MTS is definitely the greatest vehicle mod for Minecraft, and almost scratches the itch that MCHeli left behind. Its mechanics are modeled after real world vehicles, and it has the most realistic flight physics of any aircraft mod in MC. It has mechanics like flaps, trim, airspeed (stalling is possible), individual engine thrust (flat spins sort of possible), etc. My only gripe with the mod is that all of these features make for terrible performance. You need a relatively lightweight modpack environment for the heavy math calculations to function properly, otherwise any tps lag (especially during worldgen) will cause you to lose control of the plane as it over-corrects and inevitably crashes. Boats also tend to have buggy controls, and so only one addon pack even has them. It does force you to optimize the hell out of your pack to use it though, so I suppose that’s good?

There aren’t many addons which add functional military vehicles, and those that do tend to be buggy (gun projectiles hitting the vehicle’s bounding box, not working at all, etc). So it’s mainly civilian stuff for player transport.

MTS is otherwise an awesome mod.