Accession Number : ADD006199

Title :   Very Low Frequency Sonobuoy (VLF Sonobuoy).

Descriptive Note : Patent,


Personal Author(s) : Stixrud,Thomas E

Report Date : 17 Jul 1979

Pagination or Media Count : 7

Abstract : An apparatus hydromechanically decouples a hydrophone arrangement disposed in a water medium from the effects of current, wind and surface wave action. A first float carrying a transmitter-antenna assembly extends through the water-air interface and is tethered to an auxiliary float which buoyantly supports the hydrophone arrangement, A line, hundreds or thousands of feet long, is suspended by the auxiliary float and terminates in a sonobuoy tube at a predetermined depth. From the tube the hydrophone arrangement and a high pressure float are pulled out by a weighted nose portion. After the hydrophone arrangement, high pressure float and a length of line are pulled from the tube, a weak link between the hydrophone arrangement and nose portion snaps allowing the weighted nose to sink. The high pressure float has sufficient buoyancy to support the hydrophone arrangement and a portion of the length of line causing it to assume a cantenary configuration. The combination of the tether, the entrained mass of the tube and the cantenary hydromechanically decouples the hydrophone arrangement from the effects of current, wind, and surface wave action acting on the other components of the sonobuoy. (Author)

Descriptors :   *Patents, *Sonobuoys, Very low frequency, Hydromechanics

Subject Categories : Acoustic Detection and Detectors
      Fluid Mechanics

Distribution Statement : APPROVED FOR PUBLIC RELEASE