Hi All - Great news, the change to the .....smokeC130.fx file in the FSX 'effects' folder as shown in the link you gave me above, does solve the problem. No more C130s 'on fire' after dusk in my night skies !
Thanks for your help.

Thanks for quick reply and link.
I assume the relevant bit is "open the effect file with an editor and under [Particle.2] change "Face=1,1,1" to "Face=0,0,1". I haven't tested it yet though. Let us know if it works"

Unfortunately there was no reply to this to say if it did work, so I will give it ...

Hi all - Using the RAF Mildenhall v2 in FSX, the AI C130s smoke trail is ok flying during day light hours, but from dusk into night hour flying, the smoke trail becomes a very large white light trail.
I assume this is only a problem in FSX. Any one else had this problem and know how to sort it ...