4 p.m. CST, Friday, March 29, 2002
Expedition 4 Crew

Expedition 4 astronauts Carl Walz and Dan Bursch successfully completed an exercise of the International Space Station’s robotic arm today, using six of its joints and a software patch to mask the seventh, the failed wrist roll joint. The exercise consisted of the same activities that the Canadarm2 will use in installation of the S-Zero (S0) Truss on the ISS during Atlantis’ STS-110 mission.

While engineers on the ground will continue to study results of the exercise, it was a major step in proving redundancy in the arm, validating the backup operating string. The prime string was successfully tested on Thursday.

The tests were in preparation for STS-110, to be launched on April 4. The arm will be used to lift the S0 Truss from the shuttle’s payload bay and install it on the station’s U.S. laboratory Destiny. Atlantis crewmembers will do four spacewalks to complete installation.

Today’s test of the arm completed a busy workweek for the crew, Commander Yury Onufrienko, Walz and Bursch. It began with the Sunday arrival of the unpiloted Russian Progress 7 resupply vehicle and concluded with the successful arm operations, completed ahead of schedule. Today’s test was to have been done next Monday.

Science activities continued. Work today involved the ARIS-ICE vibration characterization experiment, the EVA Radiation Monitor and the Advanced Astroculture experiment.

Major systems aboard the ISS continue to function well as the station orbits at an average altitude of about 242 statute miles. Information on the crew’s activities aboard the space station, future launch dates, as well as station sighting opportunities from anywhere on the Earth, is available on the Internet at:

Details on station science operations can be found on an Internet site administered by the Payload Operations Center at NASA's Marshall Space Flight Center in Huntsville, Ala., at:

The next ISS status report will be issued as part of STS-110 status reports, beginning April 4.


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