Mines, Naval

a combat weapon (type of naval ammunition) for destroying enemy ships and making their maneuver more difficult. The principal characteristics of naval mines are constant and prolonged combat readiness, the suddenness of their action, and the difficulty of disarming them. Naval mines may be set in enemy waters and along one’s own coast. They consist of a charge of explosives contained in a watertight case that also holds instruments and devices to explode the mine and to provide safety in handling.

The first attempt to use a floating mine, although it was unsuccessful, was made by Russian engineers during the Russo-Turkish War of 1768–74. In Russia in 1807 the military engineer I. I. Fittsum designed a naval mine to be exploded from shore by a fire-conducting hose. In 1812 the Russian scientist P. L. Shilling designed a mine that was exploded from shore by means of an electric current. In the 1840’s and 1850’s, Academician B. S. lakobi invented an electrochemical mine, which was set under the surface of the water on a cable with an anchor. These mines were first used during the Crimean War of 1853–56. After the war Russian inventors such as A. P. Davydov developed impact mines with mechanical fuses. Admiral S. O. Makarov, inventor N. N. Azarov, and others developed mechanisms for automatically setting mines at assigned depths and improved procedures for laying mines from surface ships. Naval mines were used extensively in World War I (1914–18). In World War II (1939–45) proximity mines (primarily magnetic, acoustic, and magnetoacoustic) appeared. Clock delay mechanisms, ship counting devices, and new antisweep devices were introduced in the design of proximity mines. Aircraft was used extensively for laying mines in enemy waters.

Depending on their carriers, naval mines are divided into ship mines (dropped from the deck of a ship), submarine mines (fired from the torpedo launchers of submarines), and aviation mines (dropped from aircraft). According to their position after being laid, naval mines are divided into anchored, bottom, and floating mines (the mines are held at a given distance from the surface of the water by means of certain devices). By type of fuses they are divided into impact mines, which explode upon contact with a ship; proximity mines, which explode when a ship passes at a certain distance from the mine; and engineer mines, which are exploded from a command point on shore.

Impact mines may be electrochemical, mechanical, and antenna mines. The fuses of impact mines have a primary cell whose current (when a ship touches the mine) completes the electrical firing circuit inside the mine by means of a relay, causing the charge of the mine to explode. Anchored and bottom proximity mines have highly sensitive fuses that react to the physical fields of a ship when it passes near the mine (the changing magnetic field, sound oscillations, and the like). Magnetic, induction, acoustical, and hydrodynamic or combined mines are distinguished by the type of field to which the proximity mine reacts. The circuit of an proximity fuse includes an element that reproduces changes in the external field related to the ship’s passage, an amplification channel, and an activating device (firing circuit). Engineer mines are divided into mines controlled by wires and radio-controlled mines. Several methods are used to make it more difficult to counter proximity mines (minesweeping): a clock delay mechanism may be included in the fuse circuit to prevent the mine from becoming live for any necessary period; ship counting devices can cause the mine to explode only after there have been a given number of influences on the fuse; and boobytrap instruments can cause the mine to explode when an attempt is made to disarm it.