RUSSIAN TANKS went through a hot period during the invasion of Ukraine. At least 153 of them have been destroyed so far, along with 312 armored vehicles, according to Oryx, an open-source intelligence blog. (The numbers for the Ukrainian side are 26 and 57 respectively.)
Many of these were blown up by cheap anti-tank missiles (ATGMs) worn by the Ukrainian infantry. Western countries have shipped thousands of such weapons to Ukraine, ranging from American spears to Swedish-designed ones NLAWs to German-made Panzerfaust-3s. The war was a powerful demonstration of the threat they pose to modern armaments, says Jon Hawkes, a land warfare guru at Jane’s, a British military intelligence agency. Some Russian tankers have welded junk cages to their vehicles in a dubious attempt to provide additional protection.
That’s ironic ATGMs have proven so effective because Russia—and before that, the Soviet Union—was a pioneer of so-called “active protection systems” (APSs) specially designed to defeat them. Unlike armor, which is designed to limit damage to a vehicle when hit, APSs are there to stop missile attacks in the first place. Armies around the world are experimenting with and using them. The war in Ukraine will add even more urgency to this task.
APSs come in two varieties, referred to as “soft kill” and “hard kill.” Soft-kill systems distract a missile by interfering with its guidance systems—for example, by blinding it with infrared light or lasers. Hard-kill systems are designed to destroy missiles in flight.
The war in Ukraine shows the limits of the soft-kill approach, says Jack Watling of the Royal United Services Institute, a London-based think tank. “You need a good technical understanding of the system you’re trying to defeat.” The potpourri of ATGMs used by Ukrainian soldiers has many different guidance systems. Blocking them all is impossible.
But even hard-kill systems have problems. You need sophisticated radar to detect incoming missiles and an accurate aim to hit them. Anti-tank missiles fly at hundreds of meters per second, so fast reaction times are crucial.
The Soviet Drozd system, one of the first hard-kill systems APSs, was originally deployed in the 1980s in the wake of USSR‘s invasion of Afghanistan. It fired grenades full of shotgun-like bullets at incoming missiles. Afghanit, the most recent successor to Drozd, is built into Russia’s brand new T-14 tanks. But Russia is struggling to build enough of them. As far as analysts can tell, few APS-armed tanks have been sent to Ukraine so far.
The army that is furthest along with hard-kill APSs is Israel’s. Its trophy system was designed by Rafael, a company in Haifa, and installed on the country’s Merkava tanks. Trophy fires a narrow spread of precisely aimed projectiles to minimize the threat the system poses to nearby friendly infantry. The Israeli army claims that Trophy has repelled many anti-tank missile attacks in Gaza – although Mr Hawkes notes that such attacks are likely to stem from older, less sophisticated attacks ATGMS. Trophy has also aroused interest abroad. America and Germany have equipped some tanks with it and Britain is conducting trials.
Such defenses have disadvantages. APSs take up weight, space and strength – all valuable goods in a tank. Western tanks in particular, Mr Watling says, have little room to get heavier without sacrificing performance. And hard-kill systems may only protect against a handful of incoming rounds, as debris from a successful intercept is likely to damage the sensitive radar the system relies on. Cunning enemies could rake in tanks with machine gun fire to disable that radar in advance, Mr Watling says.
But a defense doesn’t have to be perfect to be useful. Mr. Hawkes speaks of layered “onion-style” defense, where shielding detects infantry threats, smoke can obscure a tank’s position, and armor then protects the target when all else fails. Russia’s experience in Ukraine suggests that adding another layer to this onion could actually prove useful. ■
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This article appeared in the Science & Technology section of the print edition under the headline “The Best Defense Is A Good Offense”