Abstract
In prediction of aircraft noise, it is very important to calculate the attenuation. Especially far from aircraft, it must be considered not only attenuation for the distance but also ground effect and atmospheric attenuation. In this paper, propagation characteristics of aircraft noise which were mesured around Osaka International Airport were studied. Consequently, exess attenuation under 30 degree of elevation angle except attenuation for the distance could be show by logaristic function. The tendency of horizontal attenuation was about the same as the results of experiments by Parkin et al. In comparison the mesured exess attenuation with the culculation method of ground effect by SAE (Society of Automotive Engeneers), it was found out that the correspondence are quite satisfactory. Then the exess attenuation can calculate easily by converting EPN dB of SAE 's calculation method into dB (A) and giving some collection.
