The withdrawal of USA and Russia from the Intermediate-Range Nuclear Forces (INF) Treaty in February 2019, spurred fresh arms development. Meanwhile, in December 2019, Russia announced that it had deployed its first hypersonic nuclear-capable missiles. President Putin described the Avangard hypersonic glide vehicle, which can fly at 27 times the speed of sound, as a technological breakthrough comparable to the 1957 Soviet launch of the first satellite. He said that the new generation weapon could hit almost any point on earth and could evade the U.S. missile shield. The Avangard, which is launched atop an intercontinental ballistic missile (ICBM), but unlike a regular missile which follows a predictable path after separation, This can make sharp manoeuvres enroute to its target, making it harder to intercept. “It heads to target like a meteorite, like a fireball,” he said. Avangard reportedly uses new composite materials to withstand temperatures of up to 2,000o C which may be reached at hypersonic speeds, and can carry a two-megaton nuclear warhead. Earlier in December 2018, the Avangard was launched from the Dombarovskiy missile base in the Urals and hit a practice target 6,000km away.
China has tested its own hypersonic glide vehicle. It displayed Dong Feng 17 (DF-17), at the 70th anniversary military parade. U.S. officials have talked about putting a layer of sensors in satellites to detect the hypersonic weapons earlier. Russia and China lead in hypersonic weapon development, trailed by the United States, France, India, and Australia who are known also 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, that could affect a missile’s sensitive inner electronics which need protection without adding extra weight or drag. Normally scramjet (supersonic combustion ramjet) are used in which combustion takes place even in supersonic airflow. 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 3 August 2018. The competition between China, Russia, and the U.S. fielding hypersonic weapons deployable from land, sea and air, and be able to perform multiple missions, has become vital to national security. Simultaneously counter-hypersonic solutions designed to stop enemy hypersonic weapons.
The Need for Speed
The speed and altitude at which hypersonic vehicles fly significantly challenge an adversary’s ability to detect, track, target and engage. Both are key for aiding access to hostile environments, which improves the effectiveness of even conventional weapon systems. This kind of velocity allows to reach fleeting targets well before they get away. Guiding a hypersonic vehicle to its target is challenging. Their manoeuvrability allows them to change course up to the last minutes of flight, and achieve a high degree of targeting precision.
Hypersonic Weapon Mechanics
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 technology uses a booster to reach cruising speeds. The scramjet engine is designed to compress the high-velocity, incoming air before combustion. This ‘air breathing’ technology renders a highly efficient engine at hypersonic speeds. Hypersonic cruise missiles which are powered by scramjet are restricted below 100,000 feet; hypersonic glide vehicles can travel higher. Some systems like Wave-rider use a first stage rocket to boost a body into the hypersonic regime. Other systems use scramjets after their initial boost, in which the speed of the air passing through the scramjet remains supersonic.
U.S. Hypersonic Weapon Approach
There are over a dozen US hypersonic projects. Also many private players like Raytheon are developing hypersonic systems. The focus of US DoD is on air-breathing boost-glide hypersonic systems. USA is also developing ceramics to handle the temperatures of hypersonic systems. The US anticipates having hypersonic weapons in the 2020s, hypersonic drones by the 2030s and recoverable hypersonic drone aircraft by the 2040s.
Disruptive Technology – Fast and Furiously Accurate
‘One mile per second’ is the hypersonic regime where lies the future. Whether it is hypersonic cruise missiles (HCMs) using rockets or scramjets to provide propulsion during flight, or the hypersonic boost–glide vehicles which travel into the upper atmosphere, and then hypersonic glide vehicles (HGVs) coast extraordinarily fast through the thin upper atmosphere. 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 maneuver 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 maneuverability of cruise missiles, hypersonic weapons are a disruptive technology capable of striking in short time.
Major Developments in Hypersonic Weapons
Russia has become the first to field an operational hypersonic weapon. They had unveiled six new ‘invincible’ weapons in March 2018. Russia has successfully tested the air-to-ground hypersonic missile Kinzhal (“dagger”) multiple times with the MiG-31 fighter and is now mounting the Kinzhal on the Tu-22M3 strategic bomber. Russia has completed the fifth test of the ship-based hypersonic Tsirkon (“zircon”) missile, which reaches a top speed of Mach 8, and can threaten land and sea based platforms. In December 2018, Russia successful tested Avangard HGV at Mach 20. Russia plans to arm the glider with nuclear warheads and deploy it on at least two different types of ballistic missiles (including the RS-28 Sarmat ICBM) sometime in 2020.
In 2016 China conducted at least seven tests of the DF-ZF glider at Mach 10, and range of 2,000 kilometers. In November 2017, the People’s Liberation Army Rocket Force completed two tests of the new DF-17 medium-range ballistic missile equipped with an HGV up to a range of 2,500 km. This vehicle may become operational in 2020. 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.
Russia and India are collaborating on the hypersonic BrahMos II anti-ship cruise missile. In February 2019, France became the first European nation seeking hypersonic weapons and announced Project V-MaX (experimental maneuvering vehicle), hoping to acquire a Mach 5 HGV by 2021. More nations are likely to pursue HCM and HGV capabilities.
Hypersonic Weapons Approach
Russia and China appear to be focused primarily on the delivery of nuclear warheads, and in which case, accuracy doesn’t really matter very much. 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. U.S. boost-glide weapon R&D program, the Advanced Hypersonic Weapon, has seen a glider tested over about 4,000 kilometers. Even the Russian Avangard may later have non-nuclear warheads after redefining accuracy. DARPA and Lockheed Martin are developing the hypersonic air-breathing weapon concept (HAWC) and tactical boost-glide (TBG) programs for the U.S. Air Force. U.S. Navy plans to develop and field an offensive hypersonic weapons by 2025. Submarines offer a great platform for adapting new missile technologies, like they did in the past for Tomahawk cruise missile or Trident II D5 ballistic missile. A Mach 5 HCM could hit a target 500 nautical miles away in 15 minutes or less, compared with as much as two hours for a subsonic cruise missile like Tomahawk. This would provide a prompt theater strike capability.
India’s Hypersonic Technology Demonstrator Vehicle
The HSTDV is 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 June 12, 2019, the HSTDV was tested with the scramjet engine. The test was a partial successful.
Upsetting the Status Quo
The initial high costs of the new hypersonic weapons may restrict them to nuclear warheads. The nuclear-armed boost-glide vehicles are unlikely to change the status quo much, as nuclear deterrence is already somewhat in place. The non-nuclear warheads, would present a new and potentially very significant security threat. Such weapons would threaten, a variety of targets at very short timelines and be difficult to defend. The kinetic speed will create a significant damage even with a small sized warhead.
Defence Against Hypersonic Weapons
It’s often claimed that it’s impossible to defend against hypersonic weapons because they are too fast. One cannot not accept a defenseless stance despite the inherent difficulties of defending against their speed and maneuverability. 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 U.S. 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.
Some security analysts believe a space sensor layer is the key to meeting the hypersonic threat. To mitigate this problem the United States is currently working on the development of 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 Russia and China are working on a new generation of over-the-horizon (OTH) radars. These may detect hypersonic missiles thousands of kilometers away. The new Russian Konteyner OTH radar and Chinese J27-A OTH 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.
The ‘point defence’ systems like the U.S. Patriot and Terminal High-Altitude Area Defense (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. But ballistic missiles do not have ability for manoeuvre that hypersonic missiles have. So, speed in itself, may not be a barrier for missile defence. For a variety of technical reasons, using these SAMs as ‘area defence weapons’ against hypersonic weapons would be impossible. Russia is developing the S-500 missile interceptor system, and the United States is working on the THAAD-ER (Terminal High Altitude Area Defence-Extended Range) system. Both these systems have been 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. The counter-countermeasures to hypersonic systems have only very recently got attention and US$ 157.4 million was allocated in the FY2020 Pentagon budget for hypersonic defence, out of $2.6 billion for all hypersonic-related research.
A Hypersonic Treaty?
The destabilizing effect of hypersonic weapons will pose a challenge for arms control. Beyond the United States, Russia and China, regional powers will seek to acquire hypersonic capabilities because they feel threatened by neighbours. There would be need to reduce ambiguities. The weaponisation of hypersonic technologies requires sophisticated facilities that would be cost-prohibitive for many nations. But this could change in the future. A complete ban on the diffusion of hypersonic technologies could be impractical, but some degree of export control could work well to minimise proliferation. A major problem in this regard is that hypersonic technologies have dual use potential. 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. In the longer term, a ‘hypersonic treaty’ could set numerical limits on the deployment of conventional and nuclear hypersonic missiles.
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 was a late entrant to the game of nuclear deterrence, but now has a robust survivable nuclear triad with long-range ballistic missiles, Multiple Re-entry Launch Vehicles (MIRV), air and sea based nuclear vector, a ballistic missile defence program, and an elaborate command and control mechanism. Rapid transformation in disruptive technologies like Artificial intelligence, cyber weapons, hypersonic weapons and persistent surveillance is already threatening to change the Status Quo in place by nuclear deterrence. Nuclear delivery platforms are difficult to hide. 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. As the traditional arms control weakens with the breakdown of the INF agreement, there is need to anticipate full-fledged weapon development in the coming decades. The bottom line is that hypersonic weapons will determine who is ‘precise and ‘prompt’ enough in 21st-century conflict. India has to quickly get onboard and start developing the ‘disruptive technologies’ and also invest in counter-capabilities. Even in the conventional domain, these technologies will provide a significant advantage. Military disadvantage and technological incapacity invariably leads to a countries marginalisation in international diplomacy.
This article was published in SP’s Aviation. Image credit to National Interest