What is a Sonobuoy?
A sonobuoy is a device which is dropped into the ocean and used to gather acoustic data. There are a number of different types of sonobuoys, designed for a variety of applications from anti-submarine warfare to whale research. All sonobuoys are characterized by being very rugged, built to withstand severe weather and extreme temperature and pressure, and many are also designed to be essentially disposable, as loss of a sonobuoy is quite common. The sonobuoy owes its development to the Allied need to monitor submarine traffic in the First World War. With the development and deployment of the German U-Boat, the Allies realized that they would be powerless against the Germans unless they had a way to identify and track the German U-Boats. The result was the development of early sonar systems, which used sound waves in a variety of ways to identify objects moving through the ocean. Planes started dropping sonobuoys into the Atlantic to track the course of U-Boats, and ever since then, thes
A Sonobuoy is a cylindrical device, which was deployed (dropped) from a low-flying airplane. The buoy portion, which contained a two-way radio and antenna, would float vertically on the surface of the ocean. Depending upon the model, either mounted directly on the bottom of the buoy or hung at the end of a cable, there was a hydrophone (the sono portion, from the word “sonic”), a piezo-electric transducer which either passively or actively would listen acoustically for submarines. By placing several (at least three, usually five or six) Sonobuoys in a specific pattern, one could triangulate the position of the submarine. The two-way radio communication between the airplanes that deployed and then controlled and listened to the Sonobuoys employed “frequency hopping”. This frequency-hopping was implemented in analogue hardware. As such, it was too slow and had too few frequencies to provide much noise-immunity (reliability). It provided only slight immunity to interference among themselv
