I can see some aircraft folders in FS2004aircraft that don appear in the selection menu. What are they and how can I use them?
These are the AI planes and they aren’t really intended to be flown, but there are various fixes which get around this. Try searching for the file ai.zip, which makes some of them flyable, or dh-8fly3.zip, which makes all three Dash-8s flyable. You will need to find panels to use with the planes, though.