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#21
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Mike Walsh wrote:
To the Russians credit, they actually have a working system up there and if their Elektron fails then they might have to burn one of their oxygen generating "candles" that have worked so well in the past, at least if they didn't cause a major fire. They are using O2 from Progress right now, from what I have read. In terms of the O2 candle fire, as long as it doesn't occur again over a statistically significant period of time , one can conclude that the russians have learned their lesson and have changed procedures/design to help prevent this from occuring again. One negative is that I don't believe we even know whether or not Russia has anyone actually spending the money to have any organization actively trying to improve Elektron. Hard to improve something before you know what actually happens to cause the problem. And that is exactly what the crews are doing right now. And yes, judging from comms, they do have engineers in russia providing support. But again, until they know what exactly goes wrong in 0g, the ground engineers can't really fix anything. It appears to me that rather than accepting the Russian equipment as super-qualified because it has been around for a long time that a combined U.S. Russian program to improve certain specific capabilities (Elektron, space suits, oxygen generating devices) could be very productive. No offense to americans, but they have exactly 0 experience with O2 generators actually running in 0g, unless you count the handfull of US crewmembers who have worked on elektron. So the USA really couldn't contribute much to fixing Elektron problems. The question you should be asking instead is: Have the americans finally made CDRA totally reliable ? Remember that it too has been proiblematic from the start. Lets not forget that Elektron has been running for close to 4 years now. You hear more about its problems because it is more critical than CRDA which is just a backup of the russian CO2 scrubber. In terms of the suits, in terms of the US suits, NASA is having to learn to do in-orbit maintenance due to the shuttle being grounded, so it is understandable that failures are occuring. (They were designed to be brought back to ground for regular maintenance). Since the last EVA was succesful, one can conlude that they were able to succesfully fix the kinks i the russian suits. Hopefully, they have improved the pre-EVA testing and procedures to prevent thsoe kinks from occuring again. They did learn about station attitude relative to russian suit exhausts if the CMGs are offline. All in all, I think that the couple of years without shuttle have been extremely good for the station's programme in general since it has allowed some innovation, and forced NASA to become more pragmatic (for instance, accepting empty station during EVA, accepting that 2 crewmembers can don their spacesuits without needing a 3rd person etc). It has also forced formerly "not field serviceable" parts to be serviced in space. By having unplanned/untrained operations, this proves that "skills based training" as opposed to "specific task training" has far more value and works well. |
#22
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During morning DPC (tuesday), it was said that there was no planned work on
Elektron today (with a comment that things could change). |
#23
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"Mike Walsh" This makes me wonder just how much clout NASA has over the Russian equipment that goes on the ISS. Well uh the Russian folks have let it be known that they will aid the US in support of ISS through 2005, but that if the US is not flying and not willing to contribute to Russian flights, that the Federation will regard that the US is not a particpant, and so Russia will make its own plans for 2006 and after. NASA clout, as you call it, would probably be insignificant. |
#24
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"Greg D. Moore \(Strider\)" wrote in message .. .
If 747s were falling out of the air as often as Elektron fails, we'd still be taking ships across the Atlantic. Aviation started 100 years ago and is used en mass. Space stations are not. Pieces are handcrafted and one of a kind. Less users means less testing. Which means more unsolved bugs. So in other words the purpose of living in space is to find out how to live in space? A bit circular, wouldn't you say? Remember what Tsiolkovsky said: "The Earth is the cradle of the mind, but we cannot live forever in a cradle" Eventually we will have to expand outwards. We should expand outwards anyway in order to not have all our eggs in the same planetary basket. Unfortunately space is currently inhospitable for us and until we learn how to live off the fat of the land, it will not be exploited like it should be. I'd love to see the actual MTBF for Elektron. The perception at least is it isn't all that great for something that's what, 20 year old technology at this piont? Sure, have you got any better alternative lying around? |
#25
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"Derek Lyons" wrote in message ... John Doe wrote: Systems that use liquids in 0g cannot really be tested on earth. They are tested and debugged while in orbit. And as time goes on, they discover new problems that crop up. That is what the space station is REALLY all about. Not research on how to grow crystals, but how to make and maintain/fix systems that are in long term use. Sensible. The problem is, the Russians advertised this as a functional device ready for operational service. Like so much else they have claimed, it's been shown to be a lie. Elektron works better than the US O2 generator. The real problem is that NASA didn't bother to fund US backups to Russian equipment. I'm sure this was partly due to reliance on the shuttle. After all, the US backup plan would likely have been to just keep sending up O2 to put in the US airlock's high pressure tanks. Even if Elektron worked 100% of the time, this still leaves the US with zero real experience with regenerative life support systems in zero gravity. This is a serious failure of the US not fully funding its own life support systems. They'll find the solution to elektron, and this event will contribute to the elektron maintenance manual, MTBF statistics and resupply requirements over the long term. That's nice. However, the Elektron isn't being manufactured any more. And if we had to go to mars today, I'd trust Elektron far more than some newfangled USA (or other country) O2 generator that has not been tested in space yet. There have been enough failures of elektron to have a good idea of how much and what maintenance will be required over a long period. You'd be a fool. Correction... You be a *dead* damm fool. You'd likely be just as dead with US regenerative life support equipment, because none of it has been fully tested and debugged in zero gravity. Look at how little the US CO2 removal system is used. We're certainly not gaining any experience there that would make me feel comfortable enough to put it on a Mars ship. At least the Russians are trying to keep Elektron running. That's far more than the US is doing in the same field. Jeff -- Remove icky phrase from email address to get a valid address. |
#26
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John Doe wrote:
Lets not forget that Elektron has been running for close to 4 years now. You hear more about its problems because it is more critical than CRDA which is just a backup of the russian CO2 scrubber. Utterly false. Elektron has been *in orbit* for four years, not *in operation*. It's spent a goodly part of that time partially or completely inoperable. D. -- Touch-twice life. Eat. Drink. Laugh. |
#27
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"Jeff Findley" wrote:
Elektron works better than the US O2 generator. In the same sense that my buddies $150 beater (which blows smoke, leaks every fluid, runs crappy only when ambient is above 70F and runs not at all below that) works 'better' than the car which proceeded it does currently. (Said car tossed a rod.) You'd likely be just as dead with US regenerative life support equipment, because none of it has been fully tested and debugged in zero gravity. I've never claimed otherwise. My point is, and has long been, that Russian hardware isn't the all-singing all-dancing fully tested, fully proven, completely and utterly dependable system(s) that it's often portrayed as being in these groups and elsewhere. Statement like 'the Elektron is better than the US system' and 'the Elektron has years of operation' conceal and obscure the truth. D. -- Touch-twice life. Eat. Drink. Laugh. |
#28
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"Mike Walsh" wrote:
[...] if their Elektron fails then they might have to burn one of their oxygen generating "candles" that have worked so well in the past, at least if they didn't cause a major fire. AIUI, those "candles" are similar to US oxygen generators, including the one that left a hole in the Everglades that included a bunch of human remains. It looks like The Atlantic Monthly has started to require logins for their archives of William Langewiesche's articles, but http://www.theatlantic.com/issues/98mar/valujet1.htm is still a good reference. Russia has no lock on mistakes with these familiar and well-understood devices, but they do lead in micro-g experience with uncontained flame; one hopes that the lessons learned from that incident are still learned. But the articles (JO's and the AP one) suggest that the Progress and Quest supplies will cover quite a period of the Elektron being down. /dps |
#29
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Derek Lyons wrote:
Utterly false. Elektron has been *in orbit* for four years, not *in operation*. It's spent a goodly part of that time partially or completely inoperable. I wouldn't say that it spent such a great deal of time "inoperable". Problem is that you only hear about it when it has hiccups. But the rest of the time, it does function. I'd say it has require far less maintenance than the US threadmill for instance. Consider this: you have anode and cathode in a glass of water. You apply power. Oxygen bubbles form on one, hydrogen bubbles form on the other. Gravity means that those bubbles eventually detach from the metal part and rise to surface. You want to keep the O2 separate from H2 because you want to send O2 to cabin air, while capturing H2 and vent it to space without venting the water with it. Remove gravity and start to think about how one would capture those tiny O2 bubbles that form, capture those tiny H2 bubbles that form and extract those while leaving the water in there. (oh, and you need to measure water level so that you can continue to add water as needed, and since there is no gravity, you can't use anything the "floats" to tell you about the water level. And consider the implications of having any impurities in the water over a long period of time. (can pure distilled water be electrolysed, or must it contain a few impurities to allow current to flow through it ?) |
#30
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"Derek Lyons" wrote in message ... "Jeff Findley" wrote: Elektron works better than the US O2 generator. In the same sense that my buddies $150 beater (which blows smoke, leaks every fluid, runs crappy only when ambient is above 70F and runs not at all below that) works 'better' than the car which proceeded it does currently. (Said car tossed a rod.) Not at all. To my knowledge, the US has never operated an oxygen generation system in space, at least not one that cracks H2O to get O2 and H2. That's like saying you'd have complete confidence in the US ability to create a nuclear powered aircraft that couldn't possibly crash on the first flight. Remember the "unsinkable" Titanic? It looked great on the drawing board, but sank anyway. You can't say the same thing wouldn't happen to a US O2 generator when it is ran in zero gravity. My point is, and has long been, that Russian hardware isn't the all-singing all-dancing fully tested, fully proven, completely and utterly dependable system(s) that it's often portrayed as being in these groups and elsewhere. Statement like 'the Elektron is better than the US system' and 'the Elektron has years of operation' conceal and obscure the truth. I agree with your point, but you keep asserting that the US could do better on its first try than the Russians have done with a series of Elektron units that have actually been flown in zero gravity. That's a completely baseless assertion. Jeff -- Remove icky phrase from email address to get a valid address. |
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