A validation test for the Acoustic Footprint Mission Planning System

QinetiQ North America, Technology Solutions Group (QNA) and Wyle Laboratories have integrated two mature, proprietary technologies into a prototype Acoustic Footprint Mission Planning System. Wyle's Noise Model Simulation (NMSim) uses validated linear noise propagation routines in combination with ray‐tracing algorithms based on weather data provided by QNA's Precision Airdrop System (WindPADS) to predict the time history of spectral noise levels from a flying aircraft at any number of user‐defined receptor locations. Through interpolation over a ground‐based receptor grid, the impact of noise propagated through a stratified atmosphere may be quantified in terms of audibility at any point inside the acoustic footprint. Weather data for the NMSim ray‐tracing routines is extracted from the WindPADS three‐dimensional forecast of wind, pressure, temperature and humidity in the atmosphere as a function of time. The three‐dimensional field is the result of physical and dynamic assimilation of forecast and measured atmospheric data, with wind‐forcing by the underlying terrain. This paper describes the results of a validation test performed at Yuma Proving Ground, AZ. It is shown that the noise propagation model predictions agree satisfactorily with the measurements of a C‐130 cargo plane. [Work supported by Natick Soldier Center.]