The physics of airtime
Negative G when the track falls away faster than gravity pulls you down.
Airtime is not “zero gravity” magic. The train follows a downward curve; if that path accelerates downward faster than free fall at that moment, the seat cannot keep up — you lift against the restraint.
Floater airtime is mild negative G — gentle separation. Ejector airtime is sharper — the restraint catches you quickly after a peak.
Shape matters more than height alone: a small, well-shaped bump at high speed can out-eject a tall, rounded hill.
Upstop wheels on steel coasters prevent the train from leaving the track when guests lighten the load.
Related guides
Airtime hills explained
Shaped hills that pull you out of the seat — the heart of hyper and many modern layouts.
Gravity on roller coasters
The train is always falling — track shape decides which direction that pull becomes force on your body.
G-forces on coasters (basics)
Positive, negative, and lateral — three directions of force that define ride feel.