When a warhead strikes the surface, the reactive layer deforms outward, disrupting the jet of molten metal that could pierce the tank.
By Hezy Laing
Israel’s role in the development of reactive armor is one of those stories where necessity, innovation, and battlefield experience converged to reshape modern armored warfare.
Although the basic idea of reactive armor was first investigated—but not used—during the Second World War, it was Israel that transformed the concept into a practical, combat‑ready technology decades later.
Reactive armor has repeatedly saved the lives of Israeli tank crews by disrupting the shaped‑charge jets of RPGs and anti‑tank missiles that would otherwise penetrate a vehicle’s hull.
Reactive armor refers to modular protective blocks mounted on the exterior of tanks and armored vehicles.
Each module contains either explosive or elastic layers sandwiched between metal plates.
When a shaped‑charge warhead strikes the surface, the reactive layer detonates or deforms outward, disrupting the focused jet of molten metal that would otherwise pierce the vehicle.
The result is a dramatic increase in survivability, especially in close‑range environments where anti‑tank weapons are most common.
Israel emerged as a pioneer in this field during the late twentieth century, driven by the harsh lessons of repeated wars and the widespread use of RPGs and anti‑tank missiles by its adversaries.
It became one of the first countries to deploy Explosive Reactive Armor operationally, initially fitting ERA modules onto upgraded M60A1 Patton tanks and later integrating them into the Merkava series.
In urban battles and close‑range ambushes, ERA blocks have absorbed or deflected hits that once proved fatal, giving crews crucial seconds to survive, maneuver, and return fire.
These early Israeli designs placed explosive material between steel plates engineered to blast outward at the moment of impact, blunting the penetrating jet and giving crews a far better chance of surviving hits that would previously have been catastrophic.
Over time, Israel refined and diversified its reactive armor systems.
The IDF now employs several variants, including classic ERA, Self‑Limiting ERA designed to reduce collateral blast, and non‑explosive reactive armor (NERA/NxRA), which uses elastic layers instead of explosives and can withstand multiple strikes.
These systems are not relics of past conflicts; they continue to evolve.
In 2025, the IDF began refitting Merkava Mk.3 tanks taken out of storage with updated reactive armor modules, reinforcing vulnerable turret sides to counter modern anti‑tank threats.
Reactive armor remains a central component of Israel’s layered protection philosophy, complementing passive armor and active defenses like the Trophy APS.
Its effectiveness in urban and close‑quarters combat—settings where Israeli armor frequently operates—has cemented Israel’s reputation as a global leader in armored vehicle survivability.
