Abstract: A decoupling ring provided on the front annular face of the nose shell of a craft, surrounding the sonar array. This ring decouples the vibration in the nose shell from the fluid path. The decoupling ring is constructed of one or more mass elements on one or more compliance elements. The individual compliance elements are preferably vibrationally speaking springs and the mass elements are preferably metal segments which form a mass-spring system. The dimensions and characteristics of the mass and compliance rings are chosen to have a fundamental resonant frequency well below the sonar frequency range of interest, thus acting as a low pass filter. When the vibrational energy has a frequency above the resonant frequency of the mass spring system, the vibrational energy is attenuated effectively. The low frequency resonance of the decoupling ring is obtained by using a large mass and a large compliance in the mass and compliance elements, respectively.

Abstract: An array plate for use in an underwater craft. The craft having an array of sonar elements which has a selected range of operating frequencies. The array plate having at least one layer of material in which the layer(s) of material are designed to have selected natural frequencies of vibration throughout the range of sonar operating frequencies. The natural frequencies resulting in standing waves having selected wavelengths that develop along the layer(s) of material. The sonar elements are mounted upon the layer(s) of material such that adjacent sonar elements are spaced apart a distance of one half the average wavelength of the standing waves.

Abstract: An electrical connector for connecting a DIP and a wiring harness comprising a socket, terminals and a cover. The DIP has two sets of tabs which project from opposite sides of an insulated block and which are folded over onto the top and bottom surfaces of the block respectively. The DIP is disposed in a longitudinal slot at one end of the socket which is between two rows of terminal cavities. A terminal in each cavity is attached to a lead of the wiring harness and has a flexible contact bow engaging one of the tabs of the DIP. The cover is mounted over the slotted end of the socket to retain the DIP.