Mission Specialists Jeff Williams and Jim Voss will have several tasks as part of the planned six and a half hour extravehicular activity, or EVA, this evening. They will inspect and then secure a U.S.-built cargo crane known as the Orbital replacement unit Transfer Device that originally was installed during a space walk on the STS-96 mission in June 1999. Williams and Voss then will complete assembly of a Russian cargo crane called Strela (Russian for "arrow") that was begun on a space walk during STS-96. Strela will be placed on the Pressurized Mating Adapter-1 that connects the Unity node to the Zarya control module in the same vicinity as the American crane.
The two space walkers then will turn their attention to replacing one of Unity's two early communication antennas. That antenna has been experiencing some problems. Williams and Voss then will move on to their final EVA task with the installation of eight handrails on the station's exterior. This is part of some get ahead work for two upcoming assembly flights -- STS-92 in late September and STS-97 in January 2001. The STS-92 crew will install the Z-1 truss structure, and the STS-97 crew will deliver the U.S. Laboratory module. If all activities go as planned, the space walk should conclude about 3:45 a.m. CDT. Monday. During tonight's EVA activity, Williams will be identifiable by red stripes on the arms and legs of his spacesuit while Voss' spacesuit will be solid white. Tonight's EVA will mark the 85th space walk in U.S. history and the fifth dedicated to assembly of the International Space Station. To date, Shuttle astronauts have performed almost 300 hours of EVAs (297 hours, 53 minutes). The duration of the four previous station assembly space walks is 29 hours, 17 minutes.
Atlantis is operating well with flight controllers reporting no problems of significance for any of the mission's activities. The shuttle and station are docked in an orbit with a high point of 209 statute miles and a low point of 203 statute miles, circling Earth every 91 minutes.