A
tilting train is a train that has a mechanism enabling increased speed on regular
rail tracks. As a train (or other vehicle) rounds a curve at speed, objects inside the train experience
inertia. This can cause packages to slide about or seated passengers to feel squashed by the outboard armrest due to its
centripetal force, and
standing passengers to lose their balance. Tilting trains are designed to counteract this discomfort. In a curve to the left, the train tilts to the left to compensate for the g-force push to the right, and vice versa. The train may be constructed such that
inertial forces cause the tilting (
passive tilt), or it may have a computer-controlled power mechanism (
active tilt).