Mine (warfare)

I

Introduction

Mine (warfare), explosive concealed underground or underwater, used primarily by military forces for defense purposes. The first mines were chambers or tunnels dug under fortifications and filled with explosives. They exploded as part of a larger attack. Today mines are self-contained explosives that explode when a target either touches them or passes close by. Areas where mines have been placed are known as minefields. See also Bomb.

Mines represent an extremely dangerous threat to troops and ships because they are difficult to detect. They can make an attacking force slow down, or make the force avoid the mined area altogether. Because mines do not require people to operate them, their use enables the defending force to focus its military personnel elsewhere. Mines are easy to lay, and once laid, a minefield does not need to be maintained.

Land mines can be made simply with inexpensive materials, and they require little training and no specialized tools to plant them. These advantages, combined with their low price, have led to their widespread use in civil wars and rebellions. Underwater mines, known as naval mines, are more expensive and sophisticated because they must endure in water for long periods of time and generally require special equipment or aircraft to lay them.

Naval mines were used extensively in World War I (1914-1918), World War II (1939-1945), and the Vietnam War (1959-1975). Land mines first saw widespread use in World War II, but they have since appeared in almost every military conflict. Today land mines threaten civilians in many countries long after wars in those areas have ended, and many people and organizations have pushed for a ban on anti-personnel mines (mines meant to harm people).

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II

Land Mines

Land mines are grouped into two broad categories, depending on whether they target people or tanks. Antipersonnel mines hurt or kill troops when triggered and are designed to explode in various ways, whereas antitank mines are designed to disable or destroy tanks and other large vehicles.

A

Antipersonnel Mines

Most antipersonnel mines consist of an explosive and a detonator (a device that triggers a mine explosion). The explosive and detonator are packed in a case made of plastic, steel, wood, or even cardboard. Antipersonnel mines are small, and can range in weight from as little as 100 g (3.53 oz) to 2.5 kg (5.5 lb) or more. Most mines depend on the force of the explosive blast for their lethal effect. Other types have fragmenting cases similar to grenades that send out deadly metallic splinters. Stepping on a pressure-sensitive button on the mine usually triggers the detonator. Other mines use thin tripwires that extend outward from the mine on the surface. When a tripwire is disturbed, the detonator is triggered and the mine explodes.

Some antipersonnel mines use a directed blast that can be aimed by placing the mine in a certain direction. The claymore is a curved mine that contains 700 steel balls backed by an explosive. When a trip wire triggers the mine, the blast sprays the balls out in a fan-shaped pattern that is lethal up to 50 m (160 ft) away. Because they fire in only one direction, claymores can be used close to defending troops without harming the troops.

The so-called Bouncing Betty mine is an antipersonnel mine that has a two-stage action when triggered. First, a small charge pops the mine up out of the ground to about waist level. A larger bursting charge then blows 300 steel balls in all directions. Such bounding mines may also spray fragments. Newer antipersonnel mines, referred to as smart mines, have a self-destruction feature that explodes the mine after a predetermined time, so it will not be a hidden hazard forever.

B

Antitank Mines

Antitank mines are similar to antipersonnel mines, but they generate a much larger blast and require heavier pressure to set them off. Antitank mines average in size from 9 to 16 kg (20 to 35 lb). Tanks are heavy armored vehicles that move on large metal tracks, or treads. A mine explosion under a tank tread will often knock the tread off, immobilizing the vehicle and possibly trapping other tanks behind it. If the mine goes off under the hull, it can destroy the tank.

Most antitank mines go off on contact, but some are designed to count a preset number of pressures before going off. By delaying detonation, a large number of enemy vehicles and troops might travel deep within the minefield before knowing the area is dangerous. During the occupation of Afghanistan by the Union of Soviet Socialist Republics from 1979-1989, Soviet forces used acoustic (sound) or seismic (vibration) sensors to set off antitank mines. A mine called the M93 Wide-Area Munition (WAM), developed by the United States, can pick up vibrations from tanks that are several hundred meters away, then target the loudest of the vibrations as the target passes by.

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