One of the inventors of Side Scan Sonar, German scientist, Dr. Julias Hagermann, who was brought to the US after World War II and worked at the US Navy Mine Defense Laboratory, Panama City, FL from 1947 until his death in 1964. His work is documented in US Patent 4,197,591, which was first disclosed in Aug 1958, but remained classified by the US Navy until it was finally issued in 1980.
Military side-scan sonars were made in the 1950s by Westinghouse. Advanced systems were later developed and built for special military purposes, such as to find H-Bombs lost at sea or to find a lost Russian submarine, at the Westinghouse facility in Annapolis up through the 1990s.