If not already existing, you first create a new folder and name this "AI" in the main-folder "Microsoft Flight Simulator X" . Open this folder "AI" and create another folder and name this "Airplanes". Activate this Aircraft-folder with the FlusiFix-2006 or paste following line under [Main] in the fsx.cfg:
SimObjectPaths.6=ai\airplanes
If the number 6 is already busy, you increase this number in accordance with.