Apollo 11: IVT into LM process questions

Wedge313

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Hello, I'm about 97 hours into the flight, trying to get Neil and Buzz situated in the LM. One issue I'm having is with the CO2 PP. As I complete the ECS Activation checklist, the reading on the CO2 gauge jumps immediately from zero to 8, and continues to quickly rise until it's pegged full scale. Switching to the secondary canister has no effect. I've run through this IVT process twice, with the same result, and I'm not sure where I'm going wrong. Something I missed earlier?

The other area I'm having trouble with is the LGC Clock Sync and TEPHEM Update. The checklist has me bouncing back and forth between the CM and LM, and I'm not clear how I'm supposed to sync up the two computers. I'm also not clear how to accomplish the TEPHEM Update. Am I done after I hit "ENT" on the PAMFD?

And what is (and what do I do for) "load dT"?

Besides the checklist on the MFD, is there another source that has these procedures laid out?

Thanks again.
 

indy91

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We do get the same effect as the real CSM and LM, but probably more accidentally than simulating something in a super realistic way. The CO2 from the astronauts accumulates in the LM over the course of the translunar coast, where it doesn't get scrubbed as the LM is unpowered. I think it tends to go to some manifold in the suit circuit. So once you activate the LM ECS (I think it's the step where you start the suit fans) the CO2 will be evenly spread over the suit loop, including where the CO2 sensor sits and is now being measured as very high.

With the LM ECS fully running this problem does go away after a while, although for a bit it's probably unsafe for the astronauts. A quite recent feature, and a bit experimental still, is on the ECS page of the PAMFD. There is now an option to install a hose connected to the CSM suit loop through the tunnel going into the LM, creating a slight overpressure and leading to much better air circulation. So that's a realistic solution to a realistic problem and it seems to work quite well in NASSP. But you would have to do it for many hours to have a real effect. With the suit fans running the CO2 scrubbers in the LM will also eventually do the job, just takes a bit.

The LM AOH Volume 2 has the procedure for the clock synchronization, "LGC/CMC Clock Synchronization Routine (R33)". Routine 33 it refers to is simply doing V06 N65 to show the AGC clock time.

For the TEPHEM, that is the precise liftoff time in triple precision, so three octal numbers. And you want to use this as the time reference for mission elapsed time in both CMC and LGC. So the procedure is to simply read out the numbers from the CMC and then input them in the LGC, so that they are the same in both computers. So the V05 N01E, 1706E just reads the numbers from the CMC. And the V25 N01E, 1706E is used to enter the three numbers into the LM DSKY. A V05 N01E, 1706E is then the check that the numbers were correctly entered into the LGC.

Clock sync is slightly more involved. As you can't be two astronauts at once in NASSP, pressing buttons on two separate DSKYs at the same time, we have a button in the PAMFD, LGC page, to do that. So you type in V06 N65 on both the DSKY in the CSM and LM. And the "ENT" button on the LGC page of the PAMFD is then pressing the ENTR key on both DSKYs at the same time for you, showing the clock time of both AGCs at the same time, too. What you would get there is e.g.

LM:
+00100
+00000
+00000

CSM:
+00100
+00000
+00012

So that would be 100:00:00.00 GET in the LGC, 100:00:00.12 GET in the CMC. A clock difference of 0.12 seconds. So you need to increase the clock time of the LGC by that same 0.12 seconds. And that is what Verb 55 is for. You would enter:

V55E
+00000E
+00000E
+00012E

To increase the clock by 0.12 seconds. And when you then repeat the V06 N65 procedure with the PAMFD ENTR press you can then see that you have the clocks synchronized.
 

rcflyinghokie

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Regarding the CO2, if you are ever running IVT, the astronauts should be on the CSM ECS or you need the CSM O2 hose connected. If you have either of these cases, the CO2 should not be an issue. I have run a few missions now and have yet to have CO2 issues as long as one of those conditions is met during any IVT or before connecting to LM ECS.
 

Wedge313

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OK, I'm obviously missing something, because I just killed Neil and Buzz for the third time. They're starting to get upset with me.

How do you hook up the CSM O2 hose? When I move both crewmen to the LM, the checklist has me remove them from the CM (leaving only one). Both CM and LM hatches are open. I then have two crewmen in the LM. As soon as I run the ECS Activation procedure the CO2 PP indicates 8, rises quickly to max, crew status goes critical. At this point I've got the CDR in his suit (PAMFD ECS), and the LMP in the cabin. But no hose connected to the CM. Its only a short time until both crewmen are dead.
 

rcflyinghokie

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The hose is in the PAMFD under ECS in the CM. Is this the first time you were in the LM? What about the housekeeping steps?

And how long was your crew in the LM cabin? In the LM suits without the suit fans on?
 

Wedge313

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The hose is in the PAMFD under ECS in the CM. Is this the first time you were in the LM? What about the housekeeping steps?

And how long was your crew in the LM cabin? In the LM suits without the suit fans on?

All good questions. No, it's not my first time in the LM, I've been following the flight plan so I've been in and out as scheduled. All I can guess is that I got back into the CM before the CO2 was an issue.

And I'm in the CM, looking at the PAMFD, opened to the ECS page. I don't see anything that would allow me to connect a hose. The only things I am able to control are the number of crewmen in the cabin (CRW tab) and the glycol loop test power (PRM and SEC tabs). The CDR, LMP, and EVA tabs do not have any function that I can see.

I do remember the first time the flight plan had me enter the LM, there was a step to hook up the hose and (I think) the power, but I couldn't find any way to accomplish that. So I (incorrectly) assumed it was sort of automatically done for me.

So I'm still at an impasse. I'm not seeing a way to hook up the hose. If I artificially leave all three crewmen in the CM, press on with the LM preparations, and then just before CM/LM separation put the two crewmen into the LM in suits, can I work around it that way?

FWIW I'm running NASSP V8.0 Beta 1616 that I installed in March 2021, and Orbiter 2016 Beta.

I know I messed up at some point. I'd like to get it corrected. But now I'm just hoping they drop the murder charge and change it to involuntary manslaughter.

Thanks.
 

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I believe the hose was added about 3 months ago, you're a few versions behind. Updating at this point may be tricky, though mid-mission, though, so I would avoid it if at all possible.
 

rcflyinghokie

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All good questions. No, it's not my first time in the LM, I've been following the flight plan so I've been in and out as scheduled. All I can guess is that I got back into the CM before the CO2 was an issue.

And I'm in the CM, looking at the PAMFD, opened to the ECS page. I don't see anything that would allow me to connect a hose. The only things I am able to control are the number of crewmen in the cabin (CRW tab) and the glycol loop test power (PRM and SEC tabs). The CDR, LMP, and EVA tabs do not have any function that I can see.

I do remember the first time the flight plan had me enter the LM, there was a step to hook up the hose and (I think) the power, but I couldn't find any way to accomplish that. So I (incorrectly) assumed it was sort of automatically done for me.

So I'm still at an impasse. I'm not seeing a way to hook up the hose. If I artificially leave all three crewmen in the CM, press on with the LM preparations, and then just before CM/LM separation put the two crewmen into the LM in suits, can I work around it that way?

FWIW I'm running NASSP V8.0 Beta 1616 that I installed in March 2021, and Orbiter 2016 Beta.

I know I messed up at some point. I'd like to get it corrected. But now I'm just hoping they drop the murder charge and change it to involuntary manslaughter.

Thanks.
As n7275 stated you are a missing a few ECS updates in your version. If you want, you can update NASSP and I can fix your scn file so it's compatible with the latest NASSP.
 

Wedge313

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OK thanks. I'm only marginally computer literate, but I've been able to slog through most Orbiter/NASSP stuff with the help of people like yourself. Let me know what I need to do first, get the latest NASSP version and install ? Or save a .scn file first? (Not Orbiter.log?)

Thanks
 

rcflyinghokie

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OK thanks. I'm only marginally computer literate, but I've been able to slog through most Orbiter/NASSP stuff with the help of people like yourself. Let me know what I need to do first, get the latest NASSP version and install ? Or save a .scn file first? (Not Orbiter.log?)

Thanks
So go ahead and attach the scn file you wish to resume from here and I can fix it to work properly with the ECS changes.

You can then just go ahead and install the latest NASSP version and I will attach a fixed scn file for you to use
 

Wedge313

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Here's a save at 96+00, about ten minutes before beginning the IVT. Let me know if you need anything else, like an earlier save.

Also I can't remember, do I have to remove/delete the older NASSP version before installing the newer one?

Thanks.
 

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n72.75

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Just install over the previous version. No need to remove anything.

@rcflyinghokie, dont forget about the SPS padload value, if you're updating.
 

Wedge313

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And if you want to beef up the RCS fuel, and throw in some cheeseburgers, the crew would appreciate it.
 

rcflyinghokie

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And if you want to beef up the RCS fuel, and throw in some cheeseburgers, the crew would appreciate it.
All set, got some extra consumables, made sure the CO2 was scrubbed, and even waxed Eagle for you ;)

Just remove the .txt extension to make it a .scn file and make sure you run it with the latest NASSP version.

Let me know if there are any issues as I wasn't able to check it personally, just made the edits!
 

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Wedge313

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Wow! That's quick service! And it's nearly impossible to get your vehicle detailed in lunar orbit, so thanks!

I'll get that all loaded up today, and let you know how it goes.

Thank you very much.
 

Wedge313

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OK! I'm up and running again. I turned what should have been an easy process into a more difficult one (I couldn't get the new NASSP version to work. After numerous attempts I went with the nuclear option, uninstalled and reinstalled everything). But your new fix seems to be working, no issues yet. The CO2 issue is gone. The crew is happy.

One self-induced problem after the reinstall: the exterior of the CM and LM is a monotone grey. I've messed up some textures somewhere. Any hints where I might start to fix this?

Thanks again for the help.
 

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OK! I'm up and running again. I turned what should have been an easy process into a more difficult one (I couldn't get the new NASSP version to work. After numerous attempts I went with the nuclear option, uninstalled and reinstalled everything). But your new fix seems to be working, no issues yet. The CO2 issue is gone. The crew is happy.

One self-induced problem after the reinstall: the exterior of the CM and LM is a monotone grey. I've messed up some textures somewhere. Any hints where I might start to fix this?

Thanks again for the help.
Do you have a side-by side 2016 and Beta R90 install that are sharing a textures folder. If so make sure that the NASSP textures get copied into your 2016 textures folder as well.

See the note after item 5 in https://www.orbiter-forum.com/threads/nassp-8-installation-guide.36801/
 
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