International Space Station Status Report #51 - 2004

Allard Beutel
Headquarters, Washington September 10, 2004
(Phone: 202/358-4769)

INTERNATIONAL SPACE STATION STATUS REPORT: SS04-030

Russian engineers will spend this weekend analyzing an
intermittent problem with the International Space Station
(ISS) primary oxygen-generating device. Although the crew is
in no danger, engineers want to better understand the
situation before taking corrective action.

The oxygen-producing Elektron was restarted today after
Expedition 9 Commander Gennady Padalka performed
troubleshooting work. It shut down again after operating for
approximately one hour. Russian specialists decided to forego
additional troubleshooting until Monday. They will have more
time to determine why a gas analysis mechanism in the system
commanded the Elektron, which is located in the Station's
Zvezda Service Module, to shut down two other times after
Padalka cleaned and flushed lines in the device. The Elektron
originally shut down on Wednesday, prompting Padalka's
maintenance work.

Despite the intermittent performance of the Elektron, there
is plenty of oxygen in the Station's cabin atmosphere. U.S.
flight controllers slightly increased nitrogen levels on
board with nitrogen from the Quest airlock tanks. No
additional repressurization of the cabin atmosphere is
required. The Elektron's temporary shutdown poses no
immediate impact on ISS operations.

After several hours of work on the system this morning,
Padalka told Russian flight controllers, the reassembled
Elektron had twice run for about five minutes before shutting
down. Eventually, Padalka and flight controllers disabled an
Elektron gas analyzer sensor system, and the device continued
to operate for a little more than an hour before it commanded
itself to shut off again. The Elecktron separates water into
oxygen for ISS use and hydrogen, which is vented overboard.

Russian flight controllers believe a modification in the
software that regulates commands for the gas analyzer could
fix the problem early next week.

Padalka and NASA Flight Engineer/Station Science Officer Mike
Fincke completed their 145th day in space today and their 143rd
day onboard the orbiting laboratory.

On Wednesday, Padalka used spare parts sent up on a Russian
Progress resupply spacecraft last May to bring a spare
liquids unit for the Elektron back to operational status.
There are no plans to use the backup unit, but it is
available, if needed. The Progress docked to the ISS has full
oxygen and air tanks. Additional oxygen is available in two
high-pressure tanks on Quest, if they are needed. There are
84 Solid Fuel Oxygen Generator canisters, a 42-day supply of
oxygen for the crew, available, but there are no plans to use
any reserve oxygen supplies.

Earlier in the week, Padalka and Fincke conducted routine
housekeeping tasks and a few post-spacewalk tasks, including
the stowage of spacewalking tools and the servicing of the
Russian Orlan space suits.

Fincke also conducted optional science activities, including
some remaining data takes with a Dutch experiment that helps
to characterize the performance of a grooved heat pipe in
microgravity. European Space Agency astronaut Andre Kuipers
brought up the experiment to the Station in April.

Both crewmembers worked with other science and medical
experiments this week. Padalka conducted the PLANTS
experiment as well as the PROFILAKTIKA experiment. It is
designed to study countermeasures to negative physiological
effects of lengthy spaceflight.

Fincke also performed proficiency training for the Advanced
Diagnostic Ultrasound in Microgravity medical experiment and
on Thursday, both crewmembers participated in a bone scanning
procedure. That research will not only assist with onboard
medical situations but is being developed for possible use in
remote areas on Earth.

Padalka and Fincke wrapped up their week with a televised
conversation with Native American students at the United
Tribes Technical College in Bismarck, N.D. It was the
featured event during the 35th Annual United Tribes
International Powwow. NASA representatives from the Johnson
Space Center and the Langley Research Center attended the
powwow and tribal meetings to promote NASA education and
Explorer Schools.

Information about crew activities on the ISS, future launch
dates and Station sighting opportunities from Earth, is
available on the Internet at:

http://spaceflight.nasa.gov/

For details about Station science operations on an Internet
site administered by the Payload Operations Center at NASA's
Marshall Space Flight Center, Huntsville, Ala., visit:

http://scipoc.msfc.nasa.gov/


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Jacques :-)

www.spacepatches.info