Arrow 3 after Oreshnik

Was the German Ministry of Defense playing 3D-chess all along?

Picture: Missile Defense Agency

On 29 August 2022, German Chancellor Olaf Scholz first announced his intention to procure the Israeli ballistic missile defense system. Initially, the announcement received limited attention. However, this changed in the summer of 2023 when the Bundestag’s Budgetary Committee approved the purchase for close to 4 billion Euros.

The primary critique of the missile defense system, including my own, focused on its limited utility against the most pressing Russian threats. This was due to the system’s high engagement ceiling, which is optimized for intercepting medium-range ballistic missiles—capabilities that were not, at the time, known to be part of Russia’s missile arsenal.

However, during the night of 20–21 November, in an attack on the Ukrainian city of Dnipro, Russia unveiled a new ballistic missile called Oreshnik, which likely falls within the medium- to intermediate-range spectrum. In light of these developments, have the critics been silenced, and was the German Ministry of Defense correct all along?

Arrow 3

The Israeli ballistic missile defense system Arrow 3, developed jointly by Israeli Aerospace Industries and Boeing, entered service in 2017.

The Arrow 3 ballistic missile defense system is capable of launching both Arrow 2 and Arrow 3 interceptors, though Germany is only known to have procured interceptors of the Arrow 3 type. The Arrow 3 interceptor is a two-stage, solid-fuel system designed to engage incoming threats outside the atmosphere by guiding a hit-to-kill vehicle into the target projectile.

Arrow 3 intercepts threats at altitudes exceeding 100 km, though the exact engagement envelope remains classified. It cannot engage targets within the atmosphere, as the sensitive sensors and electronics on the kinetic kill vehicle cannot withstand the atmospheric friction encountered during endo-atmospheric flight. For this reason, Arrow 3 is unsuitable for intercepting shorter-range ballistic missiles, which remain within the atmosphere for most or all of their flight.

Germany’s Arrow 3 will employ the EL/M 2084 “Super Green Pine” radar, which detects and tracks incoming ballistic missile targets at ranges of several hundred kilometers. The radar also provides midcourse guidance to the interceptors, as well as trajectory and impact point predictions for the incoming projectile.

Germany has ordered a total of three Arrow 3 batteries. Each battery comprises four launchers, with each launcher carrying six Arrow 3 missiles ready to fire, for a total of 24 ready-to-fire missiles per battery. Across its three batteries, Germany will have 72 missiles available for immediate launch before requiring a reload. The exact number of Arrow 3 interceptors procured by Germany is unclear, but a rough estimate may put it between 150 and 250.

Enter Oreshnik

Unlike the 9M723 short-range ballistic missile or the Kh-47M2 Kinzhal, the new threat posed by the Oreshnik medium- to intermediate-range ballistic missile falls within the engagement envelope of the Arrow 3 system. However, it is unclear how well Arrow 3 is optimized for the specific type of threat Oreshnik represents.

Arrow 3 was originally designed to counter medium-range ballistic missiles typically launched by Iran and its non-state proxies in the region, with ranges of approximately 2,000–3,000 km. Oreshnik’s maximum range is likely quite a bit higher—potentially 5,000 km or more—especially when equipped with a reduced payload.

In its recent attack, Oreshnik also demonstrated the ability to follow a lofted trajectory, resulting in a steeper angle and a higher apogee. This was enabled by the relatively short distance between the missile’s launch site, located 800 km from its target, allowing the missile to convert a substantial portion of its energy into vertical ascent rather than horizontal range.

If Oreshnik were used to strike targets deeper inside central or western Europe, including in Germany, it would follow a shallower trajectory. However, there remains a good chance that it would approach from altitudes higher than those Arrow 3 is optimized to handle.

This does not mean Arrow 3 would be useless—far from it. However, high-apogee trajectories can take the missile out of the detection range of radars optimized for lower-altitude threats, such as the Super Green Pine radar used in Arrow 3. This can create gaps in tracking coverage, during which limited data is available on the missile’s trajectory. Over time, this tracking gap can degrade the radar’s predictive modeling capabilities regarding the projectile’s trajectory and impact point, ultimately reducing the probability of a successful intercept.

On a side note, this is also why I am skeptical about Arrow 3’s claimed ability to counter ICBMs, as the system’s hard- and software are simply not optimized for ICBM threats.

Numbers game

Even if the Arrow 3 system is fully capable of addressing the ballistic missile threat posed by Oreshnik, one could still question whether responding to this threat is even worthwhile.

First, the number of Oreshnik missiles Russia can theoretically deploy is highly limited, at least for now, and depends on the stockpile of early production RS-26 Rubezh missiles, on which the Oreshnik is based. It is unlikely that this stockpile exceeds 20–30 units.

Second, the lethality of Oreshnik warheads is limited due to the missile’s inaccuracy and inert payload. Unless Russia manages to score a lucky hit, the Oreshnik is unlikely to inflict critical damage on key targets.

Third, while Oreshnik’s lethality is limited, its MIRV capability creates a large number of projectiles—six per missile—that would theoretically need to be engaged, if the decision is taken to respond to an incoming Oreshnik threat. This could quickly deplete Germany’s Arrow 3 interceptor stockpile.

Overall, there is an argument, and in my opinion a very strong one, to ignore the Oreshnik threat altogether and reserve Arrow 3 interceptors for higher-priority targets. However, this raises the question what these higher-priority targets in Russia’s arsenal would be. Russia does not currently deploy highly lethal or sophisticated medium-range ballistic missiles.

Judgment call

In the end, Arrow 3 likely represents a judgment call by German decisionmakers: do you prioritize existing threats, or do you hedge against potential future ones? In my view, Oreshnik alone does not yet pose a threat significant enough to justify the massive investment into Arrow 3, especially when considering the opportunity costs.

That said, this doesn’t mean such a threat couldn’t emerge in the future. However, it would likely depend on Russia emerging from the war relatively intact, with sufficient capacity to pursue new missile R&D projects and ramp up production. For now, there remain far more pressing threats within Russia’s missile arsenal that demand attention.