Ridge VFD firefighters gathered last evening for a special training class on the use of side scan sonar for underwater search & rescue. The class, taught by Assistant Chief John Keister, was specific to the new sonar we purchased, the JW Fishers Mfg., Inc. Portable SSS-600K Side Scan Sonar.

Side scan sonar is one of the most effective tools for underwater exploration because it can search a large area quickly and produce a detailed picture of anything on the bottom, regardless of water clarity. Applications for the 600K include: searches for drowning victims, sunken vessels, scattered debris fields, and a variety of other targets. It can locate targets of various sizes, from fish to sunken vessels, at ranges of up to 250 feet. Side scan sonar shows objects on the bottom and floating in the water.

The tow fish provides a stable platform for the sonar acoustic transducers. The power and signal pass through the Kevlar reinforced tow cable. The sonar processor provides an interface between the tow fish and the computer. Signal is sent from the tow fish to the sonar processor, which amplifies and conditions the signal before sending them to the computer for viewing.

Due to the number of members participating, Asst Chief Keister allowed for the use of his personal charter boat for the on-water portion of the drill. We searched for known underwater landmarks to demonstrate how to deploy and use the sonar, and how to accurately tune the signal to find the objects. Our primary targets consisted of a simulated drowning victim (training mannequin) and a sunken boat. We were also able to detect schools of fish and numerous on-water item (buoys, crab pot markers, retrieval lines, etc.).

The goal is to deploy this sonar capability, as necessary, during our water search and rescue calls. In the unfortunate event of a drowning or submerged vessel, the Ridge VFD will now be more capable to provide fast and reliable search assistance.