Practical method of considering effects of terrain and building structures on sound propagation

This paper discusses practical methods of calculating adjustments for sound insertion loss due to terrain/building structures in airport noise modelling. The Japanese revised noise guideline “Environment Quality Standard for Aircraft Noise,” requires sound exposure evaluation of aircraft ground activities like taxiing and using APU. This paper first makes a brief review of technical aspects of developing airport noise modeling in Japan, secondly describes the way of considering aircraft ground operation noise, thirdly discusses practical ways of calculating adjustments for sound insertion loss due to terrain/building structures and excess ground attenuation, and finally it discusses future issues. It also refers to examination of the validity of such practical ways by applying numerical calculation as well as by measurement.