Helix

A helix is a section of coaster track that spirals continuously — like a screw thread — without inverting the riders. Unlike airtime hills or inversions, helices generate sustained lateral (sideways) G-forces that press riders into the outside of the turn. A descending helix converts potential energy to speed while generating lateral force; an ascending helix bleeds speed while maintaining lateral pressure.

Helices are commonly used near the end of a layout to spend the train's remaining kinetic energy while providing an exciting, sustained turning sensation rather than an abrupt stop. The underground finale of Nemesis at Alton Towers — a tight descending helix carved into a rocky pit — is one of Europe's most celebrated helix moments. Expedition GeForce at Holiday Park in Germany closes with a famous positively-G-loaded helix that pins riders firmly into their seats. A well-designed helix can be as exciting as an inversion despite involving no upside-down element whatsoever.