CAPE CANAVERAL, Fla. – On Launch Pad 39A at NASA's Kennedy Space Center in Florida, STS-127 Mission Specialist Julie Payette gets into the slidewire basket that is part of emergency exit equipment. She and other crew members are learning about emergency procedures from the launch pad. The crew is at Kennedy for a launch dress rehearsal called the terminal countdown demonstration test, or TCDT, which includes emergency exit training and equipment familiarization. Endeavour's STS-127 mission is the final of three flights dedicated to the assembly of the Japanese Kibo laboratory complex on the International Space Station. Endeavour's launch is targeted for June 13. Photo credit: NASA/Kim Shiflett

CAPE CANAVERAL, Fla. – On Launch Pad 39A at NASA's Kennedy Space Center in Florida, STS-127 crew members listen to instructions about emergency exit from the shuttle. The astronauts are, clockwise from left, Mission Specialist Julie Payette, Pilot Doug Hurley, Mission Specialists Christopher Cassidy and Tim Kopra, and Commander Mark Polansky. At far right is Mission Specialist Dave Wolf. Payette represents the Canadian Space Agency. The crew is at Kennedy for a launch dress rehearsal called the terminal countdown demonstration test, or TCDT, which includes emergency exit training and equipment familiarization. Endeavour's STS-127 mission is the final of three flights dedicated to the assembly of the Japanese Kibo laboratory complex on the International Space Station. Endeavour's launch is targeted for June 13. Photo credit: NASA/Kim Shiflett

CAPE CANAVERAL, Fla. – On Launch Pad 39A at NASA's Kennedy Space Center in Florida, STS-127 crew members listen to instructions about emergency exit from the shuttle. Standing from left to right are Commander Mark Polansky, Mission Specialists Tom Marshburn, Christopher Cassidy, Tim Kopra and Julie Payette, and Pilot Doug Hurley. The crew is at Kennedy for a launch dress rehearsal called the terminal countdown demonstration test, or TCDT, which includes emergency exit training and equipment familiarization. Endeavour's STS-127 mission is the final of three flights dedicated to the assembly of the Japanese Kibo laboratory complex on the International Space Station. Endeavour's launch is targeted for June 13. Photo credit: NASA/Kim Shiflett

CAPE CANAVERAL, Fla. – At the slidewire basket landing area near Launch Pad 39A at NASA's Kennedy Space Center in Florida, STS-127 Mission Specialist Dave Wolf practices getting out of a basket, which are used for emergency exits from the pad. At far left is Mission Specialist Tim Kopra. Hold the basket steady is Mission Specialist Tom Marshburn. The crew is at Kennedy for a launch dress rehearsal called the terminal countdown demonstration test, or TCDT, which includes emergency exit training and equipment familiarization. Endeavour's STS-127 mission is the final of three flights dedicated to the assembly of the Japanese Kibo laboratory complex on the International Space Station. Endeavour's launch is targeted for June 13. Photo credit: NASA/Kim Shiflett

CAPE CANAVERAL, Fla. – On Launch Pad 39A at NASA's Kennedy Space Center in Florida, STS-127 crew members listen to instructions about emergency exit from the shuttle. Standing left to right are Mission Specialist Julie Payette, Commander Mark Polansky (behind Payette), Mission Specialists Tim Kopra, Dave Wolf and Tom Marshburn. Payette represents the Canadian Space Agency. The crew is at Kennedy for a launch dress rehearsal called the terminal countdown demonstration test, or TCDT, which includes emergency exit training and equipment familiarization. Endeavour's STS-127 mission is the final of three flights dedicated to the assembly of the Japanese Kibo laboratory complex on the International Space Station. Endeavour's launch is targeted for June 13. Photo credit: NASA/Kim Shiflett

CAPE CANAVERAL, Fla. – At the slidewire basket landing area near Launch Pad 39A at NASA's Kennedy Space Center in Florida, STS-127 crew members practice getting out of a basket. The baskets are used for emergency exits from the pad. Inside the basket are Mission Specialists Julie Payette and Tim Kopra. The crew is at Kennedy for a launch dress rehearsal called the terminal countdown demonstration test, or TCDT, which includes emergency exit training and equipment familiarization. Endeavour's STS-127 mission is the final of three flights dedicated to the assembly of the Japanese Kibo laboratory complex on the International Space Station. Endeavour's launch is targeted for June 13. Photo credit: NASA/Kim Shiflett

CAPE CANAVERAL, Fla. – At the slidewire basket landing area near Launch Pad 39A at NASA's Kennedy Space Center in Florida, STS-127 crew members learn about landing procedures during an emergency exit from the pad. From left are Mission Specialist Tom Marshburn, Commander Mark Polansky, and Mission Specialists Tim Kopra, Julie Payette, Christopher Cassidy, Dave Wolf and (far right) Pilot Doug Hurley. The crew is at Kennedy for a launch dress rehearsal called the terminal countdown demonstration test, or TCDT, which includes emergency exit training and equipment familiarization. Endeavour's STS-127 mission is the final of three flights dedicated to the assembly of the Japanese Kibo laboratory complex on the International Space Station. Endeavour's launch is targeted for June 13. Photo credit: NASA/Kim Shiflett

CAPE CANAVERAL, Fla. – On Launch Pad 39A at NASA's Kennedy Space Center in Florida, STS-127 crew members learn about emergency exit procedures from the launch pad. At left are Mission Specialists Christopher Cassidy and Julie Payette (behind him). At center are Commander Mark Polansky and Mission Specialist Dave Wolf. At right are Mission Specialists Tom Marshburn and Tim Kopra. The crew is at Kennedy for a launch dress rehearsal called the terminal countdown demonstration test, or TCDT, which includes emergency exit training and equipment familiarization. Endeavour's STS-127 mission is the final of three flights dedicated to the assembly of the Japanese Kibo laboratory complex on the International Space Station. Endeavour's launch is targeted for June 13. Photo credit: NASA/Kim Shiflett

CAPE CANAVERAL, Fla. – At the slidewire basket landing area near Launch Pad 39A at NASA's Kennedy Space Center in Florida, STS-127 Mission Specialist Julie Payette practices getting out of a basket, which are used for emergency exits from the pad. The crew is at Kennedy for a launch dress rehearsal called the terminal countdown demonstration test, or TCDT, which includes emergency exit training and equipment familiarization. Endeavour's STS-127 mission is the final of three flights dedicated to the assembly of the Japanese Kibo laboratory complex on the International Space Station. Endeavour's launch is targeted for June 13. Photo credit: NASA/Kim Shiflett

CAPE CANAVERAL, Fla. – On Launch Pad 39A at NASA's Kennedy Space Center in Florida, STS-127 crew members gather near space shuttle Endeavour's hatch to place the mission plaque before launch. Clockwise from left are Pilot Doug Hurley, Mission Specialists Julie Payette, Christopher Cassidy, Dave Wolf, Tom Marshburn and Tim Kopra and Commander Mark Polansky. Payette represents the Canadian Space Agency. The crew is at Kennedy for a launch dress rehearsal called the terminal countdown demonstration test, or TCDT, which includes emergency exit training and equipment familiarization. Endeavour's STS-127 mission is the final of three flights dedicated to the assembly of the Japanese Kibo laboratory complex on the International Space Station. Endeavour's launch is targeted for June 13. Photo credit: NASA/Kim Shiflett

KENNEDY SPACE CENTER, Fla. -- STS-89 Mission Specialist Salizhan Sharipov of the Russian Space Agency stands in a slidewire basket on the emergency egress system at KSC’s Launch Pad 39A, as Jim Bell, USA senior instructor for technical training, explains the egress system to him and to STS-89 Mission Specialist Andrew Thomas, Ph.D, at right. Dr. Thomas will transfer to the Russian Space Station Mir and succeed David Wolf, M.D., who will return to Earth aboard Endeavour. The seven astronauts assigned to the eighth Shuttle-Mir docking flight are completing Terminal Countdown Demonstration Test (TCDT) activities. A dress rehearsal for launch, the TCDT includes emergency egress training at the launch pad and culminates with a simulated countdown. The Space Shuttle Endeavour is undergoing preparations for liftoff, scheduled for Jan. 22. Dr. Thomas will live and work on Mir until June

CAPE CANAVERAL, Fla. – On Launch Pad 39A at NASA's Kennedy Space Center in Florida, STS-119 Mission Specialists Koichi Wakata and John Phillips complete emergency egress training from the pad. Practicing emergency egress is part of the prelaunch preparation known as Terminal Countdown Demonstration Test. The TCDT also includes equipment familiarization. Discovery is targeted to launch on the STS-119 mission Feb. 12. During the 14-day mission, the crew will install the S6 truss segment and solar arrays to the starboard side of the International Space Station, completing the station's truss, or backbone. Photo credit: NASA/Kim Shiflett

KENNEDY SPACE CENTER, FLA. -- From the 195-foot level of the fixed service structure on Launch Pad 39A, STS-117 Mission Specialists Patrick Forrester (front) and Steven Swanson sit in a slidewire basket, part of the emergency egress system. They and other crew members are practicing the emergency egress procedure to get off the pad, part of the prelaunch preparations known as terminal countdown demonstration test (TCDT). The TCDT also includes M-113 armored personnel carrier training and payload familiarization. The STS-117 mission is No. 21 to the International Space Station. Mission payloads aboard Atlantis include the S3/S4 integrated truss structure, a third set of solar arrays and batteries. The crew of six astronauts will install the truss to continue assembly of the station. Launch is scheduled for no earlier than March 15. Photo credit: NASA/Kim Shiflett.

KENNEDY SPACE CENTER, FLA. -- Mission STS-117 Commander Rick Sturckow (right) gives a thumbs up after he and Pilot Lee Archambault practice emergency egress procedures in a slidewire basket at the 195-foot level of the fixed service structure on Launch Pad 39A. They and other crew members are practicing the emergency egress procedure to get off the pad, part of the prelaunch preparations known as terminal countdown demonstration test (TCDT). The TCDT also includes M-113 armored personnel carrier training and payload familiarization. The STS-117 mission is No. 21 to the International Space Station. Mission payloads aboard Atlantis include the S3/S4 integrated truss structure, a third set of solar arrays and batteries. The crew of six astronauts will install the truss to continue assembly of the station. Launch is scheduled for no earlier than March 15. Photo credit: NASA/Kim Shiflett.

KENNEDY SPACE CENTER, FLA. -- Following the simulated launch countdown, STS-123 Mission Specialists Mike Foreman (left) and Robert L. Behnken settle in a slidewire basket on Launch Pad 39A at NASA's Kennedy Space Center. The crew is practicing emergency egress from the pad. The countdown was the culmination of the terminal countdown demonstration test, or TCDT. The TCDT provides astronauts and ground crews with an opportunity to participate in various countdown activities, including equipment familiarization and emergency egress training. Endeavour is targeted to launch at 2:28 a.m. EDT March 11 on the 16-day STS-123 mission to the International Space Station. Endeavour and its crew will deliver the first section of the Japan Aerospace Exploration Agency's Kibo laboratory and the Canadian Space Agency's two-armed robotic system, Dextre. Photo credit: NASA/Kim Shiflett

KENNEDY SPACE CENTER, Fla. -- Jim Bell, USA senior instructor for technical training, explains the emergency egress system at KSC’s Launch Pad 39A to, left to right, STS-89 Mission Specialists Andrew Thomas, Ph.D., who will transfer to the Russian Space Station Mir, and Bonnie Dunbar, Ph.D., as well as to Commander Terrence Wilcutt. Dr. Thomas will succeed David Wolf, M.D., who will return to Earth aboard Endeavour. The seven astronauts assigned to the eighth Shuttle-Mir docking flight are completing Terminal Countdown Demonstration Test (TCDT) activities at KSC. A dress rehearsal for launch, the TCDT includes emergency egress training at the launch pad and culminates with a simulated countdown. The Space Shuttle Endeavour is undergoing preparations for liftoff, scheduled for Jan. 22. Dr. Thomas will live and work on Mir until June

KENNEDY SPACE CENTER, FLA. -- From the 195-foot level of the fixed service structure on Launch Pad 39A, STS-117 Mission Specialists Danny Olivas (front) and James Reilly sit in a slidewire basket, part of the emergency egress system. They and other crew members are practicing the emergency egress procedure to get off the pad, part of the prelaunch preparations known as terminal countdown demonstration test (TCDT). The TCDT also includes M-113 armored personnel carrier training and payload familiarization. The STS-117 mission is No. 21 to the International Space Station. Mission payloads aboard Atlantis include the S3/S4 integrated truss structure, a third set of solar arrays and batteries. The crew of six astronauts will install the truss to continue assembly of the station. Launch is scheduled for no earlier than March 15. Photo credit: NASA/Kim Shiflett.

KENNEDY SPACE CENTER, Fla. -- On an upper level of the Pad 39A fixed service structure, the STS-118 crew get instructions from a trainer about using the emergency egress system. The crew members seen here are, from left, Commander Scott Kelly and Mission Specialists Barbara R. Morgan, Tracy Caldwell and Dave Williams. Morgan joined NASA's Teacher in Space program in 1985 and was selected as an astronaut in 1998. Williams represents the Canadian Space Agency. The crew is at Kennedy for training activities in the terminal countdown demonstration test, or TCDT. TCDT activities include M-113 training, payload familiarization, the emergency egress training at the pad and a simulated launch countdown. The mission is the 22nd flight to the International Space Station and Space Shuttle Endeavour will carry a payload including the S5 truss, a SPACEHAB module and external stowage platform 3. STS-118 is targeted for launch on Aug. 7. NASA/George Shelton

KENNEDY SPACE CENTER, Fla. -- On an upper level of the Pad 39A fixed service structure, the STS-118 crew members look at the slidewire basket that is part of the emergency egress system. On the left are Commander Scott Kelly and Mission Specialists Barbara R. Morgan, Tracy Caldwell, Dave Williams and Alvin Drew. On the right is Mission Specialist Rick Mastracchio. Morgan joined NASA's Teacher in Space program in 1985 and was selected as an astronaut in 1998. Williams represents the Canadian Space Agency. The crew is at Kennedy for training activities in the terminal countdown demonstration test, or TCDT. TCDT activities include M-113 training, payload familiarization, the emergency egress training at the pad and a simulated launch countdown. The mission is the 22nd flight to the International Space Station and Space Shuttle Endeavour will carry a payload including the S5 truss, a SPACEHAB module and external stowage platform 3. STS-118 is targeted for launch on Aug. 7. NASA/George Shelton

CAPE CANAVERAL, Fla. -- On Launch Pad 39A at NASA's Kennedy Space Center, STS-124 crew members climb into the slidewire baskets on the 195-foot level of the fixed service structure. The baskets are used for emergency egress, part of the launch dress rehearsal known as the terminal countdown demonstration test. TCDT provides astronauts and ground crews with an opportunity to participate in various simulated countdown activities, including a simulated launch countdown, equipment familiarization and emergency egress training. On the STS-124 mission, the crew will deliver and install the Japanese Experiment Module – Pressurized Module and Japanese Remote Manipulator System. Discovery's launch is targeted for May 31. Photo credit: NASA/Kim Shiflett

KENNEDY SPACE CENTER, FLA. -- Mission STS-117 Commander Rick Sturckow speaks to the media during a question-and-answer session at Launch Pad 39A during Terminal Countdown Demonstration Test (TCDT) activities. The TCDT also includes M-113 armored personnel carrier training, pad emergency egress training and a simulated launch countdown. The mission payload aboard Space Shuttle Atlantis is the S3/S4 integrated truss structure, along with a third set of solar arrays and batteries. The crew of six astronauts will install the truss to continue assembly of the International Space Station. Photo credit: NASA/Kim Shiflett

KENNEDY SPACE CENTER, Fla. -- STS-89 Mission Specialists Bonnie Dunbar, Ph.D., and Andrew Thomas, Ph.D., check out oxygen masks in the bunker at KSC’s Launch Pad 39A. The seven astronauts assigned to the eighth Shuttle-Mir docking flight are completing Terminal Countdown Demonstration Test (TCDT) activities. A dress rehearsal for launch, the TCDT includes emergency egress training at the launch pad and culminates with a simulated countdown. Dr. Thomas will transfer to the Russian Space Station Mir and succeed David Wolf, M.D., who will return to Earth aboard Endeavour. The Space Shuttle Endeavour is undergoing preparations for liftoff, scheduled for Jan. 22. Dr. Thomas will live and work on Mir until June

KENNEDY SPACE CENTER, Fla. -- In the slidewire basket bunker area of Launch Pad 39A, STS-118 Mission Specialist Dave Williams is introduced to the press during a media interview before the crew's morning training activities in the terminal countdown demonstration test, or TCDT. Williams represents the Canadian Space Agency. TCDT activities include M-113 training, payload familiarization, the emergency egress training at the pad and a simulated launch countdown. The mission is the 22nd flight to the International Space Station and Space Shuttle Endeavour will carry a payload including the S5 truss, a SPACEHAB module and external stowage platform 3. STS-118 is targeted for launch on Aug. 7. Photo credit: NASA/Ken Thornsley

KENNEDY SPACE CENTER, Fla. -- On the slidewire basket bunker area of Launch Pad 39A, STS-118 Commander Scott Kelly talks to the media before the crew's morning training activities in the terminal countdown demonstration test, or TCDT. TCDT activities include M-113 training, payload familiarization, the emergency egress training at the pad and a simulated launch countdown. The mission is the 22nd flight to the International Space Station and Space Shuttle Endeavour will carry a payload including the S5 truss, a SPACEHAB module and external stowage platform 3. STS-118 is targeted for launch on Aug. 7. NASA/George Shelton

CAPE CANAVERAL, Fla. – Following the simulated launch countdown on Launch Pad 39A at NASA's Kennedy Space Center in Florida, STS-119 Commander Lee Archambault and Pilot Tony Antonelli take seats in the slidewire basket used for emergency egress from the pad. The practice egress is part of the prelaunch preparation known as Terminal Countdown Demonstration Test. The TCDT also includes equipment familiarization. Discovery is targeted to launch on the STS-119 mission Feb. 12. During the 14-day mission, the crew will install the S6 truss segment and solar arrays to the starboard side of the International Space Station, completing the station's truss, or backbone. Photo credit: NASA/Kim Shiflett

KENNEDY SPACE CENTER, FLA. -- Following the simulated launch countdown, STS-123 Mission Specialists Mike Foreman (left) and Robert L. Behnken complete their emergency egress practice on Launch Pad 39A at NASA's Kennedy Space Center. The countdown was the culmination of the terminal countdown demonstration test, or TCDT. The TCDT provides astronauts and ground crews with an opportunity to participate in various countdown activities, including equipment familiarization and emergency egress training. Endeavour is targeted to launch at 2:28 a.m. EDT March 11 on the 16-day STS-123 mission to the International Space Station. Endeavour and its crew will deliver the first section of the Japan Aerospace Exploration Agency's Kibo laboratory and the Canadian Space Agency's two-armed robotic system, Dextre. Photo credit: NASA/Kim Shiflett

KENNEDY SPACE CENTER, Fla. --STS-82 Mission Commander Kenneth D. Bowersox, at right, and Pilot Scott J. "Doc" Horowitz practice emergency egress procedures in a slidewire basket at Launch Pad 39A as part of Terminal Countdown Demonstration Test (TCDT) activities. STS-82 will be the second Hubble Space Telescope servicing mission. Liftoff is targeted for Feb. 11

KENNEDY SPACE CENTER, Fla. -- STS-88 Mission Specialists Sergei Krikalev and James H. Newman practice emergency egress procedures in a slidewire basket at Launch Pad 39A as part of Terminal Countdown Demonstration Test (TCDT) activities, a dress rehearsal for launch. Mission STS-88 is targeted for launch on Dec. 3, 1998. It is the first U.S. flight for the assembly of the International Space Station and will carry the Unity connecting module

KENNEDY SPACE CENTER, Fla. -- STS-86 Mission Specialists Vladimir Georgievich Titov of the Russian Space Agency, at left, and Scott E. Parazynski practice emergency egress procedures in a slidewire basket as part of Terminal Countdown Demonstration Test (TCDT) activities at Launch Pad 39A. Titov and Parazynski are scheduled to perform a spacewalk during the STS-86 mission, which will be the seventh docking of the Space Shuttle with the Russian Space Station Mir. Liftoff of the Space Shuttle Atlantis on Mission STS-86 is targeted for Sept. 25

KENNEDY SPACE CENTER, Fla. -- STS-82 crew members practice emergency egress procedures in a slidewire basket at Launch Pad 39A as part of Terminal Countdown Demonstration Test (TCDT) activities. From left, are Mission Specialists Gregory J. Harbaugh and Steven L. Smith and Payload Commander Mark C. Lee. STS-82 will be the second Hubble Space Telescope servicing mission. Liftoff is targeted for Feb. 11

KENNEDY SPACE CENTER, Fla. -- STS-86 Commander James D. Wetherbee, at right, and Pilot Michael J. Bloomfield practice emergency egress procedures in a slidewire basket as part of Terminal Countdown Demonstration Test (TCDT) activities at Launch Pad 39A. STS-86 will be the seventh docking of the Space Shuttle with the Russian Space Station Mir. Liftoff of the Space Shuttle Atlantis on Mission STS-86 is targeted for Sept. 25

STS-83 Payload Specialist Gregory T. Linteris, Mission Specialist Janice E. Voss, and Payload Specialist Roger K. Crouch participate in emergency egress training at Launch Complex 39A during the crew's <a href="http://www-pao.ksc.nasa.gov/kscpao/release/1997/40-97.htm">Terminal Countdown Demonstration Test (TCDT).</a> They are seen here in one of the pads' seven <a href="http://www-pao.ksc.nasa.gov/kscpao/nasafact/pads.htm#emergenc">slidewire baskets.</a

CAPE CANAVERAL, Fla. – Following the simulated launch countdown on Launch Pad 39A at NASA's Kennedy Space Center in Florida, STS-119 crew members are in the slidewire basket they would use during an emergency egress. The slidewire basket could propel them to a landing area below, if needed. The practice egress is part of the prelaunch preparation known as Terminal Countdown Demonstration Test. The TCDT also includes equipment familiarization. Discovery is targeted to launch on the STS-119 mission Feb. 12. During the 14-day mission, the crew will install the S6 truss segment and solar arrays to the starboard side of the International Space Station, completing the station's truss, or backbone. Photo credit: NASA/Kim Shiflett

CAPE CANAVERAL, Fla. – Following the simulated launch countdown on Launch Pad 39A at NASA's Kennedy Space Center in Florida, STS-119 crew members are in the slidewire basket they would use during an emergency egress. The slidewire basket could propel them to a landing area below, if needed. The practice egress is part of the prelaunch preparation known as Terminal Countdown Demonstration Test. The TCDT also includes equipment familiarization. Discovery is targeted to launch on the STS-119 mission Feb. 12. During the 14-day mission, the crew will install the S6 truss segment and solar arrays to the starboard side of the International Space Station, completing the station's truss, or backbone. Photo credit: NASA/Kim Shiflett

KENNEDY SPACE CENTER, FLA. -- In the white room on Launch Pad 39A, an STS-120 crew member crawls through the hatch after the simulated launch countdown, culmination of the prelaunch terminal countdown demonstration test, or TCDT. The crew will also practice emergency egress from the pad. The TCDT at NASA's Kennedy Space Center provides astronauts and ground crews an opportunity to participate in various launch preparation activities, including equipment familiarization and emergency training. The STS-120 mission will deliver the U.S. Node 2 module, named Harmony, aboard space shuttle Discovery to the International Space Station. Discovery is targeted to launch on its 14-day mission at 11:38 a.m. EDT on Oct. 23. Photo credit: NASA/Kim Shiflett

KENNEDY SPACE CENTER, Fla. -- On an upper level of the Pad 39A fixed service structure, the STS-118 crew members get directions about using the slidewire basket that is part of the emergency egress system. At right, Mission Specialist Tracy Caldwell identifies the pull lever to release the basket. At far left is Mission Specialist Dave Williams, who represents the Canadian Space Agency. At center is Mission Specialist Alvin Drew. The crew is at Kennedy for terminal countdown demonstration test, or TCDT, training activities. Those activities include M-113 training, payload familiarization, the emergency egress training at the pad and a simulated launch countdown. The mission is the 22nd flight to the International Space Station and Space Shuttle Endeavour will carry a payload including the S5 truss, a SPACEHAB module and external stowage platform 3. STS-118 is targeted for launch on Aug. 7. NASA/George Shelton

KENNEDY SPACE CENTER, FLA. -- At the 195-foot level of the fixed service structure on Launch Pad 39A, STS-117 crew members receive instruction on emergency egress during Terminal Countdown Demonstration Test activities. From left are Commander Rick Sturckow, Mission Specialist Danny Olivas and Pilot Lee Archambault. They and other crew members are practicing the emergency egress procedure using the slidewire basket system to get off the pad. The TCDT also includes M-113 armored personnel carrier training, and a simulated launch countdown. The mission payload aboard Space Shuttle Atlantis is the S3/S4 integrated truss structure, along with a third set of solar arrays and batteries. The crew of six astronauts will install the truss to continue assembly of the International Space Station. Photo credit: NASA/Kim Shiflett

KENNEDY SPACE CENTER, FLA. -- From the 195-foot level of the fixed service structure on Launch Pad 39A, STS-117 Pilot Lee Archambault (front) and Commander Rick Sturckow sit in a slidewire basket, part of the emergency egress system. They and other crew members are practicing the emergency egress procedure to get off the pad, part of the prelaunch preparations known as terminal countdown demonstration test. The TCDT also includes M-113 armored personnel carrier training and payload familiarization. The STS-117 mission is No. 21 to the International Space Station. Mission payloads aboard Atlantis include the S3/S4 integrated truss structure, a third set of solar arrays and batteries. The crew of six astronauts will install the truss to continue assembly of the station. Launch is scheduled for no earlier than March 15. Photo credit: NASA/Kim Shiflett.

CAPE CANAVERAL, Fla. – On Launch Pad 39A at NASA's Kennedy Space Center in Florida, STS-119 crew members gather around the slidewire baskets used for emergency egress from the pad. From left are Mission Specialist Steve Swanson, Pilot Tony Antonelli, Mission Specialist Koichi Wakata, Commander Lee Archambault and Mission Specialist John Phillips. Practicing emergency egress is part of the prelaunch preparation known as Terminal Countdown Demonstration Test. The TCDT also includes equipment familiarization. Discovery is targeted to launch on the STS-119 mission Feb. 12. During the 14-day mission, the crew will install the S6 truss segment and solar arrays to the starboard side of the International Space Station, completing the station's truss, or backbone. Photo credit: NASA/Kim Shiflett

CAPE CANAVERAL, Fla. – Following the simulated launch countdown on Launch Pad 39A at NASA's Kennedy Space Center in Florida, STS-119 Mission Specialists Joseph Acaba (left) and Richard Arnold are seated in a slidewire basket that could propel them to a landing area below. The slidewire basket is used for emergency egress from the pad. In the background at left are Mission Specialists Richard Arnold and Koichi Wakata. The countdown and emergency egress are part of the prelaunch preparation known as Terminal Countdown Demonstration Test. The TCDT also includes equipment familiarization. Discovery is targeted to launch on the STS-119 mission Feb. 12. During the 14-day mission, the crew will install the S6 truss segment and solar arrays to the starboard side of the International Space Station, completing the station's truss, or backbone. Photo credit: NASA/Kim Shiflett

CAPE CANAVERAL, Fla. – Following the simulated launch countdown on Launch Pad 39A at NASA's Kennedy Space Center in Florida, STS-119 Mission Specialists Joseph Acaba (left) and Richard Arnold practice emergency egress from the pad. They are seated in a slidewire basket that could propel them to a landing area below. The countdown and emergency egress are part of the prelaunch preparation known as Terminal Countdown Demonstration Test. The TCDT also includes equipment familiarization. Discovery is targeted to launch on the STS-119 mission Feb. 12. During the 14-day mission, the crew will install the S6 truss segment and solar arrays to the starboard side of the International Space Station, completing the station's truss, or backbone. Photo credit: NASA/Kim Shiflett

KENNEDY SPACE CENTER, FLA. -- At the 195-foot level of the fixed service structure on Launch Pad 39A, STS-117 crew members receive instruction on emergency egress during Terminal Countdown Demonstration Test activities. From left are Mission Specialist Danny Olivas, Commander Rick Sturckow, Pilot Lee Archambault, and Mission Specialists James Reilly, Steven Swanson and Patrick Forrester. They are practicing the emergency egress procedure using the slidewire basket system to get off the pad. The TCDT also includes M-113 armored personnel carrier training, and a simulated launch countdown. The mission payload aboard Space Shuttle Atlantis is the S3/S4 integrated truss structure, along with a third set of solar arrays and batteries. The crew of six astronauts will install the truss to continue assembly of the International Space Station. Photo credit: NASA/Kim Shiflett

KENNEDY SPACE CENTER, Fla. -- During a break in their Terminal Countdown Demonstration Test (TCDT), the STS-101 crew poses in front of Space Shuttle Atlantis at Launch Pad 39A. Standing, left to right, are Mission Specialists Susan J. Helms and Yury Usachev of Russia; Pilot Scott J. "Doc" Horowitz; Commander James D. Halsell Jr.; and Mission Specialists Mary Ellen Weber, James Voss and Jeffrey N. Williams. The TCDT includes emergency egress training and a simulated launch countdown. During their mission to the International Space Station, the STS-101 crew will be delivering logistics and supplies, plus preparing the Station for the arrival of the Zvezda Service Module, expected to be launched by Russia in July 2000. Also, the crew will conduct one space walk to perform maintenance on the Space Station. This will be the third assembly flight for the Space Station. STS-101 is scheduled to launch April 24 at 4:15 p.m. from Launch Pad 39A

KENNEDY SPACE CENTER, Fla. -- After Terminal Countdown Demonstration Test (TCDT) activities at Launch Pad 39A, the STS-101 crew talk to the media. At the microphone is Commander James D. Halsell Jr. Next to him, standing left to right, are Pilot Scott J. "Doc" Horowitz and Mission Specialists Mary Ellen Weber, Jeffrey N. Williams, James Voss, Susan J. Helms and Yury Usachev of Russia. The TCDT includes emergency egress training and a simulated launch countdown. During their mission to the International Space Station, the STS-101 crew will be delivering logistics and supplies, plus preparing the Station for the arrival of the Zvezda Service Module, expected to be launched by Russia in July 2000. Also, the crew will conduct one space walk to perform maintenance on the Space Station. This will be the third assembly flight for the Space Station. STS-101 is scheduled to launch April 24 at 4:15 p.m. from Launch Pad 39A

KENNEDY SPACE CENTER, Fla. -- After Terminal Countdown Demonstration Test (TCDT) activities at Launch Pad 39A, the STS-101 crew talk to the media. At the microphone is Commander James D. Halsell Jr. Next to him, standing left to right, are Pilot Scott J. "Doc" Horowitz and Mission Specialists Mary Ellen Weber, Jeffrey N. Williams, James Voss, Susan J. Helms and Yury Usachev of Russia. The TCDT includes emergency egress training and a simulated launch countdown. During their mission to the International Space Station, the STS-101 crew will be delivering logistics and supplies, plus preparing the Station for the arrival of the Zvezda Service Module, expected to be launched by Russia in July 2000. Also, the crew will conduct one space walk to perform maintenance on the Space Station. This will be the third assembly flight for the Space Station. STS-101 is scheduled to launch April 24 at 4:15 p.m. from Launch Pad 39A

Inside the White Room at Launch Pad 39A, the STS-101 crew take part in training during a Terminal Countdown Demonstration Test (TCDT). Activities during TCDT include emergency egress from the orbiter and a dress rehearsal for launch. Standing left to right are Pilot Scott Horowitz, Mission Specialists Mary Ellen Weber, Yury Usachev and Jeffrey Williams, Commander James Halsell, and Mission Specialists James Voss and Susan Helms. During their mission to the International Space Station, the STS-101 crew will be delivering logistics and supplies, plus preparing the Station for the arrival of the Zvezda Service Module, expected to be launched by Russia in July 2000. Also, the crew will conduct one space walk to perform maintenance on the Space Station. This will be the third assembly flight for the Space Station. STS-101 is scheduled to launch April 24 at 4:15 p.m. from Launch Pad 39A

KENNEDY SPACE CENTER, Fla. -- During a break in their Terminal Countdown Demonstration Test (TCDT), the STS-101 crew poses in front of Space Shuttle Atlantis at Launch Pad 39A. Standing, left to right, are Mission Specialists Susan J. Helms and Yury Usachev of Russia; Pilot Scott J. "Doc" Horowitz; Commander James D. Halsell Jr.; and Mission Specialists Mary Ellen Weber, James Voss and Jeffrey N. Williams. The TCDT includes emergency egress training and a simulated launch countdown. During their mission to the International Space Station, the STS-101 crew will be delivering logistics and supplies, plus preparing the Station for the arrival of the Zvezda Service Module, expected to be launched by Russia in July 2000. Also, the crew will conduct one space walk to perform maintenance on the Space Station. This will be the third assembly flight for the Space Station. STS-101 is scheduled to launch April 24 at 4:15 p.m. from Launch Pad 39A

KENNEDY SPACE CENTER, Fla. --In the White Room on Launch Pad 39A, STS-118 Mission Specialist Rick Mastracchio is eager to enter Space Shuttle Endeavour for a simulated launch countdown, the culmination of terminal countdown demonstration test activities. The White Room is situated at the end of the orbiter access arm and provides entry into the orbiter. TCDT activities also include M-113 training, payload familiarization and emergency egress training at the pad. The mission is the 22nd flight to the International Space Station and Space Shuttle Endeavour will carry a payload including the S5 truss, a SPACEHAB module and external stowage platform 3. STS-118 is targeted for launch on Aug. 7. Photo credit: NASA/Amanda Diller

KENNEDY SPACE CENTER, Fla. -- In the slidewire basket bunker area of Launch Pad 39A, STS-118 Mission Specialist Tracy Caldwell reacts to the waiting press during a media interview before the crew's morning training activities in the terminal countdown demonstration test, or TCDT. Those activities include M-113 training, payload familiarization, the emergency egress training at the pad and a simulated launch countdown. The mission is the 22nd flight to the International Space Station and Space Shuttle Endeavour will carry a payload including the S5 truss, a SPACEHAB module and external stowage platform 3. STS-118 is targeted for launch on Aug. 7. Photo credit: NASA/Ken Thornsley

KENNEDY SPACE CENTER, Fla. -- In the slidewire basket bunker area of Launch Pad 39A, STS-118 Pilot Charlie Hobaugh waits to begin a media interview before the crew's morning training activities in the terminal countdown demonstration test, or TCDT. Those activities include M-113 training, payload familiarization, the emergency egress training at the pad and a simulated launch countdown. The mission is the 22nd flight to the International Space Station and Space Shuttle Endeavour will carry a payload including the S5 truss, a SPACEHAB module and external stowage platform 3. STS-118 is targeted for launch on Aug. 7. Photo credit: NASA/Ken Thornsley

KENNEDY SPACE CENTER, Fla. -- In the slidewire basket bunker area of Launch Pad 39A, STS-118 Mission Specialist Rick Mastracchio waits to begin a media interview before the crew's morning training activities in the terminal countdown demonstration test, or TCDT. Those activities include M-113 training, payload familiarization, the emergency egress training at the pad and a simulated launch countdown. The mission is the 22nd flight to the International Space Station and Space Shuttle Endeavour will carry a payload including the S5 truss, a SPACEHAB module and external stowage platform 3. STS-118 is targeted for launch on Aug. 7. Photo credit: NASA/Ken Thornsley

KENNEDY SPACE CENTER, Fla. -- In the slidewire basket bunker area of Launch Pad 39A, STS-118 Mission Specialist Alvin Drew waits to begin a media interview before the crew's morning training activities in the terminal countdown demonstration test, or TCDT. Those activities include M-113 training, payload familiarization, the emergency egress training at the pad and a simulated launch countdown. The mission is the 22nd flight to the International Space Station and Space Shuttle Endeavour will carry a payload including the S5 truss, a SPACEHAB module and external stowage platform 3. STS-118 is targeted for launch on Aug. 7. Photo credit: NASA/Ken Thornsley

KENNEDY SPACE CENTER, Fla. -- In the slidewire basket bunker area of Launch Pad 39A, STS-118 Mission Specialist Tracy Caldwell reacts to the waiting press during a media interview before the crew's morning training activities in the terminal countdown demonstration test, or TCDT. Those activities include M-113 training, payload familiarization, the emergency egress training at the pad and a simulated launch countdown. The mission is the 22nd flight to the International Space Station and Space Shuttle Endeavour will carry a payload including the S5 truss, a SPACEHAB module and external stowage platform 3. STS-118 is targeted for launch on Aug. 7. Photo credit: NASA/Ken Thornsley

KENNEDY SPACE CENTER, Fla. -- In the slidewire basket bunker area of Launch Pad 39A, STS-118 Commander Scott Kelly talks to the media at a press conference before the crew's morning training activities in the terminal countdown demonstration test, or TCDT. Those activities include M-113 training, payload familiarization, the emergency egress training at the pad and a simulated launch countdown. The mission is the 22nd flight to the International Space Station and Space Shuttle Endeavour will carry a payload including the S5 truss, a SPACEHAB module and external stowage platform 3. STS-118 is targeted for launch on Aug. 7. Photo credit: NASA/Ken Thornsley

KENNEDY SPACE CENTER, Fla. -- In the slidewire basket bunker area of Launch Pad 39A, STS-118 Commander Scott Kelly waits to begin a media interview before the crew's morning training activities in the terminal countdown demonstration test, or TCDT. Those activities include M-113 training, payload familiarization, the emergency egress training at the pad and a simulated launch countdown. The mission is the 22nd flight to the International Space Station and Space Shuttle Endeavour will carry a payload including the S5 truss, a SPACEHAB module and external stowage platform 3. STS-118 is targeted for launch on Aug. 7. Photo credit: NASA/Ken Thornsley

KENNEDY SPACE CENTER, FLA. -- During emergency egress from Launch Pad 39A, STS-120 Mission Specialists Stephanie Wilson (left) and Doug Wheelock settle in the slidewire basket. The basket can carry them to a safe landing site below, if needed. The activity is part of the prelaunch terminal countdown demonstration test, or TCDT. The TCDT at NASA's Kennedy Space Center provides astronauts and ground crews an opportunity to participate in various launch preparation activities, including equipment familiarization and emergency training. The STS-120 mission will deliver the U.S. Node 2 module, named Harmony, aboard space shuttle Discovery to the International Space Station. Discovery is targeted to launch on its 14-day mission at 11:38 a.m. EDT on Oct. 23. Photo credit: NASA/Kim Shiflett

KENNEDY SPACE CENTER, FLA. -- During emergency egress from Launch Pad 39A, STS-120 crew members are in the slidewire basket. In front, Mission Specialist Paolo Nespoli holds the release lever. Behind him are Mission Specialists Daniel Tani and Scott Parazynski. The basket can carry them to a safe landing site below, if needed. Nespoli represents the European Space Agency. The activity is part of the prelaunch terminal countdown demonstration test, or TCDT. The TCDT at NASA's Kennedy Space Center provides astronauts and ground crews an opportunity to participate in various launch preparation activities, including equipment familiarization and emergency training. The STS-120 mission will deliver the U.S. Node 2 module, named Harmony, aboard space shuttle Discovery to the International Space Station. Discovery is targeted to launch on its 14-day mission at 11:38 a.m. EDT on Oct. 23. Photo credit: NASA/Kim Shiflett

KENNEDY SPACE CENTER, FLA. -- The STS-120 crew gathers at the slidewire basket area on Launch Pad 39A after practicing emergency egress, part of the prelaunch terminal countdown demonstration test, or TCDT. Seen here in their launch and entry suits are (from left) Pilot George Zamka, Commander Pamela Melroy and Mission Specialist Scott Parazynski. Their name patches reflect the nicknames the crew gave each other for the event. The TCDT at NASA's Kennedy Space Center provides astronauts and ground crews an opportunity to participate in various launch preparation activities, including equipment familiarization and emergency training. The STS-120 mission will deliver the U.S. Node 2 module, named Harmony, aboard space shuttle Discovery to the International Space Station. Discovery is targeted to launch on its 14-day mission at 11:38 a.m. EDT on Oct. 23. Photo credit: NASA/Kim Shiflett

KENNEDY SPACE CENTER, FLA. -- Members of space shuttle Atlantis' STS-122 crew practice emergency exit procedures in a slidewire basket at Launch Pad 39A following a simulated launch countdown. The exercise is part of terminal countdown demonstration test, or TCDT, activities at NASA's Kennedy Space Center. The TCDT is a dress rehearsal for launch and also provides astronauts and ground crews with equipment familiarization and emergency egress training. On mission STS-122, Atlantis will deliver the Columbus module to the International Space Station. The European Space Agency's largest single contribution to the station, Columbus is a multifunctional, pressurized laboratory that will be permanently attached to U.S. Node 2, called Harmony. The laboratory will expand the research facilities aboard the station, providing crew members and scientists from around the world the ability to conduct a variety of experiments in the physical, materials and life sciences. Atlantis' launch is targeted for Dec. 6. Photo credit: NASA/Kim Shiflett

KENNEDY SPACE CENTER, FLA. -- During emergency egress from Launch Pad 39A, STS-120 Pilot George Zamka and Commander Pamela Melroy are in one of the slidewire baskets. Zamka, at left, reaches for the release lever. The basket can carry them to a safe landing site below, if needed. The activity is part of the prelaunch terminal countdown demonstration test, or TCDT. The TCDT at NASA's Kennedy Space Center provides astronauts and ground crews an opportunity to participate in various launch preparation activities, including equipment familiarization and emergency training. The STS-120 mission will deliver the U.S. Node 2 module, named Harmony, aboard space shuttle Discovery to the International Space Station. Discovery is targeted to launch on its 14-day mission at 11:38 a.m. EDT on Oct. 23. Photo credit: NASA/Kim Shiflett

KENNEDY SPACE CENTER, FLA. -- During emergency egress from Launch Pad 39A, STS-120 Mission Specialists Stephanie Wilson (foreground) and Doug Wheelock settle in the slidewire basket. Wilson reaches for the release lever. The basket can carry them to a safe landing site below, if needed. The activity is part of the prelaunch terminal countdown demonstration test, or TCDT. The TCDT at NASA's Kennedy Space Center provides astronauts and ground crews an opportunity to participate in various launch preparation activities, including equipment familiarization and emergency training. The STS-120 mission will deliver the U.S. Node 2 module, named Harmony, aboard space shuttle Discovery to the International Space Station. Discovery is targeted to launch on its 14-day mission at 11:38 a.m. EDT on Oct. 23. Photo credit: NASA/Kim Shiflett

KENNEDY SPACE CENTER, FLA. -- During emergency egress from Launch Pad 39A, STS-120 Mission Specialists relax inside the slidewire basket. From left are Mission Specialists Paolo Nespoli, Daniel Tani and Scott Parazynski. The basket can carry them to a safe landing site below, if needed. The activity is part of the prelaunch terminal countdown demonstration test, or TCDT. The TCDT at NASA's Kennedy Space Center provides astronauts and ground crews an opportunity to participate in various launch preparation activities, including equipment familiarization and emergency training. The STS-120 mission will deliver the U.S. Node 2 module, named Harmony, aboard space shuttle Discovery to the International Space Station. Discovery is targeted to launch on its 14-day mission at 11:38 a.m. EDT on Oct. 23. Photo credit: NASA/Kim Shiflett

KENNEDY SPACE CENTER, FLA. -- During emergency egress from Launch Pad 39A, STS-120 Pilot George Zamka and Commander Pamela Melroy head for the slidewire baskets. The basket can carry them to a safe landing site below, if needed. The activity is part of the prelaunch terminal countdown demonstration test, or TCDT. The TCDT at NASA's Kennedy Space Center provides astronauts and ground crews an opportunity to participate in various launch preparation activities, including equipment familiarization and emergency training. The STS-120 mission will deliver the U.S. Node 2 module, named Harmony, aboard space shuttle Discovery to the International Space Station. Discovery is targeted to launch on its 14-day mission at 11:38 a.m. EDT on Oct. 23. Photo credit: NASA/Kim Shiflett

KENNEDY SPACE CENTER, FLA. -- STS-120 crew members practice emergency egress from Launch Pad 39A after completing a simulated launch countdown, culmination of the prelaunch terminal countdown demonstration test, or TCDT. Leading the way to the slidewire baskets is Mission Specialist Scott Parazynski, with Mission Specialist Daniel Tani and others behind him. The TCDT at NASA's Kennedy Space Center provides astronauts and ground crews an opportunity to participate in various launch preparation activities, including equipment familiarization and emergency training. The STS-120 mission will deliver the U.S. Node 2 module, named Harmony, aboard space shuttle Discovery to the International Space Station. Discovery is targeted to launch on its 14-day mission at 11:38 a.m. EDT on Oct. 23. Photo credit: NASA/Kim Shiflett

KENNEDY SPACE CENTER, FLA. -- During emergency egress from Launch Pad 39A, STS-120 Mission Specialists Stephanie Wilson (left) and Doug Wheelock head for the slidewire baskets. The basket can carry them to a safe landing site below, if needed. The activity is part of the prelaunch terminal countdown demonstration test, or TCDT. The TCDT at NASA's Kennedy Space Center provides astronauts and ground crews an opportunity to participate in various launch preparation activities, including equipment familiarization and emergency training. The STS-120 mission will deliver the U.S. Node 2 module, named Harmony, aboard space shuttle Discovery to the International Space Station. Discovery is targeted to launch on its 14-day mission at 11:38 a.m. EDT on Oct. 23. Photo credit: NASA/Kim Shiflett

KENNEDY SPACE CENTER, FLA. -- Members of space shuttle Atlantis' STS-122 crew practice emergency exit procedures in a slidewire basket at Launch Pad 39A following a simulated launch countdown. The exercise is part of terminal countdown demonstration test, or TCDT, activities at NASA's Kennedy Space Center. The TCDT is a dress rehearsal for launch and also provides astronauts and ground crews with equipment familiarization and emergency egress training. On mission STS-122, Atlantis will deliver the Columbus module to the International Space Station. The European Space Agency's largest single contribution to the station, Columbus is a multifunctional, pressurized laboratory that will be permanently attached to U.S. Node 2, called Harmony. The laboratory will expand the research facilities aboard the station, providing crew members and scientists from around the world the ability to conduct a variety of experiments in the physical, materials and life sciences. Atlantis' launch is targeted for Dec. 6. Photo credit: NASA/Kim Shiflett

KENNEDY SPACE CENTER, FLA. -- The STS-120 crew gathers at the slidewire basket area on Launch Pad 39A after practicing emergency egress, part of the prelaunch terminal countdown demonstration test, or TCDT. Seen here in their launch and entry suits are (from left) Pilot George Zamka, Commander Pamela Melroy and (far right) Mission Specialist Daniel Tani. Their name patches reflect the nicknames the crew gave each other for the event. The TCDT at NASA's Kennedy Space Center provides astronauts and ground crews an opportunity to participate in various launch preparation activities, including equipment familiarization and emergency training. The STS-120 mission will deliver the U.S. Node 2 module, named Harmony, aboard space shuttle Discovery to the International Space Station. Discovery is targeted to launch on its 14-day mission at 11:38 a.m. EDT on Oct. 23. Photo credit: NASA/Kim Shiflett

KENNEDY SPACE CENTER, Fla. -- STS-88 Mission Specialists Sergei Konstantinovich Krikalev (left) and James H. Newman (right) are ready to leave Launch Pad 39A in the slidewire basket during an emergency egress exercise. The crew are at KSC to participate in the Terminal Countdown Demonstration Test (TCDT) which includes mission familiarization activities, emergency egress training, and the simulated main engine cut-off exercise. Mission STS-88 is targeted for launch on Dec. 3, 1998. It is the first U.S. flight for the assembly of the International Space Station and will carry the Unity connecting module. Unity will be mated with the already orbiting Russian-built Zarya control module. The 12-day mission includes three planned spacewalks to connect power, data and utility lines and install exterior equipment

CAPE CANAVERAL, Fla. -- On Launch Pad 39A at NASA's Kennedy Space Center, STS-124 Pilot Ken Ham (left) and Commander Mark Kelly get seated in the slidewire basket on the 195-foot level of the fixed service structure. The baskets are used for emergency egress, part of the launch dress rehearsal known as the terminal countdown demonstration test. TCDT provides astronauts and ground crews with an opportunity to participate in various simulated countdown activities, including a simulated launch countdown, equipment familiarization and emergency egress training. On the STS-124 mission, the crew will deliver and install the Japanese Experiment Module – Pressurized Module and Japanese Remote Manipulator System. Discovery's launch is targeted for May 31. Photo credit: NASA/Kim Shiflett

KENNEDY SPACE CENTER, Fla. -- STS-88 Mission Specialist Jerry L. Ross (left) climbs into slideware basket behind Mission Specialist Nancy Jane Currie, Ph.D., (right) at Launch Pad 39A as part of an emergency egress exercise. The crew are at KSC to participate in the Terminal Countdown Demonstration Test (TCDT) which includes mission familiarization activities, emergency egress training, and the simulated main engine cut-off exercise. Mission STS-88 is targeted for launch on Dec. 3, 1998. It is the first U.S. flight for the assembly of the International Space Station and will carry the Unity connecting module. Unity will be mated with the already orbiting Russian-built Zarya control module. The 12-day mission includes three planned spacewalks to connect power, data and utility lines and install exterior equipment

KENNEDY SPACE CENTER, Fla. -- STS-88 Mission Specialists Sergei Konstantinovich Krikalev (left) and James H. Newman (right) are ready to leave Launch Pad 39A in the slidewire basket during an emergency egress exercise. The crew are at KSC to participate in the Terminal Countdown Demonstration Test (TCDT) which includes mission familiarization activities, emergency egress training, and the simulated main engine cut-off exercise. Mission STS-88 is targeted for launch on Dec. 3, 1998. It is the first U.S. flight for the assembly of the International Space Station and will carry the Unity connecting module. Unity will be mated with the already orbiting Russian-built Zarya control module. The 12-day mission includes three planned spacewalks to connect power, data and utility lines and install exterior equipment

KENNEDY SPACE CENTER, Fla. -- STS-88 Mission Specialists James H. Newman (left) and Sergei Konstantinovich Krikalev (right) hurry toward the slidewire basket at the 195-foot level of Launch Pad 39A during an emergency egress exercise. The crew are at KSC to participate in the Terminal Countdown Demonstration Test (TCDT) which includes mission familiarization activities, emergency egress training, and the simulated main engine cut-off exercise. Mission STS-88 is targeted for launch on Dec. 3, 1998. It is the first U.S. flight for the assembly of the International Space Station and will carry the Unity connecting module. Unity will be mated with the already orbiting Russian-built Zarya control module. The 12-day mission includes three planned spacewalks to connect power, data and utility lines and install exterior equipment

CAPE CANAVERAL, Fla. -- On Launch Pad 39A at NASA's Kennedy Space Center, STS-124 Mission Specialists Greg Chamitoff, Akihiko Hoshide and Mike Fossum have reached the slidewire baskets on the 195-foot level of the fixed service structure. The baskets are used for emergency egress, part of the launch dress rehearsal known as the terminal countdown demonstration test. TCDT provides astronauts and ground crews with an opportunity to participate in various simulated countdown activities, including a simulated launch countdown, equipment familiarization and emergency egress training. On the STS-124 mission, the crew will deliver and install the Japanese Experiment Module – Pressurized Module and Japanese Remote Manipulator System. Discovery's launch is targeted for May 31. Photo credit: NASA/Kim Shiflett

CAPE CANAVERAL, Fla. -- On Launch Pad 39A at NASA's Kennedy Space Center, STS-124 Mission Specialist Mike Fossum follows the yellow steel path to the slidewire basket area after completing the simulated launch countdown, part of the launch dress rehearsal known as the terminal countdown demonstration test. The crew is practicing emergency egress from the 195-foot level of the fixed service structure. TCDT provides astronauts and ground crews with an opportunity to participate in various simulated countdown activities, including a simulated launch countdown, equipment familiarization and emergency egress training. On the STS-124 mission, the crew will deliver and install the Japanese Experiment Module – Pressurized Module and Japanese Remote Manipulator System. Discovery's launch is targeted for May 31. Photo credit: NASA/Kim Shiflett

KENNEDY SPACE CENTER, Fla. -- STS-88 Mission Commander Robert D. Cabana (left) and Pilot Frederick W. "Rick" Sturckow (right) are ready to leave Launch Pad 39A in the slidewire basket during an emergency egress exercise. Other crew members watch from behind. The crew are at KSC to participate in the Terminal Countdown Demonstration Test (TCDT) which includes mission familiarization activities, emergency egress training, and the simulated main engine cut-off exercise. Mission STS-88 is targeted for launch on Dec. 3, 1998. It is the first U.S. flight for the assembly of the International Space Station and will carry the Unity connecting module. Unity will be mated with the already orbiting Russian-built Zarya control module. The 12-day mission includes three planned spacewalks to connect power, data and utility lines and install exterior equipment

CAPE CANAVERAL, Fla. -- On Launch Pad 39A at NASA's Kennedy Space Center, STS-124 Mission Specialist Mike Fossum leads two other astronauts to the slidewire basket area after completing the simulated launch countdown, part of the launch dress rehearsal known as the terminal countdown demonstration test. The crew is practicing emergency egress from the 195-foot level of the fixed service structure. TCDT provides astronauts and ground crews with an opportunity to participate in various simulated countdown activities, including a simulated launch countdown, equipment familiarization and emergency egress training. On the STS-124 mission, the crew will deliver and install the Japanese Experiment Module – Pressurized Module and Japanese Remote Manipulator System. Discovery's launch is targeted for May 31. Photo credit: NASA/Kim Shiflett

CAPE CANAVERAL, Fla. -- On Launch Pad 39A at NASA's Kennedy Space Center, STS-124 Mission Specialists Karen Nyberg (left) and Ron Garan have reached the slidewire baskets on the 195-foot level of the fixed service structure. The baskets are used for emergency egress, part of the launch dress rehearsal known as the terminal countdown demonstration test. TCDT provides astronauts and ground crews with an opportunity to participate in various simulated countdown activities, including a simulated launch countdown, equipment familiarization and emergency egress training. On the STS-124 mission, the crew will deliver and install the Japanese Experiment Module – Pressurized Module and Japanese Remote Manipulator System. Discovery's launch is targeted for May 31. Photo credit: NASA/Kim Shiflett

KENNEDY SPACE CENTER, Fla. -- In the slidewire basket bunker area of Launch Pad 39A, STS-118 Mission Specialist Barbara R. Morgan is introduced to the press during a media interview before the crew's morning training activities in the terminal countdown demonstration test, or TCDT. Morgan is a teacher-turned-astronaut whose association with NASA began more than 20 years ago. TCDT activities include M-113 training, payload familiarization, the emergency egress training at the pad and a simulated launch countdown. The mission is the 22nd flight to the International Space Station and Space Shuttle Endeavour will carry a payload including the S5 truss, a SPACEHAB module and external stowage platform 3. STS-118 is targeted for launch on Aug. 7. Photo credit: NASA/Ken Thornsley

KENNEDY SPACE CENTER, Fla. -- Standing in a slidewire basket at KSC’s Launch Pad 39A is STS-89 Mission Specialist James Reilly, Ph.D. The seven astronauts of STS-89 assigned to the eighth Shuttle-Mir docking flight are completing Terminal Countdown Demonstration Test (TCDT) activities at Kennedy Space Center. A dress rehearsal for launch, the TCDT includes emergency egress training at the launch pad and culminates with a simulated countdown. STS-89 Mission Specialist Andrew Thomas, Ph.D, will transfer to the Russian Space Station Mir and succeed David Wolf, M.D., who will return to Earth aboard Endeavour. The Space Shuttle Endeavour is undergoing preparations for liftoff, scheduled for Jan. 22. Dr. Thomas will live and work on Mir until June

STS-92 Mission Specialists Koichi Wakata and Michael Lopez-Alegria pause on the tarmac after their arrival aboard the T-38 jet aircraft in the background. They and the rest of the crew are at KSC to take part in Terminal Countdown Demonstration Test (TCDT) activities. The TCDT includes emergency egress training from the orbiter and pad, plus a simulated countdown. The fifth mission to the International Space Station, STS-92 will carry the Integrated Truss Structure Z1, the first of the planned 10 trusses on the Space Station, and the third Pressurized Mating Adapter. The Z1 will allow the first U.S. solar arrays on a future flight to be temporarily installed on Unity for early power. PMA-3 will provide a Shuttle docking port for the solar array installation on the sixth ISS flight and Lab installation on the seventh ISS flight. STS-92 is scheduled to launch Oct. 5 from launch Pad 39A. It will be the 100th flight in the Shuttle program

KENNEDY SPACE CENTER, FLA. -- During Terminal Countdown Demonstration Test (TCDT) activities at Launch Pad 39A, the Mission STS-117 crew members take time to speak to the media during a question-and-answer session. From the left are Commander Rick Sturckow, Pilot Lee Archambault, and Mission Specialists Patrick Forrester, Steven Swanson, Danny Olivas and James Reilly. The TCDT also includes M-113 armored personnel carrier training, pad emergency egress training and a simulated launch countdown. The mission payload aboard Space Shuttle Atlantis is the S3/S4 integrated truss structure, along with a third set of solar arrays and batteries. The crew of six astronauts will install the truss to continue assembly of the International Space Station. Photo credit: NASA/Kim Shiflett

KENNEDY SPACE CENTER, FLA. -- During Terminal Countdown Demonstration Test (TCDT) activities at Launch Pad 39A, the Mission STS-117 crew members speak to the media during a question-and-answer session. From the left are Commander Rick Sturckow, Pilot Lee Archambault, and Mission Specialists Patrick Forrester, Steven Swanson, Danny Olivas and James Reilly. The TCDT also includes M-113 armored personnel carrier training, pad emergency egress training and a simulated launch countdown. The mission payload aboard Space Shuttle Atlantis is the S3/S4 integrated truss structure, along with a third set of solar arrays and batteries. The crew of six astronauts will install the truss to continue assembly of the International Space Station. Photo credit: NASA/Kim Shiflett

CAPE CANAVERAL, Fla. - In the Operations and Checkout Building at NASA's Kennedy Space Center in Florida, STS-131 Commander Alan Poindexter verifies that his helmet is functioning properly. The members of space shuttle Discovery's STS-131 crew put on their launch-and-entry suits before heading to the Astrovan for the ride to Launch Pad 39A. The crew is participating in the Terminal Countdown Demonstration Test, or TCDT, a dress rehearsal for launch. TCDT includes training on the emergency egress systems at the launch pad, driving practice of the M-113 armored personnel carrier and a simulated launch countdown. The crew will deliver the multi-purpose logistics module Leonard, filled with resupply stowage platforms and science racks, to the International Space Station. STS-131, targeted for launch on April 5, will be the 33rd shuttle mission to the station and the 131st shuttle mission overall. For information on the STS-131 mission and crew, visit http:__www.nasa.gov_mission_pages_shuttle_shuttlemissions_sts131_index.htm. Photo credit: NASA_Kim Shiflett

CAPE CANAVERAL, Fla. - In the Operations and Checkout Building at NASA's Kennedy Space Center in Florida, STS-131 Mission Specialist Rick Mastracchio suits up for his third practice countdown. The members of space shuttle Discovery's STS-131 crew put on their launch-and-entry suits before heading to the Astrovan for the ride to Launch Pad 39A. The crew is participating in the Terminal Countdown Demonstration Test, or TCDT, a dress rehearsal for launch. TCDT includes training on the emergency egress systems at the launch pad, driving practice of the M-113 armored personnel carrier and a simulated launch countdown. The crew will deliver the multi-purpose logistics module Leonard, filled with resupply stowage platforms and science racks, to the International Space Station. STS-131, targeted for launch on April 5, will be the 33rd shuttle mission to the station and the 131st shuttle mission overall. For information on the STS-131 mission and crew, visit http:__www.nasa.gov_mission_pages_shuttle_shuttlemissions_sts131_index.htm. Photo credit: NASA_Kim Shiflett

CAPE CANAVERAL, Fla. - In the Operations and Checkout Building at NASA's Kennedy Space Center in Florida, STS-131 Commander Alan Poindexter appears enthusiastic about the opportunity to board Discovery. The members of space shuttle Discovery's STS-131 crew put on their launch-and-entry suits before heading to the Astrovan for the ride to Launch Pad 39A. The crew is participating in the Terminal Countdown Demonstration Test, or TCDT, a dress rehearsal for launch. TCDT includes training on the emergency egress systems at the launch pad, driving practice of the M-113 armored personnel carrier and a simulated launch countdown. The crew will deliver the multi-purpose logistics module Leonard, filled with resupply stowage platforms and science racks, to the International Space Station. STS-131, targeted for launch on April 5, will be the 33rd shuttle mission to the station and the 131st shuttle mission overall. For information on the STS-131 mission and crew, visit http:__www.nasa.gov_mission_pages_shuttle_shuttlemissions_sts131_index.htm. Photo credit: NASA_Kim Shiflett

KENNEDY SPACE CENTER, Fla. -- On the slidewire basket bunker area of Launch Pad 39A, the STS-118 crew greets the media before the crew's morning training activities in the terminal countdown demonstration test, or TCDT. From left are Commander Scott Kelly, Pilot Charlie Hobaugh and Mission Specialists Alvin Drew, Rick Mastracchio, Dave Williams, Barbara R. Morgan and Tracy Caldwell. Williams represents the Canadian Space Agency. Morgan joined NASA's Teacher in Space program in 1985 and was selected as an astronaut in 1998. TCDT activities include M-113 training, payload familiarization, the emergency egress training at the pad and a simulated launch countdown. The mission is the 22nd flight to the International Space Station and Space Shuttle Endeavour will carry a payload including the S5 truss, a SPACEHAB module and external stowage platform 3. STS-118 is targeted for launch on Aug. 7. NASA/George Shelton

KENNEDY SPACE CENTER, FLA. -- During Terminal Countdown Demonstration Test (TCDT) activities at Launch Pad 39A, the Mission STS-117 crew members speak to the media during a question-and-answer session. From the left are Mission Specialists James Reilly, Danny Olivas, Steven Swanson and Patrick Forrester, Pilot Lee Archambault and Commander Rick Sturckow, along with NASA Public Affairs Specialist Jessica Rye. The TCDT also includes M-113 armored personnel carrier training, pad emergency egress training and a simulated launch countdown. The mission payload aboard Space Shuttle Atlantis is the S3/S4 integrated truss structure, along with a third set of solar arrays and batteries. The crew of six astronauts will install the truss to continue assembly of the International Space Station. Photo credit: NASA/Kim Shiflett

CAPE CANAVERAL, Fla. - In the Operations and Checkout Building at NASA's Kennedy Space Center in Florida, STS-131 Mission Specialist Rick Mastracchio verifies that his helmet is functioning properly. The members of space shuttle Discovery's STS-131 crew put on their launch-and-entry suits before heading to the Astrovan for the ride to Launch Pad 39A. The crew is participating in the Terminal Countdown Demonstration Test, or TCDT, a dress rehearsal for launch. TCDT includes training on the emergency egress systems at the launch pad, driving practice of the M-113 armored personnel carrier and a simulated launch countdown. The crew will deliver the multi-purpose logistics module Leonard, filled with resupply stowage platforms and science racks, to the International Space Station. STS-131, targeted for launch on April 5, will be the 33rd shuttle mission to the station and the 131st shuttle mission overall. For information on the STS-131 mission and crew, visit http:__www.nasa.gov_mission_pages_shuttle_shuttlemissions_sts131_index.htm. Photo credit: NASA_Kim Shiflett

CAPE CANAVERAL, Fla. - In the Operations and Checkout Building at NASA's Kennedy Space Center in Florida, STS-131 Pilot James P. Dutton Jr. verifies that his helmet is functioning properly. The members of space shuttle Discovery's STS-131 crew put on their launch-and-entry suits before heading to the Astrovan for the ride to Launch Pad 39A. The crew is participating in the Terminal Countdown Demonstration Test, or TCDT, a dress rehearsal for launch. TCDT includes training on the emergency egress systems at the launch pad, driving practice of the M-113 armored personnel carrier and a simulated launch countdown. The crew will deliver the multi-purpose logistics module Leonard, filled with resupply stowage platforms and science racks, to the International Space Station. STS-131, targeted for launch on April 5, will be the 33rd shuttle mission to the station and the 131st shuttle mission overall. For information on the STS-131 mission and crew, visit http:__www.nasa.gov_mission_pages_shuttle_shuttlemissions_sts131_index.htm. Photo credit: NASA_Kim Shiflett

KENNEDY SPACE CENTER, Fla. -- On the slidewire basket bunker area of Launch Pad 39A, the STS-118 crew talks to the media before the crew's morning training activities in the terminal countdown demonstration test, or TCDT. At right, Mission Specialist Tracy Caldwell has the microphone. The others, from left, are Commander Scott Kelly, Pilot Charlie Hobaugh and Mission Specialists Alvin Drew, Rick Mastracchio, Dave Williams and Barbara Morgan. Williams represents the Canadian Space Agency. Morgan joined NASA's Teacher in Space program in 1985 and was selected as an astronaut in 1998. TCDT activities include M-113 training, payload familiarization, the emergency egress training at the pad and a simulated launch countdown. The mission is the 22nd flight to the International Space Station and Space Shuttle Endeavour will carry a payload including the S5 truss, a SPACEHAB module and external stowage platform 3. STS-118 is targeted for launch on Aug. 7. NASA/George Shelton

KENNEDY SPACE CENTER, FLA. -- During Terminal Countdown Demonstration Test (TCDT) activities at Launch Pad 39A, Mission STS-117 Commander Rick Sturckow (left) speaks to the media during a question-and-answer session. To his left are Pilot Lee Archambault, and Mission Specialists Patrick Forrester, Steven Swanson, Danny Olivas and James Reilly. The TCDT also includes M-113 armored personnel carrier training, pad emergency egress training and a simulated launch countdown. The mission payload aboard Space Shuttle Atlantis is the S3/S4 integrated truss structure, along with a third set of solar arrays and batteries. The crew of six astronauts will install the truss to continue assembly of the International Space Station. Photo credit: NASA/Kim Shiflett

KENNEDY SPACE CENTER, Fla. -- Standing in a slidewire basket at KSC’s Launch Pad 39A are, left to right, STS-89 Mission Specialists Bonnie Dunbar, Ph.D., Salizhan Sharipov of the Russian Space Agency, and Andrew Thomas, Ph.D. The seven astronauts assigned to the eighth Shuttle-Mir docking flight are completing Terminal Countdown Demonstration Test (TCDT) activities. A dress rehearsal for launch, the TCDT includes emergency egress training at the launch pad and culminates with a simulated countdown. STS-89 Mission Specialist Dr. Thomas will transfer to the Russian Space Station Mir and succeed David Wolf, M.D., who will return to Earth aboard Endeavour. The Space Shuttle Endeavour is undergoing preparations for liftoff, scheduled for Jan. 22. Dr. Thomas will live and work on Mir until June

KENNEDY SPACE CENTER, Fla. -- The smiling STS-118 crew walks toward the Astrovan that will take them to Launch Pad 39A for a simulated launch countdown. From left are Mission Specialists Barbara R. Morgan and Rick Mastracchio, Pilot Charlie Hobaugh, Mission Specialists Dave Williams and Tracy Caldwell, and Commander Scott Kelly. Morgan joined NASA's Teacher in Space program in 1985 and was selected as an astronaut in 1998. The countdown concludes the terminal countdown demonstration test, or TCDT. The STS-118 crew has been at Kennedy for the TCDT activities that also include M-113 training, payload familiarization and emergency egress training at the pad. The mission is the 22nd flight to the International Space Station and Space Shuttle Endeavour will carry a payload including the S5 truss, a SPACEHAB module and external stowage platform 3. STS-118 is targeted for launch on Aug. 7. Photo credit: NASA/George Shelton

KENNEDY SPACE CENTER, FLA. -- During Terminal Countdown Demonstration Test (TCDT) activities at Launch Pad 39A, the Mission STS-117 crew members speak to the media during a question-and-answer session. From the left are Commander Rick Sturckow, Pilot Lee Archambault, and Mission Specialists Patrick Forrester, Steven Swanson, Danny Olivas and James Reilly. The TCDT also includes M-113 armored personnel carrier training, pad emergency egress training and a simulated launch countdown. The mission payload aboard Space Shuttle Atlantis is the S3/S4 integrated truss structure, along with a third set of solar arrays and batteries. The crew of six astronauts will install the truss to continue assembly of the International Space Station. Photo credit: NASA/Kim Shiflett

KENNEDY SPACE CENTER, Fla. -- The STS-118 crew heads into the Astrovan that will take them to Launch Pad 39A for a simulated launch countdown. First in is Commander Scott Kelly. Following, right to left, are Pilot Charlie Hobaugh and Mission Specialists Tracy Caldwell, Dave Williams, Rick Mastracchio, teacher-turned-astronaut Barbara R. Morgan and Alvin Drew. The countdown concludes the terminal countdown demonstration test, or TCDT. The STS-118 crew has been at Kennedy for the TCDT activities that also include M-113 training, payload familiarization and emergency egress training at the pad. The mission is the 22nd flight to the International Space Station and Space Shuttle Endeavour will carry a payload including the S5 truss, a SPACEHAB module and external stowage platform 3. STS-118 is targeted for launch on Aug. 7. Photo credit: NASA/George Shelton

KENNEDY SPACE CENTER, Fla. -- The STS-118 crew walks toward the Astrovan that will take them to Launch Pad 39A for a simulated launch countdown. From left are Mission Specialists Barbara R. Morgan and Rick Mastracchio, Pilot Charlie Hobaugh, Mission Specialists Dave Williams and Tracy Caldwell, and Commander Scott Kelly. Morgan joined NASA's Teacher in Space program in 1985 and was selected as an astronaut in 1998. The countdown concludes the terminal countdown demonstration test, or TCDT. The STS-118 crew has been at Kennedy for the TCDT activities that also include M-113 training, payload familiarization and emergency egress training at the pad. The mission is the 22nd flight to the International Space Station and Space Shuttle Endeavour will carry a payload including the S5 truss, a SPACEHAB module and external stowage platform 3. STS-118 is targeted for launch on Aug. 7. Photo credit: NASA/George Shelton

STS-92 Mission Specialists Koichi Wakata and Michael Lopez-Alegria pause on the tarmac after their arrival aboard the T-38 jet aircraft in the background. They and the rest of the crew are at KSC to take part in Terminal Countdown Demonstration Test (TCDT) activities. The TCDT includes emergency egress training from the orbiter and pad, plus a simulated countdown. The fifth mission to the International Space Station, STS-92 will carry the Integrated Truss Structure Z1, the first of the planned 10 trusses on the Space Station, and the third Pressurized Mating Adapter. The Z1 will allow the first U.S. solar arrays on a future flight to be temporarily installed on Unity for early power. PMA-3 will provide a Shuttle docking port for the solar array installation on the sixth ISS flight and Lab installation on the seventh ISS flight. STS-92 is scheduled to launch Oct. 5 from launch Pad 39A. It will be the 100th flight in the Shuttle program

CAPE CANAVERAL, Fla. - In the Operations and Checkout Building at NASA's Kennedy Space Center in Florida, STS-131 Mission Specialist Stephanie Wilson seems pleased with the fit of her spacesuit. The members of space shuttle Discovery's STS-131 crew put on their launch-and-entry suits before heading to the Astrovan for the ride to Launch Pad 39A. The crew is participating in the Terminal Countdown Demonstration Test, or TCDT, a dress rehearsal for launch. TCDT includes training on the emergency egress systems at the launch pad, driving practice of the M-113 armored personnel carrier and a simulated launch countdown. The crew will deliver the multi-purpose logistics module Leonard, filled with resupply stowage platforms and science racks, to the International Space Station. STS-131, targeted for launch on April 5, will be the 33rd shuttle mission to the station and the 131st shuttle mission overall. For information on the STS-131 mission and crew, visit http:__www.nasa.gov_mission_pages_shuttle_shuttlemissions_sts131_index.htm. Photo credit: NASA_Kim Shiflett

KENNEDY SPACE CENTER, Fla. -- Standing in a slidewire basket at KSC’s Launch Pad 39A are, left to right, STS-89 Pilot Joe Edwards Jr. and Commander Terrence Wilcutt. The seven astronauts assigned to the eighth Shuttle-Mir docking flight are completing Terminal Countdown Demonstration Test (TCDT) activities. A dress rehearsal for launch, the TCDT includes emergency egress training at the launch pad and culminates with a simulated countdown. STS-89 Mission Specialist Andrew Thomas, Ph.D., will transfer to the Russian Space Station Mir and succeed David Wolf, M.D., who will return to Earth aboard Endeavour. The Space Shuttle Endeavour is undergoing preparations for liftoff, scheduled for Jan. 22. Dr. Thomas will live and work on Mir until June

CAPE CANAVERAL, Fla. - In the Operations and Checkout Building at NASA's Kennedy Space Center in Florida, STS-131 Mission Specialist Clayton Anderson adjusts his helmet. The members of space shuttle Discovery's STS-131 crew put on their launch-and-entry suits before heading to the Astrovan for the ride to Launch Pad 39A. The crew is participating in the Terminal Countdown Demonstration Test, or TCDT, a dress rehearsal for launch. TCDT includes training on the emergency egress systems at the launch pad, driving practice of the M-113 armored personnel carrier and a simulated launch countdown. The crew will deliver the multi-purpose logistics module Leonard, filled with resupply stowage platforms and science racks, to the International Space Station. STS-131, targeted for launch on April 5, will be the 33rd shuttle mission to the station and the 131st shuttle mission overall. For information on the STS-131 mission and crew, visit http:__www.nasa.gov_mission_pages_shuttle_shuttlemissions_sts131_index.htm. Photo credit: NASA_Kim Shiflett