Development of Car/Trailer Handling and Braking Standards. Volume I: Executive Summary

You are here: Homepage > Search

Development of Car/Trailer Handling and Braking Standards. Volume I: Executive Summary

R. H. Klein / H. T. Szostak

This report summarizes the development of handling and braking performance requirements for passenger cars towing trailers. These requirements are based on the results of over 2000 combination-vehicle tests with eight trailers and three rear wheel drive tow cars (in 95 different configurations), over 500 tests with three trailers and two front wheel drive tow cars (in 38 different configurations), plus the results of previous trailer towing research. The proposed standards include recommendations for straight line braking performance, trailer swing stability, tow car steady turn stability, and combined brake in turn stability and performance. For straight line braking, the recommended performance criterion is 0.4 g deceleration of the combination-vehicle. A tow car weight based on trailer brake capability requirement is presented to insure that the combination-vehicle will meet this deceleration requirement. For trailer swing stability the safety-related performance measure is damping ratio, or the equivalent cycles to one-half amplitude. A minimum damping ratio of 0.15 (or 3/4 cycles to one-half amplitude) has been recommended.