Free Spirits Half-Pipe

A half-pipe (literally meaning "half pipe") is a ramp with a semicircular or paraboidal cross-section. It is used in sports such as skateboarding , freestyle BMX , and aggressive skating . A rider descends it in harmonic motion (damped by friction) until they lose height. The athlete can recover the energy dissipated by friction by pushing off, similar to the movement of a swing to gain speed.