November 7, 2005

Space station crew begins spacewalk late

By Irene Klotz

CAPE CANAVERAL, Florida (Reuters) - The two men aboard the
International Space Station floated outside their orbital
outpost on Monday to prepare the complex for its next phase of

The start of the spacewalk was delayed an hour after the
crew and NASA flight directors realized they did not know if a
critical vent valve was open or shut.

U.S. station commander Bill McArthur and Russian flight
engineer Valery Tokarev were just minutes away from the start
of the spacewalk, scheduled to begin at 9:30 a.m. EST (1430
GMT) when the problem surfaced.

"Valery, do you remember checking the valve,?" McArthur, a
veteran of two previous spacewalks, asked his partner.

Tokarev could not recall, and flight directors then
repressurized the chamber so Tokarev could reopen the hatch and
check the valve.

The valve is needed to remove the last bit of air from the
airlock and also would be used in case of an emergency
repressurization, said NASA spokeswoman Kylie Clem.

Finding the vent closed, Tokarev switched it open then
checked the position of another valve before backing out
through the hatch and sealing the door shut again.

The men checked the chamber for leaks, gathered their
tethers and finally were cleared to open the outer hatch.

"It's beautiful," McArthur said, sneaking a peek out the
door as he and Tokarev switched their suits to battery power
and prepared to begin the planned 5 1/2-hour spacewalk.

Their first job was to install a television camera at the
end of one of the station's truss segments. The camera is
needed to guide a future space shuttle crew that will be
attaching a new truss segment and solar array panels.

Next, McArthur and Tokarev planned to remove a sensor that
had been monitoring the electrical fields that build up around
the station as it blasts around the planet at 17,500 mph
(28,000 kph). Engineers believe components coming off the probe
present a debris hazard and want the device removed to prevent
any damage.

The spacewalk by space station crewmembers was the first in
2 1/2 years from the U.S. airlock and under NASA's direction.
The airlock and a pair of U.S. spacesuits were contaminated by
rust and other materials from a corroded device in the
airlock's cooling system.

The grounding of the space shuttle fleet after the 2003
Columbia accident delayed airlock repairs and the arrival of
fresh spacesuits. In the interim, station crewmembers used the
Russian airlock and spacesuits and were directed by Russian
flight controllers.

NASA still needs to complete a second test flight of the
space shuttle before resuming space station assembly next year.

A second round of repairs to the shuttle's external fuel
tank is under way and NASA hopes to return the fleet to flight
in May 2006. Problems with the tank, which shed debris that
triggered the loss of Columbia and its crew, reappeared during
the July launch of Discovery on the only shuttle mission NASA
has flown since the accident.