-117 stack was similarly rolled back into the VAB. 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 39A for the second time during the morning of May 15. Atlantis was successfully launched from pad 39A on June 8, following a second Flight Readiness Review on May 30 and 31.
The hail damage to Atlantis caused a major change to the shuttle launch manifest, pushing STS-123 back into February 2008, STS-118 (which cannot fly until the installation of the S3/S4 truss segment carried by Atlantis is complete, as its S5 truss payload is mounted to the S4 segment) estimated to launch on August 9, STS-120 launching on October 20, and Atlantis's return on STS-122 scheduled for its December 6 launch date.
NASA has announced that it was possible, albeit unlikely, that one of 24 Composite Overwrap Pressure Vessels onboard Atlantis could have burst before launch, damaged the orbiter and wounded or even killed ground personnel. A burst of a vessel during launch could have resulted in the loss of the orbiter and crew. NASA changed its launch procedure of Atlantis to counter this problem and reduce any risk to personnel and orbiter.
Launch occurred on schedule at 7:38:04 p.m. EDT (23:38:04 UTC). All pre-launch processing proceeded normally, and the crew started to board Atlantis at 4:17 p.m. EDT (20:17 UTC). Crew boarding was completed at 4:58 p.m. EDT (20:58 UTC), and the hatch was closed at around 5:40 p.m. EDT (21:40 UTC). Weather was 80% go to support a launch. There were concerns due to weather at the Shuttle's TAL abort landing sites, but Istres in France changed to go in time for launch. The conditions at the other available site, Zaragoza, were observed to be improving. The third TAL site, Morón AFB, was closed for runway maintenance until June 15.
Like all of the remaining non-exigent Space Shuttle missions, launch was from pad 39A. (Pad 39B may be used for Launch-On-Need missions to rescue normal shuttle missions, particularly STS-125, which will not visit the ISS.) STS-117 was the first launch from 39A since the fateful STS-107 launch of Columbia in 2003.
Archambault, Forrester and Kotov used the SSRMS to mate the S3/S4 truss to the outboard end of the S1 truss. In a 6 hour, 15 minute spacewalk, Reilly and Olivas made final attachment of bolts, cables and connectors, and began preparations for deployment of the solar arrays. 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 successful deployment of the S4 solar arrays was the highlight of the day, adding significantly to the ISS power generation capabilities. There were continuing problems with the station's CMGs, the preferred, non-propulsive, method for controlling the station attitude. The orbiter was used for periods to control the attitude of the combined stack, and the issues appeared to have been resolved by the end of the day.
A computer malfunction on the Russian segments of the ISS occurred at 06:30 UTC and left the station without orientation control. A successful restart of the computers resulted in a false fire alarm which awakened the crew at 11:43 UTC. The P6 array was furled to a little more than half its original length. The crew enjoyed an off-duty period and Reilly and Olivas slept in Quest Airlock for spacewalk pre-breathe campout protocol.
Atlantis and ISS astronauts hauled the last bits of cargo between their two vehicles while flight controllers on Earth tested the outpost’s resuscitated Russian control and navigation computers after they crashed last week. Attitude control was switched to and from Russian command successfully, and Atlantis was given a green light for undocking on flight day 12. Expedition 15 and Atlantis's crew said goodbyes and sealed the hatches between their respective vehicles.
Atlantis did various hardware tests to prepare for a landing on June 21 and the crew had an interview with several large TV networks.
| James F. Reilly|
John D. Olivas
| June 11, |
| June 12, |
|6 hours 15 minutes||Install S3/S4 truss|
| Patrick G. Forrester|
| June 13, |
| June 14, |
|7 hours 16 minutes||Complete S3/S4 truss installation|
| James F. Reilly|
John D. Olivas
| June 15, |
| June 16, |
|7 hours 58 minutes||OMS pod thermal insulation repair, P6 array retraction|
| Patrick G. Forrester|
| June 17, |
| June 17, |
|6 hours 29 minutes||Install rotary joint for solar panels, install camera stanchion and computer network cable, secure debris shield|