MSC-07631 14. Transearth coast

Cernan

Passive thermal control was what I would call unusual attitude because of the UV/IR requirements. These unusual attitudes did two things. They required us to remaneuver the spacecraft several times and enter and exit PTC several, several times, which, in itself was not a problem, just additional coordination. Coincidentally, most of these particular PTC attitudes were within 30°, certainly 45°, of gimbal lock most of the time. We were looking at the red apple a good portion of the trip home.

Some of those attitudes where you actually were in attitude or PTC in these relatively unusual positions, change the equilibrium heat load on the spacecraft. RCS quad temperatures were all right, but you could see it in helium package temperatures and, most noticeably, you could see it on the change in condensation from the tall hatch to the forward hatch. The tall hatch eventually, for most of the way home, ended up to be very dry. The second day out on the way home, the center hatch got soaking wet to (the) point that we even took a dry rag and wiped off some of the latch components and some of the gearbox components, externally. Not that it did much good, but there was just that much water on there. I think this is all due to the PTC attitudes required for the SIM bay experiments on the way home.

Schmitt

It was cold in the spacecraft, too.

Cernan

Oh, yes, it was cold in the spacecraft.

Schmitt

Not as cold as the commander thought it was.

Cernan

Cold enough to warm it up, on the commander's orders.

Schmitt

We mentioned we warmed it up on the ground's suggestion of an extra inverter and going to MANUAL on the temp gain. I think we discussed that.

Cernan

Ron, all your REFSMMAT changes, your platform torquings , all those went very well, I thought.

Evans

They were great, went really well.

Cernan

All the way back home, it was just changing attitudes, changing attitudes, changing attitudes, with the exception of the EVA day, which we'll cover here shortly.

Evans

CSM EVA - On EVA prep, we really didn't have any problem. We didn't know of any at that point. The EVA prep went right down the line, essentially. It was well laid out within the experiments checklist. We checked things off as we went, and stayed pretty much on the timeline. We started about a half hour early, and finished a half hour early.

Cernan

We were a half hour early throughout the whole thing, and we lost that half hour in opening the hatch. We turned out to be exactly on time. Where we lost that half hour was on a comm carrier change.

Post-EVA - One thing that helped us immensely on what ended up to be, I think, a very fine entry stowage was that we backed off after EVA and took a good long look at the long-range stowage as well as the post-EVA stowage. We really started housecleaning, cleaning up the cabin, and effectively stowing some of the articles that were not going to be used any further in the mission for entry at that time. Our entry stowage really started with the EVA timeframe period, and I think that really helped us out in the long run.

The only change to the prechecklist and postchecklist was the order in which we doffed and donned suits. It was very evident there were certain convenient ways, because of the way the suits were stowed and the way that people fit into the checklist, that when we donned the suits. The commander was first, then the LMP, and the CMP donned last. It worked out very fine. The CMP had less work to do in his suit, which also aided him in the long run.

In doffing, the LMP was first, then the CDR and then, the CMP. That wasn't exactly the way it was called for, but that's the way it worked out. We stowed our suits in the L-shaped bag prior to putting the center couch back in. This was another good decision, I believe, in helping us get the suits stowed back in that L-shaped bag.

Evans

Cabin depress - No problems. Normal depress.

Hatch opening - Even though the cabin was completely depressed, we were reading zero pressure. As soon as I opened the hatch, there was enough residual pressure, or something, inside the spacecraft that it actually tended to pull the hatch out of my hand.

Cernan

Because your suit is bleeding into the cabin all the time, so you never truly get zero.

Evans

That's right, you never truly get zero. The dump valve was still open, and if I had not been hanging onto the hatch, it would have blown it all the way open.

Cernan

That's not unexpected because it's exactly what we had on the lunar surface. We completely dumped the LM. I'd still have to break that hatch loose and hold it open about 6 or 8 inches until things just vented. Then, I could let go of the hatch and open it all the way. If I didn't it would slam back, closed. It was basically the same thing. You have to open that door and really let things get down to zero.

Evans

When I opened the hatch, all of the little ice crystals started flowing out. A pen went floating by, and something else went floating by - wasn't quite sure what it was. There's all kinds of little particles and pieces that start coming out through the hatch.

Cernan

I looked specifically for the scissors. I didn't see any scissors go out that hatch. I hate to say it. Ron, I'd like to say they went out the hatch, but I sure didn't see them go.

Schmitt

Sure you didn't see them go?

Evans

I caught the one thing that started to go by me, and I put it in your pocket. Once all particles and junk were out of the way we pushed the hatch open. We disconnected the counter-balance with the tool E. So, that we locked the hatch in the open position, so I just shoved it open, it went beyond the center position and locked in the open position with no problem.

Egress - I had a tendency to float up against the MDC. I had to cautiously duck to get my face as close as I could to the bottom of the hatch in order to get the OPS past the MDC and get on out. TV and DAC installation worked fine. I could hang on with the right hand on the hatch, the great big D-handle on the hatch, with the TV pole in my left hand. Worked out real fine. Just stick it in there and line it up; make sure it was locked in, then climbed on up the pole to turn the TV on. I turned the back on. You couldn't see the light on the thing, but you could feel the camera running once you turned it on. You could touch it and you could feel it vibrate a little bit.

The lunar sounder cassette retrieval should be on the air-to-ground tapes. Most of it was no problem.

The pan camera cassettes were next. No problem on the pan camera cassettes. It's obviously a bigger mass, and it's quite apparent when you try to move that big mass around. It is heavier and it weighs more than the other things. It's easy to move, but it is it takes a little effort to get it started. You know that if you ever get it started in one direction and it's going to keep on going and you have to stop it. I just tried to keep it under control. Mapping camera cassette had the same problem I had in the SIM bay c2f2. That was getting the thermal cover off. It stuck underneath the mapping camera laser altimeter door. I gave it a big jerk and it came off.

SIM bay inspection - That's all covered in the air-to-ground tapes. TV/DAC removal again was real simple. You just had to squeeze the lever and TV came out. It was easy to hang on to with one hand and maneuver the TV around and point it toward the Moon. I didn't have to worry about shining it into the Sun. I tried to again hang on with one hand and point the TV around toward the Earth. The Earth was maybe 15° away from the Sun. I tried to be a little more accurate. When I did that I really lost control of try body position. I was trying to maneuver the camera. You need both hands to maintain your body control.

Comm during EVA was loud and clear for me throughout the EVA. There was a lot of background noise; I'm sure it was coming over the VOX circuit.

Cernan

It didn't appear to me that anyone on the ground had trouble reading you.

Schmitt

One thing we did because it was bothering us I turned the VOX sensitivity down about two notches. That really improved the comm performance.

Evans

I don't know if it made any difference or not, but I got the impression that it did help.

Cernan

Comm into the cabin was excellent. I never had any trouble understanding with that hissing in the background.

Evans

Ingress - It seemed to me it was easier than egress. For some reason, hatch closing was harder than I'd anticipated. Maybe this is the same reason in that I must have been exhausting into the cabin all the time. That hatch would come closed to within about an inch of closing on the outer edge. Then it took an effort to pull the hatch closed so you could activate the latching handle so that you could get the latches over center. Of course, once you got the latches over center, it was real easy, a couple more cranks on the hatch for closing.

Repress was normal.

Schmitt

All I did was work in the hatch area. I want to emphasize what everybody's always said that you do your best work when everything's going easy. Move yourself in small increments to where you want to go. You can turn and dip and raise yourself out. I think it's also useful for any hatch or port operation to have somebody available to push you out on your tether towards where you want to go. It just eases the operation. With the struts and everything available there, there was never any feeling there that I could not have a way to control my body position. Sometimes it took a few seconds to get it where I wanted.

The one thing, invariably, every time I went back inside I had the 90° disorientation for a few seconds until I got the perspective of the cabin again. I'd say okay, that's right. Then I would go back outside and come back in, and once again it seemed that cabin had rotated 90° to my perspective. It's just something that's no problem, it's just a change of perspective. For some reason, I experienced it several times. I guess the biggest problem working in that angle for me, attitude, was I had the Sun full face.

Evans

You had the Sun in your eyes most of the time.

Schmitt: It made it hard to look in detail to see what you're doing. You were clear image; you were there. I could see every major operation, but I could not see specific details.

Evans

I had no awareness whatsoever that I had an umbilical on my back. I never got the feeling that the umbilical was restricting my movements. I didn't even know that it was there, Did you observe at any time, did the umbilical ever get tangled around?

Schmitt

No, the umbilical was easy to tend. There may have been one. I had a vague impression that I asked you to hold up, or maybe I did not say anything, I just moved you away from a handhold or something. The umbilical didn't seem to slink around. You seemed to have everything you needed on it.

Evans

I did not even know it was there. Being tied to the umbilical does not restrict your movement or give you a feeling that it is restricting your movement at all.

Transearth - I did not see a light flash.

Schmitt

That evening I did see them again falling asleep.

Evans

I did, too.

Schmitt

So then, it was just that period during the actual experiment for some reason they were not visible.

Evans

We never really utilized the waste stowage vent to get rid of any odors out of that waste stowage compartment. It was always a crime if you were in that area, if you got real close to it.

Schmitt

The cabin generally turned over the atmosphere in pretty good style. It got saturated sometimes with gas and it took a few minutes to clear. The cabin did a good job.

Cernan

Flight Plan updates were super. The Flight Plan was excellent. Changes were held to a minimum, and we really did not change any part of the entire flight except a few dates, times, and attitudes.

Entry preparations began after EVA and continued all through the next day. We had very little final stowage to do on the final entry morning, just those things we had to leave unstowed until we got out of our sleep restraints. Basically, we just had to tie the big bags dawn. Final entry preparations went by the checklist. If anything, we stayed about 5 minutes ahead throughout the entire checklist, including separation and activation of the command module RCS and .05g, which came on time. Communications I thought were very good through this time. I understand the ground heard everything we said right through blackout. As soon as we came out, they still had ARIA, and they could still read us. We could have read them, but they never transmitted anything.

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Edits and errors by Eric Hartwell are licensed under a Creative Commons Attribution-NonCommercial-ShareAlike 2.5 license. The original NASA material is copyright-free.