Iskander: An Improved Russian Missile Tests Ukraine’s Air Defence

Recently, there have been a series of reports that Ukraine’s ability to intercept the Russian 9M723 Iskander-M ballistic missile with Patriot interceptors is deteriorating. Given the sensitivities around the subject, precise reasons have not been provided although several reports have alluded to software upgrades which have allowed the Iskander to manoeuvre more effectively in its terminal phase, thus evading Patriot interceptors. This article seeks to evaluate the plausibility of both this and other competing hypotheses regarding the seeming increase in the performance of the 9M723. It does not provide conclusive answers but rather an assessment of the relative weight which researchers might attach to competing explanations.

The Importance of Caution in Assessing Intercept Rates

It is worth beginning by noting that one should be cautious in interpreting data regarding intercept rates. The use of percentages predisposes readers to assume that there is, all other things being equal, a given likelihood of any missile being intercepted by a particular defensive system. In reality the data is marked by discontinuities and largely driven by specific high impact events.

Data of Russian missile strikes since September 2022 compiled by Petro Ivaniuk, a Ukrainian researcher and confirmed by CSIS, the Washington-based think-tank, shows that Ukraine’s interception rates of 9M723 have never been particularly high. The dataset up to 24 October 2025, shows that 939 Iskanders and Kinzhals have been fired at Ukraine, and just 227 have been intercepted. This represents a somewhat positive picture – it suggests that 24% of Russia’s ballistic and aero-ballistic missiles are intercepted.

However, this includes 18 events where all or most of the missiles were intercepted, out of a total of 345 attacks that included them. This is a very high success rate for those 18 attacks, and represents something of an anomaly. Interpreting the data in another way, it indicates that in just 4% of attacks, Ukraine has succeeded in intercepting most of the Iskander and Kinzhal missiles fired at it. Of those 345 attacks, in 273 instances Ukraine’s air defences did not intercept any Iskander or Kinzhal missiles. As a result, 593 missiles made it through the country’s air defences, although 22 of those missiles reportedly failed to reach their targets.

It is of note that the absence of an intercept does not imply a failure of Patriot, per se; the missile may have been employed against targets which did not receive the protection of one of Ukraine’s limited arsenal of six Patriot batteries. If one narrows the search down to attacks on locations where a Patriot launcher was known to be present (for example Kyiv and Odessa) there does appear to be a considerable deterioration of air defence effectiveness. While data still shows discontinuities, with virtually every Iskander intercepted in some months while none are in others, a downward trend is nonetheless visible and by 2025 there are no months with very high intercept rates (30% being the maximum achieved around Odessa).

Ukraine was able to intercept 37% of the ballistic missiles fired at it during the summer. From June to the end of September, 179 9M723 and KN-23 missiles were fired, 67 of them were intercepted for a percentage of 37.4% across 50 attacks. However, in 36 of those attacks no ballistic missiles were intercepted at all, meaning that Russia’s 9M723s got through in 72% of the attacks. Looking at the more successful defensive engagements, Ukraine shot down 77% of all the Iskanders it intercepted over the summer (52 missiles), in just six engagements. This included one engagement where all eight 9M723s were shot down, and another where 17 out of 27 were shot down – a 62% success rate. From 1-24 October, the data shows 78 9M723 launches, with just 14 intercepted for an intercept rate of 17%. And yet, on 22 October, six out of 11 missiles were intercepted, and four out of nine on the 25th. Looking at the period from the start of 2025 up to the summer, 128 9M723s and KN-23s were launched, of which just 20 were intercepted, or 15%.

Instead of clustering around the mean in a standard bell curve, the distribution of intercept rates is a bimodal one where often either all of the missiles in an attack are intercepted or none are. This does mean that even when intercept rates are low on average, Russian planners likely cannot simply factor the mean intercept rate into the number of missiles allocated to a target and apportion resources accordingly. This is of limited consequence against Ukraine, since Russia has the time to make multiple attempts against any target but could be a useful data point for NATO planners since, in a war against NATO, Russia would need certainty of effect against key targets and even limited air defences can deny this.

Returning to the subject of missile warfare in Ukraine, although it is important to be careful when using average intercept rates, the data broadly supports the hypothesis that intercept rates against Iskander have been on a downward trend since around 2024 when intercept rates in Patriot defended areas dropped to 15% over the year. There was a brief resurgence in the interception rates achieved in mid-2025, followed by another decline.

It is to the subject of what might be driving this latest decline that we now turn.

Hypothesis 1: Employment of a Higher Altitude Trajectory

One plausible explanation for the increase in the effectiveness of the Iskander offered by some analysts is that the Russians are firing the missile on a steeper ballistic trajectory, shortening the reaction times for air defenders. In this scenario the Iskander, which typically flies at a lower altitude quasiballistic trajectory, would be employed on a purely ballistic arc.

One intended outcome that would be sought from employing the 9M723 on this trajectory would be to provide the missile with greater kinetic energy as it descended towards its target, shortening a defender’s engagement envelope. The reason for this is twofold: At higher altitudes in thinner air, the missile is subject to less aerodynamic drag. Secondly, as a missile descends from a higher altitude its potential energy is converted to kinetic energy which is added to the energy generated by the Iskander’s motor. Finally, the steeper the angle of descent the less total aerodynamic drag a missile is subjected to.

The second advantage of a steep trajectory is that it facilitates terminal phase manoeuvre through increased lateral acceleration. Lateral acceleration is a function of dynamic air pressure which is calculated as being:

a = 0.5 × p × v^2

Where p and v are air density and velocity respectively. In effect, the potential of a missile for short bursts of lateral acceleration is a function of the square of its velocity. This means that the faster a missile moves, the more force it can manoeuvre with. This equation shows that if the speed of the missile were doubled by a steeper trajectory and faster descent, its manoeuvring force would quadruple. This has always been reported to be within the scope of the 9M723’s design. An article from 2019 published by Russia’s Union of Mechanical Engineers of Russia, states that, ‘the missile's trajectory is not ballistic, but controlled. It constantly changes its trajectory, especially during its acceleration and approach to the target.’

Consequently, a higher altitude trajectory could explain reports of the missile manoeuvring more aggressively in ways that make interceptors more likely to miss.

The cost incurred would be a reduction in the horizontal distance which the missile can cover given the energy expended in bringing the missile a higher apogee. The hypothesis that the Russians are trading range for speed would be consistent with some elements of the available data. For example, what is known about Iskander strikes over the last year would suggest a shift in emphasis in the last several months with a particular focus on the employment of ballistic missiles against known training sites in areas such as Sumy, Poltava and Kropyvyntskyi most of which are within 150-200km of Russian controlled territory. A shift in targeting which necessitated the use of 9M723 against more nearby targets might incentivise a lofted trajectory. In addition, a 2017 exercise reportedly included an Iskander ballistic missile being fired at a target 140 km away, reaching an altitude of 100 km during its flight, according to TASS. This conflicts with other reporting, which typically attributes the missile with a maximum altitude of 50 km.

However, the lofted trajectory hypothesis, while compelling, also has certain issues. First, hit to kill missiles like the PAC-3 are themselves highly manoeuvrable. It is true that the intercepting missile typically needs to be accelerated at least 1.6 times faster than its target but given the difficulty of engaging fast moving ballistic targets this is very much built into interceptor design. For example, the PAC-3 has been demonstrated against medium-range ballistic missile (MRBM) type targets which typically re-enter the atmosphere at speeds well in excess of anything which could be achieved by the 9M723 on any trajectory. It follows that engaging MRBMs likely requires the capacity for very high-g manoeuvres by the interceptor, which should in theory nullify the effect of sharp terminal phase turns by the much slower Iskander.

The PAC-2 GEM-T which Ukraine also uses may be more susceptible to the impact of greater terminal phase manoeuvrability, however. Despite there being some basis for caution in embracing this hypothesis, it remains the case that terminal phase manoeuvres enabled by high speed have been assessed to impose especially stringent requirements on air defences; both in terms of their load factor and the speed at which interceptors can integrate information from their seekers. These are critical factors, which become even more taxing for hit-to-kill missiles as they must directly impact their targets. Though not certain, then, the altered trajectory hypothesis is at a minimum plausible.

Hypothesis 2: Improving Decoys

Another explanation offered to the authors by subject matter experts is that the Iskander is now more regularly being deployed with decoys. This is not exactly new – the Iskander has been known to deploy six 9B999 decoys in the base of the 9M723.

The claims that a software upgrade is at the heart of the Iskander’s effectiveness would however be more consistent with improvements to decoys than a purely ballistic trajectory, which would involve relatively minor software changes if any (since most missiles can be programmed to fly on multiple trajectories). Given the effectiveness of the PAC-3 interceptor’s Ka-band radar at target discrimination, decoys likely had limited effectiveness, which may explain their more limited use for a period.

In theory, millimetric wave radar such as those on the PAC-3 can be decoyed, however. This requires more sophisticated equipment to feed deceptive information into a narrow radar aperture and likely some knowledge about the way in which a system processes information. The functionality of Western decoys such as the Nulka DFRM decoy system used against anti-ship missiles is, to a great extent, driven by their software, which rapidly processes the signals from a missile’s seeker and generates signals more likely to deceive it.

An improvement to the 9B999 which allowed it to rapidly target a narrow aperture seeker would explain the emphasis on software driven change and would explain the decoy’s resurgence on the battlefield. However, while this explanation passes a plausibility test, there is no concrete evidence to support it beyond the allusions to software updates on the Iskander.

Hypothesis 3: Salvos

Effective long-range strikes, especially those of the scale conducted by Russia, required considerable planning and coordination. Generally speaking, a force will aim to synchronise its effects – having multiple missiles and drones arrive at the target simultaneously or in a short space of time. Some strikes against Ukraine have included 9M723s fired from opposite directions against the same target – an air defender’s nightmare. Although overwhelming Ukrainian air defences with coordinated salvos might be the most compelling hypothesis, it is ultimately unconvincing. Iskanders are often used in conjunction with other missiles at a theatre level with many types of missile fired in any given night. The attack on 29 October involved more than 700 drones, cruise and ballistic missiles according to the Ukrainian Air Force. This included nine ballistic missiles – both 9M723 and Kh-47 – as well as 43 cruise missiles. Ukraine intercepted 21 cruise missiles and 592 attack drones but none of the ballistic missiles were intercepted.

However, in many attacks involving Iskanders, the targets hit by the 9M723 were not struck by other missiles in tandem. Moreover, large salvo sizes and the coordination of different capability types are a challenge that Ukraine has faced from the war’s outset. Depending on how the data is interpreted, it appears that Ukraine achieves better interception rates against the 9M723 when they are used in larger numbers. Additionally, by virtue of their different speed and altitude profiles, ballistic targets are relatively easy to discriminate and prioritise, if not necessarily engage. While battle management system saturation plays an important role in missile warfare, it is an unlikely explanation in this context.

Conclusion

While it is not yet possible to arrive at a conclusive answer to the question of why the rates of intercept against Iskander have seemingly declined, there are several hypotheses which bear further examination. Changes to the missile’s trajectory and the employment of more effective decoys, in particular, bear further consideration. Ultimately, the competition between missiles and air defence systems is a continuous process without a fixed end point. Consider, for example, the marked improvement in the effectiveness of tactical ballistic missile defence over the last 30 years driven in part by work done to overcome the unsatisfactory performance of Patriot in the 1991 Gulf War. The observed developments will likely drive iterative changes to Patriot, which in turn will drive Russian adaptation and so on.

It must be noted, however, that ballistic missile defence is hard at the best of times. Moreover, the very discontinuous nature of intercept data where intercept rates do not neatly cluster around the mean must always be borne in mind. It is not the case that planners on either the attacking side or the defending side can use mean intercept rates to calculate how many missiles are needed to ensure at least one hits.

For allied planners, this is the crucial detail. If a Russian attack planner cannot be sure if all the missiles fired will penetrate or be intercepted (with few intermediate results) a missile defence system which can act as a force in being – sufficient to ensure that certain outcomes cannot be achieved against high value targets, is sufficient in a campaign against NATO where Russia must be able to ensure that some targets are disabled early. The character of the data provides an important basis around which to plan tactical BMD.

© RUSI, 2025.

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