I once found and recovered an 8 ft. long side scan sonar fish a professor had lost when I was in college. It was tee boned into a ledge on the third reef. It originally cost $1,000,000.00 and was developed for mine detection and identification. It operated at a relatively high frequency for improved resolution, had bottom following depth sounder, circuitry and automatic machine-flown wing, rudder/stabilizer assemblies to maintain proper beam focus. It was comprised of five compartments including a section with explosively deployed pingers for marking targets. Pretty advanced stuff for "analog" technology. Digital versions were only starting to come online a few years prior to my finding the fish. I had about 1/2 mile length of shoreline it was supposed to be off of. That and the story of how it was lost. I assumed it came up on a relative steep ledge the bottom following depth finder would miss and slammed home. With that info I was able to find and recover it with three tanks in part of a day on the third reef in 90 ft. of water. That sucker was HEAVY though, bent a davit at Lauderdale Marina pulling it out of the water where I had it suspended by plastic 55 gallon drums. As the prof didn't throw the analog control console after it, it made one hell of a paper weight!
I am surprised to have found a photo of the unit from
http://web.mit.edu/museum/exhibition...can-sonar.html It was surplus tech before I found it, hence its donation to the FAU Ocean Engineering Department. The writeup says it was a top secret device for 25 years prior to that time? The professor pulled up the wing and umbilical, I recovered the balance from the third reef.
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