AIRCRAFT SOUND EXPOSURE, DIRECTIVITY AND PROPAGATION

摘要

At Oslo airport Gardermoen, more than 65000 measurements of single operations has beenrnmade, to verify that calculations systematically underpredict measured sound exposure on anrnaverage by approximately 3 dB. Preliminary analysis showed that both aircraft type and aircraftrnoperation were significant parameters.rnFor the time being, only indications can be extracted from the data. These indications tell us thatrnthe excess ground attenuation is one of the reasons, and probably the most important, why calculationsrnare underpredicting sound exposure. Another important factor may be the noise sourcerndirectivity.rnA measurement program carried out last summer will reveal more details on this item. Timernsynchronized data from third octave sound measurements in 5 different positions, together withrnradar plots and flight recorder data, will be the basis for an extensive analysis. The primary goalrnis to find the most important reasons for underpredictions, and how to mend it.