1. A method of locating an underwater location beacon, said method comprising of the steps of: providing a linear sensor array; providing a tow body containing signal conditioning and digital communication circuits operationally connected to the linear sensor array; moving the tow body and the linear sensor array in a direction of motion; orientating the linear sensor array orthogonal to the direction of motion; beamforming acoustic conical beams in a conical beam pattern from the linear sensor array onto a seafloor; detecting with the acoustic conical beams subsequent to said beamforming step, a time series of acoustic data channels from the underwater location beacon; converting with a frequency-wavenumber beamformer, the time series of acoustic data channels into spatial beams of an acoustic frequency spectra of frequencies; determining if a signal of the underwater location beacon is present from each spatial beam; calculating a likelihood function for a location of the underwater location beacon to represent an area of the seafloor from which the signal of the underwater location beacon is likely to have originated; accumulating a plurality of likelihood functions for the location of the underwater location beacon over the course of a search pattern; and producing a grid map for a location of the underwater location beacon based on the accumulated likelihood functions.