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