Why is it that the f/sec are less than a third what it is during day time ...?My frames are locked at 25 and during the day it pretty much stay at 25 but during the same settings / weather / aircraft at night, it falls to between 9 and 13.RegardsT

It's all the light sources.Allcott

Also, if you are running at "dusk" as compared against true "night" then you are running two sets of textures which will eat up your FPS.

Also, if you have a lot of AI traffic, each AI aircraft loads twice the textures since it has the light map texture. If you have a lot of AI aircraft make sure your light map textures are mip mapped and DXT3 and maybe change them from 1024x1024 to 512x512.Matt