Disturbing article about the ISS.

[moonmadness]

http://www.msnbc.msn.com/id/22310699/<br /><br />I really hope it's someone being overly dramatic.<br /><br />But this paragraph I found rather ominous.<br /><br />Suffredini said that if both dilemmas persist, the space station may not be able to generate enough power to support the Japanese lab that’s supposed to arrive in three sections beginning in February. There’s “a fighting chance†to keep the first Japanese delivery mission on track, but beyond that, it would be “extremely difficult†to continue assembly, he said.<br /><br /> <div class="Discussion_UserSignature"> <p>I'm not a rocket scientist, but I do play one on the TV in my mind.</p> </div>

 

[erioladastra]

Nope, it is accurate. We are hurting for power even for 1E but can get by. Still checking for 1 J/A. But after that we can't generate enough power to do much more so we have to fix this.

 

[billslugg]

erioladastra<br />We have bit and pieces taken from the bad rotary joint a few months ago. If those pieces were bits and flakes of mylar and duct tape, maybe a bit of copper and mild steel - we have a problem that could be fixed by a lot of effort by Q-tips and compressed air.<br />But, if those bits were tiny chunks of hardened steel, that is bearing races, or bearing rollers, then we have a HUGE problem. We got a piece of grit in there. We lost the clearance. The bearing self destructed. I personally do not believe that the radial loadings and the power inputs were high enough for this to happen.<br /><br />SO - which was it? Harmless pieces of mylar or deadly chunks of bearing race? Any idea? <div class="Discussion_UserSignature"> <p> </p><p> </p> </div>

 

[Testing]

The bits and pieces were proven to be Ferrous last mission. A 12.5' track does not get cleaned by Q-tips, compressed air just blows things to where you can not get to them. This will end up as a tacky rag painting type cleanup. It will not be fun and it will not be fast. SG and I talked about this and I predicted bearing preload. Perhaps it is colder than planned. <div class="Discussion_UserSignature"> </div>

 

[billslugg]

I am not clear yet. <br /><br />On one hand you posit a wet rag type cleanup.<br /><br />On the other hand, you vindicate yourself on a bearing preload cause?<br /><br />Did the bearing fail or did some stuff get in there? <div class="Discussion_UserSignature"> <p> </p><p> </p> </div>

 

[Testing]

A tackyrag is a type of chessecloth treated with an adhesive used in the painting industry. I do not know of a space rated version. Note that they take samples with tape, most likely Kapton with an Acrylic adhesive. I cannot state the materials of the bearings but know of only two space rated bearing materials. 440C, non magnetic, 52100, magnetic. If the preload , radial compression of the roller bearing is too high the surface will Spall, micro crack and flake off. <div class="Discussion_UserSignature"> </div>

 

[holmec]

What is the fix? Replace a solar wing? <div class="Discussion_UserSignature"> <p> </p><p><font color="#0000ff"><em>"SCE to AUX" - John Aaron, curiosity pays off</em></font></p> </div>

 

[comga]

http://collectspace.com/ubb/Forum30/HTML/000633.html has a high resolution of the debris collected on a piece of tape, and includes the statement that this was brought back down on STS-120. It should have been analyzed by now. Anyone heard the nature of that material? Is it 52100 as Testing suggested? (It was described as magnetic by Tani so it shouldn't be 440C.)

 

[earth_bound_misfit]

Sounds like a job for some CRC or WD40, maybe even a smear of space grease <img src="/images/icons/wink.gif" /> <div class="Discussion_UserSignature"> <p> </p><p> </p><p>----------------------------------------------------------------- </p><p>Wanna see this site looking like the old SDC uplink?</p><p>Go here to see how: <strong>SDC Eye saver </strong>  </p> </div>

 

[Testing]

First the true root cause or source has to be found. An alternate track is adjacent to the current one. Then the clean up. Then the replacement of the trundles, or bearings. What I read was one of 12 trundles was removed and brought inside on the EVA today. If it will be examined on orbit or ground I do not know. <div class="Discussion_UserSignature"> </div>

 

[bobw]

Thanks, Comga for the link to the great pictures. I have been looking around but haven't seen any that didn't come off TV. Are those strain gauges on the left, just above the connector on iss16_sarjinspect04-lg.jpg? <br /><br />Edit: <br />This one http://collectspace.com/review/iss16_sarjinspect04-lg.jpg <div class="Discussion_UserSignature"> </div>

 

[Testing]

That is the first good hi res picture I have seen of the damage. Forget about using that race long term. Swap to the backup will be required and pray whatever happened, a surface hardness process or over compress of the bearing trundles is not common. <div class="Discussion_UserSignature"> </div>

 

[earth_bound_misfit]

"We are hurting for power even for 1E but can get by. Still checking for 1 J/A. But after that we can't generate enough power to do much more so we have to fix this"<br /><br />How about hooking a dynamo to the exercise bike? <br /><img src="/images/icons/wink.gif" /> <div class="Discussion_UserSignature"> <p> </p><p> </p><p>----------------------------------------------------------------- </p><p>Wanna see this site looking like the old SDC uplink?</p><p>Go here to see how: <strong>SDC Eye saver </strong>  </p> </div>

 

[docm]

The ability to loft a decent reactor would be better. <div class="Discussion_UserSignature"> </div>

 

[JonClarke]

You have to be kidding. <br /><br />1) No such reactor exists.<br /><br />2) It would have to be very massive as it would need to be sited on a boom 100's of m in length. In addition to the all the otehr systems.<br /><br />3) It would interfer with station instruments,<br /><br />4) It would close off a range of approach angles <br /><br />5 Do you really want a live reactor semi permanantly a few 100 km overhead?<br /><br />Jon <div class="Discussion_UserSignature"> <p><em>Whether we become a multi-planet species with unlimited horizons, or are forever confined to Earth will be decided in the twenty-first century amid the vast plains, rugged canyons and lofty mountains of Mars</em>  Arthur Clarke</p> </div>

 

[bearack]

Probably not viable but, a solar wind mill by chance? Or is there not enough to counter the friction? <div class="Discussion_UserSignature"> <p><br /><img id="06322a8d-f18d-4ab1-8ea7-150275a4cb53" src="http://sitelife.space.com/ver1.0/Content/images/store/6/14/06322a8d-f18d-4ab1-8ea7-150275a4cb53.Large.jpg" alt="blog post photo" /></p> </div>

 

[j05h]

<i>> 1) No such reactor exists. </i><br /><br />What about the SP100 or old Soviet designs? They had both reactors (the infamous radioactive-sodium ones) and a nuclear drive. The designs exist for space-nuclear reactors, there just aren't any being built right now. <br /><br />Your ISS-specific issues (approach, etc) are bigger issues. I'm not sure if it would need such a large boom, though. If two small-ish reactors were built (SP100), they could easily be suspended at the end of the main ISS truss.<br /><br /><i>>5 Do you really want a live reactor semi permanantly a few 100 km overhead? </i><br /><br />Doesn't bother me as long as it's run by responsible parties who don't flush their coolant into space.<br /><br />Josh <div class="Discussion_UserSignature"> <div align="center"><em>We need a first generation of pioneers.</em><br /></div> </div>

 

[vogon13]

ORC DIPS was studied for use on ISS. I think I have an RFP for it around here somewhere.<br /><br /><br /><br /> <div class="Discussion_UserSignature"> <p><font color="#ff0000"><strong>TPTB went to Dallas and all I got was Plucked !!</strong></font></p><p><font color="#339966"><strong>So many people, so few recipes !!</strong></font></p><p><font color="#0000ff"><strong>Let's clean up this stinkhole !!</strong></font> </p> </div>

 

[no_way]

<blockquote><font class="small">In reply to:</font><hr /><p>What about the SP100 or old Soviet designs?<p><hr /></p></p></blockquote><br />I just posted this link in another thread:<br />http://www.world-nuclear.org/info/inf82.html<br />Topaz-I is actually space-qualified and has flown. ESA has considered using it in their probes.<br />US has apparently bought a few Topaz-II designs for "cold" testing. <br /><br />I am not proposing using any of them on ISS, just pointing out that space-qualified reactors indeed do exist.

 

[Testing]

I stand corrected but will quibble that I read 10.5' diameter. Now the question, is that distributed FOD or surface damage on the race itself? <div class="Discussion_UserSignature"> </div>

 

[vulture2]

Replacing the bearing would be a lot easier than designing a new power source. There's a lot more heating and cooling in space than in equipment that's surrounded by air; since only one bearing was affected I'd guess that the installation clearance wasn't sufficient to account for the thermal stresses of a period in sun or shadow. Redesign might be needed. or the spare might not be affected. <br /><br />The big question is whether there will be funds and/or launch capability to make the repairs. In fact, if we are really going to abandon the ISS anyway, why bother even finishing it? When I ask people from Europe or Japan what will happen to the ISS, they throw up their hands and say "Who knows?"

 

[JonClarke]

<i>What about the SP100 or old Soviet designs? They had both reactors (the infamous radioactive-sodium ones) and a nuclear drive. The designs exist for space-nuclear reactors, there just aren't any being built right now. </i><br /><br />As far as I can determine, the SP-100 was never built. if it had, if would have delibered enough power but would have to deployed several km away from the station<br /><br />No Russian reactor has flown in space since 1987 (Kosmos 1867). the reacors were too small small to be useful for a station the size of the ISS (a few kW only). I don't know what the safe distance would be for such a small design, but i would hazard a guess of several 100 m.<br /><br /><i>Doesn't bother me as long as it's run by responsible parties who don't flush their coolant into space.</i><br /><br />No way presently exists for the safe disposal of reactors in LEO.<br /><br />I this this whole discussion is silly. Just because of problem with a bearing people want to go nuclear in space, swapping a technology that is simple, reliable, safe, and high proven for a technology which is none of these.<br /><br />On that notee, let'ssnot highjack this thread further. If people want to discuss how reactors might (or might not) be used o power stations in LEO, start a new thread.<br /><br />Jon<br /><br /><br /><br /> <div class="Discussion_UserSignature"> <p><em>Whether we become a multi-planet species with unlimited horizons, or are forever confined to Earth will be decided in the twenty-first century amid the vast plains, rugged canyons and lofty mountains of Mars</em>  Arthur Clarke</p> </div>