HehProbably a dumb question butUsing Garys UK2000 100AI for eg. I get nice 21 fps anywhere around London but as soon as I look at the airport whammo down to 3-5 fps. Now it is the AI but why does this happen even from a fair distance/long distance away??; merely pointing aircraft towards the airport has this effect surely this must be something wrong in FS programming. Its a shame , of course smooth as silk with AI turned down or off. Does FS load the polygons for all the planes ?Sun

http://ftp.avsim.com/dcforum/DCForumID8/18209.html#0 . Yes, it trys to render the polygons for the aircraft. It may not be rendering the buildings until approx 10mi distance from the airport. If you can see the buildings, then it is rendering everything in that part of the world.