Uncertainty analysis for parametric aircraft system noise prediction

Abstract

Parametric noise assessment in the context of low-noise aircraft design and flight procedure optimization has been around for more than 15 years. Continuous improvement of the models and the interconnection to other simulation tools, such as aircraft design codes, allow today's models to capture the major noise sources and relevant interactions along arbitrary simulated flights. Modem simulation processes even enable a fully automated aircraft design with integrated noise prediction capabilities. In contrast, reliable and comprehensive uncertainty analysis of the overall aircraft noise prediction process has not been available for parametric tools in the past. This paper will present ongoing DLR activities to assess the Overall uncertainty of its in-hause simulation process. The goal of the presented analysis is to define a general approach to specify uncertainties on the ground noise levels as predicted by a parametric system noise prediction tool, i.e. PANAM. This approach will allow to discuss the temporal and the spacial distribution of the uncertainties. Certain areas along a flight path are afflicted with different uncertainties than others. The impact on exposure-response relationships due to the variation in uncertainty will be discussed, i.e. the influence of varying noise source dominance along the simulated flights. Initial results of uncertainties along typical flight procedures and their Impact on selected metrics are presented in this contribution.