Empty folders in "Aircraft"

[Birdman]

Recently loaded CFS2 and have had some success in downloading other aircraft.  Neat stuff!  However, some downloads didn't work, so I looked thru the advice of others and found out about aliasing.  Good enough, I understand that.  What I don't get is why there are several aircraft folders that apparently came with the original program load that are empty regarding Aircraft, Sound, Panel, etc.. These are planes I would to out, but I'm just not sure how to get the right file (aliased?)into them.    ????????????

[SilverFox441]

The "empty" planes are the ones designed to be flown by the AI. You can convert them to flyable by downloading the conversion packs.

I can't seem to find them here at SimV (I'm sure they are around somewhere), but I know they are available at Netwings.