After the problem realized when trying to put up three astronauts for an extended stay in the Apollo 13 LEM, namely that the square CM CO₂ scrubbers didn't fit in the LEM's slots, were they redesigned?

Apollo 13 "Mailbox" CO₂ scrubber adapter rig

  • 3
    $\begingroup$ A "simple" change in shape can have multiple knock-on effects (volume, flow rate, etc.), all of which would have had to be reviewed and approved by the configuration management board, which wasn't a fast process. Meanwhile, no work could be done on the spacecraft until the change was approved. The better option was to ensure that such an incident wouldn't reoccur. $\endgroup$ – John Bode Dec 16 '16 at 22:32

No, the scrubber design was not modified.

The Apollo 14 press kit has a list of the changes made after Apollo 13:

The major changes to the command/service modules include adding a third cryogenic oxygen tank installed in a heretofore empty bay of the service module, addition of an auxilliary [sic] battery in the service module as a backup in case of fuel cell failure, removal of destratification fans in the cryogenic oxygen tanks and removal of thermostat switches from the oxygen tank heater circuits. Provision for stowage of an emergency five-gallon supply of drinking water has been added to the command module.

(and several more paragraphs)

The file doesn't mention any changes to the CO₂ scrubbers.

A thread on Yahoo claims no changes were made, but offers no references. One of the posters there does say he has an Apollo 16 LM CO₂ canister, and it looks identical to the Apollo 13 items.

The Lunar Module, LM 10 Through LM 14, Vehicle Familiarization Manual (large PDF) shows a drawing of the Environmental Control System (page 3-55/page 89 of the PDF). LM 10 flew with Apollo 15. The drawing still has round covers for the scrubber canisters, like the photo below. LM ECS with captions

| improve this answer | |
  • 16
    $\begingroup$ There was no real need to unify the designs, given that after Apollo 13, a proven procedure to build an adapter was available. $\endgroup$ – Russell Borogove Jun 16 '16 at 3:59
  • 5
    $\begingroup$ In addition to @RussellBorogove I think it was also simpler to manufacture a properly built, ready to use adapter rig and stow it away. Also don't forget that during a mission going to plan the LEM was jettisoned before leaving lunar orbit. So on the journey home the LEM was not available as a life raft. So provisioning for keeping the CM functional in case of a SM failure was priority, since there'd not always be a LEM around to retreat to. $\endgroup$ – datenwolf Jun 17 '16 at 19:20
  • 2
    $\begingroup$ The film of Apollo 13 made more of a drama of the CO2 scrubbers than happened in reality. NASA had already developed the means of joining the two systems together well before Apollo 11 as part of their emergency "What if" planning. $\endgroup$ – MiguelH Oct 8 '19 at 9:15
  • $\begingroup$ @MiguelH source? $\endgroup$ – Sam Jun 12 at 9:56
  • $\begingroup$ @Sam it's a fair cop! I thought I'd read somewhere that nasa had already got this figured as a contingency plan. However, I cannot find that source, It does look like they created the solution on the fly. My bad. I would edited my comment above if I could! $\endgroup$ – MiguelH Jun 13 at 11:38

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy

Not the answer you're looking for? Browse other questions tagged or ask your own question.