Research, Technology

What are HEAT shells or how to melt armor

With the advent of armored vehicles between shells andthe thickness of the armor arose a certain race. The more protected the tanks became, the more powerful the shells were made to hit them, and vice versa. However, during the Second World War, this axiom ceased to exist, as they appeared that could pierce any armor, almost regardless of its thickness. The high efficiency was due to the fact that the products of their explosion did not dissipate like conventional projectiles, but were concentrated and directed by a jet to one point. Such shells are called cumulative. Since they have a small radius of destruction, they are ineffective against infantry, but they can be used not only against armored vehicles, but also against concrete fortifications. Next, we will analyze in more detail how this weapon works, how it works and what types of protection against it exist.

HEAT projectiles are designed to destroy armored vehicles


  • 1 Cumulative projectile - principle of operation
  • 2 Dynamic protection of tanks against HEAT projectiles
  • 3 Combined booking
  • 4 Tandem HEAT projectiles
  • 5 Types of cumulative weapons

Cumulative projectile - principle of operation

Unlike the classic projectile,cumulative instead of a blank contains a hollow cone. In the warhead of the charge there is another funnel-shaped cavity with a wall thickness of 1-2 mm, which is called a cumulative recess. This recess is located with a wide edge towards the target, and an explosive is located around it.

At the time of detonation of the explosiveUnder the influence of a blast wave, the walls of the funnel “collapse”, while the metal turns into a liquid, which, with a powerful jet at a speed of several tens of kilometers per second, breaks out towards the target. The pressure and temperature of the jet is so high that even the strongest armor cannot withstand and melts.

Sectional HEAT projectile

For the greatest effectiveness of such projectiles, inthey use explosives with a high detonation velocity. These include RDX, various mixtures and alloys with TNT. The effectiveness of projectiles, or armor penetration, depends on several factors, such as the material from which the walls of the cumulative recess are made, the size of the recess, the design of the detonator, and the size and mass of the charge itself.

What happens to the tank after it hitscumulative projectile? Inside, the pressure rises sharply, as a result of which the ammunition detonates. In this case, the crew receives injuries incompatible with life. For example, during the Second World War, there were cases when a cumulative jet literally cut tankers in half.

Dynamic protection of tanks from HEAT projectiles

A new type of shells demanded from armored vehiclesnew protection systems. Therefore, to increase the survivability of armored vehicles, external or active sources of protection were invented, which include dynamic protection (DZ). Surely you have noticed that modern tanks are hung with metal "bricks". At the moment the projectile hits, they extinguish the energy of the cumulative jet.

The dynamic protection of the tank extinguishes the energy of the cumulative jet

Even during the Second World War, it was noticed thatthat when the products of the explosion are exposed to the cumulative jet, it loses the ability to “burn through” the armor. There were cases when tanks carrying explosives or ammunition on their armor generally remained intact after a direct hit.

In the USSR, a lot of research was carried out andtrials in this area. As a result, it was proposed to use DZ as a protection for tanks from a cumulative projectile. However, during the development, engineers had to face a number of difficulties. The fact is that for reliable protection of armor from a shaped charge, a large amount of explosive is required, which in itself can pose a danger to the protected object. As a result, the first prototypes of dynamic protection appeared only in the 60s.

To reduce the amount of explosive indynamic protection, it was decided to use it as an auxiliary element that shoots metal plates. That is, when the cumulative jet passes through the DZ, as a result of the detonation of the explosive, plates of solid, durable steel fly out towards the charge. They, together with the explosive, extinguish the energy of the projectile. Modern DZs are capable of reducing the armor penetration of HEAT projectiles by 50-80%. Accordingly, the hit of a cumulative projectile often does not become fatal for tanks.

Dynamic protection in section

Combined booking

Combination booking is passivea way to protect armored vehicles from cumulative projectiles. The principle is quite simple, based on the use of several layers of armor in armored vehicles, with the laying of heat-resistant materials between them. In this case, the cumulative projectile destroys only the outer layers of the armor.

It must be said that the development of a combinedArmor began in the USSR and the USA as early as the 1950s. However, for the first time it was used in series on the Soviet T-64 tanks, the production of which began in 1964. Other countries began to apply this technology on serial tanks only from the end of the 70s and the beginning of the 80s.

Tandem HEAT projectiles

We figured out how dynamic protection works −it provides a barrier to the path of the cumulative jet. However, weapon developers have created new types of cumulative projectiles that are able to overcome the DZ or the first layer of armor in the case of combined booking.

Modern 125 mm shells can haveprimary and secondary shaped charge. Such shells are called "tandem". The primary charge is contained in the warhead and provides a premature response to dynamic protection. The secondary charge, which strikes the armor, is in a cylindrical body.

Tandem munition design

For example, the warhead of an American missileanti-missile complex (ATGM) "Javelin" has a tandem cumulative design with an electronic delay in the detonation of the main charge. To protect the main charge from detonation as a result of the shock wave after the detonation of the primary charge, it is equipped with an explosion-absorbing screen made of composite materials.

American man-portable anti-tank missile system "Javelin"

I must say that in the instructions for the Javelin ATGMit is stated that the ammunition overcomes all existing types of dynamic protection. However, the developers of the domestic DZ "Relic" argue that the use of special plates ensures the destruction of the funnel of the main shaped charge. That is, they are effective against any cumulative projectiles.

Russian ATGM "Kornet"

The most formidable Russian anti-tank systems at presenttime is the Kornet missile system, which penetrates 1300-1400 mm armor or 3000 mm thick concrete. In other words, it is capable of hitting any modern tank, but we will talk about it another time. Thus, cumulative munitions, which were created during the Second World War, remain relevant in the 21st century.

Finally, we suggest that you familiarize yourself with more modern weapons that can hit not only armored vehicles, but also enemy shelters. We are talking about vacuum bombs and shells.