How Iran breached Israel’s air defence by overwhelming it with missiles

Millions of Israelis scrambled for cover amid air raid sirens as Iran fired more than 180 ballistic missiles into the Zionist state on October 1, the latest escalation in a growing conflict that is threatening to drag the entire region into a broader war.

The attack proved yet again that Israel’s much-vaunted air defence system—said to be the “most effective, most-tested missile shield the world has ever seen”—is far from impenetrable.

As the missile defence system came under the spotlight, security experts rushed to analyse its weak spots and how it was overwhelmed by the missile barrage.

“Iran’s strategy of launching missile barrages is designed to saturate air defence systems and force the Israelis to make tough choices about which to engage and which to let pass under significant time constraints,” Samuel Hickey of the Center for Arms Control and Non-Proliferation tells TRT World.

Israel said it intercepted a “majority” of the ballistic missiles, which means the interception rate was less than 100 percent. Rear Admiral Daniel Hagari, a spokesperson for the Israeli forces, said Iranian missiles hit central and southern Israel.

However, Iran’s Revolutionary Guards Corps (IRGC) insisted that 90 percent of its missiles hit the intended targets.

It was the largest ballistic missile strike on any country in history.

“We still don’t know if the missiles that appeared to breach Israel’s air defence systems had their payloads intact or reached their intended targets,” Hickey says, noting that Iran seemingly launched some of its more advanced missiles in the October 1 attack.

Tehran intended to inflict significant damage on Israel by oversaturating Israeli air defence, particularly in central Israel.

That’s because the number of ballistic missiles fired was about 180, notably higher than the approximately 120 similar projectiles it hurled at Israel in an earlier attack on April 15.

How Israeli air defence system works

Israel has a three-tier air defence system. The first or bottom tier is the most talked about Iron Dome, which intercepts short-range, surface-to-surface rockets of up to 70-kilometre range.

David’s Sling is the middle tier that intercepts medium-range missiles of up to 300 kilometres.

The third tier consists of Arrow 2 and Arrow 3 defence systems meant to intercept medium- and long-range missiles of up to 2,000 kilometres.

A number of mobile “batteries” of air defence systems deployed around big cities help Israel detect any projectile before it enters its air space.

Based on the trajectory of an incoming rocket, the system quickly estimates the precise impact location. If the anticipated site of the impact is far from populated areas or military installations, the system lets the rocket land without interception.

Otherwise, the air defence system quickly fires an “interceptor missile” aimed at pulverising the moving rocket before it can land inside Israel.

Tel Aviv likely anticipated the possibility of some missiles breaching its defence systems, Hickey says.

“Israeli defence planners are aware that no system can guarantee 100 percent interception. Iran's missile programme has consistently been a significant focus of Israeli intelligence, and Israeli officials have likely accounted for the limitations of their defence systems in such scenarios,” he says.

It is the third time Israel’s air defence systems have become overwhelmed by a massive number of missiles entering its airspace at once.

First, an intense rocket barrage from Hamas in the surprise attack on October 8 last year saturated Israel’s air defence system. Then Iran launched a missile attack against Israel on April 15, leaving Israeli air defence systems overwhelmed.

“Even with a strong intercept record, the offence-defence race dramatically favours the offence,” he says.

According to a report by the Institute for the Study of War, a higher number of missiles fired by Iran in the latest attack targeted a “very small geographic area in densely populated” parts of central Israel.

It means all missiles hurtling towards the densely populated area presumably needed interception.

“The increase [in the number of] in ballistic missiles may have been designed to overwhelm the Israeli Arrow ballistic missile defence system by saturating it,” it said.

Hickey says each attack, especially one that partially breaches defences, provides data for improving interception algorithms, tactics and technology.

“Israel is likely to analyse any weaknesses or failures in its missile defence response and adapt accordingly… States must only overwhelm defences by saturating key target areas with incoming missiles.”