Shuttle Atlantis on its Way to Space Station Alpha ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ By Todd Halvorson Cape Canaveral Bureau Chief posted: 05:13 am ET 12 July 2001 Crew Faces Time-Critical Construction Job CAPE CANAVERAL, Fla. -- Shuttle Atlantis and an all-American astronaut crew blasted off from Kennedy Space Center Thursday, setting out on what will amount to a high-stakes game of "Beat The Clock" at the International Space Station. With a $164 million airlock riding in the shuttle's cargo bay, the quintet of Atlantis astronauts raced toward a Friday night rendezvous at the 17-story complex. And if the orbital portal can't be hooked up to station electricity during a spacewalk Saturday, frigid temperatures could cause internal water lines to freeze up and burst, damaging the airlock and dealing a severe blow to the $60 billion station construction project. That, said Atlantis spacewalker Michael Gernhardt, "would not be a good thing." Yet the shuttle astronauts say they're prepared for that worst-case scenario -- and any others -- that could crop up as NASA and its international partners resume outpost construction some 240 miles (384 kilometers) above Earth. "We've planned this so well, and choreographed this so well, that we don't think that's going to be a problem," Gernhardt said. "We've got it down, and we've got all the cases covered." NASA's 105th shuttle flight got off to an earth-shaking start at 5:03:59 a.m. EDT (0903:59 GMT) as Atlantis thundered off an oceanside launch pad and then arced out over the Atlantic Ocean, blazing a fiery trail through predawn skies. A forecast calling for a chance of stormy weather at NASA's coastal Florida spaceport never materialized, and ground crews executed a problem-free launch countdown before sending the shuttle and its crew aloft. "Looks like the vehicle and the weather and have come together," NASA launch director Mike Leinbach told the astronauts minutes before the shuttle set sail for the outpost. "Good luck and have a great flight." Now circling the planet at 25 times the speed of sound, Atlantis and its four-man, one-woman crew will spend the next two days chasing down the station. The $2 billion spaceship is scheduled to dock at the outpost just before 11 p.m. EDT Friday (0300 GMT Saturday). Anxiously awaiting the shuttle's arrival: Outpost commander Yuri Usachev, a veteran Russian cosmonaut, and his two American colleagues: flight engineers Susan Helms and Jim Voss. In space since March, the outpost crew plans to use the station's new $600 million Canadian robot arm to pluck the 6.5-ton airlock from the shuttle's cargo bay and then swing it up to the starboard side of the U.S. Unity Module. Spacewalkers Gernhardt and Jim Reilly will help mount the airlock to a Unity berthing port before connecting it to station power cables. The spacewalkers and the station crew, however, will face a couple of potential problems during the airlock installation job, which is set to begin just after 10 p.m. EDT Saturday (0200 GMT Sunday). Weekend plans ~~~~~~~~~~~~~ First, the 57.7-foot (17.5-meter) station robot arm -- which is anchored to the outside of the U.S. Destiny laboratory -- must be working properly to carry out the work. That's because the shuttle's 50-foot (15-meter) robot arm is too short to reach the Unity berthing port. The station arm, however, suffered start-up problems during testing in late May and June, raising fears that a failure could leave the airlock stranded at the end of the crane before it can be mounted to the outpost. The troubles with the arm since have been ironed out. But the spacewalkers nevertheless have trained to manually drive its wrist, elbow and shoulder joints so that the airlock can be raised up to the Unity berthing port if the crane for some reason fails. And both Gernhardt and Reilly are confident that job can be done if need be. "As it turns out, it looks to be a relatively easy task to do," Reilly said. "It's just one of those that's going to be very, very time-consuming." Time, however, will be a precious commodity during the planned seven-hour airlock installation job. Cradled in the Atlantis cargo bay, the airlock and its various subsystems are kept at the proper operating temperatures by shuttle heater cables. Those cables, however, will be disconnected at the beginning of the installation job, starting a 10-hour "thermal clock." Practically speaking, that means the airlock must be raised up to the berthing port and connected to station power cables by the end of Saturday's spacewalking sortie. Otherwise, its internal water lines could freeze up - a situation the crew will go to great lengths to avoid. "The objective is not to freeze the water in the lines on the airlock," said Atlantis mission specialist Janet Kavandi. "So that is one of the very first things that we'll have to do once it's docked" to the Unity berthing port. Hooking up the station power cables, in fact, is so important that it would become the highest priority if the installation job runs behind schedule -- or if the astronauts for some reason cannot mount the airlock to the Unity berthing port. In that case, the main objective would be to bring the airlock within three feet (one meter) of the berthing port so that the station power cables can be connected to it. Theoretically, the airlock then could be left hanging at the end of the arm until the ground controllers could figure out a way to finish the installation job -- even if that meant leaving the work to a subsequent shuttle crew. Despite its size, the airlock -- which stretches 20 feet (six meters) from end to end -- would not block an Atlantis departure or a shuttle docking at a later date. So there would be no attempt, under those circumstances, to return the airlock to Earth. Said Atlantis commander Steve Lindsey: "We would leave it on the Canadian arm." With the recent robot arm troubles under control, though, none of the astronauts expect to encounter any of those "what-if" scenarios. And assuming all goes well with the airlock installation, Gernhardt and Reilly will carry out two additional spacewalks during the planned 11-day mission. Slated for next Tuesday and Thursday, the excursions will involve mounting four large oxygen and nitrogen tanks - each of which weigh 1,200 pounds (540 kilograms) -- on the outside of the airlock. About the size of large doghouses, the tanks will enable station crews to replenish air supplies within the airlock. The weeklong flurry of work is to be capped with a July 20 farewell ceremony and then the shuttle's departure from the station the following day. Atlantis and its crew are scheduled to land here about 1 a.m. EDT (0500 GMT) July 23.