An active protection system, or APS, protects a tank or other armoured fighting vehicle from incoming fire before it hits the vehicle's armour. There are two general categories: soft kill systems, which use jamming to confuse a missile's guidance system, and hard kill systems, which attempt to detect and destroy incoming projectiles.

Land vehicle APS

Soft kill systems were (unsuccessfully) deployed by Iraq in the Gulf War. These were essentially strobe lights fitted to Iraqi tanks, which masqueraded as the guidance beacon on the back of a TOW missile. The multinational force was aware of their use, and adjusted the frequency of their guidance systems so they wouldn't be confused. A soft kill system currently in service is the Russian Shtora, deployed on Russian and Ukrainian tanks.

Hard kill systems are activated when a millimetre-wavelength radar or other sensor detects an incoming projectile. In considerably less than a second they launch a counter-projectile in an attempt to physically damage or destroy the incoming round. Examples include the TROPHY Active Protection System and Iron Fist from Israel and the Russian Drozd and Arena.

Aircraft APS

Attempts to use aircraft-mounted flak cannon as such an APS against anti-aircraft missiles proved ineffective. Anti-aircraft missiles are designed for effectiveness in a near-miss shot, making APS inefficient and unreliable. Among the effective countermeasures for aircraft are ECM, flares or anti-radar chaff.

Naval APS

Warships have been equipped with similar systems (more frequently known as CIWS) for quite some time, using small to medium-caliber (12.7-76mm) guns and guided missiles to destroy inbound missiles and cannon shells. Examples include the US Phalanx CIWS, Dutch Goalkeeper, Russian Kashtan, joint USA/German Rolling Airframe Missile, British Sea Wolf, Chinese Type 730 and Turkish Sea Zenith.

In popular culture

In the film Die Another Day, James Bond's modified Aston Martin Vanquish was portrayed with twin bonnet-mounted automatic shotguns as a hard-kill system to destroy mortar rounds.

External links

• Active Protective Systems: Impregnable Armor or Simply Enhanced Survivability? — An overview of modern tank active protection systems (PDF)
• Active Protective Systems overview - Defense Update
• Soft Kill Active Protective Systems overview - Defense Update

AFV equipment | Weapons countermeasures

System obrony aktywnej | Aktif koruma sistemi