STS-118

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Mission emblem
Mission emblem STS-118
Mission dates
Mission: STS-118
COSPAR-ID : 2007-035A
Crew: 7th
Begin: August 8, 2007, 10:36:42 PM  UTC
Starting place: Kennedy Space Center , LC-39A
Space station: ISS
Coupling: August 10, 2007, 18:02 UTC
Decoupling: August 19, 2007, 11:56 UTC
Duration on the ISS: 8d 17h 54min
Number of EVA : 4th
Landing: August 21, 2007, 16:32:16 UTC
Landing place: Kennedy Space Center, Lane 15
Flight duration: 12d 17h 55min 34s
(until touchdown)
Earth orbits: 201
Rotation time : 91.4 min
Apogee : 347 km
Perigee : 335 km
Covered track: 8.5 million km
Payload: S5 segment , ESP-3 , gyroscope
Team photo
v. l. No. Richard Mastracchio, Barbara Morgan, Charles Hobaugh, Scott Kelly, Tracy Caldwell, Dafydd Williams and Alvin Drew
v. l. No. Richard Mastracchio, Barbara Morgan, Charles Hobaugh, Scott Kelly, Tracy Caldwell, Dafydd Williams and Alvin Drew
◄ Before / After ►
STS-117 STS-120

STS-118 ( english S pace T ransportation S ystem) is the mission name for the 20th flight of the US space shuttle Endeavor (OV-105) of NASA . It was the 119th space shuttle mission and, after an almost five-year hiatus, the first flight of this orbiter, due to the Columbia accident in February 2003 ( STS-107 ). It was the last flight of a Spacehab module. STS-118 was launched on August 8, 2007.

team

Mission overview

The Endeavor transported the S5 carrier to the International Space Station (ISS). This lattice structure was assembled by the astronauts during an outboard mission.

Configuration of the ISS after the STS-118 mission

In addition, 2.2 tons of equipment were delivered with the Spacehab module. Conversely, 1.8 tons of unneeded equipment and completed experiments were brought back to earth.

During four exits, construction and maintenance work was carried out on the exterior of the ISS.

The new energy transmission system was used for the first time by the Endeavor. Through the SSPTS, the orbiter receives power from the space station during the coupling and can thus extend its residence time.

This mission also carried out the so-called "Teacher in Space Project", which was already planned for STS-51-L , but ended in a tragic accident due to the loss of the Challenger space shuttle . Barbara Morgan became the first teacher to teach from space.

Preparations

Shortly after the end of the Endeavor's last mission ( STS-113 ), the space shuttle was driven to the Orbiter Processing Facility on December 7, 2002 and the follow-up investigation began. The heat shield had 64 impacts, 13 of which were larger than two and a half centimeters, which is normal.

Originally, the Endeavor should have started the STS-115 mission in May 2003 , but after the Columbia disaster in February 2003, NASA decided to modernize and overhaul the space shuttle. During this Orbiter Major Modification , the Endeavor was the last orbiter to be equipped with a so-called glass cockpit from December 2003 , which replaces the three old monochrome tube screens with nine graphics-capable multifunction displays. In addition, major work was carried out on all systems of the shuttle. In addition, the new SSPTS (Station-to-Shuttle Power Transfer System) was installed, which transfers electrical energy from the space station to the Endeavor. This extends the possible coupling time by 20 percent. In addition, the TACAN landing system was replaced by the GPS system. This allows the ferry to land on any suitable runway that is 2.3 kilometers long and 40 meters wide. A total of 194 changes were made during the three-year renovation phase.

At the end of January 2007, the three main engines were installed in the Endeavor. The two OMS ( Orbital Maneuvering System ) engines followed in February . On April 6, the outer tank for STS-118, the ET-117, arrived in Florida. After initially planning to replace the storm-damaged tank from the previous mission , STS-117 , it was finally repaired and STS-118 received the tank.

Around April 10, 2007 - as with the Atlantis - all three main engines were dismantled to check for contamination. However, no such impurities were found; After another pump had been changed, all three engines were reinstalled on April 27th. From April 24th to June 12th the two solid fuel rockets (boosters) were set up; on June 17th the external tank was installed between the two boosters.

After completing the preparations and replacing a thermal insulation mat on the stern of the orbiter, the Endeavor was rolled from the Orbiter Processing Facility into the Vehicle Assembly Building on July 2nd . The next day, the Endeavor was connected to the boosters and the external tank. From July 9th to 11th, the payload canister with the Spacehab, S5 and ESP-3 was placed in the cargo bay.

The Endeavor reaches the launch pad on July 11th

In preparation for the Terminal Countdown Demonstration Test , or TCDT for short, which began the next day , the team arrived at the Kennedy Space Center (KSC) on July 16 . During this two-day exercise, the crew simulated the final hours of the countdown. In addition, the escape from the launch pad was rehearsed in a dangerous situation. The TCDT ended with a simulated abortion for the crew and the control team. Then the crew flew back to Houston.

The Endeavor on the launch pad by day ...
... and at night

The Flight Readiness Review took place on July 25th and 26th , during which it was decided that all systems are ready for take-off. In addition, the provisional start date, August 7th, has been confirmed as the first option. At the press conference that followed, William Gerstenmaier, NASA's director of space operations, said that the manufacturer of the device had acted sabotage on a computer that was to be flown to the space station on the Endeavor. The case will be investigated and the device will be repaired until it is launched.

During a regular leak test on July 29th, technicians found that either the Spacehab or the crew cabin was losing pressure. In further tests, the pressure loss turned out to be up to ten times higher than permitted. After two days, a wrongly attached supply hose was identified as the cause. On July 31, it was found that air was still escaping. One of the two pressure relief valves in the crew cabin was not working correctly - it was replaced on August 2nd with a component from the Atlantis. The subsequent print tests were all successful.

Following a conference held at KSC, NASA officials announced on August 3 that all reserve time had been used up due to the unforeseen repair work. That is why the decision was made to postpone the start to August 8th for 24 hours. This would give the technicians enough time to prepare. A few hours later the crew of seven arrived at the space center. On August 5th, all relevant sections (crew cabin, connecting tunnel, space hab) passed a four-hour pressure test.

Mission history

begin

The countdown for the mission began on August 6 at 0:00 UTC at the T-43 hour mark. Kathy Winters, who has been the USAF meteorologist in charge of shuttle launches for the past five years, said that the probability of good weather on launch day was 70 percent. Showers can only be expected occasionally. The next day, NASA announced that the probability of a shuttle launch had risen to 80 percent. Moreover telephoned Laura Bush , wife of the US president, with Barbara Morgan and wished her a good mission.

The first visible sign that the start would take place in a few hours was the swiveling back of the RSS maintenance platform (Rotating Service Structure) into its parking position. This 120 ° rotation began as planned on August 8 at 1:00 UTC and lasted 45 minutes. The three-hour filling of the large external tank began at 12:11 UTC: first with liquid hydrogen in the lower section and 40 minutes later with liquid oxygen in the upper section of the tank.

Start of the Endeavor

At 18:47 UTC the crew was driven from the crew quarters to the launch pad, where they arrived a quarter of an hour later. After taking the elevator to the 59-meter level, the astronauts were prepared to board. At 21:07 UTC, the Ice Team detected a crack in the insulating foam on the outer tank, but it was reported that this crack did not pose a threat. Later, at 20:52 UTC, a problem with the hatch's sensors was discovered while the hatch was being closed. The sensors should indicate whether the hatch is closed. At 21:20 UTC, the white room team reported that the problem with the hatch sensors had been solved and then left the launch pad. In addition, all the emergency landing sites reported good weather.

The Endeavor started as planned at 22:36 UTC under excellent weather conditions. After the three main engines had burned out, the outer tank was thrown off and photographed by the astronauts in order to discover damage. The cargo bay doors were opened later.

At a subsequent press conference, NASA's head of space operations, Bill Gerstenmaier, announced that the video recordings from the tank camera had shown that four small pieces of insulating foam had flaked off. But this happened at an uncritical point in time.

Inspection and coupling

On the second day of flight (August 9) , the heat shield was checked , as has been the case since STS-114 . For this purpose, the OBSS inspection arm was attached to the robotic arm of the orbiter and the particularly endangered areas were then examined. One after the other, the right wing, the nose and the left wing were scanned.

During the day, NASA announced that when the Endeavor started, a total of nine pieces of foam came off the outer tank. An initial film and photo analysis showed that only three parts hit the ferry. However, there would be no evidence of damage. The three fragments hit the orbiter 24, 58 and 173 seconds after launch. But all parts were so small that they could not cause any serious damage.

The Endeavor is approaching the ISS

After a two-day pursuit, the Endeavor caught up with the ISS on August 10 (3rd day of flight) and docked at 18:02 UTC. Previously, the 43-year-old shuttle commander Scott Kelly had positioned the US space shuttle 180 meters from the space station. While both spaceships flew over the Atlantic, the Endeavor carried out the obligatory “somersault backward maneuver”. The ISS crew used these ten minutes to photograph the entire underside of the orbiter with high-resolution cameras in order to uncover possible minor damage to the heat shield.

While the leak tests were in progress, mission specialist Tracy Caldwell activated the orbiter's robotic arm and lifted the S5 element out of the cargo bay. After the hatches were opened two hours after arrival and the two crews had greeted each other, S5 was handed over to the ISS robotic arm , which kept it until assembly the next day.

At 21:17 UTC, the new SSPTS ( Station-to-Shuttle Power Transfer System ) was successfully put into operation for the first time. The SSPTS developed by Boeing over the past four years enables the orbiter to draw power from the ISS. This means that a connected ferry can reduce its consumption of limited supplies of water and oxygen, which the fuel cells need to generate electricity, to a minimum, thus increasing the coupling time by up to four days. For NASA, the use of the SSPTS means that the shuttle astronauts can work longer at the station and that the remaining construction flights of the US space shuttles can be used optimally. The SSPTS regulates the 120 volts of the ISS down to the 28 volts of the orbiter. The ferry can draw a maximum of eight kilowatts from the space station.

Mission specialists Rick Mastracchio and Dave Williams went to the Quest airlock at the end of the day and stayed overnight. During this so-called campout, they breathed pure, low-pressure oxygen to prepare for their first EVA the following day.

A tile is damaged near the door of the right main landing gear (right edge of the picture)

As NASA announced on the same day, the first evaluation of the close-up images transmitted to Earth would have provided indications of possible damage to the underside of the orbiter. A white furrow was discovered near the door of the right main landing gear. This stands out clearly from the other black tiles and is nine by six centimeters in size. The spot is one and a half meters behind the door and may be due to a piece of ice that detached from the fuel tank during the ascent and hit the Endeavor 58 seconds after take-off. The astronauts were instructed to use the OBSS to examine the site thoroughly on August 12.

Working on the ISS

Rick Mastracchio works on the ISS

The fourth day of flight (August 11) was dominated by the first EVA of this mission, which began at 16:28 UTC. Rick Mastracchio and his Canadian colleague Dave Williams installed the S5 segment on the starboard side of the station. So that the astronauts could work in peace, the solar cell surfaces of the S4 module were blocked for the duration of the work. In addition, the radiator was retracted and secured by P6 in order to bring the module to its final place during the next mission ( STS-120 ). After 6 hours and 17 minutes, the excursion ended at 22:45 UTC.

For reasons that were initially unknown, the main computer in the US part of the station failed during this EVA - similar to the previous mission. The replacement computer immediately took over the task of the C&C computer (Command and Control). The third computer in the system, which had been in wait mode until then, was "activated" and set up as a new backup computer. A few hours later, the main unit was able to be started again. The problem was caused by an incorrect command.

August 12th (fifth day of flight) was devoted to a new inspection of the heat shield - referred to by NASA as "Focused Inspection". In total, Tracy Caldwell and Barbara Morgan, together with Scott Kelly, examined five areas of the heat shield that the engineers did not classify as clearly safe. Apart from one damage, all areas could be classified as safe. In addition, the Russian on-board computer, which had failed during the last mission, was replaced. The fourth and last voltage converter of the SSPTS was also activated for the first time. Like the other three, it worked perfectly. Therefore, the extension of the mission by three days and a fourth exit could be approved afterwards.

The crew loaded supplies from the Spacehab into the ISS throughout the day. In the evening Richard Mastracchio and Dafydd Williams went to the Quest airlock and carried out their second campout.

The second dropout took place on the sixth mission day, August 13th. Mastracchio and Williams exchanged a gyroscope that is used to control the station's position. The defective device, which had failed a year earlier, was attached to the ESP-2 platform and was supposed to be brought to earth with one of the next shuttle missions. In addition, the location was prepared where the ESP-3 platform was assembled the following day. The EVA lasted 6 hours and 28 minutes and ended on schedule at 22:00 UTC.

Meanwhile, work on the Russian computer and transport activities continued in the station. The newly installed gyroscope was started up overnight, it works perfectly.

The ESP-3 platform is transferred from the shuttle arm to the station arm

The seventh day of flight (August 14) saw the installation of ESP-3 . It was lifted out of the orbiter's loading bay with the Canadarm of the Space Shuttle and transferred to the Canadarm2 of the space station. This then attached the element to the lattice structure P3. No external action was necessary for this. In addition, the module circled Zarya for the 50,000 on that day. Times the earth.

In addition, Barbara Morgan gave a lesson lasting about 30 minutes. She answered questions asked by students at the Discovery Center of Idaho in the US state of Idaho. Two more lessons were planned. Tracy Caldwell also celebrated her 38th birthday. Mastracchio and ISS expedition 15 member Clay Anderson then went into the airlock to conduct a campout.

Rick Mastracchio's spacesuit glove is damaged

On the eighth day of the flight (August 15), the third spacecraft was on the program. Mastracchio and Clay Anderson began their exit at 14:37 UTC. The two astronauts were preparing to move P6, which was scheduled for the next mission (STS-120). During the EVA, an SASA antenna (S-Band Antenna Structural Assembly) was moved from P6 to P1 and a transponder was removed. In addition, the two drove the CETA platforms from the port to the starboard side of the ISS. Both “dropouts” got along very well with their tasks and were soon ahead of their work schedule. Around 18:55 UTC, NASA announced that the EVA had to be canceled because of a tear in the upper layer of Mastracchio's glove. He then returned to the airlock to connect to the station's life support systems to be on the safe side, while Anderson continued to work for an hour. At 20:05 UTC they jointly completed the 5 hour and 28 minute long exit. Except for the dismantling of the MISSE experiment, all tasks could be completed. The cause of the crack in Mastracchio's glove was identified as a sharp edge on an ISS component after landing.

On the ninth day of the flight (August 16), Barbara Morgan's second lesson took place, which she held together with Alvin Drew . This time, Morgan spoke to students at the Challenger Center for Space Science Education in Alexandria, Virginia . Later she also spoke to students in the McCall-Donnelly school district in Idaho via amateur radio ( ARISS project) after problems and a resulting delay .

NASA also announced that shortly after getting up, the astronauts discovered a small damage to one of the cockpit windows. During the sleep period, the outer pane of one of the commander's windows on the left side of the Endeavor had been hit by a tiny piece of space debris or a micrometeorite. After the photos of the one millimeter deep impact were checked by technicians, NASA said that the crew was not endangered and that the mission would continue.

The rest of the day was used to prepare for the fourth exit and for transfer tasks. In addition, for the first time on the mission, the astronauts had a longer period of free time.

Hurricane Dean photographed from the ISS

August 17th (tenth day of the flight) was marked by transfer tasks, press conferences and preparations for the mission's last exit. During the course of the day, NASA announced that it would probably land the Endeavor on August 21, one day earlier than planned. The reason for this is Hurricane Dean , which could possibly make it necessary to close the flight control center for a few days.

At the beginning of the eleventh day of flight (August 18), NASA announced that the fourth EVA had been cut by two to four and a half hours. This makes it possible to close the hatches between the shuttle and the ISS immediately after the EVA and to undock on the twelfth day of the mission.

During the fourth field assignment, Dave Williams and Clay Anderson installed an antenna and successfully tightened four screws of a clamp on an S-band antenna already attached to the Z1 segment. In addition, a holder for the OBSS inspection arm was attached to the top of the S1 segment so that it can be deposited there at the end of the STS-123 mission (the volume of the payload on the subsequent STS-124 mission was too large to take the OBSS with you). In addition, the MISSE experiment was recovered and stowed in the Endeavor to return to Earth. The exit, which NASA had already planned in advance in the event of a mission extension, took 5 hours and 2 minutes. Because of the two-hour shortening, the final attachment of some protective shields against micrometeorites had to be postponed. These sheets had to be removed by Unity and Destiny during the STS-117 mission in order to install a hydrogen valve, but could no longer be properly attached. Since then, they have only been temporarily locked in place with straps and should be screwed down when you get out later.

Because the hatches were due to be closed on the same day, the traditional farewell ceremony for the ten space travelers was only canceled for a short time around 20:45 UTC. 25 minutes later, at 21:10 UTC, the hatch to the ISS was locked.

return

After disconnecting: the ISS taken from the Endeavor

After undocking on August 19 (twelfth day of flight) at 11:56 UTC, the Endeavor departed from the ISS without flying around it again. This gave the crew some free time. The crew then carried out a final check of the heat shield. With the OBSS, the areas that were particularly stressed during the landing were scanned for several hours.

NASA announced that they only wanted to use the two landing options for Florida on August 21. Hurricane Dean is approaching Mexico, which is why there is no danger of having to evacuate flight control in Texas. This reduced the time pressure to have to land on the 14th day of the flight if possible.

On the 13th day of the flight (August 20), preparations for the landing began. In the evening Houston was able to give the green light for landing - the evaluation of the OBSS data had shown no signs of further damage to the heat shield. It was decided not to use the landing facilities in Edwards. Nevertheless, the base was manned in the event of a possible change in the weather in order to provide an alternative.

The Endeavor touches down

The 14th and final day of the flight (August 21st) began with the locking of the spacehab and the stowing away of the objects that were not important for the landing. At 15:07 UTC the control center informed the crew that they wanted to use the first landing opportunity at KSC during orbit 201. The landing maneuver was initiated at 15:25 UTC with the brake ignition of the two OMS engines. At 16:32 UTC the Endeavor touched down on the Shuttle Landing Facility of the Kennedy Space Center in Florida.

After the crew had left the orbiter and underwent an initial medical examination, six of the seven astronauts examined the outer skin of the Endeavor about an hour after landing. The only exception was Barbara Morgan, who still had problems with her sense of balance . The damage to the heat protection tile damaged during take-off had hardly increased during the landing.

After the final work, the Endeavor was towed to the Orbiter Processing Facility, where it was prepared for its next space flight (STS-123).

During the follow-up inspection of the orbiter, it was found that the Endeavor was hit by a micrometeorite not just on one of the cockpit windows during the flight: a week after landing, technicians discovered two impacts on the radiators in the cargo hold doors. The latter were not damaged. The Atlantis suffered similar damage when it returned from its STS-115 mission a year earlier.

Damage to the heat shield

Close up of the damaged tiles

During take-off, several pieces of foam broke off on the outer tank, causing damage to the heat shield. During the so-called Focused Inspections on the fifth day of the flight (August 12), a closer examination was carried out to determine how deep the impact had damaged the 19 square centimeter area and whether repairs were necessary. The detailed images showed that the damage reached down to the aluminum structure of the orbiter. A small area two and a half centimeters long and half a centimeter wide was exposed.

The image evaluations had also shown that the impact was caused by insulating foam and not ice, as initially assumed. A piece the size of an apple had detached itself from a fuel line in the outer tank, collided with a strut, shattered into several pieces and finally hit the Endeavor.

The damage after landing

On August 19, NASA announced that it had decided not to repair the Endeavor and land despite the damage. This decision was preceded by days of tests and analyzes on the ground. With the help of the laser data from the OBSS scan, it was possible to create a three-dimensional replica of the damaged heat shield area. The 3-D tile model went through several test series in the plasma laboratory of the Johnson Space Center. In addition, engineers at the Ames Research Center used computer programs to test the effects of the plasma on re-entry on the damaged tile area. The results were verified by technicians from the Langley Research Center .

The damage had hardly increased during re-entry. The structure of the orbiter was also not damaged.

See also

Web links

Commons : STS-118  - Album with pictures, videos and audio files

swell

  1. ↑ NASA: Space Shuttle Endeavor Moves to Launch Pad , July 11, 2007 (English)
  2. ↑ NASA: NASA Gives 'Go' for Shuttle Endeavor Launch on Aug. 7 , July 26, 2007 (English)
  3. ↑ Florida Today: Sabotage won't delay Endeavor flight ( Memento from December 30, 2015 in the Internet Archive ), July 27, 2007 (English)
  4. ↑ Florida Today: Leak not yet a threat to launch ( Memento of September 27, 2007 in the Internet Archive ), August 1, 2007 (English)
  5. ↑ NASA: NASA's Space Shuttle Mission Postponed 24 Hours , August 3, 2007 (English)
  6. ↑ NASA: NASA's Shuttle Endeavor Begins Mission to the Space Station , August 8, 2007 (English)
  7. ↑ SPACE.com: Shuttle's Foam Debris Hits 'Underwhelming,' NASA Says , August 9, 2007 (English)
  8. ↑ Boeing: Station-Shuttle Power Transfer System ( Memento from July 6, 2009 in the Internet Archive ) (English) from 2007, accessed from the web archive on May 19, 2017.
  9. ↑ NASA: STS-118 MCC Status Report # 07 , August 11, 2007 (English)
  10. ↑ NASA: STS-118 MCC Status Report # 11 , August 13, 2007 (English)
  11. ↑ NASA: STS-118 Education Resources NASA page on teaching from space
  12. ↑ NASASpaceflight.com: EVA-3 terminated due to Mastracchio glove damage , August 15, 2007 (English)
  13. ↑ NASASpaceflight.com: Mastracchio's glove damage cause revealed , August 31, 2007 (English)
  14. ↑ NASA: Barbara Morgan Talks With Students on Ham Radio , August 16, 2007 (English)
  15. ↑ NASA: STS-118 MCC Status Report # 21 , August 18, 2007 (English)
  16. ↑ NASA: STS-118 Landing Ground Tracks , August 19, 2007 (English)
  17. ↑ NASA: Shuttle Endeavor Crew Returns Home After Successful Mission , August 21, 2007 (English)
  18. ↑ NASA: Space Shuttle Processing Status Report , August 31, 2007 (English)
  19. ↑ Florida Today: Tile ding worse than expected, August 13, 2007 ( September 30, 2007 memento in the Internet Archive ), accessed May 19, 2017.
This article was added to the list of excellent articles on September 19, 2007 in this version .