This article presents the results of an analysis of the yaw marks left by a car with nominal pressure in all tyres and with zero pressure in one rear tyre. The analysis is a continuation of research on the influence of reduced tyre pressure on car lateral dynamics in a passing manoeuvre, discussed at the XXII EVU Conference in Florence. Apart from the determination of vehicle critical speed on the basis of yaw mark curvature commonly used in road accident reconstruction, a new method is applied in the analysis. In this method the slip angle and longitudinal slip of the wheel can be determined on the basis of the geometry of the striations which are an integral element of yaw marks. The aim of the research was reached by performing bench and road tests. Next, the results of calculations done on the basis of yaw marks geometrical features are compared with the real values known from the measurements of car motion parameters.

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