I only use add-on commercial flights for my simming. PMDG 747 and 737 on VATSIM.Therefore all my default FS9 aircraft are redundant to my needs. Would it be safe/sensible/dangerous/unwise if I DELETED these unused aircraft files?Many thanksIan Oak-Rhind

I don't think it would cause any problems to remove them (but I may be wrong). There might be an issue when the "default of defaults" Cessna is missing. Why not move them to a non-FS directory and test... I've never tried removing the default aircraft but as a general rule, add-ons etc that I'm not using are stored outside of the FS disk to keep things slick.GeoffPS. With the default planes you can delete (since you have them in the FS9 CD) but anything else you have taken the time to download is worth compressing and storing someplace... just in case you need it again! Disks and storage are cheap these days after all!

I've removed my defaults except for the cessena as it is required when FS9 loads up. It's perfectly safe although some addon aircraft does use default planes for the panel or sound so make sure those point to something else, otherwise it shouldn't be a problem

You can even do without Cessna, just appoint any other addon to be your default (make default button when saving).The folder you shouldn't delete:defaultfsfsconvtemplatesBasically, all non-aircraft folders should persist.

Many thanks for both helpful responses.....I have done the deed but kept the three vital files as recommended....FS9 still seems to work okay.Onwards and upwards.....Ian