Rail-riding ISS Cart Jams (Spacewalk Monday AM)

[WuphonsReach]

http://www.planetary.org/blogs/jason-davis/2015/20151218-mt-jams-contingency-spacewalk.html?referrer=https://www.google.com/

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A rail-riding cart weighing nearly a metric ton jammed while moving along the International Space Station's exterior yesterday, prompting ground controllers in Houston to prepare for an unscheduled spacewalk.

 

Edited December 21, 2015 by WuphonsReach
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[Findthepin1]

I didn't know it had a rail. When was that put up?

[sgt_flyer]

there's a lot of things riding on those rails, the canadarm itself is mounted on that rail (not at first, it was in a fixed position before the main trusses were added, afterwards it was mounted onto it) the rail itself is integrated within the long trusses connecting the habitat section to the solar panels / radiators - so the rail was added to ISS when those trusses were added

now, basically, they use the rail to move heavy spaceworthy equipment (experiments, modules, the canadarm, etc) alongside the spine of the station. makes life much easier during spacewalks, as even if there's microgravity, you still have inertia to contend with  (and a 1 metric ton thing you'll have difficulties stopping that thing without assistance ;))

Edited December 19, 2015 by sgt_flyer

[Shpaget]

Space train refusing to chooch?

[WuphonsReach]

They've been replaying the 5 minute interview with the ISS boss-guy most of the day on NASA TV UStream.  Still no word on when they'll do the EVA to fix the issue, but they might decide Sunday.

http://www.csmonitor.com/Science/2015/1219/Why-an-emergency-spacewalk-is-needed-on-ISS

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Flight controllers in Houston were moving the rail car on the outside of the orbiting lab when it got stuck Wednesday. It stalled just 4 inches from its lock-down position.

NASA operations manager Kenny Todd said Friday the car needs to be securely attached to its guide rails before any dockings by visiting spacecraft. Russia plans to launch a supply ship Monday for a linkup Wednesday.

 

https://blogs.nasa.gov/stationreport/2015/12/17/iss-daily-summary-report-121715/

There's quite a bit docked up at the ISS right now:

• Progress 60 departed this morning (making room for #62)
• Soyuz 44 and Soyuz 45
• Progress 61
• Cygnus-4

https://blogs.nasa.gov/spacestation/2015/12/19/russian-cargo-spaceship-departs-station/

[sgt_flyer]

makes sense, visiting spacecrafts (except for progress / soyuz and ATV automatic approaches) are manipulated with the canadarm for berthing operations. so if you can't move the canadarm as you wish because something's in the way, you want to clear up the problem's ASAP (though, they will still take the time to prepare the astronauts for the spacewalk - like rereading technical data they have on the stuck car, and checking with the engineers responsible of it to set the best course of action  (and maybe data gathering on the problem, using any camera they an point at the thing) 

heck, they might even plan to simply have a look to the problem, ,and attach the thing so they are sure it won't move in preparation for ulterior repairs. (who knows, they might even add the spare parts to progress's payload if really needed ;))

Edited December 20, 2015 by sgt_flyer

[WuphonsReach]

Depends on what the close-out time is for a Progress launch.  I know the Cygnus launch, they were talking about a two-week long button-up period, which limited types of what they could bring up in the last launch due to riding on the Atlas.

[Wjolcz]

I actually didn't know they had a rollercoaster mounted up there.

 

So when is the EVA happening?

[WuphonsReach]

http://www.floridatoday.com/story/tech/science/space/2015/12/20/nasa-astronauts-go-monday-spacewalk-outside-iss/77672852/

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Scott Kelly, the Expedition 46 commander, and Tim Kopra, who just arrived at the station last week, are expected to begin a minimum three-hour spacewalk around 8:10 a.m.

There's also a Progress launch  -- 3:44 a.m. EST on Monday

[Glaran K'erman]

CETA cart work went well, got motion real quick and cart was moved successfully to the center of it's targeted workstation. Now going to work on some "get ahead" tasks. Fun!

 

EDIT: It's over and everything went smoothly. Looking forward to the next EVA on Jan 15/16!

Edited December 21, 2015 by Glaran K'erman

[Mitchz95]

Progress, an EVA and the SpaceX return-to-flight ... busy day.

[WuphonsReach]

It was fairly interesting to watch as they had video first-person view from the astronaut's helmets as well as some wide-shots from various cameras around the ISS.