Aircraft Noise Emission Model Accounting for Aircraft Flight Parameters

Abstract

Today's aircraft noise calculation programs either use simple sound source descriptions with few input parameters or very sophisticated models with demanding input parameters. To fill the gap between these two approaches, a new model is proposed with the scope to find a reasonable comproise between its degree of detail and number of accessible flight parameters. By means of an extensive data exploration, the flight parameters with the strongest influence on the sound emission level were identified. These parameters were incorporated in two multiple linear regression models, one for airframe and one for engine sound sources. A new method allowed Fitting both source models to flyover measurements of the total aircraft. In total, models for ninteen combinations of aircraft and engine types were eastablished, which underlines the generality of the new source model for turbofan powered aircraft. Exemplary comparisons between measurements and model predictions for two aircraft types revealed, that the model is able to accurately reproduce directivity and spectra for diffrent fligth conditions.