There would be several types of suspension (Christie, Springleaf, etc.) that could be changed much like the wheels in game are, with a similar thing done for track type. You could determine the size via a slide wheel, again like the in game wheels.
Tank Tracks: How a random guy on this site thinks they should work.
8,448 aerodummy
6.3 years ago
Another Random Guy would like to have varios engine types(tank engines because you are forced to use two for differential steering)
Another random guy on this site thinks that before we have TANK tracks in SimplePLANES, we should have better aircraft AI, more diverse world, a built in multiplayer, a Linux build, and more aircraft parts
A random guy on this site also things that custom suspension is better than built in wheel suspention