After the tragic loss of the submarine Thresher in 1963, NRL designed an unmanned, instrument package that was repeatedly towed over the area where the Thresher went down and produced a detailed photomontage showing all known pieces of the wreck. Subsequently, deep-ocean search capability became a major effort at NRL. A Deep Ocean Search System (DOSS) was developed and successfully used in more than 30 search missions between 1965 and 1974, and it located and photographed the lost submarines Scorpion, Alvin, and Eurydice.
In the early 1970s, NRL developed a deep-sea photographic system called LIght BEhind the Camera, or LIBEC. The position of the high-intensity lights in the LIBEC system significantly improved photographic coverage of the ocean bottom.