Apollo 9 MCC Bug?

Max-Q

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In flying Apollo 9 at GET 119h 40m I expect a maneuver PAD for SPS-6. I get the familiar "Thread started" message... then nothing. No "Thread Completed", no PAD, no uplink, nothing. If I exit the simulator and reload, I get the missing "Thread Completed" message and an empty PAD (all zeros!) I tried the MCC debug option "Reset SubState" or whatever that option is, but no luck. All the other MCC stuff has been working fine so far, is there a way to calculate my SPS-6 PAD in RTCC so I can keep going with my mission and bypass this bug?
Scenario attached.
 

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rcflyinghokie

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In flying Apollo 9 at GET 119h 40m I expect a maneuver PAD for SPS-6. I get the familiar "Thread started" message... then nothing. No "Thread Completed", no PAD, no uplink, nothing. If I exit the simulator and reload, I get the missing "Thread Completed" message and an empty PAD (all zeros!) I tried the MCC debug option "Reset SubState" or whatever that option is, but no luck. All the other MCC stuff has been working fine so far, is there a way to calculate my SPS-6 PAD in RTCC so I can keep going with my mission and bypass this bug?
Scenario attached.
Looks like a hung computation, I will let @indy91 take a look and see what happened.

I would hold off on pressing on until he can take a look just to be sure later computations aren't impacted.
 

indy91

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Ok the problem is that the SPS-6 maneuver tries to get you into a 95x130 NM orbit, but the maneuver point happens at an altitude of 131.7 NM. That obviously doesn't work. Might be the reduced drag that we have right now that caused you to still be in an orbit with an apogee of above 130 NM. I thought I had prevented this from causing an unrecoverable error in the MCC, but apparently not.

In reality there would be an error message to the flight controller and he would just correct the desired apogee to 132 NM or so and then it will calculate right. I'll try to find a good way to accomplish this, shouldn't take too long!
 

indy91

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The latest NASSP release should have a fix for this bug. When you load the scenario from above the SPS-6 calculation will now give a good Maneuver PAD. I solved the problem by adjusting the desired apogee height if the height at TIG is above that. So as I said, in your case the calculation wanted a 95 NM perigee and 130 NM apogee, but the time of ignition happens at 131.7 NM altitude. Instead of a failed calculation like before this now results in a 131.7 NM apogee. So the burn becomes entirely retrograde, with just a tiny DVZ component.
 
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