LM PGNCS

[grummanonewire]

So Ive been hopping around in some scenarios on the stable builds mainly the Apollo 11 and Apollo 9 I wish we had o nes for Apollo 10 but that's another story and im sure may be in work

what I am curious about is are there any tutorials out there on how to do a P52 in the LM

and how about AOHV2 for the LM ?

 

[MrFickles]

It's similar to a P53/54 in the CSM where you maneuver the entire spacecraft in order to establish the position of the star. The difference between a CSM P53/54 and LM P51/52 is the way a star is marked.

In the CSM you just align the COAS with the star and hit mark once. In the LM it's a little more work, you "rotate" the star around the AOT and repeatedly hit mark X and mark Y as the star passes through the respective axis on the AOT.

Let me show you what I mean.

First things first.

Start up P52 and just run through it as if it's a CSM P52 until you reach a flashing V01N70. This is the first star used for the alignment. First thing you'll realise is that the star code has 3 numbers instead of 2.

00ABB
A - AOT detent code, make sure this is 2, I'll tell you why in a sec.
BB - star code (either auto selected or manually input)

hit PRO

You'll now be greeted by a flashing V50N18. This auto maneuver will point the AOT directly at the star.

hit ENTR

you'll see the first star code again, make sure this is the star that the AOT is pointed at.

hit PRO

You'll see a flashing V54N71, this is telling you that the LGC is waiting for a MARK from us.

Now, the reason why I said to make sure the detent code earlier was '2' for front detent, is that pitch and yaw directly correlates to where the AOT is pointed at. Pitch up to point the AOT up, yaw left to point left, and so on... Start off by switching MODE CONT PGNS to ATT HOLD and pointing the AOT slightly away from the star.

enter V76E on the DSKY to switch off attitude hold DAP.

Look through the AOT, you should see some straight lines and 2 spiral lines. Ignore the spirals and the 'V' shaped lines. We are only interested in the vertical line (Y axis) and the horizontal line (X axis).

Maneuver the LM to have the star on either X or Y axis of the AOT and mark that axis.

Then, do the same with the other axis. This constitutes 1 mark. Do a total of 4 or 5 marks.

Hit PRO

You'll see flashing V01N70, this is the 2nd star code. Repeat the marking process.

Once you've marked the 2nd star 4 or 5 times, when you hit PRO, you'll see your star angle difference.

From here on out, the procedure is the same as a CSM P52, and remember to enter V77E to turn the attitude hold DAP back on after P52.

Hope this helps.

 

[grummanonewire]

Got the P52 down I needed to read and explore some on my own and trying by running instead of crawling usually does not work well however I kinda learned from Military training to get to a point of understanding then basing everything off of that single point of knowledge


Anyways Im in the Lunar ascent checklist and running the P57 and Ive got how the AOT crosshairs worked out or understanding of how it works so I think now I am at the part of getting the mark to the LGC im stuck at the entering the cursor position do I need ot enter that into R2 or R3 manually or ?

 

[meik84]

Mission Number? Later revisions of Luminary had a somewhat different (easier/more user-friendly) P57.

 

[grummanonewire]

Apollo 11 Lunar liftoff prep T122+14 min
I can get the alignment and the star and the gyro angle but does the LGC sense the gyro angle or do I have to input that into the dsky and if I have to input it
What register ?
or do I need to do a Y and an X mark and if so what register for what axis and the verb to enter

 

[meik84]

does the LGC sense the gyro angle or do I have to input that into the dsky

What gyro angle? All IMU-angles P57 displays are for information only (at best, you can confirm or reject them). The whole torquing around for gravity measurements and realignment is done automatically; no user input required (ok, PRO to start).

I need to do a Y and an X mark and if so what register for what axis and the verb to enter

I guess you are at V54N71, right? As the LGC says:'Mark X or Y on selected star'. The most convenient method to do so is:
1. Put the cursor (those V shaped lines in the AOT) on the star.
2. Press MARK X or MARK Y (which one doesn't matter).
3. LGC will switch to V06N79. Key V24E.
4. R1 will blank. Enter the angle the AOT shows, but beware: it's in hundreds of degrees, so 1138something on the AOT has to be entered as +1138X. The last digit is a rule of thumb thing. The real AOT had a fine scale on the last digit, ours hasn't. So use good judgement. And don't forget the '+'.
5. R2 will blank after ENTR. Place the spiral on the star and enter the angle again. DO NOT MARK!
6. You're done. Key PRO to finish marking on this star or key V32E to do more marks on the same star.

 

[grummanonewire]

That worked Im still unsure of accuracy of all of this but I was back when I was doing my first few P52s in the csm so

 

[meik84]

According to the Apollo 11 mission report, they had star angle differences from 0.07° up to 0.15°. So all balls in N05 doesn't seem to be realistic...

 

[grummanonewire]

just starting to play around some more

setting up mission timer in the before PDI dat +94 hours im at the LM activation point and cannot get the Mission timer to light up followed the checklist and I am still on lo volt taps

 

[meik84]

Resp. cb (panel 11) in?
Power on the CDR bus?
ANUN/NUM rheostat (panel 5) turned up (at least one 'notch')?

 

[grummanonewire]

Funny thing in the scn file after starting it the mission timer is activated as indicated by number 1 however the numeric displays for event timer helium and mission timer are dark

I am trying to attach the lm portion of the scn file in txt format if my minimal understanding of these files is correct that should give you the breaker and switch positions I had to strip a lot of the agc emem and mem addresses and this is only the LM portion of the scn file

 

[grummanonewire]

mission timer issue

I have a limited understanding of the scn file but am thinking it is activated however numerics are dark
that being said you should have my switch and breaker positions this is the LM only portion in text format

all breakers are in from the checklist rheos are full bright override switches on
numerics are dark to include ET and helium pressure gauges CW system is not activated yet

 

[meik84]

AC numerics lighting power missing, presumably.
INV 1 or 2 powered (INVERTER switch in 1 or 2 & EPS INV 1 (2) cb in)?
AC Bus B Bus Tie cbs in?
AC Bus B NUM LTG cb in?

 

[Sloppyphan]

just starting to play around some more

setting up mission timer in the before PDI dat +94 hours im at the LM activation point and cannot get the Mission timer to light up followed the checklist and I am still on lo volt taps

I had this issue in #10, and double checked the transfer power to LM in the CSM, for me it was I hadn't made sure to take the LM power switch to full reset vs just off. So I did reset again to make sure and back in LM power was up and I had timer panel on.

 

[grummanonewire]

Ok so I looked at the scn file it is starting as it indicates as 1

I do not have any numerics

I went from nassp 7.0 to build 1508 do I need to go back and rebuild from the beginning of the build page or is there a build specifically I need or ?

---------- Post added at 01:30 AM ---------- Previous post was at 01:24 AM ----------

it worked did not know you had to have a inverter selected I thought that was for the voltmeter

 

[meik84]

This are those little-bitties a full fledged system simulation comes with. You may thank indy (?) for all of them. But yes, it's quite counter-intuitive. One might think that those are LED- displays (which would be okay with DC power), but they aren't. They are electro-luminescent displays and need AC power. I have no idea why they used EL displays instead of LEDs. Maybe they didn't trust LEDs, as they were quite new at that time.