Crumple Zone

Crumple zones, crush or crash zones, are a structural safety feature used in automobiles, mainly in passenger cars, to increase the time over which a change in velocity (and consequently, momentum) occurs from the impact during a collision by controlled deformation; in recent years also incorporated into trains and rail cars.

Crumple zones are designed to increase the time over which the total force from the change in momentum is applied to an occupant, as the average force applied to the occupants is inversely related to the time over which it is applied.

Crumple zones are located in the front part of the vehicle, in order to absorb the impact of a head-on collision, though they may be found on other parts of the vehicle as well. According to a “British Motor Insurance Repair Research Centre” study of where on the vehicle impact damage occurs 65% were front impacts, 25% rear impacts, 5% left side, and 5% right side. Some racing cars use aluminium, composite or carbon fiber honeycomb, or energy absorbing foam to form an impact attenuator that dissipates crash energy using a much smaller volume and lower weight than road car crumple zones. Impact attenuators have also been introduced on highway maintenance vehicles in some countries.