Sea

How will navies train for hypersonic weapons defence?

As the emergence of hypersonic weapons creates a new threat for naval vessels, sailors will need simulated targets that realistically represent them to practice against. Alex Love speaks to Melbourne-based Grollo Aerospace, which has developed a low-cost, supersonic training missile for the Royal Australian Navy.

As the emergence of hypersonic weapons creates a new threat for naval vessels, sailors will need simulated targets that realistically represent them to practice against. Alex Love speaks to Melbourne-based Grollo Aerospace, which has developed a low-cost, supersonic training missile for the Royal Australian Navy.

The emergence of hypersonic weapons has caused a global arms race. The US, Russia, and China all have technologies in development with the potential to travel at speeds far surpassing Mach 5.


There are two main types of hypersonic weapon. The first functions similarly to a self-propelled cruise missile. The second type is carried on a hypersonic glide vehicle (HGV) into Earth’s upper atmosphere where it detaches using gravity to achieve extreme speeds.


Russia has recently been testing its 3M22 Zircon hypersonic anti-ship cruise missile, which is claimed to achieve speeds faster than 6,090mph at Mach 8. The country has also been developing the Avangard hypersonic glide vehicle, which Russian President Vladimir Putin has declared can reach Mach 20 - although this not been verified independently.


In 2019, China unveiled its DF-17, a medium-range ballistic missile mounted to the DF-ZF HGV. Both are reportedly operational.


And in October 2020, the US announced successful trials of its hypersonic missile, known as the Common-Hypersonic Glide Body (C-HGB).


These developments have raised the question of how to defend against such a threat. As well as being fast, unpredictable and highly manoeuvrable, hypersonic weapons can also fly at varying altitudes and are difficult to detect.


“Hypersonic missiles like the Zircon, for example, do certainly represent an evolution of the challenge that was already posed by supersonic missiles like the P-800,” says Dr Sidharth Kaushal, research fellow for missile defence and sea power at the Royal United Services Institute for Defence and Security Studies (RUSI).


"The essential challenge remains the same, which is: how do you intercept missiles flying at sea-skimming levels for parts of their trajectory, which gives a crew very low warning times? And the hypersonic missile kind of exacerbates that problem further still.”

Overcoming hypersonic defence training challenges

Training to defend against hypersonic weapons presents considerable challenges. It is difficult to replicate their speed in real-world environments and there are significant costs involved. Other problems come from simulating their high levels of manoeuvrability and sudden changes in direction that cause unpredictable flight patterns.


The Royal Australian Navy has previously simulated attacks by flying aircraft towards naval vessels. However, the speeds were insufficient and the flight patterns did not accurately match a hypersonic threat. In addition, aircraft appearing on radar have a much larger profile than a hypersonic missile.


And while there are existing training systems available to combat hypersonic threats, they are costly. The GQM-163 Coyote from Orbital Dynamics, for instance, is a sea-skimming target missile used by the US Navy and allies. However, each training missile has a reported price tag of approximately $4m. Training with this system also predominantly takes place in Hawaii, presenting geographical obstacles for many navies.

EVADER has been designed to accurately imitate the sea-skimming trajectory and flight path of an anti-ship missile at supersonic speeds.

To address these issues, Australian company Grollo Aerospace has developed its EVADER hypersonic training missile. According to the company, EVADER is relatively low-cost for hypersonic training missiles at $250,000 per unit.


Made from stainless-steel and weighing around 90kg, the 4.2m-long EVADER features a ramjet engine and runs on standard JP1 jet fuel. It is controlled by an onboard autonomous targeting system.


Grollo Aerospace claims that the EVADER can be used at least ten times before it needs replacing. It has been designed to accurately imitate the sea-skimming trajectory and flight path of an anti-ship missile at supersonic speeds. And its manufacturers are confident the EVADER can achieve hypersonic speeds in future.


Development of the EVADER started around 2010 and was self-funded by Grollo Aerospace. In 2017, the company won a $1.75m contract from the Australian Government’s Defence Innovation Hub. In 2018, Grollo confirmed the missile design was viable during tests in Woomera. The company has now applied to the Defence Innovation Hub for a $2.85m contract to prove EVADER’s supersonic air target capabilities in an operations environment, as well as reliability in safety when simulating an attack from incoming missiles at high speeds.


After the next round of texting, it is hoped the EVADER will achieve technology readiness level 7 and edge closer to operational readiness. Results will be submitted to the Australian and US navies.


Although the Australian Government is not yet providing further funding for the EVADER development, defending against ballistic missiles is a priority.


“The proliferation of ballistic and very high-speed missiles means our deployed forces require enhanced deployable air and anti-missile defence when on operations,” says an Australian Department of Defence spokesperson. “In addition to investment in defensive systems, the government will continue to work closely with the United States on countering ballistic missile threats.”

// The GQM-163 Coyote is a sea-skimming training missile used by the US Navy to simulate the threat from hypersonic missiles. Credit: US Navy.

International collaboration on hypersonic defence

As hypersonic weapons may have the capability to carry nuclear warheads, failure to keep up with the increased speed risks nullifying the deterrent of a retaliatory strike. And at present, even the US military has no direct defence against hypersonic threats, but it is working on methods to shoot them down and has other counter measures such as cyberattacks.


Tracking a hypersonic missile typically requires an intricate network of sensors and assets, including UAVs, satellites and naval vessels. As a result, defending against hypersonic weapons is unlikely to be achieved by one nation alone. Therefore, international collaboration could be the best hope that many nations have of handling the threat.

EVADER could be developed further through partnerships between different nations, which could then bring down the costs and increase the regularity of training.

“It's simply not really possible, particularly for middle powers who are aligned with the US, to do every aspect of missile defence themselves,” Kaushal explains. “But what they can realistically do – and contribute in this way to a wider missile defence network held at alliance level – is deal with different aspects of the problem.”


“For example, the Grollo [system], because it reduces the costs of testing by a significant margin compared to the Coyote, could perhaps eventually be held across the alliance level at missile defence exercises carried out in the Pacific theatre and reduce the costs of those exercises by a significant margin, considering there are already significant costs to bringing this number of vessels and assets together.”


Kaushal also suggests that Grollo’s EVADER could be developed further through partnerships between different nations, which could then bring down the costs and increase the regularity of training.


“We've seen, in terms of US cooperation with Israel on missile defence, that kind of had a feedback effect for the US because the Israelis brought the costs of certain platforms down significantly,” he adds. “And that enabled the US to basically buy back some of the technology they've shared with the Israelis and the Israelis subsequently worked on, modified and reduced the costs. If the Grollo [system], for example, became an alliance-wide standard, I'd say that would have significant effects on how frequently and how cost-effective a manner live-fire exercises can be carried out.”

// Main image: Grollo is developing EVADER as a training system for the Royal Australian Navy. Credit: Royal Australian Navy