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AlexxV avatar image
AlexxV asked FNX_Dave edited

Aircraft ocassionally teleports to the underground


We have an issue with aircraft abruptly teleporting to below-ground level.

So far, we've validated that this happens even with no extensions on the affected machines. Also, this happens to other aircraft, not just ours (albeit with much lower frequency).

On top of that, I've validated that we're not setting the altitude ourselves via SimConnect.

See examples:

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AlexxV avatar image AlexxV commented ·
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FNX_Dave avatar image FNX_Dave commented ·

Just to add to this:

- It's not reliably repeatable in any scenario. Some machines seem to have it happen more frequently, but we couldn't find correlation (system specs etc).

- It doesn't seem scenery related as we couldn't find any correlation to specific approaches/airports having it happen more or less (shooting the same approach 30 times might only yeald this behaviour once).

- Even if slewed back onto the tarmac/air, the aircraft will simply continue to spin/flip in place as if the flight model is completely corrupt.

- This issue first cropped up around SU10 IIRC, not correlated with any particular update from our side, (we verified this by sending affected users various older builds of our A320 and there was no change in behaviour).

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FlyingRaccoon avatar image FlyingRaccoon ♦♦ commented ·
Hello @AlexxV @FNX_Dave

Hard to tell what's going wrong without a reliable way to reproduce the issue to investigate it.

What airplane should I test to have the maximum chance to reproduce the issue?
Does it happen with the clear skies weather preset enabled?


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FNX_Dave avatar image FNX_Dave FlyingRaccoon ♦♦ commented ·

Hey Sylvain,

Thank you very much for responding, indeed this is a tricky one which is why we've not reported it until doing as much testing on our end as possible, but we're very much at a dead end after several months.

Honestly it seems the best aircraft to reproduce the issue in order are the Fenix A320, followed by the A310, and very occasionally the PMDG 737. Indeed users have been able to reproduce it with clear skies. We have one user who can very reliably experience this issue (e.g. with 50% chance on approach), but users with similar/identical specs do not get it. To keep things clean we've had affected users remove/uninstall all other add-ons and test purely with vanilla MSFS + Fenix, and the result is the same.

If it's not something you can reproduce within a reasonable time, we'd really value it being shown to some of the engine techs to see if they've ever seen anything like this or have any ideas. We're a bit stumped at this point!

Thanks again,

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FlyingRaccoon avatar image FlyingRaccoon ♦♦ FNX_Dave commented ·
Hello @FNX_Dave,

Our best chance is to gather data and info from one of your user who has the issue reliably.
Any chance you could redirect the user who encounters the problem 50% of the time to this discussion?

The fact it happens with airliners during approach makes me think about issue with flaps or spoilers.
We would need to know if the user touches any specific input before it occurs.
Also, recording a video with DevMode aircraft debug panels enabled would probably be useful (Drag, Tracking, Weight, Sim Tuning)


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