Baffles (submarine) - Background and Etymology

Background and Etymology

Since a sonar array is extremely sensitive to underwater sounds, it must be protected from the noise generated by machinery on the vessel on which the sonar is installed. Otherwise, its own noise would tend to drown out other sonar targets. To reduce noise, sound-attenuating material is placed between the sonar and the rest of the vessel. This makes the sonar much more effective, but causes a blind spot where this material is: as most hull-mounted sonars are located at the front of the vessel, the resulting blind spot is located directly behind the vessel.

The term baffles is likely derived from a lesser used definition of the word itself, that of "a partition that prevents interference between sound waves in a loudspeaker." In the instance of its usage in terminology pertaining to submarines, the definition can be expanded and slightly modified to, "an area behind the submarine that due to the cavitation and the wake left by the propulsion system impedes the ability for on-board sonar systems to accurately establish what, if anything, is behind the submarine."