STS-112 Commander Jeffrey Ashby drives the M-113 armored personnel carrier during Terminal Countdown Demonstration Test activities. At the far left is Mission Specialist Sandra Magnus. The TCDT also includes a simulated launch countdown. The mission aboard Space Shuttle Atlantis is scheduled to launch no earlier than Oct. 2, between 2 and 6 p.m. EDT. STS-112 is the 15th assembly mission to the International Space Station. Atlantis will be carrying the S1 Integrated Truss Structure, the first starboard truss segment. The S1 will be attached to the central truss segment, S0, during the 11-day mission.