Space Station AC Still on the Fritz After 8-Hour Spacewalk

By Joseph Calamia | August 9, 2010 11:11 am

spacewalkUsually, a hitch encountered while fixing an air conditioner doesn’t make the news–except when that AC orbits 220 miles above the earth, requires astronaut mechanics, and remains inoperable after the sixth longest spacewalk in history.

Last week, we discussed a broken ammonia cooling loop–one of two keeping the International Space Station air-conditioned and habitable. Though the second loop is keeping the six astronauts aboard comfortable, they prefer to be more than mishap away from a 500 degree Fahrenheit temperature difference across their orbiting laboratory. Now, following Saturday’s eight-hour spacewalk, the cooling loop is closer to repair but will require two additional walks. The next will occur no earlier than Wednesday, a NASA press release says.

NASA had announced previously that the repair would take multiple walks. The astronauts originally planned to remove four coolant lines on Saturday, a necessary step before removing and replacing a broken pump. This spacewalk ran into trouble with the second line’s fitting–which jammed. Said Michael T. Suffredini at the Johnson Space Center in Houston:

“Ammonia QDs are known to be sensitive systems,” he said referring to the quick-disconnect fittings. “They’re very complicated; it’s very high-pressure ammonia you have to try to be able to disconnect and reconnect on a regular basis…. We will get through this problem,” he said. “The challenge is to get through this problem before the next problem hits the other cooling system.” [The New York Times]

The pair of astronauts on the walk, Doug Wheelock and Tracy Caldwell Dyson, moved on to the remaining lines which they successfully removed before doubling back to the second. They successfully removed the line but noticed ammonia ice crystals–a leak. Mission Control in Houston instructed the astronauts not to attach the line to a “bypass mechanism,” so they reattached it to the fitting before ending the walk to plan for the next attempt.

Because of the leak, the spacewalkers spent extra time in the airlock to flush out any ammonia that may have attached to their spacesuits. The decontamination procedure is routine whenever spacewalkers are exposed to free-flying ammonia, which can be a hazard if it gets into the space station’s air. [ABC News]

Related content:
80beats: ISS Astronauts Plan Emergency Spacewalk to Fix the Station’s A.C.
80beats: Shuttle Astronauts Add the ISS’s Last Major Piece
80beats: “Interplanetary Internet” Will Soon Bring Twitter to the ISS
80beats: Strife on the Space Station: Russians Can’t Use American Toilet
80beats: Space Junk, Spacewalks, and Pee Trouble: News From the ISS

Image: NASA TV

CATEGORIZED UNDER: Space
  • http://Untitledvanityproject.blogspot.com Rhacodactylus

    It’s so easy to think of space travel as almost “routine” these days, I know I’m guilty of it. But, it must take insane nerves to have your life hanging on “loop 2″ of the AC unit. Astronauts are bad-asses of the Nth degree.

    ~Rhaco

  • Brian Too

    If the cooling loops are so critical, shouldn’t they be triple redundant?

    Or is this in the category of, well the astronauts might be uncomfortable, but the station would in fact be livable? After all the station is filled with air and that could buffer the temperature swings a lot.

    If worse came to worst I suppose the astronauts could suit up. I don’t believe that anyone would recommend living that way for long though.

NEW ON DISCOVER
OPEN
CITIZEN SCIENCE
ADVERTISEMENT

Discover's Newsletter

Sign up to get the latest science news delivered weekly right to your inbox!

80beats

80beats is DISCOVER's news aggregator, weaving together the choicest tidbits from the best articles covering the day's most compelling topics.
ADVERTISEMENT

See More

ADVERTISEMENT
Collapse bottom bar
+

Login to your Account

X
E-mail address:
Password:
Remember me
Forgot your password?
No problem. Click here to have it e-mailed to you.

Not Registered Yet?

Register now for FREE. Registration only takes a few minutes to complete. Register now »