DF-27 is a derivative of the DF-26 IRBM

India has to quickly get going and developing this ‘disruptive technology’ and also invest in counter-capabilities

by Air Marshal Anil Chopra (Retd)

The US Justice and Defence departments are reportedly investigating the leak of hundreds of US intelligence documents, including China’s military technology progress. As per the 28 February 2023, top-secret report by the Joint Chiefs of Staff intelligence directorate, China’s People’s Liberation Army (PLA) had mid-February this year successfully tested the new long-range DF-27 hypersonic intermediate-range ballistic missile (IRBM). The missile could probably evade US ballistic missile defences. China could now quickly strike up to nearly 8,000 kilometres. That could mean hitting targets well beyond the South China Sea (SCS) and farther than the second island chain. It could also mean all targets in India and beyond. The variants of the new missile could attack land targets and ships.

During the test, the IRBM flew for 12 minutes and travelled 2,100 kilometres. According to earlier reports, the DF-27 has a range of 5,000 to 8,000 kilometres. The manoeuvrable hypersonic weapon could evade air defences. It has the potential of being a “carrier killer”. The missile could be handy to keep friends of Taiwan at long distances while invading to annex the Island nation. Russia and China lead in hypersonic weapon development, trailed by the United States, France, India, and Australia, also known to be pursuing the technology.

What Is Hypersonic?

Hypersonic is a flight through the atmosphere at speeds in excess of Mach 5. At this speed dissociation of air begins to become significant and high heat loads get generated, which could affect a missile’s sensitive inner electronics which need protection without adding extra weight or drag. Hypersonic weapons fall into two categories: boost-glide and scramjet. In a boost-glide system, a rocket accelerates its payload to high speeds. The payload then separates from the rocket and glides unpowered to its destination. Scramjet (supersonic combustion ramjet) technology uses a booster to reach cruising speeds. Scramjets allow combustion even in supersonic airflow. The scramjet-powered air-breathing hypersonic cruise missiles (HCM) are restricted below 1,00,000 feet. Hypersonic glide vehicles (HGV) can travel higher. The Boeing X-51 Wave-rider flew on scramjet for 210 seconds in 2013, finally reaching Mach 5.1 on its fourth flight test. A wave-rider is a hypersonic aircraft design that improves its supersonic lift-to-drag ratio by using the shockwave being generated by its own flight as a lifting surface, a phenomenon known as compressive lift. China’s XingKong-2, also a wave-rider, had its first flight in August 2018.

Russia First To Use Hypersonic Weapons In Combat

Russia’s nuclear-capable hypersonic missiles have been operational since December 2019. Russia has claimed to have fired nine hypersonic missiles, with conventional warheads, at major armament storage facilities and command and control centres in Ukraine. The Avangard HGV, is launched atop an intercontinental ballistic missile (ICBM). After separation it can reportedly fly at 27 times the speed of sound, and make sharp manoeuvres enroute to its target, making it harder to intercept. Avangard reportedly uses new composite materials to withstand temperatures of up to 2,000 deg C which may be reached at hypersonic speeds, and can carry a two-megaton nuclear warhead. Russia’s HCM Kinzhal (“dagger”) is mounted on the MiG-31 fighter and the Tu-22M3 strategic bomber. The ship-based hypersonic Tsirkon (“zircon”) missile, reaches a top speed of Mach 8, and can threaten land and sea based platforms.

China’s Dong Feng DF-17

The DF-17 is a solid-fuelled road-mobile medium-range ballistic missile specifically designed to mount the DF-ZF HGV. The DF-ZF glides at Mach 10, and range of 2,500 kilometres, and was first unveiled on 1 October 2019, making this China’s first operational hypersonic weapon systems and one of the world’s first to be put in full initial operation. These are operational with the People’s Liberation Army Rocket Force (PLARF). In August 2018, China tested the Starry Sky-2, using experimental hypersonic wave-rider technology and reached speeds of Mach 5.5 for 400 seconds. China’s DF-26 ballistic missile is colloquially called the “Guam killer”. With DF-27, the range has got further increased. Additionally, China also possesses the HGV equipped DF-41 intercontinental ballistic missile with more than 14,000 kilometres range. They also have the YJ-21 anti-ship hypersonic missile can threaten aircraft carriers.

US Hypersonic Weapon Approach

There are over a dozen US hypersonic projects. Also many private players like Raytheon and Lockheed Martin are developing hypersonic systems. The focus of USA is on air-breathing boost-glide hypersonic systems. USA is also developing ceramics to handle the temperatures of hypersonic systems. The US Department of Defence (DoD) has spent more than $8 billion since 2019 on hypersonic programs. In its latest five-year budget plan, DoD has requested $13 billion over the 2023–2027 period for developing hypersonic missiles and almost $2 billion for procuring missiles. The US DoD wrapped up one of its hypersonic weapons programs, the Hypersonic Air-Breathing Weapon Concept (HAWC), with a successful final flight test in January 2023. It was a Lockheed Martin-designed missile, launched from a B-52 bomber and flew at speeds greater than Mach 5 and for more than 300 nautical miles. The US anticipates having hypersonic weapons by 2024, hypersonic drones by the 2030s and recoverable hypersonic drone aircraft by the 2040s.

India’s HSTDV And Indo-Russian BrahMos-II

The Hypersonic Technology Demonstrator Vehicle (HSTDV) is India’s Defence Research and Development Organisation’s (DRDO) scramjet demonstrator for hypersonic cruise missile. The eventual target is to reach Mach 6.5 at an altitude of 32.5 km. A 1:16 scale model of the vehicle was tested at a hypersonic wind tunnel operated by Israel Aerospace Industries. The isolated intake has been tested at a trisonic wind tunnel at India’s National Aerospace Laboratory (NAL) in Bangalore. The scramjet engine has been tested in the lab twice for 20s. On 12 June 2019, it was tested at Integrated Test Range (ITR) at the Abdul Kalam Island in the Balasore, Odisha. The test was a partial success. HSTDV cruise vehicle was mounted atop a solid booster stage. At 30 km altitude payload fairing separated, followed by separation of HSTDV cruise vehicle, air-intake opening, fuel injection and auto-ignition. After sustaining hypersonic combustion for 20 seconds, cruise vehicle achieved velocity of nearly 2 km per second. This test flight validated aerodynamic configuration of vehicle, ignition and sustained combustion of scramjet engine at hypersonic flow, separation mechanisms and characterised thermo-structural materials. The HSTDV is set to serve as the building block for next-generation hypersonic cruise missiles.

Russia and India are collaborating on the hypersonic BrahMos-II HCM. It is estimated to have a range of 600 km and a speed of Mach 8. Making it the fastest HCM in the world. Development could take 6–8 years to complete.

Disruptive Technology: Fast And Furiously Accurate

‘One mile per second’ is rather fast and gives very high kinetic energy which is a function of the square of velocity. A one-kilogram object delivered precisely at such high speed can be more destructive than one-kilogram of TNT. The low-altitude path helps mask HCMs, making invisible to early warning radars. HGVs can manoeuvre during flight, and so more difficult to intercept, even if detected. By offering the precision of near-zero-miss weapons, the speed of ballistic missiles, and the manoeuvrability of cruise missiles, hypersonic weapons are a disruptive technology capable of striking in short time.

Weapon Employment Approach

Russia and China initially appear to be focused primarily on the delivery of nuclear warheads, and in which case, accuracy doesn’t really matter very much. Yet Russia has used it with conventional warheads in Ukraine. The United States is more interested in the delivery of non-nuclear warheads, and therefore, accuracy (few meters) is absolutely critical for the weapon to be militarily effective. Both aircraft and submarines offer a great platform for adapting new missile technologies, for a prompt theatre strike capability.

Hypersonic Trajectory And Counters

The speed and altitude at which hypersonic vehicles fly, significantly challenge an adversary’s ability to detect, track, target and engage. High velocity allows to reach fleeting targets well before they get away. Their manoeuvrability allows them to change course up to the last minutes of flight, and achieve a high degree of targeting precision.

Ballistic missiles fly at much higher altitudes and follow relatively predictable trajectories. Mostly, it is possible to predict the destination of any given ballistic missile payload by using space-based and ground-based early-warning systems. Powerful radar, like the US Pave Paws or the Russian Voronezh radars, combined with space-based sensors can track a ballistic missile with a range of about 3,000 km, resulting in about 14 minutes of tactical warning.

A RAND study suggests that the detection for HGV would be only six minutes prior to impact. Even if detected by a ground-based radar, there will be a high degree of uncertainty about their destinations. This makes hypersonic missiles suitable for surprise long-range strikes. They will penetrate even the most advanced air defence systems. But one cannot not accept a defenceless stance despite the inherent difficulties of defending against hypersonic weapons speed and manoeuvrability.

Chinas Deploys Hypersonic IRBM DF27 Implications And Choices For India

Counter-hypersonic solutions designed to stop enemy hypersonic weapons are evolving. The United States is currently working on developing a new satellite-sensor layer, which presumably would be positioned in low earth orbit (LEO), in order to provide continuous tracking of both ballistic missiles and hypersonic vehicles. It will require a constellation of hundreds of satellites. More advanced sensors are expected to be placed into space. Meanwhile new generation of over-the-horizon (OTH) radars like the Russian Konteyner radar and Chinese J27-A are likely to detect hypersonic missiles 3,000 km away. Delayed detection, and a degraded decision-making environment may have consequences for threat perceptions, and accidental escalation.

Due to their speed, an envelope of ionized gas forms around the glide vehicle in atmosphere, making base-to-vehicle communication impossible. This cloud of ionized gas is easy for satellites to detect and track. Furthermore, the heat generated at those velocities renders external sensors inoperable and necessitates the detachment of HGVs from their carrier ballistic missiles at the upper limits of the atmosphere to avoid their burning up. Thus there are issues that the defender can exploit.

The ‘point defence’ systems like the US Patriot and Terminal High-Altitude Area Defence (THAAD), and Israeli David Sling and Iron Dome, and Russian S-400 can defend small areas against ballistic missiles, which are actually moving faster than hypersonic weapons. For a variety of technical reasons, using these SAMs as ‘area defence weapons’ against hypersonic weapons would be impractical. Russia’s S-500 missile interceptor system, and the United States’ THAAD-ER (Terminal High Altitude Area Defence-Extended Range) systems are conceived for area defence. It would be cost-prohibitive to deploy them to protect all possible targets. It could be realistic to use them to protect critical facilities like command and control nodes and land-based nuclear assets, mitigating first strike vulnerability fears.

Another way of defending against hypersonic weapons (as well as other types of missile) could be through directed-energy systems, in particular, laser weapons. However, the effectiveness of laser weapons against hypersonic missiles is yet to be seen and the probability is difficult to assess due to the technology being at an early stage of development.

Destabilisation Effects

As more and more countries acquire hypersonic weapons destabilizing effect of hypersonic weapons will pose a challenge for arms control. The weaponisation of hypersonic technologies requires sophisticated facilities that would be cost-prohibitive for many nations. But this could change in the future. Hypersonic technologies have dual use potential, and so cannot be banned. Establishing ‘Hot-line’ communication might reduce the risk of misinterpretation. Assurances that early-warning radars and satellite will not be targeted, may help. However, without a reliable verification mechanism for clarifying the nature of the warheads carried by hypersonic missiles, warhead ambiguity is likely to continue.

Way Ahead India

Many consider conventional hypersonic weapons or strategic non-nuclear high precision weapons to be equivalent to nuclear weapons in terms of their implications for deterrence. There is a need to worry about the potential combination of high-precision warhead delivery methods with low-yield nuclear warheads. Such weapons would be ‘tactically usable’.

India has a robust survivable nuclear triad with long-range ballistic missiles, Multiple Re-entry Launch Vehicles (MIRV), air and sea based nuclear vectors, a ballistic missile defence program, and an elaborate command and control mechanism. Today it is possible to launch precision strikes on the nuclear command, communication and critical infrastructure networks, disrupting an adversary’s nuclear decision-making chains or targeting nuclear assets. China is continuing the nuclear weapons modernization and expansion program by fielding more types and greater numbers of nuclear weapons. They plan to go up from current 250 to 1,000 warheads by 2030.

DF-27 gives PLA greater precision strike options both with nuclear and conventional warheads. It also impacts deterrence. Hypersonic weapons would avoid existing missile defence systems, either by continually manoeuvring or by flying at lower altitudes to reduce warning time.

The bottom line is that hypersonic weapons will determine who is ‘precise and ‘prompt’ enough in 21st-century conflict. With credible Indian hypersonic weapons capability, the PLA Navy’s large ships and aircraft carriers can be kept further away from Indian shores. Hypersonic weapons could be used to target PLA’s large weapon storage areas and also main command and control centres in garrisons in Tibet and Xinjiang. India has to quickly get going and developing this ‘disruptive technology’ and also invest in counter-capabilities. Important Indian targets like in NCR region and other strategic and command and control sites would have to have robust air defence systems including those using Directed Energy Weapons (DEW). Modern hypervelocity guns and rail-guns could also be used.

Hypersonic weapons even in the conventional domain will provide a significant advantage. Fielding hypersonic weapons deployable from land, sea and air, and be able to perform multiple missions, has become vital to national security. Military disadvantage and technological incapacity invariably leads to a country’s marginalisation in international diplomacy. India has to move with a sense of urgency on both operationalizing hypersonic technology and counters to it, lest it gets left too far behind. India needs to hasten indigenous hypersonic technology development and also accelerate the BrahMos-II program, and simultaneously evolve deployable directed-energy air defence weapons.

The writer is Director General, Centre for Air Power Studies. Views expressed are personal