I've modified a large apron with Afcad, but now when I taxi across it there are "hard and soft" spots. Taxi is smooth in one area, but as you move across the apron the plane starts bouncing around and the tires begin to kick up dirt, etc. I'm sure this has to do with a default hard surface area defined in some default .bgl that doesn't match the size and shape of my new apron, and I'd like to modify the area to encompass my entire apron, eliminating the "soft spots". Can this be done with XML compiled to .bgl with bglcomp somehow, or is it a scasm thing? Also, which of the default .bgls is it that contains these surface areas? This is FS9 BTW, and I'm working on an airport originally in NamwSceneryAP916140.bglThanks,Jim

Hello Jim,You are probably right and your problem is probably due to an apron that extends beyond the flatten.You may be able to fix this by drawing a new flatten that is at least as large as the apron, and for that matter, the entire new airport.There are a few programs for doing this for FS 9 - you can try either Ground2K4 or SBuilder. Both are in the Avsim library.Don't hesitate to ask if you have any questions.Best regards.Luis

Thank you for your reply, Luis. As it turns out I had the surface type set as "Unknown 2" in Afcad because I liked the resulting concrete texture. Changing it to "Concrete" cured the problem with the soft spots, but I still don't understand why some parts of it where hard and others soft with the "unknown 2" setting. Something to do with taxi links from what I can tell. I made an experimental concrete apron polygon with no taxi links and it was completely soft. I then added an invisible apron route diagonally across it connecting to nothing and the surface became hard.It just seems a bit quirky how FS handles concrete aprons. Modifying drawSurface="" in the XML seems to have no effect at all, and drawDetail="FALSE" makes the apron become partially transparent. Incidentally all of my mods to this airport fall within the default flatten area according to LWMViewer.Have a great day :) .Jim