Efficient monitoring of aircraft noise near a military operating area

Abstract

Efficient monitoring of aircraft noise near a military operating area requires: (a) adoption of A‐weighted sound exposure level as the physical measure first to be applied to any noise event; (b) instrument design goals aimed exactly at the primary physical measure; (c) detailed knowledge of extreme time patterns such as sonic booms (frequency characteristics); (d) performance specifications for monitoring instruments, including tests for compliance, to ensure measurement within appropriate limits of A‐weighted sound exposure level of aircraft noise characterized by extreme time patterns; (e) the procedure to apply to a succession of sound exposure levels to form 1‐h average (A‐weighted) sound level as the short‐term summary, and to form yearly average day‐night average sound level, for example, as a long‐term summary; (f) tests to determine the psychoacoustic validity of time‐average sound levels, both short term and long term. As an example of detailed knowledge about an extreme time pattern, this paper reports sound exposure spectrum level from 0.5 to 2000 Hz for a 100‐ms sonic boom caused by fighter aircraft on Luke Air Force Range in Arizona. The C‐weighted and A‐weighted sound exposure levels of this and four other sonic booms measured in the same hour are utilized for illustrative calculation of A‐weighted and C‐weighted day‐night average sound levels near a military operating area.