Armor Technology

In the past decades, there has been a revolution in armor technology. Research and new developments have come from Europe, the United States, and Israel. These improvements are continuing worldwide, and the antiarmor crewman must keep up with them. These improvements are also becoming much more common in third world armies, so the antiarmor crewman must expect to meet them wherever he goes. In addition, many older tanks and other AFVs are being retrofitted with improved armor protection, so it is not just the newer vehicles we need be concerned with. These advanced armor configurations improve the vehicles’ survivability against all weapons, but for the most part they are specifically designed to protect against HEAT warheads. This is a complex technical subject, and growing more so every year, but essentially these improved types of armor fall into four categories.

1. Reactive Armor. Originally fielded by the Israeli Army, reactive armor appeared shortly after on enemy tanks. Reactive armor comes in several varieties, but the principle is essentially the same on all. The armor consists of blocks of explosives sandwiched between two metal plates and bolted on the outside of the vehicle. Small-arms and artillery shrapnel will not set off the blocks. However, when a HEAT round strikes the block, the explosive ignites and blows outwards. The blast and the moving steel plates disperse and deflect the jet of the HEAT warhead, dramatically reducing its ability to penetrate armor. Many countries are now fielding different versions of reactive armor. One of its advantages is that it can easily be retrofitted onto older vehicles.
2. Applique Armor. Applique armor is essentially extra plates mounted or welded on top of the hull or turret of a vehicle. They can be made of any material, but are frequently made of ceramic or laminated materials. Like reactive armor, applique armor is an easy and cost-effective way of improving the protection of older vehicles.
3. Composite Armor. Composite armor consists of a nonmetallic core (usually some kind of ceramic) around which the rest of the steel of the hull or, more commonly, the turret, is molded. This is much more effective than conventional steel armor against all types of weapons, but less so than laminated armor. However, it is less difficult and expensive to manufacture. Hulls made of composite armor do not have to be slab sided, like those made of laminated armor.
4. Laminated Armor. Laminated armor was developed in the West, most specifically by England, the United States, and West Germany. It consists of flat layers of steel armor plate with layers of ceramics, fiberglass, or other nonmetallic materials in between. This armor is highly effective against all types of weapons, but is difficult and expensive to manufacture. Vehicles with laminated armor are characterized by flat, slab sides, such as on the M1 and Leopard II.

For combating armored vehicles, particularly tanks, it is previously known to use different types of antitank ammunition. Such ammunition is designed to penetrate even thick armor plates. Armor piercing shells are a special type of anti-tank ammunition which is provided with a hollow charge warhead. In principle, a hollow charge warhead comprises an outer casing, a metal cone and an explosive. when the explosive detonates, the metal cone is squeezed together and a metal jet is formed which, with great force, penetrates even very thick and hard armor. By virtue of its good effect in armored targets, the hollow charges have long constituted a serious threat to armored vehicles.

Due to the development that has taken place on the protection side through the introduction of composite armor, active armor, etc, the importance of improving the penetrability of the warhead has, however, increased. Armored targets can be equipped with active armor in the form of separate mountings placed in front of and at a distance from the main armor of the target. Such active armor may typically comprise two steel plates with an intermediate layer of pentyl explosive paste. Normally, active armor of this kind will disturb the hollow charge jet of the shell, its penetrative ability being drastically reduced due to the fact that the jet is broken up into fragments which tumble and are dispersed.

Increased levels of unconventional or asymmetric warfare have led to the need to protect vehicles and/or personnel from munitions typically used in this type of warfare, such as small arms fire and improvised explosive devices (IEDs). While a variety of means are available to minimize casualties from these threats, such as increased training and "render safe" procedures, the use of armor shielding remains an important last line of defense. As a result of the need to protect a large number of potential targets while not hindering their mobility, it is also important to be able to provide armor shielding that is lightweight and relatively inexpensive.

The reactive armor system is preferably not lethal to people standing nearby when fired. The concept of non-lethality is generally understood to one skilled in the art in the relevant field with reference to the US Department of Defense Directive 3000.3, which defines non-lethal weapons as weapons that are explicitly designed and primarily employed so as to incapacitate personnel or materiel, while minimizing fatalities, permanent injury to personnel, and undesired damage to property and the environment, and that are intended to have relatively reversible effects on personnel or materiel and/or affect objects differently within their area of influence. As also set forth in the US Department of Defense Directive 3000.3, non-lethal weapons shall generally not be required to have a zero probability of producing fatalities or permanent injuries, but when properly employed, should significantly reduce the probability of producing the same.