ISS Crew Restores Oxygen Generator
Almost two weeks of troubleshooting apparently paid off for the
Expedition 9 crew Friday as they restored an onboard oxygen
generating unit to operation.
Work with the Elektron unit, a device that recycles waste water
into oxygen, was one of several maintenance activities completed by
Commander Gennady Padalka and NASA Science Officer Mike Fincke this
With guidance from Russian ground controllers, Padalka had
replaced the Elekron's liquids unit with one he had refurbished
last week using spare components. The Elektron is operating without
a gas analyzer that was removed during troubleshooting. The absence
of the gas analyzer does not affect the Elekron's ability to
generate oxygen, although it may mean the crew will be required to
more closely monitor the unit's operations. Ground controllers
requested the Elektron be turned off before the crew goes to sleep
tonight to allow data gathered during its operations to be
The crew flushed and cleaned several of the Elektron's lines
earlier in the week, as well as cleaning a mounting plate and
removing the gas analyzer.
While the Elektron was off, the Station atmosphere was
repressurized Wednesday using oxygen from the Progress supply craft
docked to the complex. The Station has a supply of oxygen available
in its own tanks, the Progress tanks, and oxygen-generating candles
that could be used for many months if it were needed.
Meanwhile, Fincke replaced a flex
hose that is used to vent an area between panes of the window in
the US Destiny Lab. After depressurizing the window's inner panes,
he replaced the hose and installed a protective cover. The previous
hose had been damaged and allowed air to leak into the area.
The crew has begun some preparations for their trip home next
month. This week, they tested the UHF and VHF communication systems
of the Soyuz spacecraft that will carry them back to Earth. The
communication checks were done with NASA ground stations at the
White Sands Test Facility, the Dryden Flight Research Center and
with the Wallops Flight Facility, allowing NASA sites to be used to
supplement primary Russian ground communications sites.
Fincke also used a camcorder to survey all external US hardware
visible from the Station windows. The video has been downlinked to
the ground for engineers to assess the hardware's condition.
Science activities for the crew included work with the Advanced
Diagnostic Ultrasound in Microgravity experiment. Assisted by
experts on the ground, they conducted body scans with the equipment
to practice the procedures. They also continued providing
information for the Interactions investigation, a computer-based
survey that helps investigators study the interpersonal relations
between crewmembers and ground control teams during long