First-ever bilaterally-controlled spacewalk scheduled for June
The Expedition 9 crew aboard the International Space Station
spent the week unpacking a Russian resupply ship and getting ready
for a June spacewalk to replace a faulty circuit breaker.
Gennady Padalka, the Station commander, and Mike Fincke, the
NASA science officer and flight engineer, spent several days
unloading about 2 � tons of food, water, spare parts and
supplies from the Progress 14 vehicle that docked to the aft end of
the Zvezda Service Module at 8:55 a.m. CDT May 27.
Flight controllers later will transfer fuel from the Progress'
tanks to those in the Russian modules of the Station.
Preparations for the upcoming spacewalk began in earnest
Thursday, when the orbiting duo began configuring the Russian
spacesuits they will use for the excursion, and charging batteries
that will be used in their suits and cordless tools.
The spacewalk is scheduled for no earlier than June 15 Houston
time. The status of preparations and planning for the spacewalk
will be the subject of further review during regular Station
management meetings next week. The goal is to replace a power
controller that failed April 21, resulting in the temporary loss of
one of three operational Control Moment Gyros (CMGs) that govern
the orientation of the complex.
Although the two functioning CMGs are sufficient to control the
Station's attitude without the use of Russian chemical thrusters,
Station managers and flight controllers would like to have the
additional backup CMG available for attitude control during the
expedition's two scheduled spacewalks later this summer. A fourth
CMG failed two years ago and is slated to be replaced when Space
Shuttles resume flights next year.
This will be the first bilaterally coordinated spacewalk in
history, with flight controllers in Houston and Moscow taking turns
as the primary ground support team.
Russian ground experts will coordinate as Padalka and Fincke don
their Russian Orlan spacesuits, exit the Pirs airlock and use the
Strela cargo crane to travel to the U.S.-built section of the
Station. Once there, American flight controllers will assume
primary responsibility for the replacement of the faulty Remote
Power Control Module (RPCM) and assist with routing power through
the new RPCM to the gyroscope. After power is restored to the CMG,
Houston controllers will assist the spacewalkers in their
hand-over-hand return to the Russian crane and pass responsibility
back to the Russian ground team.
Last week, Fincke and Padalka took turns moving the Station's
Canadarm2 robotic arm to a position along the S0 Truss for camera
views of the spacewalk worksite. Late next week, they are slated to
climb into their spacesuits for a dress rehearsal of the suit up
and systems checkout that will clear the way for the spacewalk.
Padalka and Fincke also conducted Russian hand movement studies
as part of a series of biomedical experiments and routine
housekeeping tasks that filled up the remainder of their