The Shipboard Degaussing System
When a ship is close to a magnetic mine or magnetic torpedo, the
magnetic field of the ship actuates the firing mechanism and causes the
mine or torpedo to explode. Degaussing is an electrical installation
designed to protect ships against magnetic mines and torpedoes. The
purpose of degaussing is to counteract the ships magnetic field and
establish a condition such that the magnetic field near the ship is, as
nearly as possible, just the same as if the ship were not there.
Shipboard degaussing installation consists of permanently installed
degaussing coils, a control unit to control the coil current, and compass
compensating equipment to prevent disturbances to the magnetic
compasses by the magnetic field of the degaussing coils. Figure 2-9
illustrates the types of coils that are found on a typical degaussing
Figure 2-9. Typical degaussing coil layout.