Here's a trick I stumbled across by accident. I'll use my 747 as an example of editing the aircraft.cfg file.
If you just want ATC to call you something else change
(flightsim.0) ...
atc_airline=Global (or whatever it is right now), to
atc_airline=Lufthansa (or whatever you want ATC to call it)
If you want to dump the default textures, and I have only tried this with replacements to default textures, download a Lufthansa 747 which is designed as a replacement and put it in the 747_400\texture folder. Make sure that:
title=Boeing 747-400
Just to be safe I would back up the \texture folder AND the aircraft.cfg file.
If you want to add another one (mine is Swissair) do the same thing for /texture.1 and further edit aircraft.cfg to read:
(flightsim.1) ...
title=Boeing 747-400 Paint1 ...
atc_airline=Swissair
It is very important that the "title" section not be disturbed - it must say Paint 1, Paint 2, etc. - because that's where FS looks for the AI information. And you have to make sure that atc_airline is one of the supported ATC airlines. There is a list here
http://www.fsgateway.com/tips_read.asp?id=411That's how to turn the default aircraft into AI aircraft with real liveries. There is another program to create other AI's and flight plans but I don't use it. I'm sure someone will come along and tell you about it.