MISSION CONTROL CENTER STATUS REPORT # 18 STS-69 Saturday, September 16, 1995, 5:30 AM CDT Astronauts Jim Voss and Mike Gernhardt floated out into Endeavour's cargo bay early this morning for a 6 1/2 hour spacewalk designed to test new thermal improvements made to their spacesuits and the tools and techniques which may be used one day in the assembly of the International Space Station. The spacewalk began at 3:20 a.m. Central, after Voss and Gernhardt breathed pure oxygen in Endeavour's airlock to cleanse the nitrogen from their bloodstreams in a standard pre-spacewalk procedure. The first task for the spacewalkers was to install thermal sensors on Endeavour's robot arm and at a work site mounted on the starboard wall of the Shuttle's payload bay. The sensors measure temperature levels in the cargo bay to provide data on how hot and cold the spacewalkers can get as they perform their work. Voss and Gernhardt removed a debris shield from the work site, manipulated a duplicate of a computer control box for a robot arm under development for the Space Station and tested new helmet lights and suit heaters as they maneuvered around the cargo bay with relative ease. The spacewalk is scheduled to conclude at about 10 a.m. when the two astronauts climb back into Endeavour's airlock. The remaining three astronauts, Dave Walker, Ken Cockrell and Jim Newman have been assisting with the spacewalk from the flight deck of the orbiter with Newman serving as the primary choreographer with Voss and Gernhardt. Newman performed a spacewalk on a Shuttle flight two years ago to evaluate tools and techniques for future spacewalks.