Transmission Loss of Low Frequency Underwater Sound in the Cayman Trough (CHURCH GABBRO Technical Note)

Abstract

Underwater acoustic propagation loss measurements made in the Cayman Trough as part of the CHURCH GABBRO exercise of Nov-Dec 1972 are reported. 1106 Mk 82-0 SUS set for 91.4 meters were dropped from shipboard and 302 SUS Mk 61-0 set for 18.3 meters and 176 SUS Mk 82-0 set for 91.4 meters were dropped from aircraft. CW projectors were also employed but only the SUS runs proceeded from ENE to WSW along the strike of the Trough; aircraft runs followed a four segment pattern including passages along Trough axis in WSW and ENE directions. One ACODAC receiving system was located in the approximate center of the Trough, about 140 miles WNW of Montego Bay and a second ACODAC system was located in the SW end of the Trough, a distance of some 355 miles from the first. Each ACODAC deployed six hydrophones throughout the water column, extending from the channel axis to critical depth (and below in one case). ACODACs recorded for a period of 10.6 days, of which SUS runs encompassed about 3 days. TABS and SONOBUOY receiving systems were located about midway between ACODACs during aircraft SUS runs. These systems sampled a total of four shallow depths from 18.3 to 396 meters. Data were reduced by Woods Hole Oceanographic Institution, Applied Research Laboratory of the University of Texas at Austin and the Naval Underwater Systems Center, New London Laboratory. Data reduction systems are described.

Open PDF

Document Details

Document Type
Technical Report
Publication Date
Jun 01, 1974
Accession Number
ADC000424

Entities

People

  • Scott C. Daubin

Organizations

  • Rosenstiel School of Marine, Atmospheric, and Earth Science

Tags

Communities of Interest

  • Air Platforms
  • C4I
  • Energy and Power Technologies
  • Materials and Manufacturing Processes
  • Sensors

DTIC Thesaurus Topics

  • Acoustic Measurement
  • Acoustic Propagation
  • Acoustics
  • Aircrafts
  • Ambient Noise
  • Charts
  • Computations
  • Computer Programs
  • Computers
  • Convergence Zones (Sonar)
  • Data Processing
  • Data Reduction
  • Detection
  • Detectors
  • Explosives
  • Transmission Loss
  • Underwater Sound

Fields of Study

  • Environmental science

Readers

  • Acoustics.
  • Coastal Oceanography
  • Radio communications and signal processing.