A computer graphic, created by Boeing, depicts the upcoming installation of the Quest airlock. Image: Boeing

Station astronaut Susan Helms, operating the lab's new Canadarm2 space crane with a jeweler's precision, lifted a 6.5-ton airlock module from the shuttle Atlantis' cargo bay today and attached it to the side of the international space station.

"I think we can call it a total victory," said shuttle pilot Charles Hobaugh. "We did well."

Installation of the 18.5-foot-long airlock, dubbed Quest, completes the second phase of space station assembly and gives on-board crews the ability to stage repair and maintenance spacewalks using U.S. or Russian suits when shuttle crews are not present.

"We're really pleased to have the airlock mated to the station, essentially completing phase two of the assembly of the international space station," said station astronaut James Voss. "Susan did a wonderful job of flying the arm today and getting the airlock on board."

With the addition of the Quest airlock module, the international space station now masses 130 tons, roughly the same as a space shuttle. NASA managers were elated.

"Well, we made history today," said lead flight director Paul Hill. "The international space station reached into the Atlantis' payload bay using its own arm and pulled a cargo element out and installed it," he said. "And voila, the station now has a brand new module. The EVA (spacewalk) started about an hour late, but we made that time up through the course of the EVA and ended 10 minutes early. Atlantis' launch originally was scheduled for mid June, but the flight was put on hold after Helms, Voss and station commander Yuri Usachev ran into a series of subtle problems during tests and checkout of the newly installed Canadarm2 in mid May.

After extensive troubleshooting, the most significant problem, one that intermittently affected operation of the arm's shoulder pitch joint, was traced to a glitch in a diagnostic circuit. Software patches were uplinked to mask out any such false signals and other contingency procedures were developed to handle virtually any arm problem that might develop.

As it turned out, no such emergency procedures were necessary. The arm worked flawlessly and no problems of any significance were reported. Said Hobaugh: "You guys have done a great job today." Gernhardt and Reilly began their excursion, the first of three spacewalks planned during Atlantis' mission, at 11:10 p.m. when they switched their spacesuits to internal battery power. The outing officially ended at 5:09 a.m. for a duration of five hours and 59 minutes.

It was the 106th spacewalk by astronauts on U.S. space missions, the 65th in shuttle program history and the 22nd dedicated to space station assembly. In the 22 station spacewalks to date, 24 astronauts and two Russian cosmonauts logged 145 hours and eight minutes putting the outpost together.

Gernhardt and Reilly spent the initial portion of today's spacewalk installing guide posts and handrails on the airlock that will be needed later. Exactly two hours after the spacewalk began, Helms finally began lifting the airlock module out of its berth in Atlantis' cargo bay. While Gernhardt and Reilly topped off their spacesuit oxygen supplies in Atlantis' airlock, Helms began slowly pitching the airlock end over end and yawing it 90 degrees to line get it into position for attachment to the Unity module's starboard, or right-side, hatch.

Gernhardt and Reilly, meanwhile, floated up to Unity and positioned themselves on either side of the airlock's docking hatch to provide verbal alignment cues to Helms if necessary. They weren't, and Helms smoothly drove the module into position so motorized bolts in the docking mechanism could lock it in place.

"That's a pretty sight, Jim," one of the spacewalkers radioed Voss and the module approached its berth on Unity's side hatch.

"Does it look pretty big?" Voss asked.

"It does, buddy, it really does. It never looked this big in the cradle, I'll tell you." "LIke a big plate in the sky," the other spacewalker chimed in.

"Yeah, I see you guys in the background and you don't look very big compared to it," Voss joked. "Even though you ARE Pillsbury doughboys."

As soon as Quest was in place, Gernhardt plugged in a cable to re-establish "keep-alive" electrical power for the airlock's heaters. The module was launched with its water coolant lines fully loaded and the heaters are necessary to keep them from freezing.

Before returning to Atlantis' airlock, Gernhardt and Reilly installed handrails and foot restraints on Quest's hull that will be needed during spacewalks overnight Tuesday and Thursday to attach four high pressure oxygen and nitrogen tanks. One handrail did not fit properly, but that was of little consequence. "If the only thing that didn't work on this EVA is one little handhold, that's not really that important," Gernhardt said. "We ought to be happy."

Station flight director Mark Kirasich agreed.

"I just wanted to say absolutely fantastic job today," Kirasich radioed Helms from mission control. "It was quite a treat sitting down here watching you."

"Thanks, Mark. Of course I didn't do it alone," Helms replied. "First of all, I had my trusty sidekick Jim (Voss) with me and Yuri (Usachev), of course, was keeping things under control while we were doing this. But we obviouysly didn't do this without thousands of people on the ground helping us and if it hadn't been for you guys and the plan you put together, we never would have gotten where we got today in such a timely way. ... So thanks, Mark. And pass on my thanks to the whole team. We know what you're doing tonight!"

"Yes, well thank you, Susan. It was great to watch. Excellent job."

"Those Canadians really know how to build great hardware, I'll tell you," Helms said of the Canadarm2 space crane.