An early use of underwater acoustic positioning systems , credited with initiating the modern day development of these systems , involved the loss of the American nuclear submarine USS '' Thresher '' on 10 April 1963 in a water depth of 2560m . An acoustic short baseline ( SBL ) positioning system was installed on the oceanographic vessel USNS '' Mizar '' . This system was used to guide the bathyscaphe Trieste 1 to the wreck site . Yet , the state of the technology was still so poor that out of ten search dives by Trieste 1 , visual contact was only made once with the wreckage . Acoustic positioning was again used in 1966 , to aid in the search and subsequent recovery of a nuclear bomb lost during the crash of a B-52 bomber at sea off the coast of Spain
during the crash of a B-52 bomber
1966 Palomares B-52 crash
Underwater acoustic positioning system