Test of endurance for Israel as one in 10 Iranian missiles penetrating defences

Interceptors failing to stop Fatah-1 hypersonic missile as war descends into numbers game

An Iranian Fatah-1 hypersonic ballistic missile. The weapon is understood to be the biggest threat to Israel, by penetrating its defence systems. AFP

One in 10 Iranian missiles are cutting through Israeli air defences with a pan-Middle East exchange of attacks now becoming a battle of resources, experts have told The National.

Iran is thought to be deploying its hypersonic Fatah-1 missiles, capable of flying at up to 18,600kph while manoeuvring in flight, making them difficult to intercept.

A battle of numbers is also developing, with the amount of relevant missiles Iran has, estimated at about 2,000, compared to the stockpile of Israel’s interceptors that has rapidly been used up in four days of bombardment.

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Crucial to the outcome of this long-range war will be which side has the most missiles. If Israel’s world-leading Iron Dome, Arrow and the David’s Sling layered system runs out of interceptors, then its cities and industrial centres will be vulnerable to Iran’s missile fleet.

The Iron Dome air defence system fires to intercept missiles during an Iranian attack over Tel Aviv. AP

But if Israel manages to fend off the offensive – it is estimated Tehran has used 280 of its total stockpile – there will be no deterrent from further attacks.

Israel on Monday claimed it had destroyed a third of all Iranian missile launchers and now “controls the skies over Tehran”, although experts say its own missile interceptor stocks are “running low”.

Bleed through

Key to Iran’s successes in penetrating defences has been the Fatah-1 missile that entered service only two years ago. The medium-range missile travels on a fixed trajectory until a few hundred kilometres from its target when its movable nozzle is initiated, increasing speed threefold to up to Mach 15, allowing it to change course frequently.

That tactic is designed to throw off the calculations of Israel’s long-range radars that can track the threats, predicting impact points.

The ability to intercept a fast-moving missile high in the atmosphere is “phenomenally complex”, said Nick Brown, director of equipment intelligence at Janes, the defence intelligence company. These missiles operate in what is called exo-atmospheric flight, or outside Earth's atmosphere.

“The pure physics of making an exo-atmospheric or very high-speed interception within the atmosphere – basically making sure your interceptor is going to be in the right place at the right time – is phenomenally complex,” Mr Brown told The National.

Damage from an Iranian missile strike in Tel Aviv. Reuters

The defenders could likely to fire two or three interceptors for every incoming missile, for which, with each Arrow-3 costing $3 million, there is a finite amount.

While Israel has good protection around its major cities, as well as military sites and key national infrastructure, it cannot protect the entire country, hence why some towns have been hit.

And even with the missile defence, Tel Aviv and the northern industrial city of Haifa have been struck. “If Iran can get enough missiles in the air simultaneously, some of them will likely bleed through,” Mr Brown said.

Reduced stocks

To win the missile war and reduce the negative political impact of a high civilian death toll, Israel will be heavily reliant on its sophisticated layered defensive system.

The key defence against high-speed missiles are the Arrow-2 and Arrow-3 interceptors – the latter is an exo-atmospheric system – that can take out threats along the arc of a ballistic trajectory.

Dr Sidharth Kaushal, an expert on missile technology at the Rusi think tank, said Israel has achieved a “high success rate of around 90 per cent” and the number of missiles “leaking through the Israeli defensive system is not especially high”.

An Arrow-3 hypersonic anti-ballistic missile is launched

“No system provides preclusive defence and if a system is saturated with enough missiles, some will get through."

But he warned the interceptors themselves, especially the Arrow-2 local coverage weapons, had unknown stockpiles and “the fact that the US has deployed a destroyer to abet the defence and is apparently considering further deployments would suggest that there is a meaningful risk of Israeli interceptor stockpiles running low”.

Poor accuracy

Most of Iran’s arsenal is based on the Shahab-3, a ballistic missile that once fired follows the same trajectory making it easier to shoot down.

But if the Shahab pierces defences – its accuracy is also quite poor – it carries a devastating 1,200kg warhead that will impact at about 8,600kmh.

Another more effective ballistic missile introduced in 2020 is the Haj Qasem, named after assassinated former Islamic Revolutionary Guard Corps commander Qassem Suleimani, that Iran claims can penetrate advanced air defences and strike targets with precision. It travels at Mach 12 (14,800kph), with a 500kg warhead.

A Shahab-3 missile towers over an Iranian soldier. EPA

Endurance test

But the Israel air force is pounding Iran’s supplies, especially as it appears to have achieved air superiority over the country, with many missiles and their launchers now being pre-emptively struck. “As such, the outcome of the test of endurance between the two sides is not yet certain,” Dr Kaushal said.

However, without those air strikes it might be possible for Iran to overwhelm the enemy air defence systems, either “by the sheer number of attacks, or by attacking from different directions”, said Dr Marion Messmer, an expert on arms control at Chatham House think tank.

“That’s why we've seen differing success rates in terms of the interception, especially with the hypersonic glide vehicles, when they remain manoeuvrable in flight. But the fact is that Israel has managed to intercept a huge amount of these various attacks.”