MSC-07631 07. LOI, DOI, lunar module checkout

Cernan

The only thing leading up to LOI that had to be changed in the Flight Plan or in the Cue Cards, since we did a 2-hour and 40-minute clock update which by the way went perfectly, was the fact that I had to replot all the LOI abort parameters on the card. But the words came up very smoothly, and we just replotted the curve and changed the numbers. We had all our LOI abort constants and numbers for the new LOI configuration.

SPS burn - I thought the SPS burn was very smooth. We had an on time burn. The burn report came back to you, and the residuals and everything were just as nominal as could be. It was just a short little "g-thud," if you want to call it that, at ignition; throughout the burn, it went smoothly. Jack, you got anything about either one of the LOI or DOI SPS burns?

Schmitt

They were all auto shutdown. We covered the problems before.

Gravitational Effects on the Spacecraft Attitude - That was on rev 1, wasn't it, where we had the pan camera going and we had it all figured that we had one jet firing and the gravitational effects were supposed to keep the spacecraft within that dead band. Sure enough, it did. At least, we didn't get out of the dead band at all and didn't have to change the DAP at all on the first rev. This is to keep the jets from firing into the mapping camera.

Evans

Communications - We never had any problems with communications at all throughout the flight.

Cernan

PGA Donning - Our PGA donning practice was a worthwhile exercise. It takes a lot of work to get the suits unstowed and stowed, because putting the suit on in zero-g is just a little bit different. Unlike the previous flight or two, none of the three crewmen had any problem in donning or doffing their suits. I'd say donning is easier in zero-g than doffing. The CDR and the LMP helped each other with the zipping on every donning and doffing, as we've done in training. We had no problems at all. I'm glad that we were aware of the problems that Apollo 16 had. I think we were more conscious of the potential problem that existed when zipping the restraint zipper. We were conscious of it and had sort of trained in a direction to cover all bets on being able to zip up. I would say that in zero-g the zipper was a little bit more difficult to zip, but certainly I can't really say it was a problem for either one of us.

Schmitt

The only problem was that little blue donning aid always got in the way.

Cernan

Every time we zipped it, we hooked the zipper coming around.

Schmitt

One time, I can't remember whether it was on the surface or in orbit, I got some S'ing in the lower portion of your outer zipper, and we lost maybe 5 minutes while I worked that over. Other times, I learned that you just have to move through that smoothly, and it's no problem.

Cernan

Tunnel mechanics and pretransfer operations - They all went as advertised.

Schmitt

We might mention that we did take that extra film magazine over there. That was purely because that was preplanned in our minds, an extra 16-millimeter magazine, mag EE, because we felt that we just didn't have enough film to get the orbital CSM/LM activities in addition to the planned activities for descent/ascent and lunar surface.

Cernan

If you're going to use that film during that period of time, it's better to have it in the LM than in the command module, and if it weren't used, you could always bring it back and use it in the command module. That worked out fine. I think we used it all.

Schmitt

We used it but there was something wrong with the mag though.

Cernan

had a gear strip in the mag, apparently.

Schmitt

It showed a half a magazine of film usage, so we did something with it.

Cernan

The condition of the CSM thermal coating was excellent.

Schmitt

Cantu checks - We did have an S-band comm problem initially. I talked to some guys a little bit last night about it. As near as I can tell, it was primarily the combination of two things: (1) Up-link data dropouts which were causing the problem on the lockup, plus (2) some phasing, when I would switch antennas when they would just about have lockup. I think we're going to have to wait until we get with the communications people in the systems debriefings to really work that out exactly what was happening. It was a combination mainly of ground problems of getting lockup plus the unfortunate switching on my part.

The transfer and restowage of equipment were nominal. I can't think of anything right now that was a problem.

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.