Evaluation of procedural changes for minimizing noise impact near military airfields

Abstract

Over time, communities surrounding military airfields tend to grow, while the noise generated by subsequent generations of military aircraft tends to increase. This creates an accelerating problem of human exposure to noise. One technique to alleviate this disparity is to modify attributes of flight trajectories in a way that reduces the sound exposure of the population. This involves the changing of flight ground tracks, profiles, and power settings within linear and non-linear boundaries which can include exceptions (such as no-fly-zones.) To demonstrate the effectiveness of these changes, DNL levels are calculated for real world population distributions and existing Navy departure procedures. These values are generated computationally using the widely accepted NoiseMap model. It is shown that significant reductions of exposure averaged over the population can be achieved in this way. Possible methods for automating this procedure are discussed. Properties of the objective function spaces are explored (e.g., convexity) and the appropriateness of different optimization methods is discussed. [Work supported by Naval Air Warfare Center.]