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Studies of rollover accidents have reported crash attributes such as the number of rolls, rollout distance, initial over-the-ground speed, average roll rate, average over-the-ground deceleration, magnitude of roof deformation, cumulative damage, time and post-crash headroom. While these more general attributes are related to the repeated vehicle-to-ground impacts during a rollover, it has been previously shown [1] that a specific ground impact during a rollover and its consequences can be studied in more detail by using its acceleration time history (crash pulse or impulse) and energy loss. These two quantities are particularly meaningful to use when studying impact mechanics, however, they are limited to circumstances where the data exists, which means real-world on-road crashes cannot be used directly. Acceleration and energy data have been collected and previously published for three Subaru Forester dolly rollover tests, and have been studied in more detail in this writing.

When two vehicles contact in a side swipe collision, if one of the vehicles has lug nuts that protrude outboard of the wheel, gouge marks may be left in the other vehicle's exterior. Hereafter the marked vehicle will be referred to as the car and the vehicle with the lug nuts will be called the truck. If the car is stationary, the marks will be in the form of a curtate trochoid and will reveal no information about the speed of the truck. If the car is not stationary, analysis of the shape of the traces left on the side of the car by the lug nuts of the rotating truck wheel can determine the velocity ratio of the car to that of the truck. If the speed of either vehicle is known or can be determined using other information or accident reconstruction techniques, lug nut mark analysis will enable determination of the other vehicle's speed.

The subject of whether roof deformation in and of itself causes occupant injury in rollover accidents has been emotionally, scientifically and legally contested for decades. Since the publication of the earliest scientific research on the issues of automobile roof strength and non-ejected passenger protection in rollover crashes, the two views have been generally diametrically opposed to one another, and the debate continues. In order to gain perspective on the subject, the question must be answered as to how effective past and current automotive vehicle roof structures, designed to meet current government and industry standards, have proven to be in protecting vehicle occupants during real-world accidents involving the rollover of the vehicle they occupy.