🧪 BASE Jump Drag & Terminal Velocity Physics

This simulator integrates real freefall drag physics frame by frame rather than playing back a scripted fall: drag force F = ½ρv²Cd·A is computed from the jumper's actual body-position drag area every step, gravity and drag fight it out, and velocity asymptotically approaches a genuine terminal velocity instead of being capped by a rule. You choose the exit altitude, pick a body position that trades fall speed for reaction time, and decide exactly when to pull the chute — the deployment ramps the drag area up sharply over about a second of canopy inflation, producing a real, physically-derived deceleration curve (including a brief, intense "opening shock") rather than an instant speed change. Live altitude-vs-time and velocity-vs-time charts track the whole flight, and the final impact velocity is compared against real parachute-landing-fall thresholds to judge whether the jump was actually survivable.