Roller Coaster Loop Design: Why Oval Shapes Beat Perfect Circles

Roller coaster loops are not perfect circles because of the interplay of gravity, inertia, and centrifugal force. In a circular loop, centrifugal force would spike dangerously at the top, risking derailment and excessive G-forces on riders. An oval (clothoid) shape reduces the radius at the bottom and increases it at the top, balancing forces so the train maintains constant pressure on the track throughout the loop. This design ensures safety and a smoother, more enjoyable ride.