If you are using FS9 models like the AI Aardvark MD-80s, their ground shadows will not show due to the custom runway lights or something like that. Don't remember the exact reason why but it's something like that.
No, it's not like that. If FS9 models are used as AI in FSX, the WHOLE model (not just the shadow) will not display, UNLESS the "Airplane Cast Shadows on Ground" option is turned off.
But this is only valid for sceneries that use custom runway textures + default runway lights using a specific command that dates FS8. This is NOT the case at KDFW, which uses fully custom runway lights, so it's not affected by this. Only older sceneries are, and require to turn Airplane shadows off, in order to see FS9 AI.
So no, this is not the case. Since the user airplane shadows shows correctly, a possible explanation is those AI have their contact point a bit too buried in the ground (more than the user airplane), which is enough to have the shadows being covered by the ground texture.
Nothing to fix in the scenery, of course, which must use such kind of ground textures (*slightly* raised from ground), in order to offer native FSX materials with the associated fps benefit and full DX10/DX11 compatibility that comes with it.
