Hypersonic missiles and European security: Challenges ahead
Picture: Ministry of Defence of the Russian Federation, Creative Commons.

Hypersonic missiles and European security: Challenges ahead

28 July 2020

As Kristina Lindborg (2020) wrote, “Humans love things that go fast: race cars, speedboats, and cheetahs. Then there’s hypersonic, which leaves plain old fast blinking in the dust”. Hypersonic technology is expected to revolutionise the way countries throughout the world can counter ballistic and nuclear attacks. With these technologies arises a new kind of arms race, putting today’s global balance of power at risk – hence the importance of highlighting the pros and the cons of these increasingly coveted weapons, and the global impact they may have.

Hypersonic weapons: a disruptive technology?

The general term of “hypersonic weapons” here refers to aircraft, missiles (other than ballistic missiles), rockets, and spacecraft that can reach speeds through the atmosphere faster than Mach 5, that is, nearly 4,000 miles per hour (Wilson, 2019). Unlike ballistic missiles, hypersonic weapons are designed to remain within Earth’s atmosphere, traveling at speeds of up to Mach 27. By staying in the atmosphere, they evade both anti-ballistic missile defences and traditional, anti-aircraft missile defences, since they fly too low for the first and too high for the second. Thus, hypersonics appear to be a true game-changer technology, as they strongly amplify the attributes of air power (speed, range, flexibility and precision), and as they offer the potential for military operations from longer ranges with shorter response times and enhanced effectiveness compared to current military systems. As the speed of hypersonics is much greater than the speed of sound, their advantage lies in their enhanced manoeuvrability, and a smoother flight path which is much harder to track than that of traditional missiles.

Technically, far-flying nuclear-tipped ballistic missiles that arc into space have already been travelling at hypersonic speeds for over 60 years. For example, the North American X-15 was a rocket-powered hypersonic aircraft of the 1960s. Three of these research aircraft were built, and one of them set a world speed record 52 years ago that still stands in the domain of hypersonic technology — Mach 6.7, or 4,520 miles per hour, at an altitude of 102,100 feet. However, conventional ballistic missiles remain highly visible on radar and fly in a predictable trajectory, making them susceptible to advanced missile defence systems. That is why today’s active research and development mostly focus on the progress that can be made regarding hypersonic flight, from materials to withstand high temperatures generated in the atmosphere, to more efficient propulsion systems, size, weight, power, guidance, communications, and other harsh-environment applications.

Source: Rawpixel.

Hypersonic weapons are specifically designed for increased survivability against modern ballistic missile defence systems.

Their resilience against ballistic missile defence systems is one of the key design objective of hypersonics (Missile Defense Advocacy Alliance, 2019). Hypersonic missiles can be launched in two ways. Firstly, they can be launched from an Intercontinental Ballistic Missile (ICBM) or Submarine-Launched Ballistic Missile (SLBM), after which the jet engines powering the missiles help them reach their full speed at the top of the atmosphere (ibid.). Secondly, they can be released from a bomber, or launched independently (ibid.). As hypersonic missiles reach high altitudes powered by rocket boosters, it makes their trajectory difficult for defence systems to predict (Roblin, 2020b).

As a consequence, hypersonic weapons have two great advantages compared to regular ballistic missiles. They can fly lower and be steered more flexibly than old-school missiles, which move in a fixed trajectory towards their impact point. On the other hand, they are simply too fast to be caught by existing air defence systems. Thus, these systems could significantly improve capabilities for future military operations.

American X-51 Wave Rider hypersonic missile technology demonstrator.
Source: U.S. Air Force.

However, Tracy (2020c), who is part of the Union of Concerned Scientists, argues that the precision and overall utility of hypersonic missiles are often overestimated. He points out that flying through the atmosphere exposes the missile to heat which may degrade the surface of the missile, thereby affecting its flight path. Secondly, the missile is exposed to wind, as well as varying levels of air density; finally, the heat around the missile risks creating a plasma that intercepts the missile’s ability to receive guidance from satellites or other sources (Tracy, 2020c). Already earlier, he had argued that satellite warning systems can detect hypersonic missiles in the same way as they would detect ballistic missiles (Tracy, 2020b). As such, he concludes that hypersonic missiles do not offer a decisive advantage compared to established technologies like ballistic missiles (Tracy, 2020c).

Despite the criticisms and challenges, multiple countries are determined to acquire and develop hypersonic technologies in the upcoming decade. Consequently, the technology could give rise to a new arms race on a global scale.

Development of hypersonic missiles: State of play

In this section, we present the state of play of development in hypersonic missiles around the world as of June 2020, as well as some related characteristics. We do not look at every system using hypersonic propulsion, but only at missiles. Cancelled projects, defensive missiles, ballistic missiles and purely technological demonstrators are not accounted for. This list has the goal of being exhaustive, but obscure or classified information may be missing.

As we can see, as of June 2020, only two nations are operating a hypersonic missile: Russia and China. The Chinese DF-ZF, and especially the DF-100 hypersonic anti-ship missile is aimed at challenging and neutralising the US Navy in Asia (Roblin, 2020a). The United States will soon join this very exclusive club of nations as they are heavily invested in these programmes, both financially and politically. We will need to wait a bit longer for a hypersonic missile to enter service in France (Samana, 2019) and India; meanwhile, Japan, Australia and the UK are the furthest behind in terms of development (Speier et al., 2017, p. 34).

Hypersonic propulsions are also currently under development for systems other than missiles, such as the Russian space plane Ayaks, the Russian anti-missiles system MPKR DP, the future European air defence system, the American counter-hypersonic missile Glide Breaker, the Japanese hypersonic commercial airliner JAXA, or the American hypersonic spy drone SR-72 (Peck, 2019; Speier et al., 2017).

Strategic implications of hypersonic missiles?

The development of hypersonic weapons raises many issues regarding the destabilisation it could create in the current global balance of power, and its ongoing lack of control throughout the world as new military technology.

Firstly, as they are capable of exceeding the speed of sound five times and leave the attacked party little time to react, hypersonic missiles may alter the offence-defence balance by making first strikes more effective and unpredictable (Speier et al., 2017: xiii). As a result, national military forces may experience a need to decentralise their command structures; disperse their key forces; maintain a constant launch readiness; and prepare for pre-emptive strikes during crisis situations, which would lead to instability and unpredictability in conflicts, especially if a large number of states obtain hypersonic missiles (Speier et al., 2017: xiii). The instability is reminiscent of the Cold War, where false alarms by early warning systems brought about a risk of full-scale global conflict by accident.

Not only are hypersonic missiles primarily offensive weapons, but additionally one should consider the possibility that future missiles are used as instruments in nuclear warfare (Klare, 2019). Klare (2019) writes that the US has mainly concentrated on weapons that can deliver conventional warheads, but that the Russian Avangard missile and potentially the Chinese DF-ZF (see picture) are designed to be equipped with nuclear warheads. Especially when compounded with the short reaction time inherent with hypersonic missiles, the uncertainty over whether an enemy missile is nuclear may increase the risk of conventional conflict escalating into a nuclear war (Klare, 2019). That is what we call “warhead ambiguity”, it is to say, the risk that a defending nation, aware of an enemy’s hypersonic launch and having no time to assess the warhead type, will assume the worst and launch its own nuclear weapons (Arms Control Association, 2019). As such, arms control agreements for hypersonic missiles have already been advocated at the current early stage of the weapons’ development.

Source: Haohan, Creative Commons.

The current international legal regime for controlling hypersonic missiles is weakened by the dismantling of Cold War-era arms control treaties. As a high-profile example, the US announced its withdrawal from the Intermediate-Range Nuclear Forces (INF) Treaty in 2019, arguing for almost a decade that Russia’s development of a ground-launched cruise missile, the 9M729 (SSC-8 Screwdriver) breached the terms of the agreement (Pompeo, 2019). Moreover, China is not a party to the treaty, which limited the agreement’s ability to provide a regime for regulating hypersonic missiles (Hursh, 2020).

Secondly, the Russian-American New START (Strategic Arms Reduction Treaty) is set to expire in February 2021 unless it is extended. Moreover, while the treaty provided for Americans to inspect the Russian Avangard weapon before the successful test, hypersonic gliders would not be covered by the technical specifications of the treaty, which require a missile to fly on a ballistic trajectory for more than a half of its flight. (Hursh, 2020; Tracy, 2020a). However, Russia has shown support for the bilateral regulation of hypersonic missiles to follow the same pattern as that of intercontinental ballistic missiles, and the United States has also been willing for arms control treaties to include hypersonic missiles (Tracy, 2020a). At the same time, China was not a party to the INF Treaty or to the NEW START, which limits these agreements’ ability to provide a regulate for hypersonic missiles, especially as China has been reluctant to accept regulation in this field (Hursh, 2020).

One possibility to impose international control over hypersonic weapons is the Missile Technology Control Regime (MTCR). The regime was originally concerned with missiles ‘capable of delivering weapons of mass destruction’ (WMD), thereby mainly restraining missiles that can deliver payloads of at least 500 kilograms, but the MTCR now also includes missiles ‘intended’ for delivering WMD in its remit (Speier et al., 2017: 42). While many hypersonic missiles would not even fit this broader definition, further modifying MTCR to address hypersonic missiles nonetheless remains one possibility (Speier et al., 2017: 42–43). The regime has 35 members, not including China, although China has so far said that it “observes a version of the MTCR” (Speier et al., 2017: 42).

The American Falcon Hypersonic Test Glide Vehicle Technology Demonstrator.
Source: U.S. DoD, DARPA.

In sum, hypersonic weapons may elevate the risk of wars escalating, which calls for an international debate on limiting the use of these weapons while the technologies are still in development (Klare, 2019). In the ideal situation, at least the United States, Russia and China as the three main developers of these weapons would be covered by the international regime (Klare, 2019). However, the prospect of such an agreement seems distant (Hursh, 2020). Until negotiations for an agreement can be begun, the three powers should aim to reduce the risk of unintended escalation through confidence-building measures. These may include information-sharing related to the range and capabilities of the weapons under development, and protocols seeking to reduce ‘warhead ambiguity’ by differentiating conventionally armed hypersonic weapons from ones with nuclear warheads. Nonetheless, the political will even for this type of measures seems scarce.

The situation and possibilities in Europe

As we saw above, France is currently the only EU Member State developing hypersonic missiles: a cruise missile and a glide vehicle. We will have to wait several years for them to be tested, and even more to enter into service. The United Kingdom also expressed their wish to acquire a hypersonic missile by 2023, and are currently working on an ambitious hypersonic turbojet engine (Bosbotinis, 2020), but no more information on the missile seems available. This means that, currently, Russia is a decade ahead in hypersonic technology compared to Europe. The US, China and Russia are going to procure and use many hypersonic missiles by 2035, while Europe lags behind (Wolf, 2020). What can Europe do about this?

Something easier said than done would be to increase European defence expenditure, especially in Research & Development (R&D). However, with the upcoming economic crisis following COVID-19, budgets will be tighter, priorities will be given to the healthcare sector, and ultimately cuts are likely to take place in defence, similar to what happened after the 2008 economic crisis.

A smarter answer would be to see how European nations could develop not one, but several mutually interoperable hypersonic missiles, and for a smaller price. A quick solution would be for all missile-building companies in Europe, such as the French MBDA and the British BAE Systems and Thales Air Defence, to work together on a common missile. Yet even if such a pan-European cooperation programme would be welcome, there is a limit to how much  industrial and technological sharing is possible. Not every relevant company of each country can always have a role: there is simply not enough work for everyone. In other words, if there are too many countries working on the same hypersonic missile, some companies would naturally end up with nothing, which would create social tensions (such as loss of jobs) but also in consequence reduces the efficiency of the national industrial and technological defence base.

A better solution would therefore be to create a very large programme containing sub-programmes of different types of hypersonic missiles between each participating nation.  Relevant knowledge in R&D from each company and country would be shared. The logic is similar to the FCAS (Future Combat Air System) programme which includes not only a Next Generation Fighter, but also a carrier drone, a new weapons system, a new engine, and a new cloud data system. In our case of hypersonic missiles, for instance, the pan-European programme could include a cruise missile, a glide vehicle, a short range cruise/ballistic missile, and/or a strategic long range guided-precision missile. At present, the idea is only hypothetical: no political discourse from any Member State is currently going in this direction.

If such a programme includes two EU Member States and three European companies, the development of hypersonic missiles could be eligible to receive EU funding through the upcoming European Defence Fund (EDF). Although the EDF has a small budget of €8 billion for 2021–2027 (subject to change), it remains a good incentive for developing pan-European defence projects.

Even the EU’s Permanent Structured Cooperation (PESCO) framework could facilitate and enable the development of a European hypersonic missile. One objective of PESCO, enshrined in the legally binding commitment 13 of the PESCO legal framework, is the development of interoperability between European armed forces (Council, 2017: 4–5). A European hypersonic missile would assure interoperability in this key cutting-edge military field, and would also be useful for supporting European land forces as a state-of-the-art ground strike capability.

In addition to offensive capabilities, it would be interesting to also consider how Europe could protect itself from hypersonic missiles. So far, current air-defence systems in Europe are almost unable to stop hypersonic missile due to their speed; the anti-missile missiles launched by these systems are not fast enough or will be launched too late (Smith, 2019; Mizokami, 2016).

This US-made German Patriot air defence system is virtually unable to intercept the new Russian hypersonic missiles.
Mark Holloway, Creative Commons

An already existing solution consists in using electronic warfare (EW) systems, such as electromagnetic weapons or laser guns. This kind of weaponry is most commonly referred to as “jamming” and can be performed on the radar or communications systems of hypersonic missiles to disable them, or for instance to make them miss their target. The problem is to get these EW weapons up and running fast enough to stop a hypersonic missile. By the time European radars detect a hypersonic missile, it can already be too late, given the high flying speed of the missile. This is why European militaries should be equipped with new ground-based state-of-the-art radars capable of detecting hypersonic weapons faster, such as the new Russian 59N6-TE radar (Vayu Aerospace Review, 2020). We can also note that there is a current PESCO project, named JISR, between Germany and the Czech Republic to develop a study showing the gaps that need to be filled in terms of EW (PESCO, 2020a). One such gap is that European forces require new radars to work alongside the current EW capabilities. Another way to better detect and track hypersonic missiles would be to create a constellation of European early-warning satellites in space, equipped with sensors capable of tracking hypersonic missiles, as the United States is currently developing for its new Space Force (Strout, 2020).

Electromagnetic railguns could be used to quickly and cheaply destroy hypersonic missiles. Railguns are very precise as they can fire energy into a very narrow point, enabling them to hit a missile travelling many times above the speed of sound. The electromagnetic ammunition of a rail gun travels at the speed of light, hence much faster than even the fastest hypersonic missile. The United States, China and Russia are all currently developing such weaponry. The Pentagon and several American industries are even working on technology which might be able to place lasers on early-warning missiles in the future, to better be able to destroy hypersonic weapons (Osborn, 2019). However, for now, it is unclear whether rail guns are sufficiently mature to stop hypersonic missiles, as railguns have the same weakness as other EW weapons: they are dependent on radars or satellites capable of quickly detecting and tracking hypersonic missiles (Osborn, 2019).

US General Atomics railgun prototype.
Petty Officer 2nd Class Kristopher Kirsop

A different approach to counter hypersonic missiles would be to create a next-generation ground-based air defence system, capable of intercepting hypersonic threats. The best example is the Russian S-500 air defence system currently under production, reportedly capable of intercepting cruise missiles flying faster than Mach 5 (White, 2020). The US has also started to develop such a system (White, 2020). Meanwhile, in Europe, another PESCO project between five countries, named TWISTER, aims at “strengthening the ability of European nations to better detect, track and counter [new threats such as hypersonic missiles] through a combination of enhanced capabilities for space-based early warning and endo atmospheric interceptors” (PESCO, 2020b). A new radar or an air defence interceptor could come out of this project. It is worth remembering that PESCO projects, and their ability to be funded through the EDF, will only significantly improve military interoperability in Europe if the EU Member States make frequent, serious and full use of them, and integrate these tools into their national defence planning (EDA, 2020).

Finally, in addition to ground-based anti-missile systems, several countries are also developing “counter-hypersonic” missiles to be launched from an interceptor jet fighter, such as the American “Glide Breaker” launched from a F15 jet. The Glide Breaker, as its name suggests, is aimed at stopping and breaking hypersonic glide vehicles like the Russian Avangard (Peck, 2019). Another example of air-launched counter-hypersonic weapons is the Russian multifunctional long-range interceptor missile system (MPKR DP), launched from MiG-31 and MiG-41 interceptor aircraft. The MPKR DP, currently under development, would dispense several hypersonic sub-missiles in order to increase the chance of intercepting hypersonic weapons (Lavrov, Kretsul and Federov, 2020). If well financed, there is no doubt that European missiles industries could also be able to develop such defensive systems during this decade as well (Wolf, ibid).

In conclusion, Europe is lagging behind. Hypersonic weapons represent a threat to European security, as they are a new disruptive technology that has now entered service in nations that are somewhat threatening to Europe. European defence actors should place priority in this decade on the development of both offensive and defensive hypersonic weapons.


Written by Audrey Quintin & Robin Vanholme, Defence Researchers at Finabel – European Army Interoperability Centre

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