The STS-117 crew arrives at NASA's Kennedy Space Center to take part in the Terminal Countdown Demonstration Test (TCDT), a preparation for the launch March 15 to the International Space Station. Seen here is Mission Specialist Steven Swanson in a T-38 jet aircraft. The TCDT includes 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