Ghost’s Better Flight Controls

Per-aircraft profiles. Physics is now per helicopter in Mods/BetterHeliControls/Profiles/*.json one file each, with a VehicleClasses list, a Notes line, and a full FlightModel block. Three examples write themselves on first launch, tuned to real mass and rotor size:
MD500: light agile scout: high authority, low inertia, fast. Darts.
UH-60: heavy utility: low authority against high inertia, big lazy rotor. Lumbers with momentum.
Gyrocopter: light, twitchy, underpowered (the file also covers Bdub's old-style variant).
Any helicopter from any mod gets a profile by dropping in a file; anything without one falls back to the config default, so unknown helis still fly. The in-game Options → Flight feel sliders now edit the aircraft you last flew (the page shows which) and saving writes that profile's file, creating one if the machine didn't have it.
Three improvements to the physics system.
Weight & momentum: a real rotational-inertia integrator. Heavy airframes take longer to spin up to a rate and longer to stop. Surfaced as a Weight slider.
Translational lift: the aircraft gets light and wants to climb as you accelerate through walking pace, settles decelerating into a hover.
Ground effect: a lift cushion within a rotor-diameter of the terrain; easier low hover, softer landings.