On the level of the fixed service structure on Launch Pad 39A and Danny Olivas head for the slidewire baskets.

On the 195-foot level of the fixed service structure on Launch Pad 39A, STS-117 Mission Specialists James Reilly (front) and Danny Olivas head for the slidewire baskets. 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.