Reconstruction of road accidents are increasingly being used in courts. Some accidents involve a vehicle skidding over an embankment. This paper derives approximate analytical expressions for the launch phase of such an accident. These, together with the equations for free fall, are then used to calculate the initial speed of the vehicle. The analysis assumes that the vehicle does not ground on the edge of the embankment. A simple test on the initial speed is developed to ensure that this assumption is not violated. Some numerical results are presented to illustrate the differences between this analysis and two other models. Extensions to the analysis are suggested.
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