Reactive armour

Some tanks use special armor.

This armor helps keep them safe. It can be made of metal plates. An explosive is tucked inside the plates.

When a shot hits the armor, the explosive goes off. This pushes the metal plates apart. The moving plates hit the shot.

This helps stop the shot from getting through. Some armor uses rubber instead of explosives. This kind is lighter and safer to touch.

It is a smart way to protect big vehicles.

Tanks use special armor to stay safe. This is called reactive armor. It helps protect vehicles from heavy shots.

The most common type is explosive reactive armor, or ERA. ERA is made of metal plates. An explosive is tucked between them. When a shot hits the armor, the explosive goes off. This pushes the metal plates apart very fast. The moving plates hit the incoming shot. This can break a long rod or change the angle of a jet.

Some armor does not use explosives. This is called NERA. It uses a layer of material like rubber between plates. When a shot hits, the energy makes the plates bulge. This makes the armor feel thicker to the shot. NERA is lighter and safer for people nearby.

There is also a new idea called electric armor. It uses power to send energy into a shot. This might even turn the shot into a gas. Scientists are still studying these ways to protect tanks.

Reactive armour is a special kind of protection for vehicles. It is used to keep modern tanks safe from powerful weapons. These weapons often use shaped charges or hard metal rods to pierce through steel.

This armour works by reacting to a strike. It is much more active than just a thick wall of metal. It helps stop the energy of a hit from reaching the crew inside. This makes it a vital tool for protecting soldiers in many different lands.

The most common version is called explosive reactive armour, or ERA. It is made of metal plates with an explosive layer sandwiched in the middle.

When a weapon hits the armour, the explosive detonates instantly. This force drives the metal plates outward very quickly. The moving plates hit the incoming projectile to damage it. This process can change the angle of a jet or break a metal rod. It also forces the jet to cut through fresh material as the plates move.

People have been studying ways to disrupt these shots for a long time. Australia was the first nation to find ways to spread out the power of a hollow charge shell. In June 1944, researchers in Australia looked for ways to stop Japanese 75 mm shells. They tested using explosives or oxidisers to destroy the incoming jet. Later, in 1949, a scientist in the USSR named Bogdan Voitsekhovsky proposed the idea of counter-explosions. By the 1960s, the first models of ERA were being produced.

Many different countries use these technologies today. Israeli tanks used reactive armour during the 1982 Lebanon war.

The Soviet Union and its former states have used ERA since the 1980s. You can see it on many tanks like the T-55 or the T-90S. The U.S. Army uses it on Abrams tanks as part of a kit called TUSK. Some armour, like the Kontakt-5, uses very thick plates to stop even long rods. Other types like NERA do not use explosives and are safer for people nearby.

Think of reactive armour like a shield that moves to meet a blow. While normal armour just sits there, reactive armour fights back.

Some new ideas even look at using electricity. This called electric armour uses power to send energy into a hit. It might even turn a projectile into a gas or plasma. Scientists are still exploring these ways to make vehicles even safer. It is a constant race to find better ways to protect living things.

Reactive armour is a specialized type of vehicle protection. It is designed to defend vehicles, particularly modern tanks, against anti-vehicle munitions. These weapons often use shaped charges or hardened kinetic energy penetrators to pierce metal.

Reactive armour is highly effective against these specific threats. It works by reacting to the strike itself to disrupt the incoming force. This makes it a vital tool for protecting crews in modern combat.

The most common type is explosive reactive armour, or ERA. An ERA element consists of a high explosive layer sandwiched between two metal plates.

When a penetrating weapon strikes the armour, the explosive detonates. This detonation forcibly drives the metal plates apart. This movement is intended to damage the incoming penetrator through two main mechanisms. First, the moving plates change the angle and velocity of a shaped charge jet. Second, as the plates move outward, the impact point shifts. This forces the jet to cut through fresh metal, which increases the effective thickness of the armour.

There are several different types of reactive armour used today. ERA and its variant, self-limiting explosive reactive armour (SLERA), use explosives to drive plates apart. However, these can be defeated by tandem-charge weapons that fire two shaped charges in rapid succession. Other types include non-energetic reactive armour (NERA) and non-explosive reactive armour (NxRA). These do not use explosives. Instead, they use an inert liner, like rubber, between metal plates.

When struck, the impact energy causes the liner to bulge. This bulging shifts the impact point just like ERA, but it is much safer for nearby infantry. NERA and NxRA can also withstand multiple hits in the same area.

Research into these systems has a long history. Australia was the first nation to develop methods to disrupt the jet of a hollow charge shell. In June 1944, Australian researchers sought to defend against Japanese 75 mm hollow charge shells. They experimented with using explosives or oxidizers to destroy the incoming metal jet. Later, in 1949, academician Bogdan Voitsekhovsky proposed the concept of counter-explosion in the USSR. While early Soviet prototypes faced setbacks in the 1960s, research resumed in 1974. Eventually, joint research between a West German researcher and the IDF led to effective armour used in the 1982 Lebanon war.

Modern tanks use various scales of this technology. The Soviet-developed Kontakt-5 uses very thick and heavy plates. This version is powerful enough to break apart penetrating rods that are longer than the ERA is deep.

However, even Kontakt-5 may struggle against modern fin-stabilized discarding sabot (APFSDS) projectiles made of depleted uranium. In the United States, the Army uses reactive armour on Abrams tanks through the TUSK package. Many older tanks, such as the T-55 and T-62, have also had ERA tiles added to them. This allows older vehicles to remain useful in modern military inventories.

Using reactive armour involves certain risks and specific applications. ERA tiles are typically added as appliqué armour to the most vulnerable areas. These include the front of the hull, called the glacis, and the sides of the turret. Because the plates can explode and create shrapnel, infantry must stay at a distance during operations. This danger exists because the combined energy of the projectile and the explosive often causes the plate to shatter. Despite these risks, the protection provided to the vehicle's crew is often considered essential.

Scientists are also looking toward the future with electric armour. This is also known as electromagnetic armour. It consists of conductive plates separated by an air gap or insulating material to create a high-power capacitor. When a projectile penetrates the plates, it closes an electrical circuit. This discharges a massive amount of energy into the penetrator. This energy might even turn the projectile into plasma, which is a highly energized state of matter. While this technology was proposed by the 1990s, it had not been seen on operational platforms as of 2005.