(05/07/1998) --- During emergency egress training, STS-91 Mission Specialists Wendy B. Lawrence and Franklin Chang-Diaz, Ph.D., (giving a thumbs up) practice slidewire basket procedures on the 195-foot level of Launch Complex 39A. The training is part of Terminal Countdown Demonstration Test (TCDT) activities held at KSC prior to each Space Shuttle flight to provide crews with an opportunity to participate in simulated countdown scenarios. STS-91 is scheduled to be launched on June 2 with a launch window opening around 6:10 p.m. EDT. The mission will feature the ninth Shuttle docking with the Russian Space Station Mir, the first Mir docking for Discovery, the conclusion of Phase I of the joint U.S.-Russian International Space Station Program, and the first flight of the new Space Shuttle super lightweight external tank. The STS-91 flight crew also includes Mission Commander Charles Precourt; Pilot Dominic Gorie; and Mission Specialists Valery Ryumin, with the Russian Space Agency, and Janet Kavandi, Ph.D. Andrew Thomas, Ph.D., will be returning to Earth with the crew after living more than four months aboard Mir