collotty you are correct. The folder is called MHTG-TERRAIN. When this is activated, the FS crashes when I near the airport during the day. When I de-activate the MHTG-TERRAIN, the MHTG airport works fine during the day but it looks weird because some terrain is missing. Everything works fine when I fly at night. I did find some posts about certain "season files" missing and I was able to download MHTG-FS9-CRASH-FIX that contains 525 BMP/AGN files but I'm not sure where I'm suppose to place the folder or the files.