this: a type of vehicle accident

Dynamics

Excessive cornering rollovers occur when cornering forces destabilize the vehicle. As a vehicle rounds a corner, three forces act on it: tire forces, inertial effects, and gravity. The cornering forces from the tire push the vehicle towards the center of the curve. This force acts at ground level. The force of inertia acts horizontally through the vehicle's center of mass in the direction opposite to the one it is turning. These two forces make the vehicle roll towards the outside of the curve. The force of the vehicle's weight acts downward through the center of mass in the opposite direction. When the tire and inertial forces are enough to overcome the force of gravity, the vehicle starts to turn over. Most passenger vehicles will slide or spin before this happens, but this is a common type of rollover for taller vehicles, including light trucks (SUVs, vans and pickup trucks), busses and heavy trucks.

Tripping rollovers occur when a vehicle is sliding sideways, and the tires strike a curb, dig into soft ground, suddenly regain traction, or a similar event occurs that results in a sudden lateral force. The physics are similar to cornering rollovers.

A collision with another vehicle or object can cause a rollover. These occur when the collision causes the vehicle to become unstable, such as when a narrow object causes one side of the vehicle to accelerate upwards, but not the other, causing the vehicle to rotate along its long axis. A side impact can accelerate a vehicle sideways. The tires resist the change, and the coupled forces rotate the vehicle. In 1983, crash tests showed that light trucks were prone to rolling over aftet colliding with certain early designs of guide rail.

A rollover can also occur as a vehicle crosses a ditch or slope rather than a flat road surface. Slopes that are steeper than one unit vertically for every three units horizontally are termed 'critical slopes' and often contribute to rollovers.

Competition

A skilled driver may stop the fall by stopping the turn. Stunt drivers in competition deliberately use ramps to launch a car, often a short, stubby subcompact which is more easily turned over. Short of a rollover, stunt drivers may also drive the car on two wheels for some time, but this requires precise planning, control and specialized safety equipment.

Rollover contest

The driver deliberately drives their vehicle to a ramp which causes their vehicle roll over. The winner is the driver who guides their vehicle to the most rolls.

Cars and trucks