The independent resource on global security

China's calculus on hypersonic glide

China's calculus on hypersonic glide
U.S. Air Force's X-37B Orbital Test Vehicle 4. Photo: Flickr/ U.S. Department of Defense
Dr Lora Saalman


Hypersonic glide vehicles are a growing factor in strategic stability calculations. Given their speed, precision and manoeuvrability, these systems are well suited to defeating missile defences. This section takes the current dyadic approach to US–Chinese competition in the field and inserts Russia as a factor that is shaping Chinese views on the subject. Presenting the key takeaways from 872 of 1675 surveyed Chinese-language texts, the author reviews more than a decade of research on hypersonic and boost-glide technologies to reveal growing Chinese interest in Russia. Combining this trend with both countries’ shared concerns over US missile defence suggests that it is time to start factoring in how Russia’s calculations on its own prompt global strike programme might shape China’s decisions on future nuclear and conventional payloads, and the targets and range of its own hypersonic glide vehicle programme.


Strategic intersection

In China, as in Russia, the US prompt global strike programme is discussed as an inherently pre-emptive and destabilizing system. Both countries make the worst-case scenario assumption that the USA will deploy a prompt global strike system that places their arsenals and command and control infrastructures at risk, whether on intercontinental ballistic missiles, air- and submarine-launched hypersonic cruise missiles, or kinetic weapons launched from an orbiting space platform. In the light of these concerns, it is not surprising that both China and Russia are exploring similar capabilities to offset or deter decapitation of their arsenals by the USA.

The timing of China’s flight test of its DF-ZF (previously designated as the WU-14) in April 2016 further highlights integration as a factor. China’s hypersonic glide vehicle test was reportedly a success and occurred just days after Russia carried out its own test. Its proximate timing to that of Russia recalls China’s previous flight tests, which often came on the heels of those conducted by the USA. This is more than mere coincidence. A review of more than a decade of Chinese writing on hypersonic and boost-glide technologies reveals growing interest in and research on Russia’s hypersonic glide vehicle programme. Combining this trend with both countries’ shared concerns over US missile defence suggests that it is time to start factoring in how Russia’s calculations on its own prompt global strike programme might shape China’s decisions on future nuclear and conventional payloads and targets, as well as the range of its own hypersonic glide vehicle.

Russia and China are not simply linked by China’s increased interest in Russia’s hypersonic glide developments. China’s renaming of its Second Artillery Corps as the People’s Liberation Army Rocket Force (PLARF) and the publication of its 2015 Military Strategy White Paper also hint at a growing convergence. The full implications of this name change and restructuring, which seemingly mirror Russia’s own Strategic Rocket Force, are unclear but there is an emerging similarity between the two forces. The PLARF commands all three legs of China’s nuclear triad and is now thought to be on an equal footing with the People’s Liberation Army (PLA), Navy and Air Force.

In addition, while China’s 2015 White Paper might not be as specific as Russia’s 2015 Military Doctrine, it emphasizes a similar vision of a global revolution in military affairs tied to long-range, precise, smart, stealthy and unmanned weapons in both outer space and cyberspace. It also details how the Second Artillery, now the PLARF, ‘seeks to improve nuclear and conventional forces and long-range precision strike capability’ and ‘is building systems of reconnaissance, early-warning, command and control, as well as medium- and long-range precision strike capabilities’. Finally, it advocates the development of ‘independent new weapons and equipment’ and fielding ‘a lean and effective nuclear and conventional missile force’.

 Thus, Chinese experts from such organizations as the China Airborne Academy in Luoyang and the China School of Aerospace Engineering at the China Institute of Technology already place a high priority on near-space attack systems as the future of warfare. China has also been increasing the manoeuvrability of its hypersonic glide vehicles, conducting simulations that leverage near space and heat reduction to allow for successful re-entry, and researching more powerful engines and better trajectory optimization to expand the range of its hypersonic glide vehicles. While the majority of these papers involve technological mirroring of US advances, a number also highlight the arc of Russia’s hypersonic and boost-glide pursuits. Chinese research into aerodynamic properties, manoeuvrability and the G-force effects on the fuselage at high speeds often feature overviews of Russia’s programmes, including its Project 4202 which spawned the Yu-70 (102E or 15Yu70) and the more evolved Yu-71 and Yu-74.

As both Russia and China seek to deploy their own version of a hypersonic glide system, they are confronted with many of the same considerations faced by the USA in distinguishing between a conventional and a nuclear payload. Nonetheless, Russia’s reported testing of its hypersonic glide vehicle on the UR-100N and the potential mounting of it on the heavy liquid-propelled RS-28 ICBM to defeat US ballistic missile defences suggest that it is making its intentions clear. Given the focus on defeating US missile defences, a nuclear payload would be the most likely option. By contrast, China has been hedging on whether its DF-ZF will be conventional or nuclear. Current discussions on mounting hypersonic glide vehicles on the DF-21 medium-range ballistic missile (MRBM) and the DF-26 intermediate-range ballistic missile (IRBM) indicate a regional contingency. This has elicited a profusion of Western analyses of China’s use of its systems for anti-access area-denial (A2AD) to complicate US regional intervention in a crisis.

What these studies disregard, however, is that roughly a quarter of the Chinese technical studies on hypersonic glide vehicles remain focused on US missile defences, rather than any A2AD agenda. Some Chinese experts are even beginning to allege that the very existence of A2AD is a fabrication by Western analysts. Roughly half the Chinese studies surveyed on hypersonic glide vehicles and related technologies concentrate on countering or developing longer-range systems, such as space planes. This suggests that the future uses of China’s hypersonic glide vehicles will extend well beyond a conventional payload and a regional conflict. The fact that they place a similar focus on Russia’s intended use of these systems to defeat US missile defences in response to US withdrawal from the Anti-Ballistic Missile (ABM) Treaty also suggests identification with Russia when confronting this threat.

Thus, when it comes to the question of whether the DF-ZF, or the Yu-71 and the Yu-74, would be used to overcome theatre missile defence (TMD) or national missile defence (NMD), Chinese and Russian analyses have similar perspectives. They do not distinguish between regional and national missile defence. Much as in Russian discussions of US deployment of TMD in Eastern Europe, Chinese debates over TMD in East Asia concentrate on how these systems serve larger US NMD reconnaissance and intercept goals, thereby threatening its strategic deterrent. This has recently come to the forefront of Chinese concerns over the intended stationing by the USA of THAAD in South Korea, in terms of both enhanced radar and intercept capabilities. Moreover, US X-Band radar deployment in Japan has been a concern for a number of years. The fact that both Chinese and Russian developments in prompt high-precision systems are trending towards the targeting of US missile defences and a nuclear payload makes the postural crossover of these countries all the more relevant.


System integration

If China’s DF-ZF is intended as a conventional weapon to be used against a non-nuclear target, then the chances of use are likely to increase. This stems from the inherent difference between conventional weapons and nuclear weapons posited by Li Bin, professor and director of the arms control programme at Tsinghua University, who argues that countries do not intend nuclear weapons for actual use, but rather for coercion—or bargaining in the case of the USA. Unlike nuclear weapons, hypersonic glide vehicles are viewed in a much more utilitarian way in Chinese texts. In part, this stems from their current use, which Western analysts assume is to be mounted on medium-range missile systems to thwart US regional intervention.

When it comes to Chinese technical and official analyses, however, China appears to be extending hypersonic glide range and utility from the regional conventional systems to be deployed on DF-21D MRBMs and DF-26 IRBMs, to longer-range nuclear systems that put US missile defences at risk. Given the pre-existing utilitarian concept of these systems as conventional weapons, building hypersonic glide vehicles into China’s strategic deterrent creates the potential for them to erode the nuclear taboo, increasing the likelihood of their use even if mounted with nuclear payloads.

The utilitarian posture in China towards hypersonic glide vehicles, which may at some point carry over to nuclear payloads, creates worrying challenges in terms of escalation and overall strategic stability. Exacerbating these challenges is the co-mingling argument made by James Acton at the Carnegie Endowment for International Peace, which posits that a conventional strike against co-located nuclear and conventional command and control centres could trigger a nuclear response. In this case, China’s own control architecture poses the greatest challenge.

China’s assumed conventional and nuclear co-location deters an adversary from launching an attack. Yet, the likelihood of such facilities being compromised in a conventional conflict remains and could result in rapid escalation. If China’s DF-ZF system is launched in response to what has been deemed a ‘first-use’ attack on a co-mingled facility, there is a chance of nuclear escalation. That is why the impact of Russia’s posture on China—as it pertains to its own hypersonic glide vehicles and tactical nuclear weapons—is so critical.

To this end, further exploration of the concept of ‘rapid response’ (快速反) should be part and parcel of understanding this postural evolution in China. Although Zhao Tong has noted in previous publications that this term could be associated with launch-on-warning, there are indicators that it could just as easily be referring to prompt global strike capabilities. The concept of ‘rapid response’ appeared in roughly a quarter of the Chinese texts surveyed for this section. In most cases, it was paired with near space, space-based weapons and prompt global strike capabilities.

As just one example, in China’s 2015 Military White Paper, rapid response appears on a list that contains ‘strategic warning’ (), ‘command and control’ (控制), ‘missile penetration’ (导弹突防) and ‘survivability protection’ (生存 ).22 While its inclusion on a list with ‘strategic warning’ could point towards launch-on-warning, the positioning of ‘rapid response’ between ‘missile penetration’ and ‘survivability protection’—combined with the importance of early warning in countering prompt global strike—suggest that this reference could also be applied to hypersonic glide vehicles, space planes and the future of strategic stability.

At the military level in China, US space planes such as the X-37B and X-51 are also frequently paired with discussions of ‘rapid response’ (快速反) and ‘rapid strike’ (快速打). While the latter term correlates with prompt strike systems as a direct translation to Chinese, the postural implication of ‘rapid response’ is less clear. In Chinese texts, prompt global systems, such as near space aircraft, are viewed as providing platforms for reconnaissance, missile defence, electromagnetic countermeasures, transportation, communication and space weapons.

For example, ‘rapid response’ appears in Harbin Institute of Technology theses to describe the use of near space aircraft as space weapon platforms and serves as part of a longer list that includes such capabilities as long-range attack, widerange, high-mobility, precision-strike capabilities or, in other words, the ‘fifth dimension’ (五位一体) of joint operations.

Chinese technical studies on hypersonic glide vehicles and related technologies emulate what they call US ‘rapid response’ programmes, such as the Defence Advanced Research Projects Agency (DARPA) Falcon project, with its the common aero vehicle and affordable rapid response missile demonstrator. While the USA and other foreign powers such as Russia dominate these Chinese studies, they also focus on China’s own ambitions when it comes to hypersonic glide vehicles and related systems.

Beyond papers advocating that China develop more active prompt global systems, a number also detail China’s own eforts to obtain ‘rapid response’ capabilities. These include: (a) hypersonic aircraft ground tests and wind tunnel tests by China North Industries Corporation; (b) a robust adaptive approach to near space vehicles based on trajectory linearization control at Nanjing University of Aeronautics and Astronautics; and (c) designs and simulations using terminal guidance laws, gas thermo-elastic multi-field coupling and thermal protection for reusable hypersonic vehicles at the Harbin Institute of Technology.

If the postural interpretation of the term ‘rapid response’ is retaliatory and supports ‘active defence’ (极防御), a case could be made that it diminishes the chances of pre-emption on the part of China. However, the larger question becomes: to what are these systems responding? If China’s hypersonic glide vehicles are to be deployed regionally to serve as A2AD systems mounted on the DF-21D or the DF-26 but with greater delegation of launch authority, this indicates a conventional payload and pre-emptive use.

However, if the goal of China’s hypersonic glide systems is more in line with that of Russia and targeted on defeating US missile defences, this suggests a nuclear payload. This latter trend could alter not only how ‘rapid response’ and ‘active defence’ are defined, but also how experts interpret China’s postural bedrock of no first use. This bedrock is being eroded by the very systems identified in the US Nuclear Posture Review as the USA’s deterrent against China and Russia—missile defence and prompt global strike.



Given that hypersonic glide tests conducted by China, Russia and the USA have not yet led to deployment, there is still an opportunity for greater analysis of how these technologies will affect the postural evolution of these three countries. Not taking the time to assess the potential outcomes of a technology-driven posture could lead to greater strategic instability and arms racing. As part of this process, beyond the US–Chinese paradigm, more emphasis needs to be placed on integrating Russia into analyses of China’s hypersonic glide vehicle development. This would provide a more nuanced analysis than the current bilateral calculations, which often simplify nuclear relations.

Chinese and US experts already meet on strategic nuclear issues at the academic and semi-official levels, although prompt global strike is generally a smaller and newer portion of the agenda. Expansion to a trilateral discussion that includes China, Russia and the USA at a more official level would mean moving beyond the idea that China’s asymmetrical disadvantage in nuclear warhead numbers precludes its involvement in US–Russian strategic stability talks. As China’s advances in hypersonic glide vehicle technology grow and its arsenal size responds to missile defence expansion in the Asia-Pacific region, the excuse of asymmetric disadvantage diminishes and the argument for trilateral engagement grows.


Dr Lora Saalman is the Director of and a Senior Researcher in the SIPRI China and Global Security Programme.