Addon airports and terrain mesh

[Dave81]

Hello, I recently dowloaded some freeware terrain mesh from simaviation.com. When flying into FSdream team KORD I had an issue when landing. Using the PMDG MD-11 the airplane suddenly went from 40 feet to the ground in an instant. I realize this is probably an issue with the mesh because this has not happened before I downloaded it, however I was wondering where does the mesh go in terms of priority in the scenery library? Does it go below all airport addons or above. I also have ultimate terrain and the mesh is below that. I think I read somewhere that terrain mesh can cause issues with elevations at airports but I am not sure if there is a way to fix it. This is also for FS9. Thanks for any help
Dave

[JamesChams]

Mr. Dave "Dave81,"

You should always put addons in this priority order (unless otherwise stated by the developer or some conflicts occur between addons):

1. Addon Airports PAYWARE.
2. Addon Airports FREEWARE.
3. Regional Terrain mesh PAYWARE.
4. Regional Terrain mesh FREEWARE.
5. AI Traffic or AI Static sceneries, etc.
6. Global/Terrain Mesh Addons PAYWARE or FREEWARE (eg. FSGlobal, FSScene, or UT, etc.).
7. FS Default Scenery items.

This setup usually (almost always) keeps everything "Happy" together; but, there are some exceptions (like AES which always wants to be on top).  Others may have more suggestions or differing opinions about certain products and you are also welcome to try theirs as well.

Hope this helps.

[Dave81]

Thanks James, that helped me out a lot.
Dave

[virtuali]

What James told you is generally correct, with one exception: MESH

Mesh scenery do not respect the normal layering order in the Scenery Library. Instead, the most detailed mesh will always shown, regardless of its order in the library.

The problems around the airports are quite typical for 3rd party meshes, because the Flight sim engine doesn't really support elevation changes over an airport property so, the airport has to be flattened at the official published altitude. This might create a problem with such a large area, like KORD when it connects to a 3rd party mesh that hasn't been processed to take this into account.

The default mesh from Microsoft has been smoothed out all around the airports so, problems like this don't happen. I hear that some of the latest commericial meshes has added this pre-processing as well, but it might not be present in the freeware mesh you are using.

Note that, this would happen exactly the same if you had only the default KORD installed. Basically, an addon mesh that hasn't been smoothed out to match with an airport, will create such problems at every airport. Of course, it's more noticeable with the largest ones, because the chance of an elevation change are higher over a larger area.

I hear that the upcoming FS Global 2010 will come with a tool that will allow users to fix the issue themselves at specific airports.

However, the general rule that an airport should be always placed on top of larger coverage areas, it's usually good to follow. That's why our installer will put the scenery on top of everything else.

[JamesChams]

Thanks James, that helped me out a lot.
Dave

Mr. Dave "Dave81,"
Your very welcome! Glad to be of help to you.


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...Mesh scenery do not respect the normal layering order in the Scenery Library. Instead, the most detailed mesh will always shown, regardless of its order in the library.
... because the Flight sim engine doesn't really support elevation changes over an airport property so, the airport has to be flattened at the official published altitude.
...The default mesh from Microsoft has been smoothed out all around the airports so, problems like this don't happen. I hear that some of the latest commericial meshes has added this pre-processing as well, but it might not be present in the freeware mesh you are using.
...I hear that the upcoming FS Global 2010 will come with a tool that will allow users to fix the issue themselves at specific airports.

Grazie, Virtuali!

I learn't something new here, in this discussion, too.  I'm getting the FSGlobal 2010 as part of a previous version (2005/2008) customer discount offer.  So, would we (users) have to know something about your airport's elevation or Microsoft's elevation data to smooth out the area around FSDT's payware airports?  Or, is this pre-processing done automatically with this tool (perhaps the way you do yours)?

Also, how does this apply to airports that are NOT flat?  Like this...

"Altiport Courchevel" for FSX


Ciao!

[virtuali]

Also, how does this apply to airports that are NOT flat? 

That airport is more like a very high res mesh shaped like the actual ground, with a texture that mimics a runway so, it's a trick to overcome the fact that an airport in FS9 or FSX can't be sloped. It works for very small and specific airfields, were it's acceptable to lose certain features, like AI traffic compatibility, but it's more like a special case, rather than something that can be generally used in all places, to simulated sloped runways, which the FS engine doesn't really support.