So let me get this straight.  This is extreme, but let's say the only airport in the world you like is Heathrow, so you want to replace every other airport so that the only airport you can ever fly to is Heathrow, regardless of where in the world you fly?

I can't see why that would be impossible.  I just don't know how to do it.

If you're talking about taking a 'copy' of say the default Heathrow and 'pasting' it over say the default KLAX, that's impossible. For starters, the key buildings and objects in all the feature airports are area delimited. eg you can't put the Pyramids in Moscow and you can't put KSFO in Edinburgh Scotland.

But in any case there's no way to do it.

You can't even take a 3rd party airport (eg my Kai Tak) and install it in Edinburgh. You could if I 'built' it in Edinburgh and gave you the files but no quality designer is gonna waste their time doing that! You might want to try de-compiling all the scenery bgls, changing the lats and longs, recompiling etc etc etc but surely you've got better things to do with your life

So if you don't like an airport you've either got to find a ready-made replacement or make one yourself.

Sorreeee

BTW

AFCAD import airport allows you to load an AFCAD file that someone else has made and incorporate its contents into your scenery.

Exporting is making a file that you can give to other people to import....

Only possible with Version 1 because it deals with txt files that modify scenery files. Version 2 works differently because FS9 is different.