Six-hour spacewalk "superb"

Astronauts test tools for Hubble repairs

Discovery astronauts Carl Walz and Jim Newman conducted a six-hour spacewalk early today, working at a crisp pace as they tested a large power wrench and other hand tools that will be used to repair NASA's crippled Hubble Space Telescope late this year.

The excursion was the third by a NASA space shuttle crew since January, the most for any year since 1985. The accelerated pace should establish a new record for annual spacewalk operations if the Hubble mission is conducted as planned in early December.

"It looks like a beautiful day for a spacewalk," said Walz, a 37-year-old Air Force lieutenant colonel and flight test engineer, as he emerged from Discovery's airlock at 3:40 a.m., Houston time.

Newman, a 36-year-old physicist and adjunct professor at Rice University, followed as the shuttle sailed high above the Pacific Ocean, which reflected a bright blue.

"It's a heck of a view," said Newman. Later, as Discovery soared over Galveston Bay, he gushed, "Houston, you are beautiful."

Though it was the first spacewalk for both men, they seemed quite adept as they maneuvered themselves around the inside of the shuttle's open cargo bay while linked to the ship by long safety tethers. They circled the Earth about four times as they set up a portable work bench, then screwed and unscrewed bolts, opened and closed latches with the electrically powered ratchet. All together they worked with about two dozen hand tools.

"You're doing a superb job," mission control informed the five astronauts. "Keep it up."

Ground controllers rewarded the two men for the aggressive tempo of their work with several minutes of personal sight seeing before they were required to re-enter the airlock.

Walz and Newman toiled in alternating periods of sun light and in darkness with illumination from flood lights. They positioned their feet and hands in a variety of devices to restrain their bodies while they turned tools, lifted and adjusted equipment.

As they worked, Discovery pilot Bill Readdy observed the activities through a window in the shuttle's crew compartment, periodically apprising his colleagues of their progress and providing them with schedule cues.

The entire exercise was documented on video tape so that it can be carefully evaluated by the Hubble's mission planners. Their findings will be factored into the strategy a team of four spacewalkers will employ to replace the bulky solar arrays, a pair of large optical devices, gyroscopes and electronics components on the space telescope.

Hubble managers plan five to seven lengthy spacewalks over 11 days to accomplish each of the tasks necessary to correct the telescope's optical flaws and repair other hardware failures.

In spite of their general adeptness, the difficulties of working in weightlessness were evident at times today as Walz became momentarily entangled in his safety tether, even though the long cord was tensioned so that it would not float completely free in the absence of gravity.

At another point, Walz whirled wildly as he attempted to operate the power wrench without his feet in a restraining device.

"Your body just goes whipping around," Walz observed, emphasizing that there was little point in anyone ever attempting to activate the device while unrestrained.

A stiff power cord on the electric ratchet also proved cumbersome. "This is not how I want to use the power cable," Walz said as he wrestled with the cord. "It's how the power cable wants me to use it."

The spacewalkers provided ground controllers with periodic reports of their exertion levels and whether they were warm enough. Even when their work area was illuminated at times by natural light, the shuttle's cargo bay was never exposed to direct sunlight.

NASA plans to observe the same restriction during the Hubble mission because the sun's rays could damage the telescope's sensitive optics. Warmer gloves and other modifications to the space suits that are being prepared for the Hubble astronauts were not available to Walz and Newman.

However, the colder conditions seemed to have little affect as the astronauts charged ahead of schedule, with little juggling of the scheduled activities.

Also, today Newman examined the hinges and latching mechanisms of the shuttle's cargo bay doors for signs of obstruction from a metal satellite holding device that received minor damage on Sunday when Discovery's crew deployed an experimental communications satellite.

Newman reported no evidence of metal fragments that might impede the closing of the big doors before Discovery descends to a landing next week.