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Three methods of determining roll stability were examined for 27 vehicle configurations. The first method used parametrics to calculate a static roll threshold based on a simple planer model. This method is often used as a first approximation for rollover threshold due to its general ease of calculation. The second method used a tilt-table to determine roll threshold. This method accommodates suspension and tire deflections but not dynamic influences. The third method looked at dynamic roll stability under a steered input. This method does not attain the maximum dynamic roll threshold but does provide a means to compare vehicle roll stability.

Braking deceleration values in units of gravity on ice surfaces have typically applied to the locked and sliding wheel with a representative friction coefficient of 0.10 ascribed. Three years of testing winter roads for traction and braking capacities and controlled tests on an ice arena show that large percentage variations exist in friction values. The term ‘ice surface’ and its attributes is not well defined in the literature. Tests were run using different tires, at different temperatures, with and without ABS on smooth and rough ice surfaces and tabulated to show the differences in braking deceleration. The locked wheel values were compared with those values normally used by accident reconstructionists and indicate that care must be taken in selecting a representative value.