MSC-07631 11. CSM circumlunar operations

Evans

Operation of the spacecraft - The CSM solo operations are essentially nominal. One time on the back side of the Moon, after I'd done the zodiacal light, where you had to switch to CMC free during the pass to prevent any jett fires and then you switch back to auto, I missed the switch back to auto and proceeded on into the waste-water dump and urine dump. Unfortunately, I locked the spacecraft control switch and CMC free. The waste-water dump evidently puts in quite a torquing force or perturbates the spacecraft such that I was getting a master alarm with the gimbal lock light. As soon as I had the caution and warning, I checked back and found that it was getting close to gimbal lock. I switched to SCS, and it backed away from gimbal lock. Then I pushed back to auto and got back to P20 attitude.

Navigation, normal state vector updates - When the down range error got to about 30,000 feet, I let go and shifted up a state vector. The RQ model being used over in mission control to project the orbital decay didn't work quite right, so I ended up with the orbit not decaying down to the circular orbit prior to the plane-change burn. I ended up making the high adjust maneuver or trim burn to bring the orbit down to 63 by 63. The trim burn was performed about an hour before the plane-change burn. Trim burn was a 9-foot-per-second RCS burn.

LM acquisition - Nominal in all respects. The thing that is somewhat of a surprise to me, and I should know this, you get molded into a false sense of security by doing rendezvous in the CMS. You look through the telescope, and there's a big blob of light. The telescope is indicating where the LM is. In the real world you look in the telescope, and you can't see. It's very hard to see 150 miles away. As a matter of fact, the LM was at about 80 miles before I actually saw the flashing light in the telescope. As I went into darkness, I could see the flashing lights in the sextant. I did not get LM acquisition prior to going into darkness, and I did not have it in the first part of the rendezvous. I did not have the Sun in the sextant. There was no Sun in the telescope, and it was about 3 minutes prior to spacecraft sunset before I had the Sun in the sextant and in the telescope. I could not pick up the LM in either the sextant or the telescope. Once I had picked the LM up in the sextant, I had no problem from then on.

Update pad and alignments - No problem. We kept the P30 pad in R-11 where it was always available in case I needed it. I always realigned to different REFSMMAT. In translunar coast or transearth coast, I always switched to SCS minimum dead band and gyro torqued. As I picked stars on the dark side of the Moon, I would coarse align to the new REFSMMAT. It might be interesting to note that on PDI day prior to LM separation, there's a P52 scheduled about the same time the LM crew is getting suited up. I delayed the P52 until they were in the Challenger. By this time, the SEP attitude pointed the optics right down to the Moon. The PICAPAR didn't work, so I just started the spacecraft roll and kept recycling the 404 alarm until I finally was able to get it to work. After I got to P52, I maneuvered back to the LM sep attitude.

Lunar sounder boom deployed - We had a little test to extend and retract the booms. Extend worked okay. Retract and HF 1 never did get the gray. The antenna retracted to the extent that there was no problem for RCS or SPS burns. In trying to retract prior to plane change, we looked out the window and could see it start back in. The extensions on HF 2 - Number 1 always extended all right, but number 2 would go out for a little way and stall. We retracted it for 5 or 10 seconds and then switched it back to extend until it deployed fully. At any rate, with a little bit of work, we got the booms in and out.

Monitoring lunar activity - I did not attempt to monitor it but I could put on VHF and talk to them. I was usually operating during VOX during the solar periods, so I just left the VHF off. Prior to lift-off, we had MSFN relays activated that worked real fine.

Lunar sounder pad experiment - No problems. Everything worked fine.

SIM bay daily operations - On the mapping camera, the first extension took longer than anticipated, so it was elected to leave the camera extended throughout that day. It took about 4 minutes to retract when we retracted it. On one of the mapping camera oblique passes where we were starting at the spacecraft sunrise terminator, I went to operate and got the barber pole. The Malfunction Procedure is to go to standby, which we did. We left it in standby until we just about came up to AOS. At that time, the barber pole disappeared. Evidently it was caused by the mapping camera area being too cool. And as soon as I got the gray indication, I went to operate and had no problems the rest of the time. Laser altimeter - It seemed to work fine. There were no anomalies.

Pan camera - There were no anomalies that I know of with the pan camera. There was some concern at one time if it was getting a little warm in there and also some concern as to whether the lens had really stowed.

UV spectrometer - As far as I know, we got outstanding data. The information that was passed up to me indicated that there isn't as much hydrogen in the atmosphere around the Moon as was originally thought.

IR scanning radiometer - It worked real fine. We're still getting good information, and we were getting good information on the way back. It was on most of the time.

The SIM bay photos - Let's see, that means photographs by the LM. It seemed to work all right. The Challenger was easily maneuvered around to the right viewing attitude. They got some good pictures. Sunlight was okay.

Dim light photography - The dim light photography was the zodiacal light and the solar corona. It was okay.

Terminator photos - Hopefully, those are going to come out. I used a lot of Nikon film for terminator photos. We should have a lot of 35 mm stuff that was not planned or not scheduled in the Flight Plan. We used the Nikon with a red filter and a blue filter and took three shots with the red filter and three different shots with the blue filter of the landing site area. We also used two different polarizing filters in one direction and then in the other direction. That information should be in the Flight Plan. In each case, the zodiacal light with the filters worked out real fine. The timing and the settings worked correctly. I've got it noted in the experiment checklist that I had the wrong setting for half a second. I ended up on the 1-second mode. I think that was in the polarizing part. In any event those pictures should be good. In sketching the zodiacal light as you come up to the spacecraft sunrise, I think we probably didn't get the longest streamers that are just half a second or quarter of a second prior to the Sun popping over the horizon. In each case of the zodiacal light passes, the sequence ended 7 to 10 seconds prior to spacecraft sunrise. I think we probably missed the longest streamers. I didn't really observe this phenomena until the last day of lunar orbit and didn't have the opportunity to take a hand-held target of that particular phenomena.

Solar corona - The sequence worked real fine, no problems.

Earthshine photography - We worked it differently than it is indicated in the experiment checklist. I used Aristoteles and Copernicus starting out with a 1 second and taking two 1-second exposures. As we rotated around about every 30 seconds, it ended up a little closer than I thought. We were passing up the target too fast because we'd never get every- thing. The timing sequence may not be correct. It may not be exactly 30 seconds between each one. We would cycle down the exposure setting to 1 second, 1/2 second, 1/4 second, 1/8 second, and 1/16 second on Aristoteles and Copernicus. We'd leave it on one-sixteenth of a second following Copernicus and switch over to window three and pick up Reiner Gamma and do the same type of sequence. Then we stopped on 1/8-second exposure and carried it out until the end of the film mag.

Orbital science photography - It worked according to the Flight Plan We would have the initial setting, and on the orbital monitor charts, we would have the inpoints and then pick out specific craters and have these noted on the chart as to change settings. I did notice that it is very easy to bump and change the camera settings as you bounce around in the spacecraft - trying to keep track of the camera pointing as you try to maintain your own equilibrium. A couple of times at the end of a particular sequence, I noted that it had changed from what I had started with. The orbital science photography was accomplished with no particular problems other than trying to maintain a constant camera setting. We had two magazines of what we call CM option or option-photography colored film. Those two magazines were completely filled up with just targets of opportunity.

Plane change 1 - I previously mentioned the trim burn part of plane change 1. Plane change 1 was a little larger than anticipated because of nondecay of orbit, Plane change 1 is where I had 0.7 ft/sec and it seems to me like an X. I did not trim it because we were only trimming Y. There was also a plane change where I ended up with a different roll because the pan camera was looking right into the Sun. No real problem. If I were going to trim anything, I would trim Y and Z just to make sure I didn't perturbate the apogee and perigee orbit. To keep the pan camera out of the Sun, I went into P40 trim and utilized that roll angle. Communications were outstanding. Maneuvers done to support the lift-off presented no problem.

Rest and eat periods - I never got to sleep on time. It just took a great amount of time for one man to go through that Presleep Checklist - to go down and chlorinate the water, take the panel off, pull the return valve and clean the hoses - it just takes a lot of time to get it all done. But, there's no real problem.

TPI backup - My TPI solution agreed quite well with the Challenger, no problem.

Midcourse backups - I ran into a bit of a problem. I ended up with 5 ft/sec as a Z-value, and the LM ended up with 1 ft/sec, I don't understand why there's that much difference between the two midcourse solutions. Of course, the Challenger made all the burns during rendezvous and braking, so I didn't have any problems there.

Prep for docking - There is no time to get all the cameras and things squared away prior to going into rendezvous, so I strapped the TV monitor to the XX strut by the CDR's couch and utilized it during the rendezvous and braking phase or final phase of the burn. I used a P79 to point the X-axis out the LM. And once it got close, I essentially pointed the spacecraft such that the LM was always in the center of the TV field of view while coming in for docking.

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.