Sonic boom environmental impact prediction methods and issues

Abstract

Concerns over the environmental impact of sonic booms include their effect on humans, other animals, and fabricated structures. Over the past few years, CAA has been involved in a number of projects focusing on the latter two concerns. Specifically, working with Hubbs Sea World to supplement previous empirical studies, an analytical model was developed for estimating the sonic boom induced response of fertilized tern eggs and evaluated the potential for damage. Working with Wyle Laboratories, Inc., both direct and reciprocal structural-acoustic testing techniques were developed for simulating structural responses in order to assess damage. These methods were validated by comparison with data from actual flyovers. Curently, with Marine Acoustics, Inc., the authors are involved in a project to assess testing and other issues associated with predicting the subsea penetration of sonic booms for assessing marine mammal impacts. Here at issue are those physical processes that may transform from second to first order in light of the evanescent attenuation of the typically subsonic, ‘‘primary’’ acoustic wave that penetrates to depth. These three projects are reviewed in this talk. Particular attention is given to idealizations in the prediction process, the associated uncertainties, and their effects on the overall impact evaluation process. [Work supported by The Armstrong Laboratory of The U.S. Air Force.]