Recent MSFS CTD Issues Linked to SPAACARS - updated 10-10

Attention Pilots,

It appears that recent changes with MSFS and/or Simlink has resulted in CTD's when using our SPAACARS program and the necessary FSUIPC 7 program.

Our ACARS program has not undergone any changes for several years, and has been relatively stable across versions of simulators - including MSFS, so I'm thinking that some recent change to MSFS/Simlink is not playing well with our ACARS program.

If you are using MSFS and are having CTD issues, this is likely the cause.  Since I don't use other simulators, I can't be sure that this issue applies across all simulators.

Until I can resolve this issue you may wish to file your pireps manually if flying MSFS and experiencing CTD's.  I will advise when further information is available.

Sorry for any inconvenience this may cause.

John

Just wanted to give a little background on this.  I recently began to have my MSFS crash to desktop at random times - generally after flying for over an hour.  I had tried a number of recommendations to deal with this.  I had finally moved all files from my Community folder, deleted the rolling cache and deleted Nvidia Crate and IQue programs without improvement.

I finally noted that MSFS seemed to run okay without SPAACARs running, even with FSUIPC running.  This led me to believe that the problem was related to some change in MSFS that made SPAACARs incompatible with MSFS.  I did a successful flight this morning with it after deleting an old SPAD.Next program that was no longer up to date, but I don't believed this solved the problem.  Testing is a slow process because any changes I make must be followed up with several 2-3 hour flights to see if the sim will CTD.

Upon reading and sharing on the forums, it appears that others have issues even though they aren't using FSUIPC - and certainly not using SPAACARs.  There has been recent issues with releases of Simlink versions that cause CTD.  FSUIPC forums indicate that it might be related to too many calls to Simlink that overloads it and causes the sim to crash.  This might explain why the embedded Simlink program shows error as a MSFS module failure and not external programs - but it would be nice if it would show Simlink as the source of the failure.

I've lots of additional testing to do and checking FSUIPC logs when my next CTD happens to help diagnose the problem.  

It's entirely possible that the solution will eventually come from an update from MSFS and/or Simlink that will correct this problem, since there really was no changes made to SPAACARs that would explain this problem.  Since users who also are dealing with this issue and are not using FSUIPC, that again points to Simlink as a likely cause, since programs that don't use FSUIPC usually interact directly with Simlink rather than going through FSUIPC as SPAACARS does.

Anyway, if you're not having problems with SPAACARS, or rarely having issues with it, you should continue using it.  My goal was to not have you frustrated over not being able to fly and doing all kinds of things to your flight sim setup trying to correct a problem that I'm currently working on.

I will continue to fly with SPAACARS to do additional testing, and you can also unless you're having frequent CTD's.  At that point you can change to manual pirep entry through the pilots office and not start the SPAACARS program.  There is also a FSUIPC. ini addition you can make to stop its processing of AI Traffic.  This takes some of the load off of Simlink and might prevent or further delay a CTD until the problem is utimately resolved.

If you want to recover a CTD flight with SPAACARS, I recommend the following process:

1.  Start flight using flight state save option in FSUIPC 7 (premium version)
If sim crashes to Desktop SPAACARS will sound repeated beeping alarm indicating that it has been disconnected during flight.  In that case you should take the following steps to restore your flight:

1. Restart the simulator and choose "load from pc" option.  The default directory is where you'll find the saved FSUIPC flight files you set in the previous step.
2.  After the saved flt file is loaded, but BEFORE pushing the "fly now" button, you should shut down FSUIPC that likely auto started with the sim was started again.
3.  When you start the flight you'll have to quickly regain control of the aircraft as it will want to dive down because it starts with zero airspeed and in landed configuration.
4.  Once you have the aircraft flying again and on course, you can start FSUIPC by going to it's containing folder and clicking on the FSUIPC.exe to start the program without having it reinitiate a start of the simulator, as it's already running.
5.  SPAACARS should still be running and making that annoying noise, and it will stop making noise and reconnect when the FSUIPC is running again.  Don't shut down SPAACARS if the sim crashes or you cannot restart it mid-flight.
6.  Shortly after SPAACARS makes auto reconnect with FSUIPC it will likely give Aircraft Weight and Aircraft Fuel warnings.  You will need to correct this warnings as they pop up by changing the values in the fuel/payload to match the values shown in SPAACARS popup messages.  These don't need to be precise, but within a few hundred units of fuel lbs and/or payload weight shown on the error popup message.  When the values are corrected satisfactorily to SPAACARS, the message will disappear and stay gone when you hit the "ok" button on the pup up message.  Don't hit the "cancel" button as this will cancel the SPAACARS upload process but it allows you to close SPAACARS without dealing with the popup box getting in the way.

7. Once you've responded to any SPAACARS error messages by adjusting your payload/fuel values to that listed in the popup error, and the messages can be closed with the "ok" button without reappearing, then your system has been restored and you can resume flying normally with the flight data to continue recording via SPAACARs and it will upload at the end of your flight as if there was no mid-flight crash of your sim.

I understand this is a pain, but when flying Econ flights, this will be preferable than starting the flight all over again and risking another CTD likely at a similar point into the flight.

I'll keep you informed here of any additional information, workarounds or solutions as I come by it, and if you have questions or comments, feel free to post them.

Thanks,

John

Thanks Chili, it's good to know it still functions with XP. It's likely this is specific to MSFS2020. I won't consider making changes to SPAACARS until I can verify that a change is necessary to fix a compatibility issue and not a temporary bug with MSFS or Simlink.