SONIC BOOMS RESULTING FROM EXTREMELY LOW-ALTITUDE SUPERSONIC FLIGHT: MEASUREMENTS AND OBSERVATIONS ON HOUSES, LIVESTOCK AND PEOPLE

Abstract : Sonic booms generated by F-4C aircraft flying low-level terrain- following profiles during Joint Task Force II operations near Tonopah, Nevada, were recorded under and near the flight tracks, and responses of structures, animals, and people were observed. Recorded overpressures up to 144 psf were analyzed, correlated with available aircraft operations data, and compared with data from different aircraft flying similar profiles. Observations of structures, animals, and people were correlated with the measured overpressures. Results include acquisition of near-field recordings of overpressures generated by the F-4C, the finding that some window glass fragments were propelled a short distance rather than falling directly below the window, an instance in which the measured overpressure of a sonic boom 1 mile to the side of the track far exceeded the predicted value, the finding that livestock (undetermined prior exposure to acoustic stimuli in this situation) did not respond adversely to the sonic booms, confirmation that very intense sonic booms do not harm people directly and the reaffirmation that the selection of site locations for low- level supersonic training missions will continue to pose a problem.