I never ever fly any of the default planes and I would like to remove them from the plane selection list. Can I simply remove all the appropriate folders from P3D's Airplanes folder...? Or will this cause havoc? I only fly one (or two A2A planes). If this isn't a wise thing to do, how else can I get rid of all the unwanted planes?

LOL Never mind... I just discovered the option to only show favorites, which is an option that sticks! Nice. Problem solved.

An easy and safe way to remove them while retaining the folder structure just in case any other aircraft needs something from within is to just rename each aircraft.cfg  to aircraft.cfg.OLD or something and then delete the original. The aircraft will stay in your sim intact but NEVER be seen from your vehicle selection screen.

Brilliant!  Re-naming the aircraft.cfg works like a charm. Good tip Dave.

Jd 

Just delete them (copy them to another location for backup)

I do this since years

I believe you can also just rename the panel folder. Without panel folder, it is considered only for AI and is still available for such, if used by something else. You don't see it in the list.

Of course things might have changed.