Free Flight, Free Speech

FGMEMBERS is an organization on Github that holds hundreds of aircraft. You as a FlightGear user can pick the planes you want, download them and fly them for free. FGMEMBERS is an independent projects and not subject to any restrictions or censoring by the FG core development. Aircraft in FGMEMBERS are GPL licensed (according to their authors) and can therefore distributed and expanded freely and without any limitations (means, you can send them to friends, give them a new color, extra engines or whatever fancies your imagination under the rules of the GPL license).
For aircraft distributed under different licenses, take a look at the FGMEMBERS-NONGPL forum.