CAPE CANAVERAL, Fla. – STS-127 Mission Specialist Dave Wolf takes the wheel of the M-113 armored personnel carrier. Driving the M-113 is part of the training on emergency egress procedures. The crew members of space shuttle Endeavour's STS-127 mission are taking turns driving the M-113. An M-113 will be available to transport the crew to safety in the event of a contingency on the pad before their launch. The crew is at NASA's Kennedy Space Center for a launch dress rehearsal called the terminal countdown demonstration test, or TCDT, which includes the emergency egress training and equipment familiarization. The STS-127 mission is the final of three flights dedicated to the assembly of the Japanese Kibo laboratory complex. Endeavour's launch is targeted for June 13. Photo credit: NASA/Kim Shiflett

CAPE CANAVERAL, Fla. – STS-127 Pilot Doug Hurley smiles after practicing driving the M-113 armored personnel carrier. The crew members of space shuttle Endeavour's STS-127 mission will each practice driving the M-113 in turn as part of their training on emergency egress procedures. An M-113 will be available to transport the crew to safety in the event of a contingency on the pad before their launch. The crew is at NASA's Kennedy Space Center for a launch dress rehearsal called the terminal countdown demonstration test, or TCDT, which includes the emergency egress training and equipment familiarization. The STS-127 mission is the final of three flights dedicated to the assembly of the Japanese Kibo laboratory complex. Endeavour's launch is targeted for June 13. Photo credit: NASA/Kim Shiflett

CAPE CANAVERAL, Fla. – STS-127 Commander Mark Polansky smiles after practicing driving the M-113 armored personnel carrier. The crew members of space shuttle Endeavour's STS-127 mission will each practice driving the M-113 in turn as part of their training on emergency egress procedures. An M-113 will be available to transport the crew to safety in the event of a contingency on the pad before their launch. The crew is at NASA's Kennedy Space Center for a launch dress rehearsal called the terminal countdown demonstration test, or TCDT, which includes the emergency egress training and equipment familiarization. The STS-127 mission is the final of three flights dedicated to the assembly of the Japanese Kibo laboratory complex. Endeavour's launch is targeted for June 13. Photo credit: NASA/Kim Shiflett

CAPE CANAVERAL, Fla. – STS-127 Mission Specialist Tom Marshburn takes his turn driving the M-113 armored personnel carrier, which is part of the training on emergency egress procedures. The crew members of space shuttle Endeavour's STS-127 mission are taking turns driving the M-113. An M-113 will be available to transport the crew to safety in the event of a contingency on the pad before their launch. The crew is at NASA's Kennedy Space Center for a launch dress rehearsal called the terminal countdown demonstration test, or TCDT, which includes the emergency egress training and equipment familiarization. The STS-127 mission is the final of three flights dedicated to the assembly of the Japanese Kibo laboratory complex. Endeavour's launch is targeted for June 13. Photo credit: NASA/Kim Shiflett

CAPE CANAVERAL, Fla. – STS-127 Mission Specialist Tim Kopra is happy to have successfully driven the M-113 armored personnel carrier, which is part of the training on emergency egress procedures. The crew members of space shuttle Endeavour's STS-127 mission are taking turns driving the M-113. An M-113 will be available to transport the crew to safety in the event of a contingency on the pad before their launch. The crew is at NASA's Kennedy Space Center for a launch dress rehearsal called the terminal countdown demonstration test, or TCDT, which includes the emergency egress training and equipment familiarization. The STS-127 mission is the final of three flights dedicated to the assembly of the Japanese Kibo laboratory complex. Endeavour's launch is targeted for June 13. Photo credit: NASA/Kim Shiflett

CAPE CANAVERAL, Fla. – STS-127 Commander Mark Polansky takes his turn driving the M-113 armored personnel carrier, which is part of the training on emergency egress procedures. The crew members of space shuttle Endeavour's STS-127 mission are taking turns driving the M-113. An M-113 will be available to transport the crew to safety in the event of a contingency on the pad before their launch. The crew is at NASA's Kennedy Space Center for a launch dress rehearsal called the terminal countdown demonstration test, or TCDT, which includes the emergency egress training and equipment familiarization. The STS-127 mission is the final of three flights dedicated to the assembly of the Japanese Kibo laboratory complex. Endeavour's launch is targeted for June 13. Photo credit: NASA/Kim Shiflett

CAPE CANAVERAL, Fla. – STS-127 Mission Specialist Christopher Cassidy is ready to take the wheel to practice driving the M-113 armored personnel carrier, which is part of the training on emergency egress procedures. The crew members of space shuttle Endeavour's STS-127 mission are taking turns driving the M-113. An M-113 will be available to transport the crew to safety in the event of a contingency on the pad before their launch. The crew is at NASA's Kennedy Space Center for a launch dress rehearsal called the terminal countdown demonstration test, or TCDT, which includes the emergency egress training and equipment familiarization. The STS-127 mission is the final of three flights dedicated to the assembly of the Japanese Kibo laboratory complex. Endeavour's launch is targeted for June 13. Photo credit: NASA/Kim Shiflett

CAPE CANAVERAL, Fla. – STS-127 Mission Specialist Julie Payette takes her turn practice driving the M-113 armored personnel carrier, which is part of the training on emergency egress procedures. Payette represents the Canadian Space Agency. Behind her is Pilot Doug Hurley. The crew members of space shuttle Endeavour's STS-127 mission are taking turns driving the M-113. An M-113 will be available to transport the crew to safety in the event of a contingency on the pad before their launch. The crew is at NASA's Kennedy Space Center for a launch dress rehearsal called the terminal countdown demonstration test, or TCDT, which includes the emergency egress training and equipment familiarization. The STS-127 mission is the final of three flights dedicated to the assembly of the Japanese Kibo laboratory complex. Endeavour's launch is targeted for June 13. Photo credit: NASA/Kim Shiflett

CAPE CANAVERAL, Fla. – STS-127 Mission Specialist Tim Kopra practices driving the M-113 armored personnel carrier, which is part of the training on emergency egress procedures. Other crew members are seated behind him and will take their turns at driving the M-113. An M-113 will be available to transport the crew to safety in the event of a contingency on the pad before their launch. The crew is at NASA's Kennedy Space Center for a launch dress rehearsal called the terminal countdown demonstration test, or TCDT, which includes the emergency egress training and equipment familiarization. The STS-127 mission is the final of three flights dedicated to the assembly of the Japanese Kibo laboratory complex. Endeavour's launch is targeted for June 13. Photo credit: NASA/Kim Shiflett

CAPE CANAVERAL, Fla. – STS-127 Mission Specialist Christopher Cassidy practices driving the M-113 armored personnel carrier, which is part of the training on emergency egress procedures. Other crew members seated behind him are Mission Specialist Julie Payette, Dave Wolf, Tom Marshburn and Pilot Doug Hurley, who will take their turns at driving the M-113. An M-113 will be available to transport the crew to safety in the event of a contingency on the pad before their launch. The crew is at NASA's Kennedy Space Center for a launch dress rehearsal called the terminal countdown demonstration test, or TCDT, which includes the emergency egress training and equipment familiarization. The STS-127 mission is the final of three flights dedicated to the assembly of the Japanese Kibo laboratory complex. Endeavour's launch is targeted for June 13. Photo credit: NASA/Kim Shiflett

CAPE CANAVERAL, Fla. – STS-127 Mission Specialist Dave Wolf poses for a photograph after driving the M-113 armored personnel carrier, which is part of the training on emergency egress procedures. The crew members of space shuttle Endeavour's STS-127 mission are taking turns driving the M-113. An M-113 will be available to transport the crew to safety in the event of a contingency on the pad before their launch. The crew is at NASA's Kennedy Space Center for a launch dress rehearsal called the terminal countdown demonstration test, or TCDT, which includes the emergency egress training and equipment familiarization. The STS-127 mission is the final of three flights dedicated to the assembly of the Japanese Kibo laboratory complex. Endeavour's launch is targeted for June 13. Photo credit: NASA/Kim Shiflett

CAPE CANAVERAL, Fla. – STS-127 Mission Specialist Julie Payette smiles after her success in driving the M-113 armored personnel carrier, which is part of the training on emergency egress procedures. Payette represents the Canadian Space Agency. The crew members of space shuttle Endeavour's STS-127 mission are taking turns driving the M-113. An M-113 will be available to transport the crew to safety in the event of a contingency on the pad before their launch. The crew is at NASA's Kennedy Space Center for a launch dress rehearsal called the terminal countdown demonstration test, or TCDT, which includes the emergency egress training and equipment familiarization. The STS-127 mission is the final of three flights dedicated to the assembly of the Japanese Kibo laboratory complex. Endeavour's launch is targeted for June 13. Photo credit: NASA/Kim Shiflett

CAPE CANAVERAL, Fla. – STS-127 Mission Specialist Tom Marshburn smiles after successfully driving the M-113 armored personnel carrier, which is part of the training on emergency egress procedures. The crew members of space shuttle Endeavour's STS-127 mission are taking turns driving the M-113. An M-113 will be available to transport the crew to safety in the event of a contingency on the pad before their launch. The crew is at NASA's Kennedy Space Center for a launch dress rehearsal called the terminal countdown demonstration test, or TCDT, which includes the emergency egress training and equipment familiarization. The STS-127 mission is the final of three flights dedicated to the assembly of the Japanese Kibo laboratory complex. Endeavour's launch is targeted for June 13. Photo credit: NASA/Kim Shiflett

CAPE CANAVERAL, Fla. – STS-127 Pilot Doug Hurley drives the M-113 armored personnel carrier, which is part of the training on emergency egress procedures. The crew members of space shuttle Endeavour's STS-127 mission are taking turns driving the M-113, which will be available to transport the crew to safety in the event of a contingency on the pad before their launch. The crew is at NASA's Kennedy Space Center for a launch dress rehearsal called the terminal countdown demonstration test, or TCDT, which includes the emergency egress training and equipment familiarization. The STS-127 mission is the final of three flights dedicated to the assembly of the Japanese Kibo laboratory complex. Endeavour's launch is targeted for June 13. Photo credit: NASA/Kim Shiflett

CAPE CANAVERAL, Fla. – The STS-127 crew members sit in the M-113 armored personnel carrier for instructions on driving the M-113 as part of their training on emergency egress procedures. On the left are Commander Mark Polansky and Mission Specialists Tom Marshburn, Julie Payette and Dave Wolf (behind Payette). On the right are Mission Specialist Christopher Cassidy, Pilot Doug Hurley and Mission Specialist Tim Kopra. The crew members of space shuttle Endeavour's STS-127 mission will each practice driving the M-113. An M-113 will be available to transport the crew to safety in the event of a contingency on the pad before their launch. The crew is at NASA's Kennedy Space Center for a launch dress rehearsal called the terminal countdown demonstration test, or TCDT, which includes the emergency egress training and equipment familiarization. The STS-127 mission is the final of three flights dedicated to the assembly of the Japanese Kibo laboratory complex. Endeavour's launch is targeted for June 13. Photo credit: NASA/Kim Shiflett

KENNEDY SPACE CENTER, FLA. -- At Launch Complex 39, STS-117 Mission Specialist Steven Swanson is helmeted and ready to practice driving an M-113 armored personnel carrier. The astronauts on the STS-117 crew are participating in M-113 armored personnel carrier training during Terminal Countdown Demonstration Test (TCDT) activities, a dress rehearsal for their launch, targeted for March 15. The M-113 could be used to move the crew away from the launch pad quickly in the event of an emergency. The TCDT also includes 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 station. Photo credit: NASA/Kim Shiflett

KENNEDY SPACE CENTER, FLA. -- At Launch Complex 39, STS-117 Pilot Lee Archambault is helmeted and ready to practice driving an M-113 armored personnel carrier. The astronauts on the STS-117 crew are participating in M-113 armored personnel carrier training during Terminal Countdown Demonstration Test (TCDT) activities, a dress rehearsal for their launch, targeted for March 15. The M-113 could be used to move the crew away from the launch pad quickly in the event of an emergency. The TCDT also includes 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 station. Photo credit: NASA/Kim Shiflett

KENNEDY SPACE CENTER, FLA. -- At Launch Complex 39, members of the STS-117 crew are instructed in the operation of an M-113 armored personnel carrier by astronaut rescue team leader Capt. George Hoggard (left). The astronauts on the STS-117 crew are participating in M-113 armored personnel carrier training during Terminal Countdown Demonstration Test (TCDT) activities, a dress rehearsal for their launch, targeted for March 15. The M-113 could be used to move the crew away from the launch pad quickly in the event of an emergency. The TCDT also includes 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 station. Photo credit: NASA/Kim Shiflett

KENNEDY SPACE CENTER, FLA. -- At Launch Complex 39, STS-117 Mission Specialist James Reilly is helmeted and ready to practice driving an M-113 armored personnel carrier. The astronauts on the STS-117 crew are participating in M-113 armored personnel carrier training during Terminal Countdown Demonstration Test (TCDT) activities, a dress rehearsal for their launch, targeted for March 15. The M-113 could be used to move the crew away from the launch pad quickly in the event of an emergency. The TCDT also includes 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 station. Photo credit: NASA/Kim Shiflett

KENNEDY SPACE CENTER, FLA. -- At Launch Complex 39, STS-117 Mission Specialist Patrick Forrester is helmeted and ready to practice driving an M-113 armored personnel carrier. The astronauts on the STS-117 crew are participating in M-113 armored personnel carrier training during Terminal Countdown Demonstration Test (TCDT) activities, a dress rehearsal for their launch, targeted for March 15. The M-113 could be used to move the crew away from the launch pad quickly in the event of an emergency. The TCDT also includes 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 station. Photo credit: NASA/Kim Shiflett

KENNEDY SPACE CENTER, FLA. -- At Launch Complex 39, STS-117 Mission Specialist Danny Olivas is helmeted and ready to practice driving an M-113 armored personnel carrier. The astronauts on the STS-117 crew are participating in M-113 armored personnel carrier training during Terminal Countdown Demonstration Test (TCDT) activities, a dress rehearsal for their launch, targeted for March 15. The M-113 could be used to move the crew away from the launch pad quickly in the event of an emergency. The TCDT also includes 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 station. Photo credit: NASA/Kim Shiflett

KENNEDY SPACE CENTER, FLA. -- At Launch Complex 39, STS-117 Commander Rick Sturckow signals that he is ready to practice driving an M-113 armored personnel carrier. The astronauts on the STS-117 crew are participating in M-113 armored personnel carrier training during Terminal Countdown Demonstration Test (TCDT) activities, a dress rehearsal for their launch, targeted for March 15. The M-113 could be used to move the crew away from the launch pad quickly in the event of an emergency. The TCDT also includes 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 station. Photo credit: NASA/Kim Shiflett

KENNEDY SPACE CENTER, FLA. -- At Launch Complex 39, members of the STS-117 crew are instructed in the operation of an M-113 armored personnel carrier by the astronaut rescue team. The astronauts on the STS-117 crew are participating in M-113 armored personnel carrier training during Terminal Countdown Demonstration Test (TCDT) activities, a dress rehearsal for their launch, targeted for March 15. The M-113 could be used to move the crew away from the launch pad quickly in the event of an emergency. The TCDT also includes 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 station. Photo credit: NASA/Kim Shiflett

KENNEDY SPACE CENTER, FLA. -- At Launch Complex 39, STS-117 Mission Specialist Patrick Forrester (right) waits his turn to practice driving an M-113 armored personnel carrier as fellow crew members look on. The astronauts on the STS-117 crew are participating in M-113 armored personnel carrier training during Terminal Countdown Demonstration Test (TCDT) activities, a dress rehearsal for their launch, targeted for March 15. The M-113 could be used to move the crew away from the launch pad quickly in the event of an emergency. The TCDT also includes 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 station. Photo credit: NASA/Kim Shiflett

STS-89 Commander Terrence Wilcutt gets ready to train in an M-113 armored personnel carrier as part of Terminal Countdown Demonstration Test (TCDT) activities. The TCDT is held at KSC prior to each Space Shuttle flight to provide crews with an opportunity to participate in simulated countdown activities. Standing inside the M-113 vehicle is Wilcutt while George Hoggard, a training officer with KSC Fire Services, sits atop the armored personnel carrier. The STS-89 mission will be the eighth docking of the Space Shuttle with the Russian Space Station Mir. After docking, STS-89 Mission Specialist Andrew Thomas, Ph.D., will transfer to the space station, succeeding David Wolf, M.D., who will return to Earth aboard Endeavour. Dr. Thomas will live and work on Mir until June. STS-89 is scheduled for a Jan. 22 liftoff at 9:48 p.m

KENNEDY SPACE CENTER, FLA. -- STS-120 Mission Specialist Doug Wheelock gets ready in the driver's seat for driving practice in the M-113 armored personnel carrier. The M-113 is part of emergency exit procedures from Launch Pad 39A. Behind him, at right, is Pilot George Zamka. The training is part of terminal countdown demonstration test, or TCDT, activities the crew is undertaking at NASA's Kennedy Space Center. The TCDT also includes equipment familiarization and a simulated launch countdown. Mission STS-120, which will carry the Italian-built U.S. Node 2 to the International Space Station, is targeted for launch on Oct. 23. Photo credit: NASA/Kim Shiflett

KENNEDY SPACE CENTER, Fla. -- STS-118 Commander Scott Kelly stands inside an M-113 armored personnel carrier before his driving session as part of emergency exit training. He and other crew members are at Kennedy for the Terminal Countdown Demonstration Test (TCDT), a dress rehearsal for launch. TCDT activities include the M-113 training, payload familiarization, emergency egress training at the pad and a simulated launch countdown. The STS-118 payload aboard Space Shuttle Endeavour includes the S5 truss, a SPACEHAB module and external stowage platform 3. The mission is the 22nd flight to the International Space Station and is targeted for launch on Aug.7. NASA/George Shelton

KENNEDY SPACE CENTER, FLA. -- STS-120 Commander Pamela Melroy is ready for her turn at driving practice in the M-113 armored personnel carrier. The M-113 is part of emergency exit procedures from Launch Pad 39A. The training is part of terminal countdown demonstration test, or TCDT, activities the crew is undertaking at NASA's Kennedy Space Center. The TCDT also includes equipment familiarization and a simulated launch countdown. Mission STS-120, which will carry the Italian-built U.S. Node 2 to the International Space Station, is targeted for launch on Oct. 23. Photo credit: NASA/Kim Shiflett

KENNEDY SPACE CENTER, Fla. -- STS-118 Commander Scott Kelly practices driving an M-113 armored personnel carrier with fellow crew members Tracy Caldwell, Alvin Drew and Dave Williams, all mission specialists, as passengers. They are at Kennedy for the Terminal Countdown Demonstration Test (TCDT), a dress rehearsal for launch. TCDT activities include the M-113 training, payload familiarization, emergency egress training at the pad and a simulated launch countdown. The STS-118 payload aboard Space Shuttle Endeavour includes the S5 truss, a SPACEHAB module and external stowage platform 3. The mission is the 22nd flight to the International Space Station and is targeted for launch on Aug.7. NASA/George Shelton

KENNEDY SPACE CENTER, Fla. -- STS-118 Pilot Charlie Hobaugh stands inside an M-113 armored personnel carrier before his driving session as part of emergency exit training. He and other crew members are at Kennedy for the Terminal Countdown Demonstration Test (TCDT), a dress rehearsal for launch. TCDT activities include the M-113 training, payload familiarization, emergency egress training at the pad and a simulated launch countdown. The STS-118 payload aboard Space Shuttle Endeavour includes the S5 truss, a SPACEHAB module and external stowage platform 3. The mission is the 22nd flight to the International Space Station and is targeted for launch on Aug.7. NASA/George Shelton

KENNEDY SPACE CENTER, Fla. -- STS-118 Mission Specialist Alvin Drew stands inside an M-113 armored personnel carrier before his driving session, as part of emergency exit training. He and other crew members are at Kennedy for the Terminal Countdown Demonstration Test (TCDT), a dress rehearsal for launch. TCDT activities include the M-113 training, payload familiarization, emergency egress training at the pad and a simulated launch countdown. The STS-118 payload aboard Space Shuttle Endeavour includes the S5 truss, a SPACEHAB module and external stowage platform 3. The mission is the 22nd flight to the International Space Station and is targeted for launch on Aug.7. NASA/George Shelton

KENNEDY SPACE CENTER, Fla. -- STS-118 Pilot Charlie Hobaugh practices driving an M-113 armored personnel carrier with passenger (at left) Tracy Caldwell, mission specialist. They and other crew members are at Kennedy for the Terminal Countdown Demonstration Test (TCDT), a dress rehearsal for launch. TCDT activities include the M-113 training, payload familiarization, emergency egress training at the pad and a simulated launch countdown. The STS-118 payload aboard Space Shuttle Endeavour includes the S5 truss, a SPACEHAB module and external stowage platform 3. The mission is the 22nd flight to the International Space Station and is targeted for launch on Aug.7. NASA/George Shelton

KENNEDY SPACE CENTER, FLA. -- STS-120 Commander Pamela Melroy poses for another photo after driving practice in the M-113 armored personnel carrier. The M-113 is part of emergency exit procedures from Launch Pad 39A. The training is part of terminal countdown demonstration test, or TCDT, activities the crew is undertaking at NASA's Kennedy Space Center. The TCDT also includes equipment familiarization and a simulated launch countdown. Mission STS-120, which will carry the Italian-built U.S. Node 2 to the International Space Station, is targeted for launch on Oct. 23. Photo credit: NASA/Kim Shiflett

KENNEDY SPACE CENTER, FLA. -- STS-120 Mission Specialist Paolo Nespoli, who represents the European Space Agency, gets ready in the driver's seat for driving practice in the M-113 armored personnel carrier. The M-113 is part of emergency exit procedures from Launch Pad 39A. The training is part of terminal countdown demonstration test, or TCDT, activities the crew is undertaking at NASA's Kennedy Space Center. The TCDT also includes equipment familiarization and a simulated launch countdown. Mission STS-120, which will carry the Italian-built U.S. Node 2 to the International Space Station, is targeted for launch on Oct. 23. Photo credit: NASA/Kim Shiflett

KENNEDY SPACE CENTER, FLA. -- STS-120 Pamela Melroy (front) is ready for training on the M-113 armored personnel carrier, part of emergency egress training. The training is part of terminal countdown demonstration test, or TCDT, activities the crew is undertaking at NASA's Kennedy Space Center. The TCDT also includes equipment familiarization and a simulated launch countdown. Mission STS-120, which will carry the Italian-built U.S. Node 2 to the International Space Station, is targeted for launch on Oct. 23. Photo credit: NASA/Kim Shiflett

KENNEDY SPACE CENTER, FLA. -- Mission STS-117 crew members receive emergency egress instruction at Launch Pad 39A during Terminal Countdown Demonstration Test activities. From the left in front are Pilot Lee Archambault, Mission Specialists Danny Olivas and Steven Swanson, Commander Rick Sturckow and Mission Specialist Patrick Forrester. Directly behind Olivas is Mission Specialist James Reilly. At right is a partial view of the M-113 armored personnel carrier. 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. -- STS-116 Commander Mark Polansky is ready for his turn at driving the M-113 armored personnel carrier. The mission crew is at KSC for terminal countdown demonstration test (TCDT) activities that are preparation for launch. The M-113 could be used to move the crew quickly away from the launch pad in the event of an emergency. Behind Polansky is Mission Specialist Robert Curbeam. The STS-116 mission is No. 20 to the International Space Station and construction flight 12A.1. The mission payload is the SPACEHAB module, the P5 integrated truss structure and other key components. Launch is scheduled for no earlier than Dec. 7. Photo credit: NASA/Kim Shiflett

KENNEDY SPACE CENTER, FLA. -- STS-116 Mission Specialist Joan Higginbotham is helmeted and ready to practice driving the M-113 armored personnel carrier. The mission crew is at KSC for terminal countdown demonstration test (TCDT) activities that are preparation for launch. The M-113 could be used to move the crew quickly away from the launch pad in the event of an emergency. In the background is Mission Specialist Nicholas Patrick. The STS-116 mission is No. 20 to the International Space Station and construction flight 12A.1. The mission payload is the SPACEHAB module, the P5 integrated truss structure and other key components. Launch is scheduled for no earlier than Dec. 7. Photo credit: NASA/Kim Shiflett

CAPE CANAVERAL, Fla. – At NASA's Kennedy Space Center in Florida, STS-128 Pilot Kevin Ford has completed his turn at driving an M-113 armored personnel carrier. The crew members of space shuttle Discovery's STS-128 mission are taking turns driving the M-113, which will be available to transport the crew to safety in the event of a contingency on the pad before their launch. 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, as well as a simulated launch countdown. Launch of Discovery is targeted for late August. Photo credit: NASA/Kim Shiflett

CAPE CANAVERAL, Fla. – At NASA's Kennedy Space Center in Florida, STS-128 Mission Specialist Nicole Stott drives an M-113 armored personnel carrier. Behind Stott are (from left) Commander Rick Sturckow and Pilot Kevin Ford, who already took their turns at driving the M-113. 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, as well as a simulated launch countdown. Launch of Discovery is targeted for late August. Photo credit: NASA/Kim Shiflett

CAPE CANAVERAL, Fla. – At NASA's Kennedy Space Center in Florida, STS-128 Mission Specialist Patrick Forrester takes his turn driving an M-113 armored personnel carrier. At left is Mission Specialist John "Danny" Olivas. 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, as well as a simulated launch countdown. Launch of Discovery is targeted for late August. Photo credit: NASA/Kim Shiflett

CAPE CANAVERAL, Fla. – At NASA's Kennedy Space Center in Florida, STS-128 Mission Specialist Jose Hernandez has completed his turn driving an M-113 armored personnel carrier. 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, as well as a simulated launch countdown. Launch of Discovery is targeted for late August. Photo credit: NASA/Kim Shiflett

CAPE CANAVERAL, Fla. – At NASA's Kennedy Space Center in Florida, STS-128 Mission Specialist Jose Hernandez takes his turn driving an M-113 armored personnel carrier. 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, as well as a simulated launch countdown. Launch of Discovery is targeted for late August. Photo credit: NASA/Kim Shiflett

CAPE CANAVERAL, Fla. – At NASA's Kennedy Space Center in Florida, STS-128 Mission Specialist John "Danny" Olivas has completed his turn driving an M-113 armored personnel carrier. 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, as well as a simulated launch countdown. Launch of Discovery is targeted for late August. Photo credit: NASA/Kim Shiflett

CAPE CANAVERAL, Fla. – At NASA's Kennedy Space Center in Florida, STS-128 Mission Specialist Christer Fuglesang takes his turn driving an M-113 armored personnel carrier. Fuglesang represents the European 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, as well as a simulated launch countdown. Launch of Discovery is targeted for late August. Photo credit: NASA/Kim Shiflett

CAPE CANAVERAL, Fla. – At NASA's Kennedy Space Center in Florida, STS-128 Mission Specialist John "Danny" Olivas takes his turn driving an M-113 armored personnel carrier. 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, as well as a simulated launch countdown. Launch of Discovery is targeted for late August. Photo credit: NASA/Kim Shiflett

CAPE CANAVERAL, Fla. – At NASA's Kennedy Space Center in Florida, STS-128 Mission Specialist Christer Fuglesang has completed his turn driving an M-113 armored personnel carrier. Fuglesang represents the European 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, as well as a simulated launch countdown. Launch of Discovery is targeted for late August. Photo credit: NASA/Kim Shiflett

CAPE CANAVERAL, Fla. – At NASA's Kennedy Space Center in Florida, STS-128 Mission Specialist Patrick Forrester has completed his turn at driving an M-113 armored personnel carrier. 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, as well as a simulated launch countdown. Launch of Discovery is targeted for late August. Photo credit: NASA/Kim Shiflett

CAPE CANAVERAL, Fla. – At NASA's Kennedy Space Center in Florida, STS-128 Mission Specialist Nicole Stott has completed her turn at driving an M-113 armored personnel carrier. 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, as well as a simulated launch countdown. Launch of Discovery is targeted for late August. Photo credit: NASA/Kim Shiflett

CAPE CANAVERAL, Fla. - The STS-125 crew members listen to instructions for driving the M-113 armored personnel carrier. From left are Mission Specialists John Grunsfeld, Megan McArthur, Michael Good, Mike Massimino and Gregory C. Johnson. The crew members of space shuttle Atlantis' STS-125 mission will each practice driving the M-113 in turn as part of their training on emergency egress procedures. An M-113 will be available to transport the crew to safety in the event of a contingency on the pad before their launch. The crew is at NASA's Kennedy Space Center for a dress launch rehearsal called the terminal countdown demonstration test, or TCDT. It provides astronauts and ground crews with an opportunity to participate in various simulated countdown activities, including equipment familiarization, emergency training and a simulated launch countdown. The STS-125 mission aboard space shuttle Atlantis to service NASA’s Hubble Space Telescope is targeted to launch Oct. 10. Photo credit: NASA/Kim Shiflett

CAPE CANAVERAL, Fla. - STS-125 Commander Scott Altman is ready to practice driving the M-113 armored personnel carrier. The crew members of space shuttle Atlantis' STS-125 mission will each practice driving the M-113 in turn as part of their training on emergency egress procedures. An M-113 will be available to transport the crew to safety in the event of a contingency on the pad before their launch. The crew is at NASA's Kennedy Space Center for a dress launch rehearsal called the terminal countdown demonstration test, or TCDT. It provides astronauts and ground crews with an opportunity to participate in various simulated countdown activities, including equipment familiarization, emergency training and a simulated launch countdown. The STS-125 mission aboard space shuttle Atlantis to service NASA’s Hubble Space Telescope is targeted to launch Oct. 10. Photo credit: NASA/Kim Shiflett

CAPE CANAVERAL, Fla. - The STS-125 crew members listen to instructions for driving the M-113 armored personnel carrier. From left are Mission Specialists Megan McArthur, Mike Massimino and Michael Good. The crew members of space shuttle Atlantis' STS-125 mission will each practice driving the M-113 in turn as part of their training on emergency egress procedures. An M-113 will be available to transport the crew to safety in the event of a contingency on the pad before their launch. The crew is at NASA's Kennedy Space Center for a dress launch rehearsal called the terminal countdown demonstration test, or TCDT. It provides astronauts and ground crews with an opportunity to participate in various simulated countdown activities, including equipment familiarization, emergency training and a simulated launch countdown. The STS-125 mission aboard space shuttle Atlantis to service NASA’s Hubble Space Telescope is targeted to launch Oct. 10. Photo credit: NASA/Kim Shiflett

CAPE CANAVERAL, Fla. - STS-125 Mission Specialist Megan McArthur practices driving the M-113 armored personnel carrier. Other crew members are behind her. The crew members of space shuttle Atlantis' STS-125 mission will each practice driving the M-113 in turn as part of their training on emergency egress procedures. An M-113 will be available to transport the crew to safety in the event of a contingency on the pad before their launch. The crew is at NASA's Kennedy Space Center for a dress launch rehearsal called the terminal countdown demonstration test, or TCDT. It provides astronauts and ground crews with an opportunity to participate in various simulated countdown activities, including equipment familiarization, emergency training and a simulated launch countdown. The STS-125 mission aboard space shuttle Atlantis to service NASA’s Hubble Space Telescope is targeted to launch Oct. 10. Photo credit: NASA/Kim Shiflett

CAPE CANAVERAL, Fla. - STS-125 Pilot Gregory C. Johnson practices driving the M-113 armored personnel carrier. Behind him are other crew members. The crew members of space shuttle Atlantis' STS-125 mission will each practice driving the M-113 in turn as part of their training on emergency egress procedures. An M-113 will be available to transport the crew to safety in the event of a contingency on the pad before their launch. The crew is at NASA's Kennedy Space Center for a dress launch rehearsal called the terminal countdown demonstration test, or TCDT. It provides astronauts and ground crews with an opportunity to participate in various simulated countdown activities, including equipment familiarization, emergency training and a simulated launch countdown. The STS-125 mission aboard space shuttle Atlantis to service NASA’s Hubble Space Telescope is targeted to launch Oct. 10. Photo credit: NASA/Kim Shiflett

CAPE CANAVERAL, Fla. - STS-125 Mission Specialist John Grunsfeld is ready to practice driving the M-113 armored personnel carrier. The crew members of space shuttle Atlantis' STS-125 mission will each practice driving the M-113 in turn as part of their training on emergency egress procedures. An M-113 will be available to transport the crew to safety in the event of a contingency on the pad before their launch. The crew is at NASA's Kennedy Space Center for a dress launch rehearsal called the terminal countdown demonstration test, or TCDT. It provides astronauts and ground crews with an opportunity to participate in various simulated countdown activities, including equipment familiarization, emergency training and a simulated launch countdown. The STS-125 mission aboard space shuttle Atlantis to service NASA’s Hubble Space Telescope is targeted to launch Oct. 10. Photo credit: NASA/Kim Shiflett

CAPE CANAVERAL, Fla. - STS-125 Pilot Gregory C. Johnson is ready to practice driving the M-113 armored personnel carrier. The crew members of space shuttle Atlantis' STS-125 mission will each practice driving the M-113 in turn as part of their training on emergency egress procedures. An M-113 will be available to transport the crew to safety in the event of a contingency on the pad before their launch. The crew is at NASA's Kennedy Space Center for a dress launch rehearsal called the terminal countdown demonstration test, or TCDT. It provides astronauts and ground crews with an opportunity to participate in various simulated countdown activities, including equipment familiarization, emergency training and a simulated launch countdown. The STS-125 mission aboard space shuttle Atlantis to service NASA’s Hubble Space Telescope is targeted to launch Oct. 10. Photo credit: NASA/Kim Shiflett

KENNEDY SPACE CENTER, FLA. -- STS-116 Mission Specialist Robert Curbeam practices driving the M-113 armored personnel carrier. The mission crew is at KSC for terminal countdown demonstration test (TCDT) activities that are preparation for launch. The M-113 could be used to move the crew quickly away from the launch pad in the event of an emergency. At left of Polansky is Capt. George Hoggard, who is astronaut rescue team leader. In the back of the M-113, at right, is Commander Mark Polansky. The STS-116 mission is No. 20 to the International Space Station and construction flight 12A.1. The mission payload is the SPACEHAB module, the P5 integrated truss structure and other key components. Launch is scheduled for no earlier than Dec. 7. Photo credit: NASA/Kim Shiflett

CAPE CANAVERAL, Fla. - An STS-125 crew member affixes a mission patch to the inside of the M-113 armored personnel carrier the crew practiced driving.The crew members of space shuttle Atlantis' STS-125 mission each practiced driving the M-113 in turn as part of their training on emergency egress procedures. An M-113 will be available to transport the crew to safety in the event of a contingency on the pad before their launch. The crew is at NASA's Kennedy Space Center for a dress launch rehearsal called the terminal countdown demonstration test, or TCDT. It provides astronauts and ground crews with an opportunity to participate in various simulated countdown activities, including equipment familiarization, emergency training and a simulated launch countdown. The STS-125 mission aboard space shuttle Atlantis to service NASA’s Hubble Space Telescope is targeted to launch Oct. 10. Photo credit: NASA/Kim Shiflett

CAPE CANAVERAL, Fla. - STS-125 Mission Specialist Mike Massimino is ready to practice driving the M-113 armored personnel carrier. The crew members of space shuttle Atlantis' STS-125 mission will each practice driving the M-113 in turn as part of their training on emergency egress procedures. An M-113 will be available to transport the crew to safety in the event of a contingency on the pad before their launch. The crew is at NASA's Kennedy Space Center for a dress launch rehearsal called the terminal countdown demonstration test, or TCDT. It provides astronauts and ground crews with an opportunity to participate in various simulated countdown activities, including equipment familiarization, emergency training and a simulated launch countdown. The STS-125 mission aboard space shuttle Atlantis to service NASA’s Hubble Space Telescope is targeted to launch Oct. 10. Photo credit: NASA/Kim Shiflett

CAPE CANAVERAL, Fla. - STS-125 Mission Specialist Michael Good practices driving the M-113 armored personnel carrier. Other crew members are behind him. The crew members of space shuttle Atlantis' STS-125 mission will each practice driving the M-113 in turn as part of their training on emergency egress procedures. An M-113 will be available to transport the crew to safety in the event of a contingency on the pad before their launch. The crew is at NASA's Kennedy Space Center for a dress launch rehearsal called the terminal countdown demonstration test, or TCDT. It provides astronauts and ground crews with an opportunity to participate in various simulated countdown activities, including equipment familiarization, emergency training and a simulated launch countdown. The STS-125 mission aboard space shuttle Atlantis to service NASA’s Hubble Space Telescope is targeted to launch Oct. 10. Photo credit: NASA/Kim Shiflett

CAPE CANAVERAL, Fla. - STS-125 Mission Specialist Andrew Feustel is ready to practice driving the M=113 armored personnel carrier. The crew members of space shuttle Atlantis' STS-125 mission will each practice driving the M-113 in turn as part of their training on emergency egress procedures. An M-113 will be available to transport the crew to safety in the event of a contingency on the pad before their launch. The crew is at NASA's Kennedy Space Center for a dress launch rehearsal called the terminal countdown demonstration test, or TCDT. It provides astronauts and ground crews with an opportunity to participate in various simulated countdown activities, including equipment familiarization, emergency training and a simulated launch countdown. The STS-125 mission aboard space shuttle Atlantis to service NASA’s Hubble Space Telescope is targeted to launch Oct. 10. Photo credit: NASA/Kim Shiflett

CAPE CANAVERAL, Fla. - STS-125 Mission Specialist Mike Massimino practices driving the M-113 armored personnel carrier. Behind him are other crew members. The crew members of space shuttle Atlantis' STS-125 mission will each practice driving the M-113 in turn as part of their training on emergency egress procedures. An M-113 will be available to transport the crew to safety in the event of a contingency on the pad before their launch. The crew is at NASA's Kennedy Space Center for a dress launch rehearsal called the terminal countdown demonstration test, or TCDT. It provides astronauts and ground crews with an opportunity to participate in various simulated countdown activities, including equipment familiarization, emergency training and a simulated launch countdown. The STS-125 mission aboard space shuttle Atlantis to service NASA’s Hubble Space Telescope is targeted to launch Oct. 10. Photo credit: NASA/Kim Shiflett

CAPE CANAVERAL, Fla. - STS-125 Mission Specialist Michael Good is ready to practice driving the M-113 armored personnel carrier. The crew members of space shuttle Atlantis' STS-125 mission will each practice driving the M-113 in turn as part of their training on emergency egress procedures. An M-113 will be available to transport the crew to safety in the event of a contingency on the pad before their launch. The crew is at NASA's Kennedy Space Center for a dress launch rehearsal called the terminal countdown demonstration test, or TCDT. It provides astronauts and ground crews with an opportunity to participate in various simulated countdown activities, including equipment familiarization, emergency training and a simulated launch countdown. The STS-125 mission aboard space shuttle Atlantis to service NASA’s Hubble Space Telescope is targeted to launch Oct. 10. Photo credit: NASA/Kim Shiflett

CAPE CANAVERAL, Fla. - STS-125 Mission Specialist Megan McArthur is ready to practice driving the M-113 armored personnel carrier. The crew members of space shuttle Atlantis' STS-125 mission will each practice driving the M-113 in turn as part of their training on emergency egress procedures. An M-113 will be available to transport the crew to safety in the event of a contingency on the pad before their launch. The crew is at NASA's Kennedy Space Center for a dress launch rehearsal called the terminal countdown demonstration test, or TCDT. It provides astronauts and ground crews with an opportunity to participate in various simulated countdown activities, including equipment familiarization, emergency training and a simulated launch countdown. The STS-125 mission aboard space shuttle Atlantis to service NASA’s Hubble Space Telescope is targeted to launch Oct. 10. Photo credit: NASA/Kim Shiflett

CAPE CANAVERAL, Fla. – At NASA's Kennedy Space Center in Florida, STS-128 Pilot Kevin Ford drives an M-113 armored personnel carrier. At far left is Commander Rick Sturckow. Other crew members will take their turns at driving the M-113. The crew members of space shuttle Discovery's STS-128 mission are taking turns driving the M-113, which will be available to transport the crew to safety in the event of a contingency on the pad before their launch. 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, as well as a simulated launch countdown. Launch of le Discovery is targeted for late August. Photo credit: NASA/Kim Shiflett

CAPE CANAVERAL, Fla. - STS-125 Commander Scott Altman practices driving the M-113 armored personnel carrier. Behind him are other crew members. The crew members of space shuttle Atlantis' STS-125 mission will each practice driving the M-113 in turn as part of their training on emergency egress procedures. An M-113 will be available to transport the crew to safety in the event of a contingency on the pad before their launch. The crew is at NASA's Kennedy Space Center for a dress launch rehearsal called the terminal countdown demonstration test, or TCDT. It provides astronauts and ground crews with an opportunity to participate in various simulated countdown activities, including equipment familiarization, emergency training and a simulated launch countdown. The STS-125 mission aboard space shuttle Atlantis to service NASA’s Hubble Space Telescope is targeted to launch Oct. 10. Photo credit: NASA/Kim Shiflett

KENNEDY SPACE CENTER, FLA. -- STS-116 Mission Specialist Christer Fuglesang practices driving the M-113 armored personnel carrier. Fuglesang represents the European Space Agency. The mission crew is at KSC for terminal countdown demonstration test (TCDT) activities that are preparation for launch. The M-113 could be used to move the crew quickly away from the launch pad in the event of an emergency. At left of Fuglesang is Capt. George Hoggard, who is astronaut rescue team leader. Other crew members on the M-113, behind Hoggard, are Mission Specialist Sunita Williams, Pilot William Oefelein and Nicholas Patrick. In the background is Mission Specialist Joan Higginbotham. The STS-116 mission is No. 20 to the International Space Station and construction flight 12A.1. The mission payload is the SPACEHAB module, the P5 integrated truss structure and other key components. Launch is scheduled for no earlier than Dec. 7. Photo credit: NASA/Kim Shiflett

CAPE CANAVERAL, Fla. - STS-125 Mission Specialist John Grunsfeld practices driving the M-113 armored personnel carrier. Other crew members are behind him. The crew members of space shuttle Atlantis' STS-125 mission will each practice driving the M-113 in turn as part of their training on emergency egress procedures. An M-113 will be available to transport the crew to safety in the event of a contingency on the pad before their launch. The crew is at NASA's Kennedy Space Center for a dress launch rehearsal called the terminal countdown demonstration test, or TCDT. It provides astronauts and ground crews with an opportunity to participate in various simulated countdown activities, including equipment familiarization, emergency training and a simulated launch countdown. The STS-125 mission aboard space shuttle Atlantis to service NASA’s Hubble Space Telescope is targeted to launch Oct. 10. Photo credit: NASA/Kim Shiflett

KENNEDY SPACE CENTER, FLA. -- The STS-113 crew pause for a photo after test drives in the M-113 armored personnel carrier behind them. From left are Mission Specialist Michael Lopez-Alegria, Pilot Paul Lockhart, Commander James Wetherbee and Mission Specialist John Herrington. Driving the M-113 is part of emergency egress training at the pad, one of the Terminal Countdown Demonstration Test activities in preparation for launch. The TCDT also includes a simulated launch countdown. The primary payloads on mission STS-113 are the first port truss segment, P1, and the Crew and Equipment Translation Aid (CETA) Cart B. Once delivered, the P1 truss will remain stowed until flight 12A.1 in 2003 when it will be attached to the central truss segment, S0, on the Space Station. Also onboard Space Shuttle Endeavour will be the Expedition 6 crew who will replace Expedition 5, returning to Earth after 4 months.

KENNEDY SPACE CENTER, FLA. -- STS-120 Mission Specialist Daniel Tani is ready for his turn at driving the M-113 armored personnel carrier. The M-113 is part of emergency exit procedures from Launch Pad 39A. Behind him, at right, is Mission Specialist Paolo Nespoli, who represents the European Space Agency. The training is part of terminal countdown demonstration test, or TCDT, activities the crew is undertaking at NASA's Kennedy Space Center. The TCDT also includes equipment familiarization and a simulated launch countdown. Mission STS-120, which will carry the Italian-built U.S. Node 2 to the International Space Station, is targeted for launch on Oct. 23. Photo credit: NASA/Kim Shiflett

KENNEDY SPACE CENTER, FLA. -- STS-120 Pilot George Zamka practices driving the M-113 armored personnel carrier, part of emergency exit procedures from Launch Pad 39A. Alongside is the trainer. In the rear of the M-113 are Mission Specialists Daniel Tani, Commander Pamela Melroy and Mission Specialists Stephanie Wilson, Paolo Nespoli and Doug Wheelock. Nespoli represents the European Space Agency. The training is part of terminal countdown demonstration test, or TCDT, activities the crew is undertaking at NASA's Kennedy Space Center. The TCDT also includes equipment familiarization and a simulated launch countdown. Mission STS-120, which will carry the Italian-built U.S. Node 2 to the International Space Station, is targeted for launch on Oct. 23. Photo credit: NASA/Kim Shiflett

KENNEDY SPACE CENTER, FLA. -- After driving practice on the M-113 armored personnel carrier, the STS-120 crew pauses for a group photo. From left are Mission Specialists Scott Parazynski, Daniel Tani and Doug Wheelock, Commander Pamela Melroy, Mission Specialist Stephanie Wilson, Pilot George Zamka and Mission Specialist Paolo Nespoli, who represents the European Space Agency. The M-113 is part of emergency exit procedures from Launch Pad 39A. The training is part of terminal countdown demonstration test, or TCDT, activities the crew is undertaking at NASA's Kennedy Space Center. The TCDT also includes equipment familiarization and a simulated launch countdown. Mission STS-120, which will carry the Italian-built U.S. Node 2 to the International Space Station, is targeted for launch on Oct. 23. Photo credit: NASA/Kim Shiflett

CAPE CANAVERAL, Fla. -- At NASA's Kennedy Space Center in Florida, STS-133 Pilot Eric Boe prepares to practice driving an M-113 armored personnel carrier. Behind him is Commander Steve Lindsey. An M-113 is kept at the foot of the launch pad in case an emergency egress from the vicinity of the pad is needed, and training on the vehicle is part of the Terminal Countdown Demonstration Test (TCDT). TCDT provides each shuttle crew and launch team an opportunity to participate in various simulated activities, including equipment familiarization and a launch countdown. Space shuttle Discovery and its STS-133 crew will deliver the Permanent Multipurpose Module, packed with supplies and critical spare parts, as well as Robonaut 2, the dexterous humanoid astronaut helper, to the International Space Station. Launch is targeted for Nov. 1 at 4:40 p.m. For more information on the STS-133 mission, visit www.nasa.gov/mission_pages/shuttle/shuttlemissions/sts133/. Photo credit: NASA/Kim Shiflett

KENNEDY SPACE CENTER, FLA. -- STS-120 Mission Specialist Stephanie Wilson is ready for her turn at driving the M-113 armored personnel carrier. The M-113 is part of emergency exit procedures from Launch Pad 39A. Behind her are Mission Specialists Doug Wheelock, at left) and Paolo Nespoli, who represents the European Space Agency. The training is part of terminal countdown demonstration test, or TCDT, activities the crew is undertaking at NASA's Kennedy Space Center. The TCDT also includes equipment familiarization and a simulated launch countdown. Mission STS-120, which will carry the Italian-built U.S. Node 2 to the International Space Station, is targeted for launch on Oct. 23. Photo credit: NASA/Kim Shiflett

CAPE CANAVERAL, Fla. -- At NASA's Kennedy Space Center in Florida, STS-133 Mission Commander Steve Lindsey points out his crew's mission patch on an M-113 armored personnel carrier. An M-113 is kept at the foot of the launch pad in case an emergency egress from the vicinity of the pad is needed, and driving the vehicle is part of the Terminal Countdown Demonstration Test (TCDT). TCDT provides each shuttle crew and launch team an opportunity to participate in various simulated activities, including equipment familiarization and a launch countdown. Space shuttle Discovery and its STS-133 crew will deliver the Permanent Multipurpose Module, packed with supplies and critical spare parts, as well as Robonaut 2, the dexterous humanoid astronaut helper, to the International Space Station. Launch is targeted for Nov. 1 at 4:40 p.m. For more information on the STS-133 mission, visit www.nasa.gov/mission_pages/shuttle/shuttlemissions/sts133/. Photo credit: NASA/Kim Shiflett

CAPE CANAVERAL, Fla. -- At NASA's Kennedy Space Center in Florida, the STS-133 crew shares a light moment with Battalion Chief David Seymour, left, during training on the M-113 armored personnel carrier. An M-113 is kept at the foot of the launch pad in case an emergency egress from the vicinity of the pad is needed, and driving the vehicle is part of the Terminal Countdown Demonstration Test (TCDT). TCDT provides each shuttle crew and launch team an opportunity to participate in various simulated activities, including equipment familiarization and a launch countdown. Space shuttle Discovery and its STS-133 crew will deliver the Permanent Multipurpose Module, packed with supplies and critical spare parts, as well as Robonaut 2, the dexterous humanoid astronaut helper, to the International Space Station. Launch is targeted for Nov. 1 at 4:40 p.m. For more information on the STS-133 mission, visit www.nasa.gov/mission_pages/shuttle/shuttlemissions/sts133/. Photo credit: NASA/Kim Shiflett

KENNEDY SPACE CENTER, Fla. -- STS-118 Mission Specialist Barbara R. Morgan practices driving an M-113 armored personnel carrier as part of emergency exit training. Seen in the back, at left, are Commander Scott Kelly and Mission Specialists Tracy Caldwell and Alvin Drew. Morgan joined NASA's Teacher in Space program in 1985 and was selected as an astronaut in 1998. She and other crew members are at Kennedy for the Terminal Countdown Demonstration Test (TCDT), a dress rehearsal for launch. TCDT activities include the M-113 training, payload familiarization, emergency egress training at the pad and a simulated launch countdown. The STS-118 payload aboard Space Shuttle Endeavour includes the S5 truss, a SPACEHAB module and external stowage platform 3. The mission is the 22nd flight to the International Space Station and is targeted for launch on Aug.7. NASA/George Shelton

KENNEDY SPACE CENTER, FLA. -- STS-120 Mission Specialist Scott Parazynski is ready for his turn at driving the M-113 armored personnel carrier. The M-113 is part of emergency exit procedures from Launch Pad 39A. Behind Parazynski is Mission Specialist Paolo Nespoli, who represents the European Space Agency. The training is part of terminal countdown demonstration test, or TCDT, activities the crew is undertaking at NASA's Kennedy Space Center. The TCDT also includes equipment familiarization and a simulated launch countdown. Mission STS-120, which will carry the Italian-built U.S. Node 2 to the International Space Station, is targeted for launch on Oct. 23. Photo credit: NASA/Kim Shiflett

KENNEDY SPACE CENTER, FLA. -- Driven by Mission Specialist Daniel Tani, the M-113 armored personnel carrier moves through the underbrush near Launch Pad 39A. The M-113 is part of emergency exit procedures from Launch Pad 39A. Also in front is the trainer. In the rear are Mission Specialists Doug Wheelock, Scott Parazynski and Paolo Nespoli, who represents the European Space Agency. The training is part of terminal countdown demonstration test, or TCDT, activities the crew is undertaking at NASA's Kennedy Space Center. The TCDT also includes equipment familiarization and a simulated launch countdown. Mission STS-120, which will carry the Italian-built U.S. Node 2 to the International Space Station, is targeted for launch on Oct. 23. Photo credit: NASA/Kim Shiflett

KENNEDY SPACE CENTER, Fla. -- STS-118 Mission Specialist Alvin Drew practices driving an M-113 armored personnel carrier, with (at right) Mission Specialists Barbara R. Morgan and Dave Williams as passengers. Morgan joined NASA's Teacher in Space program in 1985 and was selected as an astronaut in 1998. Williams represents the Canadian Space Agency. They and other crew members are at Kennedy for the Terminal Countdown Demonstration Test (TCDT), a dress rehearsal for launch. TCDT activities include the M-113 training, payload familiarization, emergency egress training at the pad and a simulated launch countdown. The STS-118 payload aboard Space Shuttle Endeavour includes the S5 truss, a SPACEHAB module and external stowage platform 3. The mission is the 22nd flight to the International Space Station and is targeted for launch on Aug.7. NASA/George Shelton

KENNEDY SPACE CENTER, Fla. -- STS-118 Mission Specialist Tracy Caldwell is ready to take her turn at driving an M-113 armored personnel carrier as part of emergency exit training. Seen behind her at right is Mission Specialist Dave Williams, who represents the Canadian Space Agency. They and other crew members are at Kennedy for the Terminal Countdown Demonstration Test (TCDT), a dress rehearsal for launch. TCDT activities include the M-113 training, payload familiarization, emergency egress training at the pad and a simulated launch countdown. The STS-118 payload aboard Space Shuttle Endeavour includes the S5 truss, a SPACEHAB module and external stowage platform 3. The mission is the 22nd flight to the International Space Station and is targeted for launch on Aug.7. NASA/George Shelton

STS-89 Mission Specialist Andrew Thomas, Ph.D. gets ready to drive an M-113 armored personnel carrier as part of Terminal Countdown Demonstration Test (TCDT) activities. The TCDT is held at KSC prior to each Space Shuttle flight to provide crews with an opportunity to participate in simulated countdown activities. Standing inside the M-113 is Dr. Thomas while George Hoggard, a training officer with KSC Fire Services, sits atop the vehicle. The STS-89 mission will be the eighth docking of the Space Shuttle with the Russian Space Station Mir. After docking, Dr. Thomas will transfer to the space station, succeeding David Wolf, M.D., who will return to Earth aboard Endeavour. Dr. Thomas will live and work on Mir until June. STS-89 is scheduled for a Jan. 22 liftoff at 9:48 p.m

CAPE CANAVERAL, Fla. -- At NASA's Kennedy Space Center in Florida, STS-133 Commander Steve Lindsey prepares to drive the M-113 armored personnel carrier. An M-113 is kept at the foot of the launch pad in case an emergency egress from the vicinity of the pad is needed, and training on the vehicle is part of the Terminal Countdown Demonstration Test (TCDT). TCDT provides each shuttle crew and launch team an opportunity to participate in various simulated activities, including equipment familiarization and a launch countdown. Space shuttle Discovery and its STS-133 crew will deliver the Permanent Multipurpose Module, packed with supplies and critical spare parts, as well as Robonaut 2, the dexterous humanoid astronaut helper, to the International Space Station. Launch is targeted for Nov. 1 at 4:40 p.m. For more information on the STS-133 mission, visit www.nasa.gov/mission_pages/shuttle/shuttlemissions/sts133/. Photo credit: NASA/Kim Shiflett

KENNEDY SPACE CENTER, FLA. -- STS-120 Pilot George Zamka gets ready in the driver's seat for driving practice in the M-113 armored personnel carrier. The M-113 is part of emergency exit procedures from Launch Pad 39A. Behind Zamka, half hidden, is Mission Specialist Paolo Nespoli, who represents the European Space Agency. The training is part of terminal countdown demonstration test, or TCDT, activities the crew is undertaking at NASA's Kennedy Space Center. The TCDT also includes equipment familiarization and a simulated launch countdown. Mission STS-120, which will carry the Italian-built U.S. Node 2 to the International Space Station, is targeted for launch on Oct. 23. Photo credit: NASA/Kim Shiflett

KENNEDY SPACE CENTER, Fla. -- STS-118 Mission Specialist Rick Mastracchio practices driving an M-113 armored personnel carrier as part of emergency exit training. The astronauts seen behind him are Mission Specialists Alvin Drew, Barbara R. Morgan, Dave Williams (standing) and Tracy Caldwell. 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 the Terminal Countdown Demonstration Test (TCDT), a dress rehearsal for launch. TCDT activities include the M-113 training, payload familiarization, emergency egress training at the pad and a simulated launch countdown. The STS-118 payload aboard Space Shuttle Endeavour includes the S5 truss, a SPACEHAB module and external stowage platform 3. The mission is the 22nd flight to the International Space Station and is targeted for launch on Aug.7. NASA/George Shelton

KENNEDY SPACE CENTER, Fla. -- STS-118 Mission Specialist Tracy Caldwell practices driving an M-113 armored personnel carrier as part of emergency exit training. Seen in the back are Mission Specialist Alvin Drew, Pilot Charlie Hobaugh and educator astronaut and Mission Specialist Barbara R. Morgan. They and other crew members are at Kennedy for the Terminal Countdown Demonstration Test (TCDT), a dress rehearsal for launch. TCDT activities include the M-113 training, payload familiarization, emergency egress training at the pad and a simulated launch countdown. The STS-118 payload aboard Space Shuttle Endeavour includes the S5 truss, a SPACEHAB module and external stowage platform 3. The mission is the 22nd flight to the International Space Station and is targeted for launch on Aug.7. NASA/George Shelton

KENNEDY SPACE CENTER, Fla. -- STS-118 Mission Specialist Dave Williams, who represents the Canadian Space Agency, signals success after driving an M-113 armored personnel carrier as part of emergency exit training. Behind him are, at left, Pilot Charlie Hobaugh and, right, Mission Specialist Tracy Caldwell. They and other crew members are at Kennedy for the Terminal Countdown Demonstration Test (TCDT), a dress rehearsal for launch. TCDT activities include the M-113 training, payload familiarization, emergency egress training at the pad and a simulated launch countdown. The STS-118 payload aboard Space Shuttle Endeavour includes the S5 truss, a SPACEHAB module and external stowage platform 3. The mission is the 22nd flight to the International Space Station and is targeted for launch on Aug.7. NASA/George Shelton

KENNEDY SPACE CENTER, Fla. -- STS-118 Mission Specialist Rick Mastracchio gets ready to practice driving an M-113 armored personnel carrier as part of emergency exit training. Behind him, at right, is Mission Specialist Tracy Caldwell. They and other crew members are at Kennedy for the Terminal Countdown Demonstration Test (TCDT), a dress rehearsal for launch. TCDT activities include the M-113 training, payload familiarization, emergency egress training at the pad and a simulated launch countdown. The STS-118 payload aboard Space Shuttle Endeavour includes the S5 truss, a SPACEHAB module and external stowage platform 3. The mission is the 22nd flight to the International Space Station and is targeted for launch on Aug.7. NASA/George Shelton

KENNEDY SPACE CENTER, Fla. -- STS-118 Mission Specialist Barbara R. Morgan is ready to practice driving an M-113 armored personnel carrier as part of emergency exit training. Behind her at the rear are Mission Specialists (left) Tracy Caldwell and Dave Williams. Morgan joined NASA's Teacher in Space program in 1985 and was selected as an astronaut in 1998. She and other crew members are at Kennedy for the Terminal Countdown Demonstration Test (TCDT), a dress rehearsal for launch. TCDT activities include the M-113 training, payload familiarization, emergency egress training at the pad and a simulated launch countdown. The STS-118 payload aboard Space Shuttle Endeavour includes the S5 truss, a SPACEHAB module and external stowage platform 3. The mission is the 22nd flight to the International Space Station and is targeted for launch on Aug.7. NASA/George Shelton

KENNEDY SPACE CENTER, Fla. -- STS-118 Commander Scott Kelly practices driving an M-113 armored personnel carrier, as part of emergency exit training, with fellow crew members aboard. Behind Kelly is Mission Specialist Barbara R. Morgan. The crew is at Kennedy for the Terminal Countdown Demonstration Test (TCDT), a dress rehearsal for launch. TCDT activities include the M-113 training, payload familiarization, emergency egress training at the pad and a simulated launch countdown. The STS-118 payload aboard Space Shuttle Endeavour includes the S5 truss, a SPACEHAB module and external stowage platform 3. The mission is the 22nd flight to the International Space Station and is targeted for launch on Aug.7. NASA/George Shelton

KENNEDY SPACE CENTER, Fla. -- STS-118 Mission Specialist Dave Williams, who represents the Canadian Space Agency, gets ready to practice driving an M-113 armored personnel carrier as part of emergency exit training. Behind him is Mission Specialist Barbara R. Morgan. They and other crew members are at Kennedy for the Terminal Countdown Demonstration Test (TCDT), a dress rehearsal for launch. TCDT activities include the M-113 training, payload familiarization, emergency egress training at the pad and a simulated launch countdown. The STS-118 payload aboard Space Shuttle Endeavour includes the S5 truss, a SPACEHAB module and external stowage platform 3. The mission is the 22nd flight to the International Space Station and is targeted for launch on Aug.7. NASA/George Shelton

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-120 Pamela Melroy is ready for training on the M-113 armored personnel carrier, part of emergency egress training. Behind her Mission Specialist Paolo Nespoli looks on. Nespoli is with the European Space Agency. The training is part of terminal countdown demonstration test, or TCDT, activities the crew is undertaking at NASA's Kennedy Space Center. The TCDT also includes equipment familiarization and a simulated launch countdown. Mission STS-120, which will carry the Italian-built U.S. Node 2 to the International Space Station, is targeted for launch on Oct. 23. Photo credit: NASA/Kim Shiflett

KENNEDY SPACE CENTER, FLA. -- Mission STS-117 Pilot Lee Archambault sits in the cockpit of Space Shuttle Atlantis at Launch Pad 39A to participate in a simulated launch countdown that is 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. -- STS-110 Pilot Stephen Frick waits inside the M-113 armored personnel carrier to begin training on driving the vehicle, which is part of Terminal Countdown Demonstration Test activities. TCDT includes emergency egress training and a simulated launch countdown. The TCDT is held at KSC prior to each Space Shuttle flight. Scheduled for launch April 4, the 11-day mission will feature Shuttle Atlantis docking with the International Space Station (ISS) and delivering the S0 truss, the centerpiece-segment of the primary truss structure that will eventually extend over 300 feet

KENNEDY SPACE CENTER, FLA. -- STS-110 Mission Specialist Ellen Ochoa waits her turn at driving the M-113 armored personnel carrier, part of Terminal Countdown Demonstration Test activities. In the background, right, is Pilot Stephen Frick. TCDT includes emergency egress training and a simulated launch countdown. The TCDT is held at KSC prior to each Space Shuttle flight. Scheduled for launch April 4, the 11-day mission will feature Shuttle Atlantis docking with the International Space Station (ISS) and delivering the S0 truss, the centerpiece-segment of the primary truss structure that will eventually extend over 300 feet

KENNEDY SPACE CENTER, FLA. -- STS-120 Commander Pamela Melroy drives the M-113 armored personnel carrier near Launch Pad 39A as part of emergency exit procedures. Beside her in front is the trainer. In the rear are Mission Specialists Daniel Tani and Paolo Nespoli, who represents the European Space Agency. The training is part of terminal countdown demonstration test, or TCDT, activities the crew is undertaking at NASA's Kennedy Space Center. The TCDT also includes equipment familiarization and a simulated launch countdown. Mission STS-120, which will carry the Italian-built U.S. Node 2 to the International Space Station, is targeted for launch on Oct. 23. Photo credit: NASA/Kim Shiflett

KENNEDY SPACE CENTER, FLA. -- Mission STS-117 Commander Rick Sturckow sits in the cockpit of Space Shuttle Atlantis at Launch Pad 39A to participate in a simulated launch countdown that is part of the prelaunch preparations known as terminal demonstration countdown 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.

STS-84 Mission Specialist C. Michael Foale rides in an M-113 armored personnel carrier as part of the Terminal Countdown Demonstration Test (TCDT) activities. STS-84 aboard the Space Shuttle Atlantis will be the sixth docking of the Space Shuttle with the Russian Space Station Mir. After docking, Foale will transfer to the space station and become a member of the Mir 23 crew, replacing U.S. astronaut Jerry M. Linenger, who will return to Earth aboard Atlantis. Foale will live and work on Mir until mid-September when his replacement is expected to arrive on the STS-86 mission. STS-84 is targeted for a May 15 liftoff

KENNEDY SPACE CENTER, FLA. -- STS-116 Pilot William Oefelein wears his helmet in preparation for driving the M-113 armored personnel carrier. The mission crew is at KSC for terminal countdown demonstration test (TCDT) activities that are preparation for launch. The M-113 could be used to move the crew quickly away from the launch pad in the event of an emergency. Behind Oefelein, at right, are Mission Specialists Nicholas Patrick and Joan Higginbotham. The STS-116 mission is No. 20 to the International Space Station and construction flight 12A.1. The mission payload is the SPACEHAB module, the P5 integrated truss structure and other key components. Launch is scheduled for no earlier than Dec. 7. Photo credit: NASA/Kim Shiflett