We are the largest producers of sonobuoys in the world, with combined deliveries of over 10 million sonobuoys worldwide. ERAPSCO is your source for U.S. specification qualified sonobuoys.

During the Cold War, passive detection in deep water was the strategy of choice to covertly track nuclear submarines around the world. Since former Soviet Union and NATO relations have changed, detection needs have fluctuated. An increase in the number of diesel electric submarines under the flag of third world nations has led to an increase in the interest in active sonobuoys and shallow water detection techniques. ERAPSCO offers a full line of sonobuoys and technical support to address modern Anti-Submarine Warfare (ASW).

A sonobuoy is a device used to detect and identify objects moving in the water. Typically, a sonobuoy is used to detect submarines by either listening for the sounds produced by propellers and machinery (passive detection) or by bouncing a sonar "ping" off the surface of the submarine (active detection). Multi-static techniques are also used for submarine detection and localization. Multi-static operations utilize separate active source and passive receiver sonobuoys. Sonobuoys are generally dropped from aircraft that are equipped with a means to launch them, and electronic equipment to receive and process data sent by the sonobuoy, although they can be deployed from virtually any sea platform.

Sonobuoys are classified by size (A, B, C, etc.) and type (active, passive or measurement). All U.S.-manufactured sonobuoys, except the MK-84, are A-size (approximately 4 7/8 inch diameter X 36 inch length).

Sonobuoys with different characteristics other than those described can be designed and built to customer requirements, following a careful analysis of needs. ERAPSCO has designed and manufactured many sonobuoy variations over the years. Specialized sonobuoys can also detect electric fields and magnetic anomalies, as well as measuring environmental parameters like water temperature versus depth, air temperature, and barometric pressure.


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Sparton Corporation

Ultra Electronics

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