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Crash Events

Sequence of Events - Non-Collision Attributes:
Ran-off-road - used if the driver loses control of the vehicle and leaves the roadway.
Jackknife - applies to a condition that occurs to an articulated vehicle (any vehicle with a trailing unit(s) connected by a "hitch"; while in motion. The condition reflects a loss of control of the vehicle by the driver in which the trailer(s) yaws from its normal straight-line path behind the power unit.
Overturn - is used when a vehicle rotates 90o or more, side-to-side or end-to-end.  Also may be referred to as a “Rollover”.  An Overturn or Rollover should be treated as a single event when a vehicle performs multiple rotations in a crash.
Downhill Run-Away- refers to a vehicle that loses control due to brake failure on a downhill grade.
Cargo Loss or Shift - refers specifically to the loss or shift of items carried on or in a motor vehicle or its trailing unit, and not to the vehicle or trailing unit, itself. As an event in the sequence for this vehicle, the loss or shift does not have to be harmful. For example, tractor trailer rounds a sharp curve, causing cargo in its trailer to shift precipitating an overturn.