NASSP 8.0 Apollo 7 first phasing maneuver

[bcbarnes]

I started with the Apollo 7 launch scenario (without the MCC). So far so good, but at approximately T+03:04:45 I get a radio message from CAPCOM about an upcoming phasing maneuver, followed by lots of information and numbers (shown at the bottom). Next, going through the 'phasing' checklist, I'm asked to set the EMS scroll to the dV from the information, and the DET also. Unfortunately, I have no clue what most of these numbers mean. Has anyone else gone through this successfully and if so, would you mind giving me details on what all this means and how to proceed?

Phasing maneuver
003 20 all balls
Noun 82 NA
1641 + 1224
00057
32538
Noun 48 NA
0 + 16
Roll
Pitch
Yaw
183
299
002
remarks sep heads down retro -x. Expect to be in proper attitude by 03:16:30

 

[indy91]

All these numbers are part of a Maneuver PAD(= Pre-Advisory Data). These were a set of sheets that the astronauts had onboard to write down important data, in this case a phasing maneuver to get away from the S-IVB. You will find that these numbers fit line by line (except for some of the noun numbers) in the form in the Apollo 7 Flight Plan, PDF page 24. What each item means can be found on the next pages. So your predicted apogee altitude is 164.1NM, Delta V of the maneuver is 5.7 ft/s, and so on.

Now, the radio messages you hear during Apollo 7 are based on the transcript. So Apollo 7 performed this 5.7 ft/s maneuver at 3:20:00 GET. The maneuver has the goal to get the CSM about 70NM ahead of the S-IVB 24 hours after the maneuver. In NASSP+Orbiter the orbital drag of the CSM and S-IVB aren't exactly right, so the 5.7 ft/s is way off what you need for this maneuver. And because you are not using the MCC scenario you have to calculate the maneuver DV yourself.

The tool for this is the RTCC MFD, which comes with NASSP. For this specific maneuver (1st phasing maneuver) we have some pretty good documentation. There is the RTCC MFD manual, which you can find under "Doc\Project Apollo - NASSP\Programmers Notes". This document has the phasing maneuver calculation as an example. Then there is a document for the RTCC MFD inputs for all Apollo 7 maneuvers under "Doc\Project Apollo - NASSP\Flightplans\Apollo 7". These two documents are a bit outdated if you are using the NASSP 8.0 Alpha version. In any case they are referencing the "Lambert" page of the MFD, which is in the category "Maneuver Targeting".

The calculated maneuver you are getting should be around 1.7 ft/s, so quite a bit different than the 5.7 ft/s during the actual mission. After this calculation is done you can also let the RTCC MFD display you the Maneuver PAD in a similar style as the one in the Apollo 7 flight plan. This can be done under "Pre-Advisory Data" -> "Maneuver PAD". You probably just have to press the CLC button there.

 

[bcbarnes]

That was quick! Thanks for the info - I'll give it a try later tonight.

 

[bcbarnes]

Well, I'm getting farther ... Using the RTCC and the maneuver pad, I get a dV of -2.0. I figure that's in the ballpark. The flight plan then takes me to checklist "P47 Thrust Monitor Program". All that seems to go fine until I get to step 15 (looking at the excel spreadsheet), where I "Set DET (counting up to TIG=0"). So does this mean that if I have 10 minutes to go, I should set the DET to 50 minutes (so it reaches zero in 10 minutes)?

the next problem is at step 19 where I enter V49E on the DSKY. Step 20 says the "OPR ERR Lt" should come on, but it does not. I continue anyway, and press RSET and then V25E (step 22). At this point, I'm supposed to enter the burn attitude information, but the DSKY isn't taking any of my inputs.

Any help, guide, step-by-step, etc. would be very much appreciated.

 

[indy91]

Well, I'm getting farther ... Using the RTCC and the maneuver pad, I get a dV of -2.0. I figure that's in the ballpark. The flight plan then takes me to checklist "P47 Thrust Monitor Program". All that seems to go fine until I get to step 15 (looking at the excel spreadsheet), where I "Set DET (counting up to TIG=0"). So does this mean that if I have 10 minutes to go, I should set the DET to 50 minutes (so it reaches zero in 10 minutes)?

Yep, and the timer will continue counting up when reaching 0. So it's a useful time reference relative to the time of ignition.

the next problem is at step 19 where I enter V49E on the DSKY. Step 20 says the "OPR ERR Lt" should come on, but it does not. I continue anyway, and press RSET and then V25E (step 22). At this point, I'm supposed to enter the burn attitude information, but the DSKY isn't taking any of my inputs.

Hmm, then the AGC didn't actually take your V49E input. Were you in P00 when you entered the V49E? Something must have prevented it from starting the V49 routine. The DSKY would show V06 N22 and some numbers in the three registers, but that probably didn't happen for you. Try a "V37E 00E" and then V49E again. Maybe that helps in some way.

The operator light should always come on with V49. That's actually a proper bug in the AGC software version flown on Apollo 8 (which we are also using for Apollo 7). It's even in the flown checklists and everything. The bug was fixed for Apollo 9.

One other thing, you seem to be using the Excel checklist files as reference. That folder should really be renamed, because those Excel files are meant to supply the Checklist MFD (also included in NASSP). So that MFD shows the same information as the Excel file, just in the simulation and more readable. As you probably haven't been using the Checklist MFD so far you have to click yourself through it to find your current mission state. But I guess it is also possible to just read the Excel file.

 

[bcbarnes]

Ok - I noticed that OP ERR was flashing going into the phasing maneuver checklist, so I did as you suggested and ran P00 first and that cleared things up. Was able to use V25 to enter the appropriate values and continue on with the scenario (I assume the values are in Roll, Pitch, Yaw order, with no decimal places?). The CSM didn't seem to change orientation much if at all. Is this triggered by the P47 or by the DET reaching zero, or something else? Anyway, did my -2.0fps thrust using standard orbiter keypad keys at DET=0, and I'm movng on.

>>you seem to be using the Excel checklist files as reference.

Actually, no. I've been using the checklist MFD exclusively up until I decided to write the previous post (the FLASH option is my friend). Only once I decided to post the problem did I go looking for the Excel spreadsheet so that I could reference it and the step numbers in the post. Seemed more precise than trying to explain what step I was on.

Once again thanks, and also a "well done" to you and any of the other NASSP developers. An incredible piece of work.

 

[indy91]

Ok - I noticed that OP ERR was flashing going into the phasing maneuver checklist, so I did as you suggested and ran P00 first and that cleared things up. Was able to use V25 to enter the appropriate values and continue on with the scenario (I assume the values are in Roll, Pitch, Yaw order, with no decimal places?).

Noun 22, where you enter the desired IMU attitude, is in 0.01°. So if it says +18000 then that would be 180.00°.

The CSM didn't seem to change orientation much if at all. Is this triggered by the P47 or by the DET reaching zero, or something else? Anyway, did my -2.0fps thrust using standard orbiter keypad keys at DET=0, and I'm movng on.

Hmm, the attitude change is not triggered by P47 or the DET. That's all V49 in your case. After you have entered the last angle in the V06 N22 display you have to press PRO once and then get to the 50 18 display, "request maneuver to attitude". It should display the same angles there again. At that point you have to make sure the SC CONT switch is in CMC and the CMC Mode switch is in AUTO. Then press PRO and the display should change to 06 18 until the CSM reaches the desired attitude. At that point it switch to the flashing V50 N18 again. Here an extended Verb 49 checklist: https://history.nasa.gov/afj/ap15fj/csmgc/1-26.gif It's possible that you were in the right attitude by chance, but I am not so sure.

>>you seem to be using the Excel checklist files as reference.

Actually, no. I've been using the checklist MFD exclusively up until I decided to write the previous post (the FLASH option is my friend). Only once I decided to post the problem did I go looking for the Excel spreadsheet so that I could reference it and the step numbers in the post. Seemed more precise than trying to explain what step I was on.

Ah yes, that makes sense.

Once again thanks, and also a "well done" to you and any of the other NASSP developers. An incredible piece of work.

Thanks a lot. :thumbup:

 

[bcbarnes]

Now we're flyin' ! The GIF for V49 helped to solidify some of what you said. I was able to joyously watch the FDAIs slowly move toward the requested attitude. And from the external view - "The view is tremendous" I think quotes a number of astronauts - during the 06 18.

Anything I can ever do to help, just holler

Brian

 

[n72.75]

Sorry if this is a bit of a necropost, but this is the thread that came up when I searched, and a have a followup question to the questions asked here, even if they are from 2 years ago.

RTCC MFD says

XXX001 R
XXX204 P
XXX358 Y

What are the keystrokes to actually enter these angles?

I know the angles in R1-R3 are in XXX.XX°, so does XXX001 = 000.01°?

I think I'm missing something:facepalm:

 

[jalexb88]

Sorry if this is a bit of a necropost, but this is the thread that came up when I searched, and a have a followup question to the questions asked here, even if they are from 2 years ago.

RTCC MFD says

XXX001 R
XXX204 P
XXX358 Y

What are the keystrokes to actually enter these angles?

I know the angles in R1-R3 are in XXX.XX°, so does XXX001 = 000.01°?

I think I'm missing something:facepalm:

That would be R 001.00 P 204.00 Y 358.00

 

[n72.75]

That would be R 001.00 P 204.00 Y 358.00

:hmm:

It all works up until I hit the '8' in "35800". I get an OP-ERR and can't enter the digit.

For some reason it doesn't seem to like 8s or 9s. It's not showing these in octal is it?

EDIT.

Never mind, I'm 98% sure I'm doing something wrong.

 

[n72.75]

Well, I'm still sure I'm doing something wrong, but I'm not sure what it is.

V49E

This gives me a flashing V06 N22

Which should be
V06 = decimal display
N22 = ICDU angles (XXX.XX°)

So I hit V25E to enter the RPY angles into R1-R3

And it really seems like it only wants octal input

What am I doing wrong?

 

[jalexb88]

Well, I'm still sure I'm doing something wrong, but I'm not sure what it is.

V49E

This gives me a flashing V06 N22

Which should be
V06 = decimal display
N22 = ICDU angles (XXX.XX°)

So I hit V25E to enter the RPY angles into R1-R3

And it really seems like it only wants octal input

What am I doing wrong?

Maybe you are forgetting the + before entering the angles? (+000.00)

 

[n72.75]

:facepalm:

Well I've just lost all my street cred' here...

 

[indy91]

We have all done it at some point.

 

[rwitham]

Hello,

First and foremost, I would like to give hearty congratulations to all the developers on this project! Your work is outstanding! I played around with NASSP about 12+ years ago and I am ASTONISHED at the improvements. Well done! As a fellow software developer, I can imagine the effort that has been put forth over the years. :tiphat::thumbup:

I do apologize if this is considered a "necropost," but I was on the fence about posting here or creating a new thread which could be considered a "duplicate." So maybe I can't win.

My immediate questions concern the first phasing maneuver on Apollo 7. I am using the MCC scenario and struggling to understand what I need to do vs "mission control" to determine burn attitude, dV, etc. My understanding from this thread:
http://https://www.orbiter-forum.com/showthread.php?t=41006
that burns are calculated and can be uplinked to the spacecraft. Is that true? If so how? I have been able to access the MCC menu, but the uplink menu item only seems to be for state vector updates.

If burns are not calculated/uplinked "automatically" and instead the RTCC MFD is needed, can they be uplinked from there? I've looked through the RTCC MFD document but wasn't able to discover how.

My basic struggle is to how to make the MCC and/or RTCC interact with the spacecraft.

Again, you all have made a great achievement!

Thank you

 

[rcflyinghokie]

Burns are computed as well as appropriate to the mission. At the appropriate times in the mission target loads will be ready for uplink along with SV or REFSMMAT updates.

Some maneuvers you will need to enter the PAD data into V48 & P30, but it all depends on the mission.

 

[n72.75]

Ideally, MCC will just give you the PAD data for the burn. You should just be able to enter the V49 maneuver attitude and burn the required DV (something like 2ish ft/sec). I can't remember if this is working for Apollo 7 right now, but if it's not We'll be circling back to it shortly.

The RTCCmfd method is what I used using flight plan data. If I wasn't out of town I'd make a video.

 

[Joey190]

Hi all!

First of all thanks for this amazing add-on, it really challenges me in my free time I have now due to the pandemic (I´m a pilot so not so much work atm..)!

I still can´t get the Apollo CSM to do this phasing maneuver, after all these tips and checklists. The error needles are doing it´s thing after putting all the angles in like you did (in my case +18300, +20300, +00200), but the craft is not going to this attitude automatically. What did I forget? I added a photo of my panel state just after pressing the second PRO after loading the values.

I´m starting from the Apollo 7 scenario - 4 Before phasing maneuver T+3h10m

https://imgur.com/a/9zSqVvp

 

[MrFickles]

Maybe the DAP wasn't started up?

Try going to P00 and entering V46. You shouldn't see anything happen when you do, but try going to your burn attitude after that with either V49 or P41.