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Gemini 060615 released!
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1  Project Apollo - NASSP / Project Apollo - NASSP News & Discussion / Re: List verbs & nouns on: September 21, 2017, 09:17:58 PM
It's in the G&C checklist under word checklists too.
2  Project Apollo - NASSP / Support & Bugs / Re: CMC frozen on STBY / LVDC not achieving orbit on: August 29, 2017, 01:59:11 PM
I am a bit confused which scenarios you use with which NASSP version. Are you using the latest scenarios from the NASSP 8.0 Alpha releases with the Orbiter 2010 branch? Or did you try it with the NASSP 7.0 release version? The NASSP 7.0 release and the Orbiter 2010 branch are not the same thing.

Alright, here's the breakdown of what scenarios I'm using.

The scenarios packaged with NASSP 7.0 release version (master branch) works on the latest release on both NASSP 7.0 and NASSP 8.0

The scenarios packaged with NASSP 8.0 Alpha doesn't work on either version.

The scenarios that are not working are attached above. They are the 1st and 2nd files listed.
3  Project Apollo - NASSP / Support & Bugs / Re: CMC frozen on STBY / LVDC not achieving orbit on: August 28, 2017, 09:28:30 PM
Makes sense, I did notice how the FDAI wasn't exactly at 90 degrees pitch after P01.

As for the CMC issue, my saved scenarios seem to work fine, as all of them are at least at T-30min. It's the  T-4h scenarios that come with the latest NASSP release that have this issue. The old scenario, Apollo 7 Virtual AGC LVDC++ MCC - Launch.scn, has no such issue even when used on the newer release.
Is it safe to use the old scenario with the newer NASSP release, or have there been significant changes made to NASSP between the two releases such that I may encounter other issues down the road?
4  Project Apollo - NASSP / Support & Bugs / CMC frozen on STBY / LVDC not achieving orbit on: August 28, 2017, 01:11:00 PM
Hi guys, I've not flown NASSP for a couple of months now, decided to fly Apollo 7 all over again with the latest release.

I've encountered 2 different problems, one each on Orbiter 2010 and 2016.

On Orbiter 2010 (latest commit on Orbiter 2010 branch), the CMC shows a only a STBY light and becomes totally unresponsive after the light test on the startup checklist. It still shows STBY and nothing else with the CBs pulled. Same issue with Apollo 8.

On Orbiter 2016 (release 693), LVDC will not put the spacecraft into a stable orbit, it puts me into a 160-something by -70-something orbit. Not caused by propellant shortage, scenario editor confirms that there is propellant in the S-IVB after cutoff.
Apollo 8 LVDC works as intended, putting the spacecraft into a near circular 100-something orbit.

Scenarios used are,
Orbiter 2010:
Apollo 7/8 MCC - Launch (1st & 2nd attachments)

Orbiter 2016:
Apollo 7/8 MCC - Launch (3rd & 4th attachments)
Apollo 7 - 01 - Before Launch T-60s
Apollo 8 - 02 - Before Launch T-60s
5  Project Apollo - NASSP / Project Apollo - NASSP News & Discussion / Re: Apollo 8 vAGC TLI on: June 04, 2017, 12:47:31 AM
You don't need to do anything to setup TLI in the latest version of NASSP. TLI is handled by the LVDC, you just need to monitor the burn.
6  Project Apollo - NASSP / Project Apollo - NASSP News & Discussion / Re: Proper reentry procedure on: January 20, 2016, 11:33:36 PM
Wow, how could I not have noticed, thanks almostfm.

Just to prove how I did not proofread before posting, I meant 410.0 and 390.0 on the readout, thanks indy91 for pointing out that error
7  Project Apollo - NASSP / Project Apollo - NASSP News & Discussion / Re: Proper reentry procedure on: January 19, 2016, 11:31:54 PM

For example, if you're passing 4 on the scroll, but EMS reads 4100, you're undershooting by 100NM. If it reads 3900 you're undershooting by 100NM.

One of those (I'm guessing the one where the EMS says 3900) should mean you're overshooting by 100NMi.

The numerical readout is your current range to go, and the dashed line on the scroll is the range you should be at. So if the numerical readout is higher than the scroll, it's an overshoot, and vice versa.
8  Project Apollo - NASSP / Project Apollo - NASSP Development / Re: Virtual AGC on: January 16, 2016, 07:41:29 PM
Now I have another problem, 117h into the flight, the CMC doesn't seem to be able to receive uplinks from both RTCC MFD and PAMFD.

The first time I do a SV update with PAMFD, it shows 'connected' and the values to be uplinked, but nothing happens to the DSKY, stays at P00. Subsequent attempts to uplink via PAMFD shows 'failed to connect"

As always, scenario provided. (G&N powered down, but shouldn't affect uplink to AGC)
9  Project Apollo - NASSP / Project Apollo - NASSP News & Discussion / Re: Proper reentry procedure on: January 15, 2016, 09:55:15 PM
I agree with dseagrav, every space mission wasn't just about the astronauts, there was a large team of controllers on the ground as well. Think of the MFDs as mission control, having any information we need readily available through comms.

Now, for the procedure, typing out everything that you'll see when using the DSKY is too long and impractical, so you'll want to refer to this document: http://history.nasa.gov/alsj/a15/A15Delco.pdf
It's a AGC/LGC manual for Apollo 15, and it describes all programs that the CMC could run. Do take note that some of these programs weren't available on Apollo 8 due to a older 'software version'.
Everything you'll need though, is in that document.

What you'll need is:
P30 (external dV) and P40/P41 (SPS/RCS maneuver) for LOI, TEI and any midcourse corrections.
I'll assume you know how to use these 3 if you've gotten as far as reentry on Apollo 8.

P52 (IMU align) for realigning the FDAI to reference reentry attitude, you'll want to use option 2-Nominal for the align option, GET will be the time at entry interface.
P61 (reentry preparation) for the actual reentry, do take note that it advances automatically from P61 through to P67. Once you hit P63 though, there's nothing else to do on DSKY



P52 isn't critically important, unless pointing prograde or retrograde will put you roughly within 30 degrees of gimbal lock. Otherwise you can honestly just skip P52 and just use EMS for entry.

So, that just leaves P61 that you have to know how to use.
You'll want to run P61 with enough time to jettison the SM, reorient to the reentry attitude, and set up your EMS - 30mins before EI works.

As for the EMS,
Switch mode to 'EMS test' and scroll it to your inertial velocity at .05G.
Switch mode to 'RNG set' and set your range to splashdown.
Both of these can be gotten by hitting V16N63

Switch EMS mode to 'Entry' and activate EMS.
Finally, once you're in the proper orientation for entry,turn on 'EMS roll' and '.05G' on panel 1.


Now, you can sit back and relax, CMC is in control of the spacecraft. Of course, that's not what the astronauts would be doing during reentry, they would be monitoring the DSKY and EMS to ensure that the CMC wasn't going to burn the CM up, or skip out completely.

This is a EMS scroll you'll see

The numbers at the bottom represents velocity in kft/s.
From left to right, the lines curving down represents your maximum G buildup, you don't want your trace going down faster than the 'descending' line closest to your pointer or you risk burning up.
The lines curving up represents your minimum G to prevent skipout, you don't want your trace going up faster than the 'ascending' line closest to your pointer or you risk skipping out.
The vertical line at 25500kft/s represents orbital speed. Once past this speed, you cannot skip out.
The dashed lines with numbers represents the distance to go check lines, cross reference this with the numerical readout (which represents range in hundreds of NM) to determine over/undershoot at the landing site.
For example, if you're passing 4 on the scroll, but EMS reads 410.0, you're undershooting by 10NM. If it reads 390.0 you're overshooting by 10NM.

The pointer on the bottom left represents the CM lift vector. The lights on top and below of the pointer are the corridor verification indicators. Basically, when the light comes on (either top or bottom), the lift vector should be pointed towards the light.

In any case of:
Risk of burning up
Risk of skipping out
Lift vector pointed away from corridor verification light

Take manual control of the spacecraft (which is practically an aircraft at this point) and continue reentry manually. Using the distances check lines to aim the CM towards the landing spot.

EDIT: corrected EMS distance to go check. Thanks almostfm and indy91
10  Project Apollo - NASSP / Project Apollo - NASSP Development / Re: Virtual AGC on: January 10, 2016, 04:46:39 PM
I was on x20, I shall try re-running the scenario at x10. Thanks
11  Project Apollo - NASSP / Project Apollo - NASSP News & Discussion / Re: Proper reentry procedure on: January 10, 2016, 02:49:00 AM
You'll need to know a few things,
1) GET at entry interface
2) Lat/Lon of splashdown point
3) How to enter data on the DSKY
4) How to do an IMU alignment.

To know whether you're in the proper orientation for reentry, run a P52 (option 2) realign, enter your GET at EI on F06 34, and complete a normal realignment. The FDAI will now show LVLH orientation at EI. As long as your pitch is around 180deg, you will reenter heatshield first.

Now, to set the autopilot to do the reentry, run P61, on F06 61, enter your splashdown lat/lon on R1 and R2, R3 must be -00001 unless your entry angle is too shallow (shallow enough to risk skipping out).
PRO until you see F50 25 with 00041 on R1, it's now time jettison the SM.
After jettisoning the SM, ensure SC CONT is in CMC and it's on AUTO.
Hit PRO again, autopilot will now maneuver to the reentry attitude
PRO again.
Autopilot is now set for reentry. Just sit back and relax.

Now this is just an extremely simplified procedure for setting up the autopilot and how to get you on the ground. There are a lot of useful information on P61 through P67 that's used to monitor the reentry, I'd be happy to explain in further detail if you're interested.
12  Project Apollo - NASSP / Project Apollo - NASSP Development / Re: Virtual AGC on: January 09, 2016, 11:06:34 AM
Just getting back to NASSP after learning of many new updates to the sim.

I've got 1 issue so far, the DSKY seems to freeze up, I think PAMFD is able to uplink data to the AGC but there but DSKY just shows P00 with no UPLINK ACTY light.
The only way I can get the DSKY to work again is by pulling the circuit breakers for the computer on panel 5, and hard restarting the AGC.

Scenario attached
13  Project Apollo - NASSP / Project Apollo - NASSP Development / Re: Virtual AGC on: March 03, 2015, 10:03:48 AM
7G max is almost exactly the same as the actual Apollo 8 flight, just 0.2Gs more.
14  Project Apollo - NASSP / Project Apollo - NASSP Development / Re: Virtual AGC on: March 03, 2015, 06:34:13 AM
It continues to happen with the correct splashdown coordinates for Apollo 8. The only way I've gotten it to stay within 5-7G is by extending the range to splashdown such that CMC has to go into P65 and P66. Even deorbiting with P37 from LEO, the CMC will undershoot and overstress the CM on the way to it's own computed splashdown zone.

The initial phase of entry is pretty much nominal, CMC guides the CM until it's guidance converges, and stays on path until something makes V06N66 line 3 become +99999 , and rolls the CM to fly lift down. CMC continues to think a overshoot is going to occur until V16N67 shows that the spacecraft actually landed 70-200NM short of the splashdown zone.
15  Project Apollo - NASSP / Project Apollo - NASSP Development / Re: Virtual AGC on: March 02, 2015, 04:41:12 PM
Trace for EPO entry:


Trace for lunar entry:




Looking at the EPO trace, CMC decided to put the CM into a dive when it was already pulling 7G at the 18,000fps mark.
And the lunar trace starts off pretty much as expected until 24,000fps when it decided to dive.

Another thing I noticed is that the downrange error will always end up at +9999.9 (and it will do so suddenly) which is what I think is causing the CMC to command a dive, even though the reality is that it's landing short.

Do you maybe have a Apollo 8 scenario before reentry for me, so I can test some things? I haven't progressed that far with my Apollo 8 mission  Very Happy
Here you go
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