T O P I C R E V I E W |
DougS | I had a question about Apollo 13 and the lithium hydroxide canister situation they had. As I understand it (and please set me straight if I'm wrong), the lunar module had two round canisters for two men for 30 hours. Then NASA MacGyvered the brilliant solution that they did. Did the crew also take the round canisters out of the lunar spacesuits to give themselves some extra time until the solution was hit upon? Or wouldn't those have fit the lunar module's system? |
Rick | By 2:30 a.m. the night of the accident, a mockup of the contraption that Ed Smylie's group put together was being shown to Ken Mattingly in the mission control center. Testing was done and a few tweaks here and there were made, and then two were actually constructed by the crew on Wednesday morning. I don't think the situation ever got to the point where the crew had to dig into the spacesuits for a temporary fix. |
Andy L | Whilst on this subject, did NASA change the lithium hydroxide canisters on the rest of the Apollo missions so that they were the same in both the CM and the LM? |
SpaceAholic | Nope... would have required a significant redesign of the ECU to account for different cartridge geometries, flow path, stowage and disparate demand rates from each system. |
DougS | Thanks for the info, Rick! |
moorouge | There's a step by step guide to making your own converter here. |
space1 | The LM ECS could use the LiOH canisters made for the LM (primary) as well as fitting the LiOH canisters made for the suit backpacks (PLSS) (secondary). I don't know if the Apollo 13 crew had already used the PLSS LiOH canisters when the fix was developed. As I understand it, an adapter was made for contingency use on later flights. Have a look if you haven't already seen a comparison of the LM and CM LiOH canisters. |
Andy Anderson | The following is quoted from the Apollo 13 Mission Report September 1970. The installed primary lithium hydroxide cartridge was used for approximately 27 hours (82 man-hours) following activation of the lunar module at about 58 hours. The secondary cartridge was selected at about 85 1/2 hours. During operation of the lunar module carbon dioxide removal system, the level was permitted to increase to an indicated 14.9 mm Hg. The primary cartridge is nominally rated for a usage capacity of 41 man-hours at 520 Btu/man-hour. The secondary cartridge, nominally rated for about 17.9 man-hours, was used for 8 1/2 hours (25 1/2 man-hours). This cartridge is identical to that used in the portable life support system. A second primary cartridge was installed and used for approximately 6 minutes, but for the remainder of the mission, command module lithium hydroxide cartridges were operated in a special arrangement. One side of each of two command module cartridges was covered and sealed with a plastic bag normally used to store a liquid-cooling garment. One corner of the bag was sealed to the inlet of the suit circuit hose. The cabin atmosphere then returned to the lunar module suit circuit through these supplemental cartridges by way of the two outlet hoses. The mass flow through this arrangement was partially restricted with tape to properly load the suit-circuit compressors. After approximately 20 hours of operation with two command module cartridges, an additional unit was stacked on each original cartridge to improve the carbon dioxide removal capability. With this supplemental configuration, when only command module cartridges were being used, the indicated carbon dioxide level was maintained between 0.1 and 1.8 mm Hg. This is an image of the other "mail box" that was installed in the tunnel rather than the more commonly portrayed image of the one in the LM. |
bthumble | Was watching Apollo 13 movie yesterday and it made me think. Was there any type of redesign so that both the CM and LM used the same size canisters in future missions? Editor's note: Threads merged. |
p51 | quote: Originally posted by bthumble: Was there any type of redesign so that both the CM and LM used the same size canisters in future missions?
Good question. Weren't all the other LEMs under construction by the time of Apollo 13's launch?I'd doubt the changed the entire design but would assume they had some manner of converter for these canisters from Apollo 14 on... |
mikej | quote: Originally posted by p51: I'd doubt the changed the entire design but would assume they had some manner of converter for these canisters from Apollo 14 on...
Somewhere I've seen pages from a flight plan or similar document (i.e., one which was flown in the Command Module) which contained instructions on how to make an Apollo 13-style adapters. It included drawings of what it would look like when done. Can't seem to locate that document, however. |
Headshot | Even though it makes little sense, I have to ask if NASA ever developed a kludge (for future missions) to use the round LM canisters in the CM? |
Kocmoc | On a related issue, I have heard the rumor that both PLSS's were brought back as ballast, but I can find no reference to this. Has anyone seen the post-flight ASHUR list that would confirm or deny this rumor? |
SpaceAholic | May not have appeared on the ASHUR list unless there was a requirement for post mission re-utilization or analysis. The CASHUR was prepared in advance of the flight and probably would not have accounted for offload previously unanticipated transfers of material from the LM. |
Robert Pearlman | It seems the two PLSS backpacks did not return, but parts of them did, based on a 2008 letter from Jim Lovell certifying a cut segment of fabric from his pack. I hereby certify that this PLSS Backpack piece was removed from the PLSS before we abandoned the Lunar Module on the way back from the moon on April 17, 1970. (I am assuming there would be no reason to remove pieces while in space if the full packs were also going to return to Earth.) |
SpaceAholic | PDF Pages 750, 751 mission transcript capture disposition of at least one of the PLSSs. |
Kocmoc | Thank you both. ------------------ Cathleen S. Lewis |
space1 | Does anyone know if any LM LiOH canisters were returned with the crew, as ballast or for study? |