STS-104, Mission Control Center Status Report # 11 Tuesday, July 17, 2001 – 7 a.m. CDT
Shuttle and station crews set aside work on a leaky ventilation valve and pressed forward with activation of
the new Quest airlock and a dry run of the steps they’ll use for the first space walk using the new station
doorway to space.
The practice run included a successful lowering of the airlock’s pressure to 10.2 pounds per square inch for
the first time in space.
Lead Flight Director Paul Hill said troubleshooting on the valve — and work the day before to get air bubbles
out of an airlock water cooling line — have put the combined crew about half a day behind its timeline.
Among the tasks delayed was a relocation of the hatch from the junction of the airlock and the Unity module
to its final position between the airlock’s crew and equipment lock sections.
The second space walk of the flight remains on schedule for Tuesday night. Mission Specialists Mike
Gernhardt and Jim Reilly are scheduled to step out of the space shuttle’s airlock about 9:30 p.m. The
objective of the 5 ? hour foray is to mount one high-pressure oxygen and one high-pressure nitrogen tank
on the shell of the new airlock to provide consumables that would allow expeditioners to leave the station in
American space suits for construction and maintenance work without a shuttle present. Russian space suits
can be used from the airlock as well.
The crews closed the hatches between the two spacecraft at 6:30 a.m. Tuesday to begin lowering Atlantis’
cabin pressure to that same 10.2 pounds per square inch mark. This measure helps purge nitrogen bubbles
from the space walkers’ bloodstreams, and is augmented by the space walkers pre-breathing pure oxygen.
All crewmembers reviewed the procedures for the space walk prior to closing the hatch between the shuttle
and the station’s Destiny Laboratory.
Mission Specialist Janet Kavandi and Expedition Two Flight Engineer Jim Voss took the lead in
troubleshooting the suspected leak in an Intermodule Ventilation (IMV) assembly. The series of fans and
valves circulates air between station modules and connects the airlock to the station’s environmental control
and life support system. The pair wasn’t able to pinpoint the problem with the valve, but did install a cap that
stopped the leak. Should replacement be necessary, several valve replacement options are available to the
flight control team and crew onboard.
The delays have led flight managers to study the possibility for an extra day of docked operations and a
shuttle mission extension to ensure all of the mission’s work can be completed.
Shuttle Commander Steve Lindsey, Atlantis’ Pilot Charlie Hobaugh and Station Commander Yury Usachev
took time late Monday night to answer questions from reporters from CBS, Space.com and KNBC-TV of Los
Angeles.
The eight people on orbit are scheduled to go to bed about 8 a.m. and awaken at 4:04 p.m. The next
mission status report will be issued about 6 p.m. Tuesday or as events warrant.
