Anti-tank mine
An anti-tank or AT mine is a type of land mine designed to damage or destroy vehicles including tanks and armored fighting vehicles.
Compared to anti-personnel mines, anti-tank mines typically have a much larger explosive charge, and a fuze designed to be triggered by vehicles or, in some cases, remotely or by tampering with the mine.
History
First World War
The first anti-tank mines were improvised during the First World War as a countermeasure against the first tanks introduced by the British towards the end of the war. Initially they were nothing more than a buried high-explosive shell or mortar bomb with its fuze upright. Later, purpose-built mines were developed, including the Flachmine 17, which was simply a wooden box packed with explosives and triggered either remotely or by a pressure fuze. By the end of the war, the Germans had developed row mining techniques, and mines accounted for 15% of U.S. tank casualties during the Battle of Saint-Mihiel, Third Battle of the Aisne, Battle of Selle and Meuse-Argonne Offensive.Inter-War Period
The Soviet Union began developing mines in the early 1920s, and in 1924 produced its first anti-tank mine, the EZ mine. The mine, which was developed by Yegorov and Zelinskiy, had a 1 kg charge, which was enough to break the tracks of contemporary tanks. Meanwhile, in Germany, defeat spurred the development of anti-tank mines, with the first truly modern mine, the Tellermine 29, entering service in 1929. It was a disc-shaped device approximately 30 cm across filled with about 5 kg of high explosives. A second mine, the Tellermine 35 was developed in 1935. Anti-tank mines were used by both sides during the Spanish Civil War. Notably, Republican forces lifted mines placed by Nationalist forces and used them against the Nationalists. This spurred the development of anti-handling devices for anti-tank mines.The Winter War between the Soviet Union and Finland also saw widespread use of anti-tank mines. Finnish forces, facing a general shortage of anti-tank weapons, could exploit the predictable movements of motorized units imposed by difficult terrain and weather conditions.
Second World War
The German Tellermine was a purpose-built anti-tank mine first introduced in 1929. Some variants were of a rectangular shape, but in all cases the outer casing served only as container for the explosives and fuze, without being used to destructive effect. Tellermine was the prototypical anti-tank mine, with many elements of its design emulated by later mines such as the Pignone P-1, NR 25, and M6. Because of the Tellermine's high operating pressure, a vehicle would need to pass directly overhead to detonate it. But since the tracks represent only about 20% of a tank's width, the pressure fuze had a limited area of effect.As one source has it: "Since they were pressure-detonated, these early anti-tank mines typically did most of their damage to a tank's treads, leaving its crew unharmed and its guns still operational but immobilised and vulnerable to aircraft and enemy anti-tank weapons ... During World War II they began using a mine with a tilt-rod fuze, a thin rod standing approximately two feet up from the center of the charge and nearly impossible to see after the mine had been buried. As a tank passed over the mine, the rod was pushed forward, causing the charge to detonate directly beneath it. The blast often killed the crew and sometimes exploded onboard ammunition. Now that tank crews were directly at risk, they were less likely to plow through a minefield."
Although other measures such as satchel charges, sticky bombs and bombs designed to magnetically adhere to tanks were developed, they do not fall within the category of land mines as they are not buried and detonated remotely or by pressure. The Hawkins mine was a British anti-tank device that could be employed as a mine laid on the road surface for a tank to run over setting off a crush fuze or thrown at the tank in which case a timer fuze was used.
Shaped charge devices like the Hohl-Sprung mine 4672 were also developed by Germany later in the war, although these did not see widespread use. The most advanced German anti-tank mine of the war was their minimal metal Topfmine.
In contrast to the dinner plate mines such as the German Tellermine were bar mines such as the German Riegel mine 43 and Italian B-2 mine. These were long mines designed to increase the probability of a vehicle triggering it, the B-2 consisted of multiple small shaped charge explosive charges along its length designed to ensure a mobility kill against enemy vehicles by destroying their tracks. This form of mine was the inspiration for the British L9 bar mine.
Modern
Several advances have been made in the development of modern anti-tank mines, including:- more effective explosive payloads
- use of non-ferrous materials making them harder to detect
- new methods of deployment
- more sophisticated fuzes
- sophisticated "anti-handling" devices to prevent or discourage tampering or removal.
Design
- Power of the explosives.
- Shaped charges to increase the armour piercing effect.
- Advanced dispersal systems.
- More advanced or specific detonation triggers.
Dispersal systems
There are several systems for dispersing mines to quickly cover wide areas, as opposed to a soldier laying each one individually. These system can take the form of cluster bombs or be artillery fired. Cluster bombs contain several mines each, which could be a mixture of anti-personnel mines. When the cluster bomb reaches a preset altitude it disperses the mines over a wide area. Some anti-tank mines are designed to be fired by artillery, and arm themselves once they impact the target area.Off-route mines
Off-route mines are designed to be effective when detonated next to a vehicle instead of underneath the vehicle. They are useful in cases where the ground or surface is not suitable for burying or concealing a mine. They normally employ a Misnay–Schardin shaped charge to fire a penetrating slug through the target armour. This self-forging projectile principle has been used for some French and Soviet off route mines and has earned infamy as an improvised explosive device technique in Israel and especially Iraq.Due to the critical standoff necessary for penetration and the development of standoff neutralization technologies, shaped charge off-route mines using the Munroe effect are more rarely encountered, though the British/French/German ARGES mine with a tandem warhead is an example of one of the more successful.
The term "off-route mine" refers to purpose-designed and manufactured anti-tank mines. Explosively Formed Projectiles are one type of IED that was used in Iraq, but most "home-made" IEDs are not employed in this manner.
Countermeasures
The most effective countermeasure deployed against mine fields is mine clearing, using either explosive methods or mechanical methods. Explosive methods, such as the Giant Viper and the SADF Plofadder 160 AT, involve laying explosives across a minefield, either by propelling the charges across the field with rockets, or by dropping them from aircraft, and then detonating the explosive, clearing a path. Mechanical methods include plowing and pressure-forced detonation. In plowing, a specially designed plow attached to the front end of a heavily armored tank is used to push aside the earth and any mines embedded in it, clearing a path as wide as the pushing tank. In pressure-forced detonation, a heavily armored tank pushes a heavy spherical or cylindrical solid metal roller ahead of it, causing mines to detonate.There are also several ways of making vehicles resistant to the effects of a mine detonation to reduce the chance of crew injury. In case of a mine's blast effect, this can be done by absorbing the blast energy, deflecting it away from the vehicle hull or increasing the distance between the crew and the points where wheels touch the ground–where any detonations are likely to centre.
Another way to protect a vehicle from mines was to attach wooden planks to the sides of armored vehicles to prevent enemy soldiers from attaching magnetic mines. In the close combat on Iwo Jima, for example, some tanks were protected in this manner. A Japanese soldier running up from a concealed foxhole would not be able to stick a magnetic mine on the side of a tank encased in wood. A simple, and highly effective, technique to protect the occupants of a wheeled vehicle is to fill the tires with water. This will have the effect of absorbing and deflecting the mine's blast energy. Steel plates between the cabin and the wheels can absorb the energy and their effectiveness is enhanced if they can be angled to deflect it away from the cabin. Increasing the distance between the wheels and passenger cabin, as is done on the South African Casspir personnel carrier, is an effective technique, although there are mobility and ease of driving problems with such a vehicle. A V-hull vehicle uses a wedge-shaped passenger cabin, with the thin edge of the wedge downwards, to divert blast energy away from occupants. Improvised measures such as sandbags in the vehicle floor or bulletproof vests placed on the floor may offer a small measure of protection against tiny mines.
Steel plates on the floor and sides and armoured glass will protect the occupants from fragments. Mounting seats from the sides or roof of the vehicle, rather than the floor, will help protect occupants from shocks transmitted through the structure of the vehicle and a four-point seat harness will minimise the chance of injury if the vehicle is flung onto its side or its roof–a mine may throw a vehicle 5 – 10 m from the detonation point. Police and military can use a robot to remove mines from an area.