Practice the crew gathers on the level of the fixed service structure on Launch Pad 39B.

Following a simulated launch countdown and emergency egress practice, the STS-115 crew gathers on the 215-foot level of the fixed service structure on Launch Pad 39B. From left are Pilot Christopher Ferguson, Mission Specialists Heidemarie Stefanyshyn-Piper and Joseph Tanner, Commander Brent Jett, and Mission Specialists Steven MacLean and Daniel Burbank. MacLean is with the Canadian Space Agency. Behind them loom the top of Space Shuttle Atlantis' external tank and one of the solid rocket boosters. The TCDT is a prelaunch preparation for the mission that is scheduled to lift off in a window opening Aug. 27. During their 11-day mission to the International Space Station, the STS-115 crew will continue construction of the station and attach the payload elements, the Port 3/4 truss segment with its two large solar arrays. Photo credit: NASA/Cory Huston