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Post by antoniocc on Mar 9, 2010 6:56:35 GMT -4
Yesterday I was talking with my father about Apollo, and on the talk it surfaced that he couldn't believe that they didn't make the CO2 filters in the CM and the LM interchangeable. I said to him that it was an oversight, but that left me thinking two things:
1. Was there some reason for that?
2. Has any HB used this as an argument?
Note: my father is not an HB... yet. I fear that if somebody airs the FOX "documentary" here, he will jump into the bandwagon as he has in other conspiracies.
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Post by PhantomWolf on Mar 9, 2010 7:07:19 GMT -4
They were made by different companies. The smaller CO2 filters in the LM and the PLSS were interchangable though. Interestingly the CO2 filters carried in the LM of Apollo 13 would have lasted for all but about 4-6 hours of the trip. They had two of the large filters and three smaller ones in the LM, but they'd have had to run them with near dangerously high levels of CO2.
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Post by Jason Thompson on Mar 9, 2010 8:24:34 GMT -4
Not what you want to be doing at the time when they have to concentrate on powering up the command module and organising cutting loose the service and lunar modules prior to re-entry....
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Post by blackstar on Mar 9, 2010 11:19:56 GMT -4
I don't think any HB has used it because it tends to work against their idea of a super slick conspiracy, I mean no one creating a back story is going to include something so implausible as those incompatible filter cartridges; only the real world throws up such bizarre occurrences.
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Post by Jason Thompson on Mar 9, 2010 11:38:09 GMT -4
I wouldn't be so sure of that. Remember many HBs point to the 'implauibility' of the LM as a spacecraft as evidence of faking it, because obviously a spacecraft should have thick walls, loads of shielding, be pointy and have wings....
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Post by PeterB on Mar 10, 2010 8:18:34 GMT -4
Yesterday I was talking with my father about Apollo, and on the talk it surfaced that he couldn't believe that they didn't make the CO2 filters in the CM and the LM interchangeable. I said to him that it was an oversight, but that left me thinking two things: 1. Was there some reason for that? It wouldn't surprise me if NASA made no conscious attempt to provide for such situations. In "Apollo The Race to the Moon" Murray and Cox point out how NASA Manager of the Apollo Spacecraft Programs Office Joe Shea urged designers to settle on spacecraft designs, regardless of how they might be improved, with the catchphrase, "The better is the enemy of the good." In other words, perhaps in time it might have occurred to designers of the CSM and LM to standardise equipment, but in the meantime, if it did the job it was supposed to, why bother? Don't know - it sounds a bit more technical than most HBs in my experience. It'll now be interesting to see if Dave McGowan leaps onto it. Can you get pre-emptive and just leave some Apollo DVDs or books just, y'know, lyin' around?
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Post by Glom on Mar 10, 2010 9:10:51 GMT -4
It sounds like the kind of thing I was talking about in the other thread. HBers, prejudiced into believing the hoax conspiracy theory, latch onto anything they can use to undermine faith in reality. With that done, they just leap head long into believing the conspiracy theory, regardless of how fat a non sequitur it is.
That anything need not be anything that is even remotely consistent with the conspiracy theory, let alone implicative of it.
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Post by antoniocc on Mar 10, 2010 10:03:37 GMT -4
They were made by different companies. The smaller CO2 filters in the LM and the PLSS were interchangable though. Interestingly the CO2 filters carried in the LM of Apollo 13 would have lasted for all but about 4-6 hours of the trip. They had two of the large filters and three smaller ones in the LM, but they'd have had to run them with near dangerously high levels of CO2. That's what I thought. And thanks for the info. In "Apollo The Race to the Moon" Murray and Cox point out how NASA Manager of the Apollo Spacecraft Programs Office Joe Shea urged designers to settle on spacecraft designs, regardless of how they might be improved, with the catchphrase, "The better is the enemy of the good." In other words, perhaps in time it might have occurred to designers of the CSM and LM to standardise equipment, but in the meantime, if it did the job it was supposed to, why bother? Yeah. When he comes back from work he becomes a classic couch potato (he seems to be addicted to the local copy of Faux News).
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Post by ka9q on Mar 13, 2010 13:11:24 GMT -4
They were made by different companies. The smaller CO2 filters in the LM and the PLSS were interchangable though. Interestingly the CO2 filters carried in the LM of Apollo 13 would have lasted for all but about 4-6 hours of the trip. They had two of the large filters and three smaller ones in the LM, but they'd have had to run them with near dangerously high levels of CO2. Are you counting the LiOH cartridges carried outside the LM cabin inside the MESA? Replacement LiOH and batteries for the PLSSes were carried there because internal storage space was limited and they wouldn't be needed until after the first EVA anyway. I've always wondered if they would have seriously considered an EVA to get those extra LiOH cans if they had not been able to adapt the CM supply to the LM. An EVA would have expended some O2, but that's actually the one consumable they had the most of; battery power and especially cooling water were the real problems. That water was still needed for cooling was ironic considering how cold the cabin got.
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Post by JayUtah on Mar 13, 2010 13:59:11 GMT -4
Replacement LiOH and batteries for the PLSSes were carried there because internal storage space was limited...
Understandable; I just transfered a whole bunch of junk from my glove compartment to the trunk. I really don't need the tire gauge up there. If I need the tire gauge, the car will be stopped and I can get to the trunk.
That water was still needed for cooling was ironic considering how cold the cabin got.
Much of the LM's heat-producing equipment is in the unpressurized aft equipment bay mounted on individual water blocks. They have to be cooled the same way no matter what the cabin temperature.
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Post by drewid on Mar 13, 2010 13:59:54 GMT -4
I consider that to be proof of reality rather than hoax. Companies and departments not talking to each other and comparing specs.
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Post by PhantomWolf on Mar 13, 2010 21:48:55 GMT -4
They were made by different companies. The smaller CO2 filters in the LM and the PLSS were interchangable though. Interestingly the CO2 filters carried in the LM of Apollo 13 would have lasted for all but about 4-6 hours of the trip. They had two of the large filters and three smaller ones in the LM, but they'd have had to run them with near dangerously high levels of CO2. Are you counting the LiOH cartridges carried outside the LM cabin inside the MESA? No, they had 2 canisters in the system initally, 1 large and 1 small. Both PLSS contained a single small canister, and they carryed one spare large one inside the LM. I do have to wonder how they felt knowing that they were just inches from the other spare PLSS and LM canisters, but totally unable to reach them.
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Post by ka9q on Mar 14, 2010 1:03:49 GMT -4
Much of the LM's heat-producing equipment is in the unpressurized aft equipment bay mounted on individual water blocks. They have to be cooled the same way no matter what the cabin temperature. Right. As I recall, after the coolant passes through the sublimator it goes through the ECS (Environmental Control System) to cool the cabin and then it passes through the cold rails in the aft equipment bay and back to the sublimator. This gave the ECS the coldest coolant as the equipment could tolerate warmer temperatures than the astronauts. Too bad there was no way to reverse the direction of coolant flow so that the waste heat from the aft equipment bay could be dumped into the ECS to warm the cabin and the astronauts and reduce cooling water consumption. But this mode would only be useful were the LM to be operated at extremely low power levels for several days, such as in a "lifeboat mode", and the chances of that ever happening as part of a survivable failure scenario were vanishingly remote...
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Post by ka9q on Mar 14, 2010 12:40:39 GMT -4
I took a look at the diagrams for the LM's environmental control system (part of all that documentation that's been supposedly destroyed, of course). The two glycol loops are not the same. The primary loop runs from the primary sublimator first to the batteries in both stages, then the pumps, the suit gas heat exchanger and cabin electronic equipment cold plates in parallel, then the suit liquid loop heat exchanger and then the aft equipment cold plates.
But before returning to the sublimator, the primary glycol loop passes through a regenerative suit heat exchanger. Apparently this is designed to allow heat from the glycol loop to be transferred back to the oxygen fed to the astronauts's suits and/or the cabin, providing some ability to heat the cabin. (The suit gas heat exchanger handles O2 returning from the suits and cabin, so cold coolant is used to condense exhaled water vapor. Just before returning to the sublimator the glycol will be much warmer, so it's optionally used to warm the O2 being fed to the cabin and suit circuits.)
This is very interesting because it would seem to do just what I had wanted to do: dump the waste heat from the aft equipment bay into the cabin. Under the emergency power down situation on Apollo 13, this should have helped keep the astronauts warm while minimizing (or maybe avoiding) the use of cooling water in the sublimators. So I'm wondering why it was necessary to use any cooling water at all when the cabin was so cold; it should have been possible to transfer all the heat from the aft equipment bay to the cabin instead. Any ideas?
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Post by ka9q on Jul 21, 2010 15:10:22 GMT -4
Any thoughts (Jay?) on this cooling/heating issue on Apollo 13? Why couldn't the waste heat from the LM electronics (which are mostly in the aft equipment bay, as Jay points out) have been dumped into the cabin to keep the astronauts warm instead of being dumped overboard by the sublimator, consuming precious water while the astronauts froze?
It looks to me that the LM cooling system should have been able to do this. In normal operation the sublimator would be needed to dump excess heat from the electronics and crew, but in the powered-down mode it should have been possible to shut it down whenever the crew cabin was too cold.
What am I missing?
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