Statistical Comparisons of Aircraft Flyover Noise Adjustment Procedures for Different Weather Conditions

摘要

Measured aircraft flyover noise spectra and effective perceived noise level (EPNL) values obtained under widely different weather conditions have been adjusted according to a proposed national standard recommended by Working Group Sl-57 of the American Standards Institute. The results were statis¬tically compared with the same measured spectra adjusted according to an alternate procedure presented in the Society of Automotive Engineers Aero¬space Recommended Practice 866A and with reference spectra and EPNL values obtained under almost ideal weather conditions (isothermal profile and no wind). Three different ways to represent the weather condition through which the sound propagated were also evaluated.