Air-time

In the context of amusement rides, air-time refers to the time during which riders of a roller coaster or other ride experience either weightlessness or negative G-forces. With roller coasters, air-time is usually achieved when the train travels over a hill at speed. Hypercoasters, such as Magnum XL-200 at Cedar Point, Behemoth at Canada's Wonderland, Bizarro at Six Flags New England, and Goliath at Six Flags Over Georgia, along with many wooden roller coasters, such as Balder at Liseberg, The Voyage at Holiday World, El Toro at Six Flags Great Adventure are rides known for having a particularly high total air-time.

Air-time is a result of the effects of the inertia of the train and the riders: as the train goes over a hill transitioning from an ascent into a descent guided by the rails, the inertia of the relatively loosely-attached riders causes them to momentarily continue upwards, resulting in the riders being lifted out of their seats. The duration of air-time on a particular hill is dependent on the velocity of the train, gravity, and the radius of the track's transition from ascent to descent. Zero-G (where the net vertical G-force is 0) is achieved when the downward acceleration is equal to that of gravity; where the downward acceleration is greater, negative Gs arise.

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