Tire blow-outs and motorway accidents

During the period from 1996 to 2002, 60,397 vehicles were involved in crashes with property damage and/or injury on a French motorway network of 2000 km. It was observed that 6.7% of these accidents involved tire blow-outs. In 87% of cases, only one vehicle was involved in the accident. Tire blow-outs occurred in 6.5% of cars that represented more than 80% of the vehicles involved in crashes. The occurrence of this phenomenon is very high for vans (22%), though it concerns trucks less (2.5%). The proportion of tire blow-outs decreased from 1997, when it was 8.0%, to 5.9% in 2002. However, two main facts require examination: (1) On inter-urban motorways, crashes involving blow-outs of rear tires occur four times more frequently than for blow-outs of front tires. (2) The frequency of tire blow-outs is especially high for vans, and almost always involves rear tires. This higher frequency for rear tires is the result of two phenomena, which are indistinguishable given the data available: firstly, a four-wheel vehicle is more difficult to control if a blow-out occurs on a rear tire (confirmed experimentally); secondly, rear tires may be in poor condition more often than front tires, and so more prone to blow-outs. Consequently, users are strongly recommended to install the best tires on rear wheels. In practice, if only the front tires are replaced, which often occurs because they tend to be worn out more quickly than the rear ones (especially for front wheel drive vehicles), it is necessary to move the rear tires to the front and fit the new ones on the rear wheels. Very interesting technological developments are in progress that should reduce the number of tire blow-outs. However, considering the time necessary to renew the number of cars on the roads, this very simple and inexpensive recommendation should apply to all cars and especially to vans.