The development of hypersonic weapons is now at the forefront of international strategic concerns. In Ukraine, Russia used the Kh-47M2 Kinzhal missile operationally for the first time, demonstrating the practical strike capability of these weapons, though several were intercepted by Ukrainian Patriot systems. Beyond Europe, rising tensions around the Taiwan Strait and significant U.S. investment point to a high-speed technological arms race.
Hypersonic weapons: what are we talking about?
Hypersonic weapons are characterized by their ability to travel at speeds exceeding Mach 5, over 3 728 miles per hour (6,000 kilometers per hour), while remaining within the Earth’s atmosphere. This dual characteristic, extreme speed and maneuverable trajectory, calls into question the effectiveness of traditional missile defense systems. According to models from the Defense Advanced Research Projects Agency (DARPA), the likelihood of intercepting these missiles would be less than 10%.
To understand hypersonics, we must first abandon conventional ballistic logic. While conventional missiles follow a predictable parabolic trajectory outside the atmosphere, hypersonic weapons operate in the upper atmosphere, between 12 and 37 miles (between 20 and 60 kilometers) above sea level and can maneuver within it.
Hypersonic weapons fall into two categories with distinct architectures :
– Hypersonic gliding vehicles (HGVs) are launched by an initial vector and then enter an unpowered gliding phase. During this phase, they use their aerodynamic lift to perform complex, unpredictable maneuvers. The Russian Avangard system, for example, can modify its lateral trajectory over a distance of up to 932 miles (1 500 kilometers) and reach speeds of up to Mach 20.
Hypersonic cruise missiles (HCMs) use a supersonic ramjet (scramjet) engine that enables continuous combustion in an ultra-compressed air stream. The Russian Zircon missile is one of the most advanced examples of this technology.
These weapons impose extreme technical constraints. Due to atmospheric friction, their structures must withstand temperatures in excess of 3 632°F (2 000°C). Guidance becomes complex in a plasma-saturated environment, as plasma interferes with radio signals.
Additionally, scramjets can only operate at very high speeds, necessitating conventional initial propulsion to reach the combustion threshold. Unlike conventional engines, scramjets have no moving parts, reducing weight and improving efficiency but imposing a minimum entry speed of around Mach 4. The trajectory of HGVs is said to be semi-ballistic. Initially propelled by a rocket, they continue with a high-speed glide phase, which renders any ballistic prediction inoperative.
Hypersonic weapons : a new arms race
Geopolitically speaking, three powers are currently leading the hypersonic race. Russia has deployed several systems, including the Kinzhal air-to-ground missile, which reaches Mach 10 and has a range of 1 242 miles (2 000 kilometers); the Zircon naval missile; and the Avangard strategic glider, which is capable of carrying a nuclear warhead.
China is heavily involved and continues to accelerate the development of several delivery systems. The DF-17, an HGV that has already been tested under operational conditions, completes a range that also includes the YJ-21 anti-ship missile.
The United States has been cautious in the past, but is now investing heavily to catch up. Programs such as the Hypersonic Air-breathing Weapon Concept (HAWC) and the Air-Launched Rapid Response Weapon (ARRW) have enabled more than a dozen tests to be carried out by 2024, marking a rapid increase in capabilities.
This dynamic is not only relevant to the major powers. Regional players are also actively involved. For example, Japan is developing the HVGP, a hypersonic glider scheduled for launch in 2026. It is capable of reaching Mach 5 over a range of 559 miles (900 kilometers).
Since 2023, France has been conducting trials with its V-MAX scramjet demonstrator. In cooperation with Russia, India is developing the BrahMos-II, a cruise missile capable of reaching Mach 7. North Korea is developing the Hwasong-16B, a modified ballistic missile designed to reach Mach 10.
Nuclear deterrence during the hypersonic weapons era
The emergence of these weapons reshuffles the cards of nuclear doctrines and regional balances. Their ability to carry nuclear warheads while drastically reducing warning times challenges the fundamental principles of deterrence. These devices have a low radar signature, sometimes less than 0.002 m², which makes them very difficult to detect. A surprise strike becomes technically possible, increasing the risk of escalation or strategic misunderstanding.
In the Asia-Pacific region, U.S. aircraft carriers are now exposed to threats that call into question their freedom of action. In Europe, positioning Kinzhal missiles in Belarus reduces NATO’s response time to just a few minutes. Worryingly, there is also a legal uncertainty: no international treaty specifically governs hypersonic weapons, which makes their development uncontrolled and their testing difficult to verify. The instability they generate is therefore not just hypothetical.
Increasingly complex interception
Current defense systems face a major challenge in intercepting hypersonic missiles. While ballistic missiles follow a predictable parabolic trajectory outside the atmosphere, hypersonic missiles fly at medium altitudes between 30 and 60 kilometers and perform unpredictable maneuvers. These sudden course changes, made possible by aerodynamic bounces or tight turns, confuse interception systems.
Ballistic missiles can reach higher speeds up to Mach 20 upon reentry but they remain vulnerable because their trajectory is stable and visible. Hypersonic missiles, on the other hand, fly lower and flatter, which considerably limits the reaction time of ground-based radars. Their speed makes them more dangerous, and their low radar signature like that of the Avangard, which is equivalent to that of an insect complicates effective detection.
Systems such as THAAD or the S-400, which are designed to address ballistic threats, are unable to effectively cope with these new weapons. Endo-atmospheric interceptors, such as the Patriot, are limited to speeds below Mach 4 and lack the agility and power to effectively counter these new weapons. The heat generated by their speed, does not mask their infrared signature, as is sometimes believed. This leaves a narrow, yet exploitable, detection window.
Breakthrough solutions are being studied to meet these challenges. In the United States, the Glide Breaker project aims to disrupt the trajectory of gliding vehicles using plasma jets to create destabilizing pressure gradients. Directed-energy weapons, such as HELIOS lasers, could neutralize missiles by heating their surfaces from up to 12 miles (20 kilometers) away.
Additionally, new constellations of low-orbit satellites, such as the HBTSS system, offer ultra-precise infrared detection capabilities with a resolution of 0.15 kelvin and an announced detection rate close to 98%. These advances are supported by international cooperation within NATO and the AUKUS alliance, as well as technological partnerships between Japan and the United States.
Hypersonic weapons represent a significant technological advancement. Their speed, stealth, and maneuverability make them formidable instruments capable of redefining the balance of military power. However, their extremely high cost and the rapid development of countermeasures limit their strategic dominance for the time being.
