Accession Number : AD0375047

Title :   SURFACE SOUND CHANNEL BEARING ACCURACY MEASUREMENTS IN THE OCEAN,

Corporate Author : SCRIPPS INSTITUTION OF OCEANOGRAPHY SAN DIEGO CALIF MARINE PHYSICAL LAB

Personal Author(s) : Williams,R. B. ; Fisher,F. H. ; Cushing, P.

Report Date : 26 JAN 1966

Pagination or Media Count : 6

Abstract : Absolute underwater acoustic bearing accuracy measurements were made using 5.0-kHz, 2-ms pulses at ranges from 1.3 to 28 kyds using a visual reference. This work was done in conjunction with the USS FECHTELER (DD870), using the FECHTELER as a sound source and receiving the transmission on FLIP, mostly at a receiving depth of 100 feet. Propagation loss measurements were made as a function of range from 1 to 45 kyds on three successive days. Variations in the propagation loss as large as 25 db were observed. Even though large amplitude fluctuations of about 15 to 20 db were observed, the standard deviation of bearing errors was about 5.5 minutes. A 30-element thermistor chain on FLIP measured vertical thermal structure every 6 minutes for the 3 days of operation. (Author)

Descriptors :   (*UNDERWATER SOUND, PROPAGATION), HYDROPHONES, MEASUREMENT (U) DIRECTION FINDING, RELAXATION OSCILLATORS, CAPACITORS, MEMORY DEVICES, DESTROYERS, RANGE(DISTANCE), STATISTICAL ANALYSIS, ERRORS, THERMISTORS, BATHYTHERMOGRAPHS

Subject Categories : Acoustics

Distribution Statement : APPROVED FOR PUBLIC RELEASE