STS-122

STS -122 (English Space Transportation System) is the designation for a flight mission of the American Space Shuttle. It was the 121st shuttle mission and the 29th flight of the Space Shuttle Atlantis. The 24th flight of a space shuttle to the International Space Station (ISS) was held to 20 February 2008 of 7.

• 3.1 Sensor problems during the first attempts to start the
• 3.2 refueling test

• 4.1 Start
• 4.2 Inspection and coupling
• 4.3 Working on the ISS
• 4.4 return

Team

Shuttle crew

• Stephen Frick ( second space flight ), commander of United States
• Alan Poindexter ( first space flight), Pilot United States
• Stanley Love ( first space flight), Mission Specialist United States
• Rex Walheim ( second space flight), Mission Specialist United States
• Leland Melvin ( first space flight), Mission Specialist United States
• Hans Schlegel ( second space flight), Mission Specialist ( ESA) Germany

ISS crew Departure

ISS Expedition 16

• Léopold Eyharts ( second space flight), flight engineer (ESA ) France

ISS Crew Return

ISS Expedition 16

• Daniel Tani ( second space flight), flight engineer United States

Mission overview

STS -122 brought Columbus to the main contribution of ESA to the International Space Station. With this, the European research module was connected during a space exit.

In addition, a nitrogen tank was replaced and transported equipment and consumables to the station.

Preparations

After the landing of STS -117 on 22 June 2007 at Edwards Air Force Base, the Atlantis was flown back to Kennedy Space Center (KSC ), where she arrived on July 3. A day later, the space shuttle has been moved to the Orbiter Processing Facility (OPF ). There she was prepared for their next use.

On September 14, the outer tank of the mission at KSC arrived and was taken to the Vehicle Assembly Building ( VAB). There he was checked and prepared for launch.

Due to the delays in the previous mission (STS -120) was feared that this would also have implications for STS -122. Due to renovations to the outskirts of the VAB was for a long time only a mounting bay available. This would have meant to the launch structure only can begin after the Discovery had left the VAB. The starting period in December was only a week. Therefore, NASA accelerated the work on the gates, so that on September 20, could drive a launch platform for the Atlantis in the VAB and so were no delays in STS -122.

The structure of the two solid rocket began on September 26 and was completed on October 14. During this time, the previously disassembled main engines were installed back in the orbiter. The external tank was connected on 19 October with the boosters.

The transport of Atlantis from the OPF to the VAB was held on November 3. In the orbiter is interconnected to the outer tank and the boosters. A week later, on November 10, was the six-hour rollout to the launch pad 39A. The next day was the Columbus module, which had been already transported on November 7 in the payload container to the ramp, loaded into the cargo bay of Atlantis.

On 19 and 20 November, the astronauts completed the so-called Terminal Countdown Demonstration Test. This TCDT exercise played through the final hours of the countdown to give the team the opportunity to familiarize yourself with the processes. The TCDT ended with a simulated launch abort.

The Special Air decrease was held on 30 November at KSC. The NASA managers discussed the launch readiness of all systems of the Space Shuttle. Unanimously told the panel that STS -122 is ready to start. Simultaneously, the provisional start date has been confirmed with the 6th of December.

On 4 December, the countdown began for the mission. A few hours before the team arrived at KSC.

Sensor problems during the first attempts to start the

On 6 December 2007 the first launch attempt was made. The filling of the outer tank began around 12:00 UTC. Shortly after that was a problem with the ECO sensors ( engine cutoff sensor, low - level of switching off ) was observed. Two of the four fuel sensors were not working. The launch attempt was canceled at 14:57 UTC, after which the external tank was emptied again. NASA analyzed the problem that had been carried out at the STS- 114, and STS -115 to a shift of the start. After these incidents, the wires have been revised and it was believed that the problem was solved. First, a shift of 24 hours announced (7 December 2007 at 21:09 UTC). Later on, the start was moved at 20:21 UTC by two more days on the 9th of December. However, the starting rules were tightened - it should all four ECO sensors are working properly during the countdown.

Shortly after the start of refueling on December 9 had one of the ECO sensors were added to a malfunction. Therefore, the launch attempt was called off at 12:24 UTC. After further investigation, the tank was emptied. Later, NASA announced that the launch should take place no earlier than January 2, 2008 in order to have more time for a more detailed investigation of the problem with the ECO sensors.

The crew members flew on December 10 back to the Johnson Space Center in Houston to undergo additional training hours and to be able to spend Christmas with their families. According to Wayne Hale, manager of the shuttle program, there is a possibility that no flight of the shuttle program was carried out with properly functioning ECO sensors.

On 13 December, the launch was postponed again by eight days on 10 January. Wayne Hale, according to one wanted to allow technicians to spend more time with their families.

Refueling test

To get the strange behavior of the sensors on the track, led by NASA on December 18, a tank test. To this end, the wiring of the ECO sensors between the external tank and the orbiter was associated with additional diagnostic equipment. The analysis of data from the start attempts on 6 and 9 December had shown that the cause is to be sought in the sensors themselves, but probably in the wiring harnesses that run from the tank to an electronics unit in the back of the ferry. During the filling, in which two sensors failed, the electrical resistance in each cable was measured accurately. It could be found at which point the line system was defective. Wayne Hale said after the test that the cause of the false ECO sensors ads actually lies in the wiring. By fueling with liquid hydrogen, the grommet can be forgiven in the outer wall of the tank so that the electronic contact between the cable terminals and implementation could be affected.

Before the Christmas holidays has begun to remove insulating foam at the relevant point on the tank. On 27 December, NASA announced that it would remove the cable entry and for further investigation to send Marshall Space Flight Center. Furthermore, we prepared a replacement unit for installation, in which the connections were soldered to the outer wall directly to the strands of the cable to the onboard electronics. The further procedure depends on the results. Therefore, for the time being no new start date was mentioned. On January 3, it was announced that the new implementation on January 10 will be built and is expected to start at the earliest on 24 January. According to John Shannon, deputy head of the shuttle program, a start date in the first week of February is more likely.

NASA announced on 11 January that has been set as the new launch date of February 7. Previously, Russia had brought forward the start of the next Progress freighter to two days on the 5th of February. This ensures that no two spaceships arrive simultaneously at the space station. The appointment was confirmed by another Flight Readiness Review on January 30, however, one observes a further problem with the radiators. A transfer line is apparently age weaknesses, which are examined, however, one could fix the problem.

Mission History

Start

Shortly after the crew arrived at KSC on February 4, the countdown began at 22:00 UTC. Due to bad weather, NASA assumed a probability of only 30 percent, that the weather on February 7, allows a start.

On 7 February from 00:20 UTC to the RSS work platform from the Atlantis was swung away. Later, at 10:30 UTC began filling the external tank. After that, the ECO sensors were tested which worked perfectly. The weather paved the teams continue to worry. So it was in 13 kilometer distance to the Kennedy Space Center rain. The start is only allowed as long as the radius of 30 kilometers no rain falls. The clouds did not meet the acceptable weather criteria. Later, however, the start probability increased to 40 percent.

The crew arrived at 16:15 UTC on the launch pad. Then the weather improved rapidly and Atlantis was around 19:45:30 UTC stand out from the launch pad 39A, exactly seven years after the shuttle STS -98 was launched with the Destiny laboratory module to the ISS. After two minutes after the start, the two boosters were jettisoned was at 19:54 UTC, the shutdown of the main engines and the separation of the outer tank.

Inspection and coupling

On the second flight day (February 8 ), the heat shield was checked using the Orbiter Boom Sensor System. This was previously connected to the robotic arm of the shuttles. Among other things, the wings and the nose were sampled. Furthermore, preparations were made for the docking with the space station and checked the equipment for spacewalks.

On the third day of flying (9 February ), the Atlantis had reached the ISS. Before docking, the Atlantis resulted from the so-called Rendezvous Pitch Maneuver. This complete rotation about the pitch axis gave the ISS crew the opportunity to photograph the heat shield of the orbiter. Particular attention was paid to the right OMS pod, in which, similar to STS -117, had solved a heat protection mat.

At 17:17 UTC was the connection to the space station. It was the first time that a shuttle on the Harmony module docked. After the surge, the hatches between the ISS and Space Shuttle were opened at 18:40 UTC and the crews greeted each other. After equipment for the three EVAs were brought into the Quest airlock.

A little later it was announced that the first spacewalk (EVA ) is shifted by one day and performed by Stan Love, Hans Schlegel held together with Rex Walheim. This was due to striking body measurements with Hans Schlegel. Simultaneously with the EVA shift the Atlantis mission was extended by one day. The replacement of the Soyuz seats was preferred, so Dan Tani is now part of STS -122 and Expedition 16 to the Léopold Eyharts

Work on the ISS

After the wake-up call on the fourth mission day turned out that in Schlegel there is no health problem. Schlegel received after the release of the second spacewalk participate. After the displacement of the spacewalk of the flight day (10 February ) was rescheduled at short notice. Thus, the cargo transfer operations were carried out and scheduled a closer inspection of the heat protection mat. In addition, the preparations for the exit that have been canceled the day before, were continued. In the evening, Rex Walheim and Stanley Love went for a " campout " in the Quest airlock.

On February 11, at 14:13 UTC Rex Walheim and Stanley Love began scheduled for six and a half hours the first of three spacewalks. Here, a coupling adapter was attached to Columbus, to heave the laboratory using the ISS robotic arm from the hold of the ferry can. Then they prepared the nitrogen tank on his replacement at the second EVA. At the same time Columbus was lifted from the cargo bay and placed in position on the starboard docking port on the Harmony. There the module at 21:44 UTC was mounted by the two " outs ". The withdrawal ended after seven hours and 58 minutes around 22:11 UTC.

The February 12 was mainly the internal structure of Columbus. First, a pressure tightness test was performed later at 14:08 UTC, the hatches were opened to Columbus. Immediately after the module was connected to the circuit of the station, turned on the light and ventilation active. Also found transfer activities, preparations take place on the next exit and several interviews.

The second spacewalk began on 13 February at 14:27 UTC. The aim of the conducted by Walheim and Schlegel exit was the substitution of the P1 nitrogen tank, which is part of the cooling system of the station. Since this work was done very quickly, two more tasks could be performed. So shipping brackets were covered at Columbus and inspected the debris shield on Destiny. This was the second German Schlegel conducted by Thomas Reiter of an EVA. The withdrawal ended at 21:12 UTC, after six hours and 45 minutes. The mission was again extended by one day.

On February 14, preparations were made on the third spacewalk the next day. It further found instead of cargo transfer tasks. In addition, German Chancellor Angela Merkel, ESA Director General Jean -Jacques Dordain and Thomas Reiter Hans Schlegel with Dan Tani, Peggy Whitson, Yuri Malenchenko and Léopold Eyharts phoned. In the evening, Walheim and Love went for a campout in the Quest airlock.

The third outdoor use two external payloads were attached to Columbus on February 15. The astronauts Walheim and Love began their seven and a half hour mission at 13:07 UTC. In addition to the installation of solar and EuTEF the defective CMG control gyro ( Control Moment Gyroscope ) was stowed for return to Earth in the cargo bay of Atlantis. The CMG had failed in October 2006 and was during STS -118 in August 2007, replaced by a spare part. Then they examined a defective handle on Quest, which is probably the cause of damage to the astronauts gloves. The withdrawal ended at 20:32 UTC.

On February 17, first cargo transfers took place. After that, the two crews adopted each other. At about 17:30 UTC, the hatches between the space station and Atlantis were closed.

Return

On February 18, at 9:24 UTC, the separation of the two spacecraft occurred. After undocking, the Atlantis flew around the ISS and made photo - and video recordings of the current configuration. During the day, once again, the heat shield was checked.

On 20 February, the flight line at 12:32 UTC decided to use the first of the four landing opportunities of the day. Half an hour later the brake ignition was to leave Earth orbit. After 202 orbits put the space shuttle at 14:07:10 UTC with the main landing gear on the web 15 of the Shuttle Landing Facility at KSC.

After cooling the orbiter and various tests the crew about 45 minutes increased after landing into a crew van, which was moved in front of the hatch. At 15:45 UTC the team left this, to look at the external condition of the space shuttle. Just Flight Engineer Daniel Tani remained in the van, as he in weightlessness, again had to get used to the pull of gravity after four months as part of the ISS Expedition 16.

A few hours later, the Atlantis was towed into the Orbiter Processing Facility, to prepare them for the Hubble Servicing Mission STS -125.