Analysis of Measured Environmental Noise Levels: An Assessment of the Effects of Airbase Operational Model Variables on Predicted Noise Exposure Levels.

摘要

This report presents an exhaustive study of measured noise data collected over a three week period at McChord AFB. The NOISECHECK methodology for comparing noise predictions to measured noise data was used in an effort to quantify the complicating factors relevant to airbase environmental noise prediction. These factors are dominated by parameters of the aircraft operations model. The operational model parameters are segregated and their effects on noise level predictions discussed, using the Probability of Consistency as a measure of their overall impact. It was found that noise generation was very sensitive to relatively small changes in power setting. The operational model of aircraft altitude and track location produced the most significant effects on predicted noise levels. The level of detail analysis attained allowed further assessment of the problems of noise generation and propagation modeling. The detailed NOISECHECK Sound Exposure Level analysis was automated using a database management system, which greatly reduced the effort required to conduct the repeated analyses required for this study. The retrieval and comparison of NOISEMAP noise level predictions were also automated. An accurate approach to estimating the operational parameters needed to model variable aircraft operations was developed and partially validated.