STS-122

STS-122 was a NASA Space Shuttle mission to the International Space Station, flown by the. STS-122 marked the 24th shuttle mission to the ISS, and the 121st Space Shuttle flight overall.
The mission was also referred to as ISS-1E by the ISS program. The primary objective of STS-122 was to deliver the European Columbus science laboratory, built by the European Space Agency, to the station. It also returned Expedition 16 Flight Engineer Daniel M. Tani to Earth. Tani was replaced on Expedition 16 by Léopold Eyharts, a French Flight Engineer representing ESA. After Atlantis landing, the orbiter was prepared for STS-125, the final servicing mission for the Hubble Space Telescope.
The original target launch date for STS-122 was December 6, 2007, but due to engine cutoff sensor reading errors, the launch was postponed to December 9, 2007. During the second launch attempt, the sensors failed again, and the launch was halted. A tanking test on December 18, 2007, revealed the probable cause to lie with a connector between the external tank and the shuttle. The connector was replaced and the shuttle launched during the third attempt on February 7, 2008.

Crew

Mission payloads

STS-122 was the ISS Assembly Flight 1E, which delivered the European Columbus laboratory module to the station, along with the Biolab, Fluid Science Laboratory, European Drawer Rack, and European Physiology Modules payloads.
STS-122 also carried the Solar Monitoring Observatory, the European Technology Exposure Facility, and a new Nitrogen Tank Assembly, mounted in the cargo bay of an ICC-Lite payload rack, as well as a spare Drive Lock Assembly sent to orbit in support of possible repairs to the starboard Solar Alpha Rotary Joint, which was malfunctioning.
Several items were returned with Atlantis: A malfunctioning Control Moment Gyroscope that was swapped out with a new one during STS-118, and the empty Nitrogen Tank Assembly was placed in the orbiter's payload bay, along with a trundle bearing from the Starboard SARJ that was removed during an EVA performed by Expedition 16.

Location	Cargo	Mass
Bay 1–2	Orbiter Docking System EMU 3015 / EMU 3017	~
Bay 3P	Shuttle Power Distribution Unit	~
Bay 5P	Power/Data Grapple Fixture for Columbus
Bay 6	ICC-LITE with EUTEF, SOLAR, NTA
Bay 7P	ECSH on APC	~
Bay 8–12	Columbus Orbital Facility
Starboard Sill	Orbiter Boom Sensor System	~
Port Sill	Canadarm	~
	Total:

Outreach

Stowed within the Official Flight Kit, Atlantis carried three green starting flags provided by NASCAR in recognition of the 50th running of the Daytona 500 on February 17, 2008, and the 50th anniversary of NASA on October 1, 2008. Once returned to Earth, one of the flown flags will be placed on public display at the Daytona International Speedway in Florida, one will be presented to Ryan Newman, the winner of the 2008 Daytona 500, and the third will be used by NASA as part of its anniversary activities.

Crew seat assignments

Mission background

The mission marks:

152nd NASA crewed spaceflight.
121st Space Shuttle flight since STS-1.
29th flight of Atlantis
96th post-Challenger mission.
8th post-Columbia mission.
8th visit to the International Space Station for Atlantis.
300th US astronaut in space.
Shuttle processing

Launch preparations

The external tank arrived at the Kennedy Space Center on September 14, 2007, after traveling by barge from the Michoud Assembly Facility in Louisiana. The external tank was then transferred to the Vehicle Assembly Building to be inspected, and have the liquid oxygen feedline bracket modified, before being mated to the solid rocket boosters on October 17, 2007.
The external tank was attached to the solid rocket boosters on October 18, 2007, and Atlantis moved to the VAB on November 3, 2007. With the entire stack placed upon the mobile launcher platform, Atlantis moved to launch pad 39A on November 10, 2007, and the Columbus module was loaded into the orbiter's payload bay on November 12. The terminal countdown demonstration test was completed on November 20, 2007.
Following the final Flight Readiness Review on November 30, 2007, NASA managers announced that Atlantis was ready to fly, and the launch date of December 6, 2007, was confirmed. The crew arrived at Kennedy Space Center on December 3, 2007, to prepare for the first launch attempt on December 6, 2007.

December 6 (launch attempt 1)

On Thursday, December 6, 2007, 16 minutes into the loading of the liquid hydrogen and liquid oxygen into the external tank, two of the four liquid hydrogen engine cutoff sensors failed to respond correctly, resulting in Launch Director Doug Lyons deciding to postpone the launch. The fuel cutoff sensor system is one of a series of redundant systems that protect the shuttle's main engines, by triggering engine shutdown if fuel runs unexpectedly low. The Launch Commit Criteria require that three of the four sensor systems function properly prior to liftoff. The scheduled launch time was tentatively postponed 48 hours to December 8, 2007, at 15:43 EST.
On December 7, 2007, managers evaluated the options to fly, under the flight rationale guidelines. The issue was thought to be in the wiring inside the external tank, that results in the ECO sensors reporting incorrectly. During loading, testing of the ECO sensors is done to ensure they function properly, but when the "dry tank" command was sent, the third and fourth sensors continued to report "wet" conditions. The concern was that if the tank were about to run dry, the sensors that control the shutdown of the shuttle's main engines might not send the shutdown command, resulting in running the engines without fuel, a dangerous situation. Managers evaluated if the Launch Commit Criteria could be removed, allowing Atlantis to fly with two of four sensors, and augment the LCO system with on-ground monitoring of propellant use by the Flight Control staff. The other option would involve repair or replacement of the sensors, which would most likely require the orbiter be moved back into the Vehicle Assembly Building, and would rule out a December launch.
Following the Mission Management Team meeting on December 7, 2007, Shuttle Program Director Wayne Hale explained during the press briefing that the team had discussed the issues at length, and had tentatively decided to attempt a Sunday launch. The Launch Commit Criteria would be changed, and Flight Controller procedures would be finalized to allow for additional monitoring of the ECO system during ascent. One of the changes to the LCC will be the requirement that during tanking, all four sensors must be operational. In the past, when this system has failed during the initial launch attempt, all four sensors performed normally during the next attempt. If this were the case for Sunday's launch attempt, it would be consistent with what has been seen in the past. If the sensors fail during re-tanking on December 9, 2007, this would indicate that the issue is not consistent with the evidence seen in the past. Managers would hold an MMT meeting on December 8, 2007, to further discuss this rationale, and the Flight Controller procedures, before making a final decision.
On December 8, 2007, the Mission Management Team met to finalize plans for the Sunday launch, and discuss possible launch options. There was a unanimous decision to attempt a Sunday launch using the modified Launch Commit Criteria. The modified criteria require all four ECO sensors to function normally during tanking, include the implementation of a Flight Controller procedure to continue monitoring the ECO sensors after liftoff during ascent, and shorten the launch window from five minutes to one minute to conserve fuel. Those changes would be done only for the launch of STS-122, and are not permanent changes. Should any of the sensors give errors during tanking, the launch attempt would be scrubbed. Following STS-122, Space Shuttle Program Director Wayne Hale and Mission Management Team Chairman LeRoy Cain explained that there would be a variety of activities and procedures put into effect to address the ECO issues. A multi-center troubleshooting team would be convened, and changes to the main engines would be performed, to improve the way the engines use and control the liquid hydrogen reserves, including upgrades to the flow meters inside the engines.

December 9 (Launch attempt 2)

Fueling of Atlantis began at 05:55 EST. During fueling at 06:52 EST, the third ECO sensor failed wet, violating the modified Launch Commit Criteria that required all four sensors to function properly. The launch was officially scrubbed at 07:25 EST. Troubleshooting the problem would rule out a December launch. NASA finally gave a new launch date of January 10, 2008.
During the post-scrub news conference, Launch Director Doug Lyons said that a rollback to the Vehicle Assembly Building was not a situation managers were considering currently, and explained that the pad offers extensive access to the systems for troubleshooting and investigation. "We can do extensive troubleshooting out there before we would entertain rolling back. There's not many things we can't do out at the launch pad that we could do in the VAB." Managers have convened a short-term troubleshooting team to design a plan to identify, and hopefully predict, or prevent the ECO anomaly.