The results of a field test to determine the directional characteristics of acoustic waves propagated through a jungle from overflying aircraft are presented. In general, when aircraft are directly over the test site, the sound at a point 20 ft. above the ground arriving from the direction of the ground measures about 6 dB lower than sound arriving from overhead. As the aircraft becomes further from the test site, the difference becomes less. (Author)
Acoustics Tests in Puerto Rico
1968
23 pages
Report
No indication
English
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