Space station’s new observation deck going for ride on robot arm; Stuck bolts pose problem

Stuck bolts hinder space station deck maneuver

CAPE CANAVERAL, Fla. — Astronauts ran into trouble trying to move the International Space Station’s fancy new observation deck late Sunday, and the job was put on hold as Mission Control debated what to do.

Space station commander Jeffrey Williams was loosening a series of bolts to release the domed lookout from the newly installed Tranquility room when one of them jammed. He backed out of the procedure and tried again. Then, another bolt jammed.

Mission Control informed the station and shuttle crews that engineers were reviewing what happened. In the meantime, the astronauts were instructed to loosen the robot arm’s grip on the observation deck. The arm had grappled the lookout a little earlier in the evening, in order to move the lookout from one side of Tranquility to the other.

As the astronauts were complying, yet another bolt jammed. “Houston sees that,” Mission Control radioed.

Mission Control sent up commands to adjust the torque on the bolts. Williams, in turn, relayed the commands and waited to see if it might resolve the problem.

The $27 million lookout was launched last week in a temporary position on Tranquility that allowed it to fit in Endeavour’s payload bay.

A clearance problem almost scuttled the relocation effort.

On Saturday, a different set of bolts prevented the astronauts from attaching a thermal cover between Tranquility and the observation deck. Williams removed the bolts and managed to secure the hatch cover over Tranquility’s docking mechanisms early Sunday.

After hours of review, NASA concluded there would be no clearance problem when it came time to install the observation deck in its final position.

The lookout — described as a bay window — is 5 feet tall and nearly 10 feet in diameter at its base. It sports seven windows, including the biggest one ever in space.

Because the port was going to be empty once the observation deck was moved, NASA wanted a cover there to keep Tranquility’s docking mechanisms from getting too cold. That port wasn’t going to be vacated for long. The astronauts planned to move a docking adaptor into that slot Monday night.

During the third and final spacewalk of the mission Tuesday night, astronauts are supposed to unlock the window shutters on the observation deck. Then their colleagues inside would crank open the shutters and soak in the views of Earth, outer space and the space station itself. NASA sees the dome as a huge improvement to the quality of life 220 miles up.

The first two spacewalks focused on the installation of Tranquility, a 23-foot chamber that was powered up early Sunday.

Both the dome and Tranquility are European contributions to the space station and represent the last of the major building blocks. NASA’s part of space station construction will end with the retirement of the space shuttle fleet, scheduled for this fall.

Endeavour and its crew of six have been at the orbiting outpost for nearly a week. They will depart Friday.

On the Net:

NASA: www.nasa.gov/mission_pages/shuttle/main/index.html