Sound Transmission Measurements in the Long Island-Bermuda Region, Summer, 1949
Abstract
Sound transmission measurements at 7.5 and 15.5 kc were made at 18 locations along a triangle between Long Island, Bermuda, and the Virginia Capes, using an underwater telephony transducer and a string of six hydrophones suspended at depths of approximately 15, 30, 50, 125, 250, 450 ft. from surface ships. Level measurements of a cw signal for various depth combinations and out to ranges of between 10 and 15 miles were plotted as transmission cross sections, showing an excess or deficiency of level at each range relative to a reference value assuming only spherical spreading and attenuation. The data indicate a deficiency of signal at short ranges, with a gradually increasing relative level beyond, until at extreme ranges the levels are in excess of expected values in homogeneous absorptive ocean. In one portion of the area an internal sound channel was found to affect sound transmission at 15.5 kc.
Document Details
- Document Type
- Technical Report
- Publication Date
- Jan 18, 1950
- Accession Number
- ADA800523
Entities
People
- R. J. Urick
Organizations
- United States Naval Research Laboratory