Apollo 13 Lunar Surface


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Building an Apollo 13 LiOH Canister Adapter

Compiled by Hermann Dür and Eric Jones.
Last revised 30 September 2012.


In the aftermath of the oxygen tank explosion in the Apollo 13 Service Module, the Command Module was largely powered down to preserve it for re-entry and the LM served as a lifeboat.  Among other things, the LM Environmmental Control System would have to keep carbon dioxide levels at acceptable levels for the remainder of the mission.  At the time of the explosion there were two lithium hydroxide (LiOH) canisters - a primary and a secondary - in the LM ECS, which, together, had been designed to handle the carbon dioxide output of two people for about 30 hours.  What was needed was a means of dealing with the output of three people for at least four days.  Additional LM canisters were hopelessly out of reach in the MESA.  There were plenty of CM ECS canisters, but they wouldn't fit in LM ECS.  Houston went to work devising a means of drawing cabin air through a CM canister into the ECS using only materials available in the two cabins.

            from S70-35013, Deke showing LIOH adapter to management

Deke Slayton (check jacket) explains the adapter devised to make use of square Command Module lithium hydroxide canisters to remove excess carbon dioxide from the Apollo 13 LM cabin. As detailed in Lost Moon by Jim Lovell and Jeffrey Kluger, the adapter was devised by Ed Smylie. From left to right, members of Slayton's audience are Deputy Director/Flight Operations Howard W. Tindall (standing), Director/Flight Operations Sigurd A Sjoberg, Deputy Director/Manned Spaceflight Center Christopher C. Kraft, and Director/Manned Spaceflight Center Robert R. Gilruth. 15 April 1970. (Click on the image for a larger version.)

As-built adpater in the

As-built  adapter in the LM cabin. (Click on the image for a larger version.)

A13 Mission Report Figure 6.7-1

Figure 6.7-1 from the Apollo 13 Mission Report.  This figure wrongly shows two CM canisters stacked and taped together.  In fact, the crew was instructed to build two units, each incorporating a single canister.  (Click on the image for a larger version.)

2012 Replica

In 2012, Journal Contributor Hermann Dür decided to make a replica of the adapter built by the Apollo 13 crew, using a Command Module Lithium Canister he has in his personal collection, together with other suitable materials.  He used the images above for guidance, but primarily followed the instruction given to the crew by CapCom Joe Kerwin.  Before we present the relevant air-to-ground, the two following images show the replica viewed from all sides.

Series of views during
            rotation of the unit around one axis

Views of the replica from various locations  while the unit is rotated around an axis parallel to the hose. Selected images are used to illustrate the instruction set presented below.
(Click on the image for a larger version.)

series of views during
        roation around an axis perpendicular to the first

Series of views during a rotation around an axis perpendicular to the first.
(Click on the image for a larger version.)


The transcript extract that follows comes from the Apollo 13 Technical Air-to-Ground Voice Transcript, starting with PDF page 418 (document page 411).  The transcript has been checked and corrected using audio recording 420-AAA_Track-3, starting 1 hour 26 minutes 06 seconds after the beginning of the audio clip.

Times are given as "dd hh mm ss".

03 18 08 43 Kerwin: Okay, Jim. The way I thought it might be best to do it would be to have you gather the equipment and let us talk you through your procedure while you do it. Now, maybe you could give Jack the headset and - and - get the equipment together, and then we'll talk you through the procedure. I think it'll be a little easier to do that way than if you tried to copy it all down - and then go do it.

03 18 09 11 Lovell: Okay. Do you have any equipment listed? I'll just get it and give it to him and I can just sit here where I am.

03 18 09 17 Kerwin: Okay. I think the equipment you'll need will be two command module lithium hydroxide canisters, a roll of the gray tape, the two LCGs  because we're going to use the (plastic) bags from the LCGs, and one LM cue card - one of those cardboard cue cards - which you will cut off about an inch and a half out from the ring. Now, I think that's all we'll need. Over. (Pause)

03 18 10 03 Lovell: Okay (garbled) Okay, Houston. (Long Pause) Hello, Houston.

03 18 10 25 Kerwin: Go ahead, Jim.

03 18 10 28 Lovell: Okay. That's two lithium hydroxide canisters, one roll of that special gray tape, two LCGs which we're going to use the bags from, one LM cue card and (garbled)

03 18 10 53 Kerwin: Okay. That's affirmative, Jim. If you'll just cut the cue card, which is a handy piece of stiff paper the right size, about an inch and a half from the rings. Just cut off the ring holes, in other words, and you'll have a card about 11 inches long and probably 6 inches wide, something like that.

03 18 11 19 Lovell: Okay, fine. I'll have Jack gather up the stuff.

03 18 11 22 Kerwin: Okay.
[Jumping ahead to 1 hour 38 minutes 49 seconds after the start of the audio clip.]
03 18 21 26 Lovell: Okay, Houston; Aquarius.

03 18 21 32 Kerwin: Yes. Aquarius, Houston. Go ahead.

03 18 21 37 Lovell: We have gathered the material, and I can put Jack on the headset and he can copy the instructions. Or could I copy it to give them to him, or do you think they're too detailed?

03 18 21 55 Kerwin: Why don't you put him on the headsets, Jim, and I'll read it out to him.

03 18 22 02 Lovell: Okay. (Long Pause)

03 18 22 30 Swigert: Okay, Joe.  I'm on.

03 18 22 33 Kerwin: Okay, Jack. Did anybody ever tell you that you got a 60-day extension on (filing) your income tax. Over.

03 18 22 42 Swigert: Yeah. I think - I think somebody said that when you are out of the country, you get a 60-day extension.

03 18 22 50 Kerwin: Okay; right. Okay. I'm ready to start into the procedure. When you answer me back, speak up - speak up into the microphone, because our downlink is pretty noisy. The first thing we want you to do, and we'll do this on one canister, and then let you go ahead and repeat it on the second. So take one of the LCGs and cut off the outer bag by cutting along one the heat seals. Do it carefully and close to the heat seal, because we may have to use the outer bag if we damage the inner bag. So go ahead and do that, and then we'll do the next step. (Pause)

03 18 23 37 Swigert: Okay. Take an LCG, cut the outer bag by the heat seal. Be careful not to damage the inner bag. Right? (Pause)

03 18 23 46 Kerwin: Right. Just cut along one side.
[Comm Break]
03 18 24 50  Swigert: Okay, Houston, Odyssey (the name of the Apollo 13 Command Module) - (correcting himself) or Aquarius. We've done that.

03 18 24 55 Kerwin: Okay, Jack. Now - now remove the inner bag from the outer bag, and cut the inner bag, also, along one of the heat seals down one side. (Pause)

03 18 25 15 Swigert: Okay. Remove the inner bag from the outer bag, cut the inner bag along the heat seal along one side.

03 18 25 22 Kerwin: Okay. That's correct. Do that, and report. (Long Pause)

03 18 26 20 Swigert: Okay, Joe. We've got that done.

03 18 26 22 Kerwin: Okay, Jack. Now you can put the LCG itself; that is, take it out of the inner bag, put it in the outer bag, and stow it some place; we recommend U-1, but you can stow it wherever it's convenient.

03 18 26 40 Swigert: (Garbled)  outer bag (garbled) and re-stow it back in U-1. (Pause) Okay, Joe. We've got that.

03 18 26 50 Kerwin: Okay. Now pick up one of the lithium hydroxide canisters, and let me describe which end is which. It's approximately square on one - one of the vented flat ends, has the strap, and that end we call the top, the end opposite we call the bottom. Is that clear? Over.

CM LiOH canister: top (left) and bottom (right)

Command Module LiOH Canister: "top" (left) and "bottom" (right).
Image downloaded from
Historic Space Systems.
(Click on the image for a larger version.)

03 18 27 21 Swigert: Right. (Long Pause) Okay. I've got it, Joe.

03 18 27 37 Kerwin: Okay. Now then, we're - we want you to take the tape and cut out two pieces about 3 feet long, or a good arm's length, and what you're - what we want you to do with them is to make two belts around the sides of the canister, one belt near the top and one belt near the bottom, with the sticky side out; wrap it around, sticky side out, as tight as possible. It'll probably take both of you to get it nice and snug. Over.

03 18 30 01 Swigert: Okay, now … (Long Pause)  Okay. Now we've got to make the belt real taut here. (Pause)

03 18 30 23 Lovell: How's that?

03 18 30 35 Swigert: Real tight. And then (garbled) bottom.
[Comm Break]
03 18 33 13 Swigert: Okay, Joe.

03 18 33 18 Kerwin: Okay, Jack. Did you have …

03 38 33 19 Swigert: … Hey, Houston. Are you reading?

03 18 33 24 Kerwin: Jack - -

03 18 33 25 Swigert: - - We've got the two belts around the top and the one around the bottom all done.

Belts labeled on replica

The locations of the belts are indicated.  At 03 18 49 20, after the inner LCG bag has been put in place, Jack will add strips - sticky side down - to the outside to secure the bag.  These outer strips obscure our view of the inner belts.  (Click on the image for a larger version.)

03 18 33 30 Kerwin: Okay, fine. The next step now is to anchor that tape; and the way we want you to do that is to cut about a 2-foot length off the roll and then tear it lengthwise so that you have two strips about 2 feet long and about a half an inch wide. And you'll wrap those around the canister at right angles, more or less, to the tape that you've got so that it goes across the top and across the bottom; and when it goes across the top and the bottom, put it so that it's outboard of the center hole and try to get it over one of the ridges between the screens, so that it won't block the flow. Is that clear? Over.

03 18 34 15 Swigert: Yeah, Joe. Very good.

03 18 34 17 Kerwin: Okay. Press on.

03 18 34 22 Swigert: (To Lovell) Okay. I've got to cut (garbled) right here and we'll tear it lengthwise in half; and I'm going to go around right here at this ridge all the way around at right angles and anchor this tape down.  (Pause) Yeah.

03 18 34 46 Swigert: Joe, just to clarify that: sticky end down? Right? On the tape that I am putting on now?

03 18 34 54 Kerwin: I didn't quite copy that, Jack. Say again.

03 18 34 58 Swigert: Okay. That will be the sticky end down on the container, right?

03 18 35 05 Kerwin: Oh, that's correct. I forgot to say that. That's right. (Long Pause)

03 18 35 33 Swigert: (To Lovell) (Garbled) hold that one right here (garbled) set it.
[Comm Break.  Note that Joe did not tell Jack that the two anchor tapes should be parallel to one another, thereby keeping opposite ridges on the top of the canister clear for installation of the arch.]
02 18 37 28 Swigert: Okay, Joe; Aquarius. We've got that done.

Detail from 8929 showing securing tapes on the Aquarius

Anchor tape locations labeled on the unit built on-board Aquarius.  At 03 18 52 47, after the bag and arch are in places, they will add four strips of tape to secure the bag more snugly.  Two of these 'securing' tapes will go over the anchor taps and the other two at right angles, one on either side of the central hole.  The fact that the vertical 'securing' tapes  overlap the anchor tapes is particularly evident near the bottom of the image. (Click on the image for a larger version.)

03 18 37 32 Kerwin: Okay.  Jack, the next step is to get the EVA cue card and use it to form an arch over the top of the canister; just tuck one short end under one ridge on the top the other one against the ridge on the other side so that it forms a rounded arch over the top of the canister. You see, Jack, what we're going to do is slip the bag over this whole assembly and the cue card will serve to keep the bag from being sucked down against the screens. Over.

03 18 38 10 Swigert: Okay. I got the idea.

03 18 38 13 Kerwin: Okay. And when you've done that, to hold the arch in place, just run a strip of tape across the sides of the … (correcting himself) that is, across the top of the arch, and anchor it down to the sticky strips along each side.

03 18 38 31 Swigert: Okay. I got the idea. Okay. Let me just repeat
it here. Take a cue card, form an arch over the top, bringing it under the sides here. When we're through, run a piece of tape from the sides across the top of that to anchor to the other side.

03 18 38 51 Kerwin: That's correct.

03 18 38 56 Swigert: Okay. In work. (To Lovell) The top. Across the top. (Garbled) Looks like you're going to have to cut the cue card slightly. (Long Pause) Doesn't have to be real (spelling is correct) exact all the way across. We can just take the scissors and cut off the edge here. The only thing this does, Jim, is prevent this (bag) from being sucked down into the container. (Long Pause) (Garbled)
[Comm Break]
03 18 43 34 Swigert: Okay, Joe. We've got that arch built, and it's all taped in securely.

Compare canister top with replica

Installed arch on the replica (right).  The ridge that surrounds the top of the canister is labeled on the replica and an unmodified canister (left).  (Click on the image for a larger version.)

03 18 43 41 Kerwin: Okay, Jack. The next step is to stop up the bypass hole, which is the hole in the center of the bottom of the canister; we want to stop that up because we don't want to bypass the flow; and I forgot to tell you to get something to stick in that hole. We recommend that you either use a wetwipe, or cut off a piece of sock and stuff it in there, or you could probably even crumple up some tape and use that. Over.

03 18 44 13 Swigert: Okay. We'll start plugging up the bypass hole.

03 18 44 17 Kerwin: Okay.

03 18 44 18 Swigert: (To Lovell) Plug that hole. We can either - we can put some - he says - Let's cut a piece of your towel there.

03 18 44 27 Kerwin: Sounds good.
[Comm Break/  The audio clip is missing about two minutes of the original recording.  The next transmission begins about about 2 hours 4 minutes 12 seconds into the clip.]
03 18 47 14  Swigert: Okay, Houston; Aquarius. We have the bypass hole all plugged up.

03 18 47 21 Kerwin: Okay, Aquarius. The next step is take the inner LCG bag that you cut open, and slip it over the top of the canister, when you do that, orient it so that the ears of the bag, that is, the corners should stick out on the closed end - are oriented along the open ends of the arch, because we're going to snip one of those corners to stick the hose in. Pull it down until it fits snugly over the arch. Over.

03 18 47 56 Swigert: Okay, Joe. Slip the bag over the canister so that the arch is at the bottom of the bag and that the ears (after struggling to find the right words) would be at the sides of the arch.

03 18 48 19 Kerwin: Depends on what you mean by sides. Over the open ends of the arch.

03 18 48 26 Swigert: Right, the open ends of the arch.

03 18 48 28 Kerwin: Okay.  (Long Pause)

03 18 49 17 Swigert: Okay, Joe. We've got that done.

03 18 49 20 Kerwin: Okay. Now press the bag against the sticky belts that we put on the sides of the canister. If there is any excess material, just kind of pleat it, so that it makes a fairly tight seal, and then take another 3-foot strip of sticky tape and wrap it around the outside of the bag opposite (that is, "over") the bottom sticky belt - to make a nice tight seal.

03 18 49 50 Swigert: Okay. I'll do it. Okay. (To Lovell) Now they want two strips around here to make a tight seal.
[Comm Break.  In a labeled view of the replica, note that the strip they are putting over the bag at the bottom of the canister is on top of the two anchor strips put on earlier. As they tell Joe next, they also put a strip around the top of the canister.  Jack's next transmission starts 2 hours 10 minutes 28 seconds into the clip.]
03 18 52 38 Swigert: Okay, Joe. We've got the canister inside the bag, two strips around the sides of the bag, real tight, and both sealed.

03 18 52 47 Kerwin: Okay; real fine. Now there's probably a couple of inches of excess bag sticking our around the bottom of the canister. To prevent this from sucking in against the bottom screen, we'd like you to trim it off with the scissors, and when you've done that, we'd like you to cut two more strips of tape about 12 inches long or so, cut the - tear them lengthwise to get four pieces 12 inches long and 1/2-inch wide, and then use those four strips to secure the bag by passing the strips from the sides of the canister - outside the bag -  around the bottom of the canister and back up the other side, and when you do this, just as you did on the top, make them go outward of the hole and in between the screens. Over.
[In a detail from AS13-62-8929, portions of the ragged edge of the bag left behind by Jack's trimming are labeled.]
03 18 53 42 Swigert: Okay. You want me to trim the excess material that's sticking off here; trim it at the edge of that canister? Or do you want any excess left over?

03 18 53 52 Kerwin: No, you don't need to have any excess. Just trim it approximately level.

03 18 53 59 Swigert: Okay. Let's do that first.

03 18 54 01 Kerwin: Okay. (Long Pause)

03 18 54 58 Swigert: Okay. Now, Joe, you want to cut four strips, 12 inches long each, 1/2-inch in diameter. Tape that along the outsides of the bag across the ribs.

03 18 55 15 Kerwin: That's correct, Jack. That's just for additional security on the bag. When you get those done, you'll have two strips going one way, and the other two will be perpendicular to them.
[Comm Break. the next transmission starts 2 hours 16 minutes 39 seconds into the clip.]
03 18 57 58 Swigert: Okay, Houston; Aquarius. We've got the four strips in place.

03 18 58 03 Kerwin: Okay. We're in business now with the bag, and the next step to perform is to get ready to put the red suit hose - either the commander's or the LMP's because we're going to want you to have both of these made up eventually - into the top of the bag. And to do that you, first of all, have to assure that the red hose is separated from the blue hose. I don't know whether this has been done already, but if it hasn't, what you have to do is cut the outer Beta-cloth sheath down the full length of the hoses and then also cut the rubber ties that secure the two hoses together, and the hoses should come apart and the Comm cable should come off. Over.

03 18 59 04 Swigert: Okay.  Take the - I'm going to want to separate the red hose from the blue hose by cutting this Beta-cloth sheath.  Okay.  That's in work.

03 18 59 15 Kerwin: Okay.
[Comm Break]
03 19 00 52 Swigert: Okay, Houston; Aquarius. I have the LMP's red hose separated from the others.

03 19 01 00 Kerwin: Okay. Real fine. Now the next step is to cut a diagonal hole in one ear of the plastic bag near the arch. You can pick either one and cut about a 1-1/2 or 2 inch diagonal hole, big enough to slip the red hose through. And when you've done that, you'll just slip the red hose through so that it goes about to the center of the canister. It's not critical except that the opening should be down; and then tape the bag to the hose where it goes in so that it's nice and snug. Over.

03 19 01 40 Swigert: Okay. Copy that. We want a 1-1/2 inch hole right here at this ear, and put the hose in here, end down and toward the canister; and then we tape the seal around here. (Long Pause)

03 19 02 10 Swigert: Let's try it. (To Lovell and/or Haise) We can always make it bigger if we have to. Fred, get those (garbled). (Long Pause) Got to come in towards the center, all the way to the center. No, no.
[Comm Break]
03 19 06 17 Swigert: (To Lovell and/or Haise) Yes. I can't get those big knobs.
[Comm Break]
03 19 08 39 Swigert: (To Lovell and/or Haise)  All we have to do is (garbled) tape around here (garbled) tight fit. (Garbled)

03 19 10 18 Swigert: Okay, Houston; Aquarius.

03 19 10 20 Kerwin: Aquarius, Houston. Go ahead.

03 19 10 26 Swigert: Okay. Our do-it-yourself lithium hydroxide canister change is complete. Joe, the only thing different is that our arch on this piece of cardboard is not big enough to position the red hose with the inlet down.  The inlet to the red hose is lying on its side, but I think it'll still work.

View of hose insertion under arch of replica

View of a hose inserted through a slit in one 'ear' of the bag on the replica, and then pushed in far enough to reach the center of the canister.  The bag material was then taped securely around the hose. (Click on the image for a larger version.)

03 19 10 53 Kerwin: Okay, Jack. I concur. I think it'll work, too. There's one step that I omitted, which you can do now quite conveniently; and it's this. Where you stuffed the towel in the bypass hole on the bottom, we recommend that you cut a few short pieces of tape and just tape that over so it doesn't fall out. Over.

03 19 11 17 Swigert: (To Kerwin) Okay. Will do. (To Lovell) Jim, I've got one more little thing to do, and that's (to) seal that (garbled).  (Long Pause) (To Kerwin) Okay, Joe. That's done.

03 19 12 30 Kerwin: Okay, Jack. Now the remaining steps are simply suit-loop configuration steps to get this thing into full operation; and our ECS people want to
hold off on that until the (LM LiOH) canister you're working on gets to 7.6 millimeters of mercury, which will probably be another 45 minutes or an hour. We're reading 4.7 now. So what we'd like you to do in the interim is to set up the second command module canister the same way you just did the first one, using the commander's hose, and get that all set and probably about that time it'll be time to switch over.

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