Invisible airport mesh causing aircraft to fall

All of the airports we have so far released have custom mesh. It’s been a long
journey trying to find different methods to integrate such custom mesh when
running into issues that stem from the way the default mesh has a N to S
integration, integrating a sheer drop seems impossible without the use of 3D
fake terrain. After running extensive tests, it seems that there is an
inherent issue with default photogrammetry causing aprons, taxiways and
runways to be bumpy, in some cases so much so, that it leads to the aircraft
on top of the terrain layer crashing. Switching the photogrammetry off offers
an instant fix, eliminating the photogrammetry via TIN exclusion polygons
seems to have very little to no effect, I have no idea why this is so poorly
implemented in the SDK toolset. In the image below for instance there is an
invisible terrain mesh layer that has contours that strongly deviate from the
actual visible terrain profile:

When taxiing the aircraft just
before this particular area at Alicante Airport, you can actually see the
wheels disappear slightly into the ground, then they rise above the ground, as
shown above, and shortly afterwards the aircraft falls, as if it had taxied
onto a ramp that abruptly ends with much lower terrain. With photogrammetry
set to OFF, there is no such issue and the custom terrain mesh is smooth in
the apron, taxiway and runway areas, just as we designed and built it. Could
someone at Asobo kindly look into this and shed some light on why this
invisible terrain is present, and ideally find a solution to eliminate this
particular issue?

You may need to try a huge TIN exclusion.

Hello @PILOTS_Development I am afraid we don’t have a solution for this at the
moment. The explanation is that terraforming is well suited when using regular
grid terrain geometry. But when switching to TIN, the topology is irregular as
the name suggests and changes from one LOD to the next so terraforming have a
different result on each LOD. That’s why you can have some holes between
chunks of geometry and mismatch between what’s visible and what’s used for
plane physics. When creating an “exclude TIN” polygon, this just flattens the
TIN but the geometry remains the same. Eventually, we would like this exclude
option to fall back to regular grid geometry, that would solve this
terraforming problem. But this is not an easy thing to do. In the meantime,
I’m afraid your only option is to keep a flat geometry where the problem
occurs. You can try to adjust your terraforming empirically to see when it
matches the TIN geometry the best but this will be time consuming without any
guarantee of success. Regards, Sylvain

The default LEAL has some problems. With photogrammetry:

Without photogrammetry:
There’s no sinking of SimObjects
(aircraft) without photogrammetry, but this large, grey, morphed object
exists. I’m guessing it is caused by the default mesh.