By Michael Fabey / Janes / Feb 17, 2023

US Navy (USN) Secretary Carlos Del Toro has made it clear that putting hypersonic capabilities onto fleet assets ranks at the top of his immediate to-do list.

“I’m going to put as much resources, as much tension, and as much intellectual capacity in my management team – and work as closely with industry as we can – to make that a priority and a reality,” Del Toro told reporters on 11 January during a break at the Surface Navy Association (SNA) 2023 annual symposium.

He and the navy are “completely focused” on getting the weapons on the guided-missile destroyer USS Zumwalt in 2024 as planned, Del Toro added.

The USN is leveraging previous research efforts while trying to accelerate technology developments to integrate hypersonic weapon systems with current platforms to better prepare US forces for current threats.

“Hypersonic missiles are considered a possible counter to the anti-access and area-denial (A2/AD) systems that potential near-peer adversaries such as China and Russia are deploying to prevent US forces from operating freely in their regions,” the US Congressional Budget Office (CBO) said in its report US Hypersonic Weapons and Alternatives, released on 31 January.

“In theory, hypersonic weapons could be launched from outside the range of those systems and could reach targets within minutes over medium-to-intermediate ranges (from hundreds to a few thousands of km), with a high degree of accuracy and less vulnerability to defences than existing missile,” the CBO reported.

The CBO found hypersonic missiles with sufficient ranges for A2/AD scenarios – at least 1,000 km, or about 600 mile, for missiles launched from aircraft and at least 3,000 km, or about 1,900 mile, for missiles launched from the ground or sea – have the speed to be useful in the early stages of a conflict with a near-peer adversary.

The CBO estimates that hypersonic missiles would cost roughly one-third more than ballistic missiles with manoeuvrable warheads that had the same range and accuracy and travelled at similar speeds.

“Given their cost, hypersonic weapons would provide a niche capability, mainly useful to address threats that were both well-defended and extremely time-sensitive (requiring a strike in 15 minutes to 30 minutes),” the CBO reported. “If time was not a concern, much cheaper cruise missiles could be used. If targets were time-sensitive but were not protected by defences that effectively intercept incoming ballistic missiles in the middle of their flight, less costly ballistic missiles with manoeuvrable warheads could be used.”

However, hypersonic missiles with those ranges would be more expensive than similar ballistic missiles and pose much greater technical challenges, the CBO reported.

“Offensive and defensive hypersonic weapons will give our navy the edge it needs to maintain naval superiority against our adversaries,” Dale Sisson Jr, technical director for the Naval Surface Warfare Center Dahlgren Division (NSWCDD), told Janes.

“Our goal at the Naval Surface Warfare Center Dahlgren Division is to establish Dahlgren as the Surface Navy Lead for offensive and defensive hypersonic weapon systems integration. We’re looking to evolve our test and development assets into national hypersonic assets.”

It’s not a different category of weapons – just a difference in the speed of the projectile the guns or launchers fire, Sisson said.

Dahlgren, which has been operating since 1918, has an established history of hypersonic work, he noted.

In 1950, Dahlgren developed the first six-degrees-of-freedom trajectory simulation, a breakthrough that enabled the successful development and deployment of guided ballistic missiles, Sisson said. In the early 1970s, Dahlgren engineered an 8 inch (20.3 cm) gun-launched ramjet that could achieve a near-hypersonic, Mach 4 velocity.

In recent years, Dahlgren has modelled, designed, prototyped, and flown the navy’s hypervelocity projectile, which is a guided round capable of hypersonic velocities when launched from high-speed guns, Sisson pointed out. In the 1990s, Dahlgren contributed expertise with materials, design, and systems engineering to support an accurate demonstration flight of the Lightweight Exoatmospheric Projectile.

“Since 2016, the NSWCDD has conducted integrated air and missile defence analyses focused on hypersonic missiles,” he said.

“We are working the challenges of hypersonic flight and weapon systems integration,” Sisson said. “We will lead the development and fielding of naval defensive and offensive hypersonic systems. As far as the future goes, we expect to become more and more involved in both the offensive and the defensive weapons that this nation is assembling and building up to counter threats around the world right now”.

Dahlgren is involved in getting Zumwalt ready for the transition to hypersonics. “We are currently testing the capabilities of hypersonic weapons. We conduct engagement modelling and mission-level modelling of the trajectories of hypersonic vehicles using system-level tools to ensure the warfighting utility of these new weapons. We bring specialised modelling, simulation, and ground testing capabilities to assess the lethality and effectiveness of weapon systems used in hypersonic engagements,” Sisson said.

“It’s a lot of the same function, whether it’s hypersonic weapons or supersonic weapons,” he said. “From fire control to the fire-control loop, that’s where we come in. We have a hypersonics test facility. We can test in a controlled environment how hypersonics perform.”

“We have a hypersonics test facility with a couple [of] different components that provide the capability we’re building at Dahlgren to support hypersonics research and development in a variety of facets,” Sisson said.

“We can set up a ‘hardware-in-the-loop’ capability, enabling us to look at projectiles and missiles, test them, and explore how they respond to various conditions. We have an outdoor range with a hypersonic launcher that allows us to launch projectiles up to 2.5 km a second. We can support over-ocean tests taking radar and other sensors to where needed via boat,” he said.

“Leveraging existing technical expertise is absolutely critical. Hypersonic projectiles are certainly a new application, but not necessarily new technology. A large workforce worked on the electromagnetic railgun test and development for a number of years. We have now pivoted a significant number of personnel to work on hypervelocity projectiles,” Sisson added.

“The proposed mission for the electromagnetic railgun morphed tremendously over time,” he acknowledged, creating a “high-powered Swiss Army knife” of a weapon.

The navy decided that the railgun is not going to be fielded in the short term, but Dahlgren has not “100% curtailed our efforts”, Sisson said.

That kind of basic electromagnetic launching technology is easily transferable to the development of hypersonic weapons. It’s the same kind of core technology, for example, used for the new aircraft carrier electromagnetic launching system, he added.

“The railgun utilises a lot more power than what we’re seeing on the front end of the launch of an aircraft,” Sisson said. That kind of technology enables the delivery of multiple rounds per minute and high-Mach speeds and long range.

“You don’t have energetics in that launch process. You may have energetics in your round depending on the application and how you want to use them, but to chase that projectile down the barrel, there are no energetics in that equation. There’s nothing to ‘produce’, no supply chain – just power. If you’ve got power and a big enough plug, you can do some amazing things,” Sisson added.

Comment

While the development of hypersonic weapons continues full throttle, government and industry have been working, sometimes in tandem, to increase its range. One such company is Helicon Chemicals, which has created a new kind of ‘binder’ used for rocket propellant that CEO Wes Naylor says should work for airbreathing hypersonics.

The propellant replaces the rubber binder, which can produce an inefficient uneven burn when ignited the aluminium energetic in the rocket, with a new chemically created metallic polymer composite. The new propellant burns evenly and more efficiently with the aluminium – thus providing greater range, Naylor added.

This kind of technology would make it possible to increase a missile’s range at the subassembly level by removing the rocket motor, taking out the current propellant, replacing it, and then replacing the motor. No re-engineering is required, Naylor noted.