ISS Status Report #01-17 – 6 June 2001

The Expedition Two crew this week busily prepared for the first
station-based spacewalk planned for Friday and continues to assist the
ground with troubleshooting of the complex’s robotic arm in the backup mode.

Commander Yury Usachev and Flight Engineer Jim Voss will open hatches in the
Zvezda module beginning Friday morning about 9:30 to reposition a docking
mechanism in preparation for the arrival of a Russian docking module later
this year. They climbed into their Russian spacesuits Tuesday, entered the
transfer compartment and conducted a practice session for the task, which is
budgeted to take about 30 to 40 minutes.

As a precaution, hatches will be closed at various locations on the station
so that the small, ball-shaped transfer compartment can be depressurized.
Flight Engineer Susan Helms will remain in the Zarya module throughout the
Extravehicular Activity (EVA).

Meanwhile, the Canadian Space Agency today planned to send computer commands
to the station’s robot arm, called Canadarm2, to attempt to pinpoint the
cause of a problem with one of its seven joints in the redundant, or backup
mode. Though the primary system of the arm works perfectly, the arm must
have a prime and backup operating system functioning prior to the launch of
Atlantis delivering the Joint Airlock to the complex.

The Canadarm2 is required for the grapple of the airlock in Atlantis’ cargo
bay and its installation on a docking port of the Unity module. The
25,000-pound airlock will allow future station-based spacewalks to be
conducted in U.S. and/or Russian spacesuits. The Shuttle robot arm cannot
reach the Airlock installation location.

In parallel, a software patch is being developed that actually can mask, or
inhibit, the use of the suspect shoulder pitch joint allowing operation of
the arm in six of the seven degrees of freedom. Again, the arm works fine on
its primary string and, in fact, yesterday was maneuvered to what likely
will serve as its stowed, or cradled position, with each end firmly attached
to a grappling pin on the outside of the Destiny laboratory and one on the
tunnel adapter leading to Unity.

Until the Canadarm2 evaluation is completed at week’s end, shuttle and
station managers will not firmly decide on the launch dates for the next two
assembly missions. However, at present the next flight is tentatively slated
for launch in early July pending resolution of the shoulder pitch joint
problem and the conduct of a “dry-run” of the airlock installation. The
follow-on flight remains scheduled for early August carrying a replacement
crew for Expedition Two.

The Expedition Three crew of Commander Frank Culbertson and Flight Engineers
Vladimir Dezhurov and Mikhail Turin today completed training at Star City
outside Moscow.

Science investigations continue onboard under the guidance of the Payload
Operations Center at NASA’s Marshall Space Flight Center in Huntsville, AL,
except for the Human Research Facility, which is monitored and controlled
from the Telescience Support Center (TSC) at the Johnson Space Center,
Houston. For details on ISS science, visit the following website:
http://www.scipoc.msfc.nasa.gov

A status briefing on Expedition Two activities will be broadcast on NASA
Television Thursday, June 7 at 1 p.m. Central time. The briefing will focus
on Friday’s spacewalk and ongoing efforts to ready the station for the
arrival of the airlock on STS-104.

The International Space Station is orbiting at an altitude of around 240
miles (385 km). The next ISS Status Report will be issued Friday, June 8, or
as mission events warrant.