Study of noise production during car and motorcycle speed and cross-country races

Abstract The aim of this study was to investigate the real distance required to eliminate the noise inconvenience to local residents caused by cross-country and speed races by motorcycles and racing cars. Measurements have been made around nine motorcycle cross-country circuits, and a study of noise produced during the Belgian Formula I Grand Prix has been carried out at Terlaemen-Zolder. In addition, a few measurements have been made during cross-country car races and motorcycle speed races. The measurements yield useful data concerning minimum distances, effects of wind directions, growth, ground damping, screening by houses, unevenness of the terrain and other variables.