On an upper level of the Pad 39A fixed service structure, the STS-118 crew listen to a trainer, at left, about using the emergency egress system. The crew members are, from left, Commander Scott Kelly, Mission Specialists Tracy Caldwell, Barbara R. Morgan, Dave Williams and Alvin Drew, Pilot Charlie Hobaugh and Mission Specialist Rick Mastracchio. Williams represents the Canadian Space Agency. Morgan joined NASA's Teacher in Space program in 1985 and was selected as an astronaut in 1998. The crew is at Kennedy for training activities in the terminal countdown demonstration test, or TCDT. TCDT activities include M-113 training, payload familiarization, the emergency egress training at the pad and a simulated launch countdown. The mission is the 22nd flight to the International Space Station and Space Shuttle Endeavour will carry a payload including the S5 truss, a SPACEHAB module and external stowage platform 3. STS-118 is targeted for launch on Aug. 7. NASA/George Shelton