Kinetic Energy Penetrator

A kinetic energy penetrator (also known as a KE weapon) is a type of ammunition which, like a bullet, does not contain explosives and uses kinetic energy to penetrate the target.

The term can apply to any type of armour-piercing shot but typically refers to a modern type of armour piercing weapon, the armour-piercing fin-stabilized discarding-sabot (APFSDS), a type of long-rod penetrator (LRP), and not to small arms bullets.

The opposite technique to KE-penetrators uses chemical energy penetrators. There are two types of these shells in use: high explosive anti-tank (HEAT) and high explosive squash head (HESH). They have been widely used against armour in the past and still have a role but are less effective against modern composite armour, such as Chobham as used on main battle tanks today.

The principle of the kinetic energy penetrator is that it uses its kinetic energy, which is a function of mass and velocity, to force its way through armour. If the armor is defeated, the heat and spalling (particle spray) generated by the penetrator going through the armor, and the pressure wave that would develop, would destroy the target.

The modern KE weapon maximizes KE and minimizes the area over which it is delivered by:

• being fired with a very high muzzle velocity
• concentrating the force in a small impact area while still retaining a relatively large mass
• maximizing the mass of whatever (albeit small) volume is occupied by the projectile—that is, using the densest metals practical, which is one of the reasons depleted uranium is often used.

This has led to the current designs which resemble a long metal arrow.