(04/29/1999) --- In the white room, an environmental chamber, at Launch Pad 39B, STS-96 Mission Specialist Valery Ivanovich Tokarev, with the Russian Space Agency, gets help with equipment from Chris Menard, Jean Alexander and James Davis before entering the orbiter Discovery at Launch Pad 39B. The crew are taking part in Terminal Countdown Demonstration Test (TCDT) activities, which provide opportunities to inspect the mission payloads in the orbiter's payload bay, as well as simulated countdown exercises and emergency egress training. STS-96, scheduled for liftoff on May 20 at 9:32 a.m., is a logistics and resupply mission for the International Space Station, carrying such payloads as a Russian crane, the Strela; a U.S.-built crane; the Spacehab Oceaneering Space System Box (SHOSS), a logistics items carrier; and STARSHINE, a student-led experiment