A few questions cropping up as I drift towards the moon... When I do a P52 or a P23, am I actually changing anything in the simulation, or is it more of a "Hey, nice job on that P23, but we're going to keep everything where it belongs so you can't goof it up"? If I skipped doing all of the sightings, would it effect the outcome?
The P52s absolutely matter. The IMU in NASSP doesn't have any natural drift, but it is actually aligned by P51s and P52s so if your P52 aren't accurate then the AGCs knowledge where to point the spacecraft will not be very accurate.
P23s don't matter much in NASSP and didn't matter much during the actual missions. They were just practice for the case that the crew loss all communication with the ground and had to get back home on their own. They were always supplied with a fresh state vector from ground tracking after their P23 practice. And in NASSP P23 has a few issues, like the Earth having the wrong shape in Orbiter, so it's perfectly fine to skip the P23s. They also hurt my eyes when the split line-of-sight is active.
Second, when I do a P23 the spacecraft maneuvers to orient the optics towards the horizon or landmark selected. Does the spacecraft RPY ever settle down, or is it normal for it to "wobble" around the target in small increments seeming to constantly search?
A bit of that is normal behavior, the rates are never nulled 100% by the AGC, so a bit of thrusters firing now and then is expected.
Finally, when instructed to "null" the rates, it seems I can't ever get the rate indicators zero'd, I can only get them a little to one side or the other. Is there some magic key to make my RCS pulse smaller (besides MIN IMP). Thanks.
There is no magic key, only slightly to very cheaty ways to get your rates down. One way would be to switch to 0.1x time acceleration and the use the SCS to null the rates, as it doesn't suffer from computer delays at 0.1x. The very cheaty way would be to use the PAMFD; on the GNC page it has a kill rotation button which completely nulls your attitude rate. Useful for a beginner at P52 I guess.
Light CSMs and the LM in most cases do suffer from too much RCS firing when in auto or attitude hold mode. Partially that is due to the behavior of the RCS. When the vehicles get very light the AGC would like to fire the RCS for a very short duration, shorter than 2 or maybe even 1 timesteps in the Orbiter simulation at 60 frames per second. That's where some of the attitude control issues come from. I have an idea for a solution, but it will require a while before it will be done. And it will mainly help the LM ascent stage, not so much your case with a, I presume, still quite heavy CSM.
I did them for the experience.
