Mission Specialists Sergei Konstantinovich Krikalev sit inside orbiter Endeavour during Terminal Countdown Demonstration Activities TCDT.

STS-88 Mission Specialists Sergei Konstantinovich Krikalev (left) and James H. Newman (right) sit inside orbiter Endeavour during Terminal Countdown Demonstration Activities (TCDT). The TCDT includes mission familiarization activities, emergency egress training, and the simulated main engine cut-off exercise. Mission STS-88 is targeted for launch on Dec. 3, 1998. It is the first U.S. flight for the assembly of the International Space Station and will carry the Unity connecting module. Unity will be mated with the already orbiting Russian-built Zarya control module. The 12-day mission includes three planned spacewalks to connect power, data and utility lines and install exterior equipment