LIVE: ISS US spacewalk (EVA-20) - November 1, 2012

[dsmillman]

The timeline at:

http://spacestationlive.jsc.nasa.gov/timeline/timelineAstronaut.html?day=Tomorrow&hour=19

is showing Aki performing several EVA prep tasks on Monday October 15.  Do we have a date for the EVA?

EDIT:
http://www.nasaspaceflight.com/2012/10/iss-program-spacewalks-repair-power-channel-faults-station/
- Pete Harding's baseline overview article

Second article - by Pete again:
http://www.nasaspaceflight.com/2012/11/astronaut-duo-spacewalk-iss-isolate-ammonia-leak/

[dsmillman]

On this morning's ISS coverage, the PAO mentioned that the EVA would occur in late October or early November.  Apparently there is a meeting tomorrow (10/16) to make a final decision on the EVA.  The EVA would only deal with the P6 2B ammonia issue.  Also there is a 1.5 hour "Review Spacewalk Procedure" on tomorrow's crew timeline. 

[anik]

http://www.nasa.gov/directorates/heo/reports/iss_reports/2012/10152012.html

"For the upcoming EVA-20, Aki –

Started EVA battery recharge in the A/L BSA (Battery Stowage Assembly),
Configured EVA tethers; [building three safety tether packs using six 85-ft safety tethers (##23/24, 25/26, 27/29) that were inspected as part of the recent EVA Safety Tether inspection activity, and
Initiated METOX (Metal Oxide) cartridge regeneration"

[anik]

http://www.nasa.gov/mission_pages/station/living/index.html

"Williams and Hoshide participated in a conference with flight controllers to review spacewalking procedures for a tentative excursion to repair an ammonia leak in the P6 truss radiator"

http://www.nasa.gov/directorates/heo/reports/iss_reports/2012/10162012.html

"Suni & Aki joined up for a 90-min review of the planned EVA-20, using an uplinked briefing package and new POC DOUG (Portable Onboard Computers Dynamic Onboard Ubiquitous Graphics) software"

[anik]

EVA likely Nov 1

[dsmillman]

From the 10/17 ISS status report:


Akihiko & Sunita conducted jointly a 2 hr procedures review of the upcoming EVA-20 spacewalk. [EVA-20 & EVA-21 are planned between now and the departure of Soyuz 31S on 11/18. The first spacewalk will address issues with the 3A Power Channel. If found necessary, the spacewalk would exchange an SSU (Sequential Shunt Unit) on the starboard truss. Planning for the second EVA is associated with channel 2B and the P6 ammonia leak. The data shows the leak in the loop has accelerated, and that channel could be off-line by the end of the year if the leak trend continues. Channel 2B carries significant loads for the ISS and would have impacts across ISS if it goes down.]

Also for EVA-20, Williams & Hoshide configured required tools, hardware and bags, and reviewed training material on dealing with fluid QDs (Quick Disconnect) hardware carrying toxic ammonia (NH3).

[dsmillman]

NASA TV is catching up with NSF:

November 1, Thursday
7:15 a.m. - ISS Expedition 33 Spacewalk Coverage (Spacewalk scheduled to begin at 8:15 a.m. ET) - JSC (All Channels)

[jacqmans]

MEDIA ADVISORY: M12-205

NASA TO PREVIEW UPCOMING SPACE STATION SPACEWALK TO REPAIR AMMONIA LEAK

HOUSTON -- NASA will hold a news conference at 1 p.m. CDT (2 p.m. EDT)
Friday, Oct. 26, to preview an upcoming spacewalk involving U.S. and
Japanese astronauts aboard the International Space Station. The news
conference will be broadcast live on NASA Television from the
agency's Johnson Space Center in Houston. Media questions will be
taken by telephone and from other participating NASA locations.

Expedition 33 Commander Sunita Williams of NASA and Flight Engineer
Akihiko Hoshide of the Japan Aerospace Exploration Agency will
venture outside the space station Nov. 1 to repair an ammonia leak on
one of the station's port-side radiators. Ammonia is circulated
through the station's external thermal control systems to keep the
electronics and other systems cool.

The Oct. 26 news conference briefers are:

-- Michael Suffredini, International Space Station program manager
-- Mike Lammers, NASA flight director, Johnson Space Center
-- Allison Bolinger, spacewalk officer, Johnson Space Center

To participate by phone, media representatives must call the Johnson
newsroom 15 minutes before the briefing at 281-483-5111. Priority
will be given to journalists participating in person; questions by
phone will be taken as time permits.

NASA Television will provide live coverage of the spacewalk beginning
at 6:15 a.m. CDT Nov. 1. The spacewalk is scheduled to start at 7:15
a.m. and last approximately 6 hours and 30 minutes. This will be the
seventh spacewalk for Williams and the third for Hoshide. It will be
the 166th spacewalk in support of space station assembly and
maintenance.

For NASA TV downlink information, up-to-date schedules and links to
streaming video, visit:

http://www.nasa.gov/ntv

For more information about the International Space Station, visit:

http://www.nasa.gov/station

[anik]

I have talked with Robert Navias today at Baikonur cosmodrome about EVA-20. He said that ammonia leak is from forward radiator. So astronauts during spacewalk should install jumpers for by-passing this radiator and for a connecting aft radiator, which will be deployed. If I have understood him correctly, they will not re-fill PVTCS 2B by ammonia from EATCS in EVA-20. Also Rob has told that the leaked radiator can be replaced in future by spare radiator, for example, from ELC-4.

[psloss]

Thanks for the update, anik.

[Dappa]

I have talked with Robert Navias today at Baikonur cosmodrome about EVA-20. He said that ammonia leak is from forward radiator. So astronauts during spacewalk should install jumpers for by-passing this radiator and for a connecting aft radiator, which will be deployed. If I have understood him correctly, they will not re-fill PVTCS 2B by ammonia from EATCS in EVA-20. Also Rob has told that the leaked radiator can be replaced in future by spare radiator, for example, from ELC-4.

Thanks for the update.

I'm trying to picture how that would work, as far as I know there is only one PVR per PVM. Is there an EETCS radiator (PVR spare) still in place on P6 that will be used for the PVTCS?

[Chris Bergin]

I have talked with Robert Navias today at Baikonur cosmodrome about EVA-20. He said that ammonia leak is from forward radiator. So astronauts during spacewalk should install jumpers for by-passing this radiator and for a connecting aft radiator, which will be deployed. If I have understood him correctly, they will not re-fill PVTCS 2B by ammonia from EATCS in EVA-20. Also Rob has told that the leaked radiator can be replaced in future by spare radiator, for example, from ELC-4.

Very cool! I'd be too busy asking for his autograph!

Pete will have an article previewing this work later today.

[Space Pete]

Thanks for this excellent and timely info anik! Very interesting!

Dappa: Yes, you are thinking along the right lines. You are correct that there is only one PVR per PVM (known as a PVTCS radiator), except that the P6 Truss also contains two extra EEATCS (Early External Active TCS) radiators, one of which will now be extended and effectively "converted" into a PVTCS radiator by installing jumpers to bypass the leaking PVTCS radiator and connect the aft EEATCS radiator in its place.

[Dappa]

So, what is here the aft radiator will be deployed again. 

[Space Pete]

So what is here the aft radiator will be deployed again. 

That is correct, although I don't think we can really call it the aft radiator anymore, since the P6 Truss now rotates along with the SARJ, and so what is aft will change periodically to forward/nadir/zenith.

[dsmillman]

I have talked with Robert Navias today at Baikonur cosmodrome about EVA-20. He said that ammonia leak is from forward radiator. So astronauts during spacewalk should install jumpers for by-passing this radiator and for a connecting aft radiator, which will be deployed. If I have understood him correctly, they will not re-fill PVTCS 2B by ammonia from EATCS in EVA-20. Also Rob has told that the leaked radiator can be replaced in future by spare radiator, for example, from ELC-4.

Do we have a document on L2 that can provide detailed information on the plumbing that supports the P6 radiators?

[Space Pete]

Do we have a document on L2 that can provide detailed information on the plumbing that supports the P6 radiators?

Oh yes, we do. Check the ISS section now.

[Prober]

So what is here the aft radiator will be deployed again. 

That is correct, although I don't think we can really call it the aft radiator anymore, since the P6 Truss now rotates along with the SARJ, and so what is aft will change periodically to forward/nadir/zenith.

So this EVA is a temp bypass of the main system until a new radiator can be installed?

[Space Pete]

So this EVA is a temp bypass of the main system until a new radiator can be installed?

I don't know whether it will be permanent or temporary, and if it is temporary, for how long.

Although a new radiator could be installed, I don't know whether they actually plan to do so.

[Chris Bergin]

Right everyone, get your eyeballs wrapped around this epic article by Pete!

http://www.nasaspaceflight.com/2012/10/iss-program-spacewalks-repair-power-channel-faults-station/