Australia’s 36-foot ‘Ghost Shark’ is just the first of the new, huge robot war submarines

Struggling to build and maintain its existing manned submarines, the US Navy is rushing to build a bunch of unmanned submarines. But the Australian navy might get there first – with its own robotic sub.

Australia’s Ghost Shark unmanned undersea vehicle is also a sort of stopgap that can buy time for the Royal Australian Navy to acquire larger manned subs under the auspices of the Australia-United Kingdom-United States undersea alliance, or Aukus.

The main problem for the Australians is that their Ghost Shark, though it is bigger than a city bus, is small for a submarine. Under the water, size confers endurance and firepower – two things the Ghost Shark will lack compared to the bigger robo-sub in development in the United States.

Right now, the US Navy only operates big, manned nuclear-powered submarines that can sail thousands of miles across the Pacific and Atlantic Oceans and linger for months in conflict zones. But nuclear subs are complex, expensive and maintenance-intensive.

So while the USN requires 66 nuclear attack submarines, it currently operates just 50 or so – and numbers are set to decline as shipyards grapple with a desperate labor shortage that has delayed the construction of new vessels.

A 377-foot Virginia-class attack sub costs $2 billion and, under the best conditions, takes 18 months to build. Lately, it’s taken shipbuilders three years or longer to finish a Virginia.

Robotic subs could help close the gap. Boeing has been developing the Orca, an 85-foot non-nuclear sub that can navigate autonomously as far as 6,500 miles. Fitted with sensors and weapons, an Orca could lay mines, sweep for mines and hunt enemy subs and surface ships – cheaply and at zero risk to human crews. An Orca costs around $100 million, and such big robo-subs are classed as Extra Large Unmanned Underwater Vehicles (XLUUVs).

But the Orca represents a new capability for the US fleet, and it’s not coming particularly fast. The first five prototypes finally began reaching the fleet in December, three years after the original deadline. The USN wants 50 or more operational Orcas, but it could take decades to acquire them all.

So it may have come as a shock to some American observers when, earlier this month, the Australian defense ministry announced the delivery of the first Ghost Shark UUV for the Royal Australian Navy – two years after the ministry inked a deal for the prototype vessel. That prototype cost $30 million; production versions should cost even less.

The Ghost Shark could performa many of the same missions the Orca performs. Better yet, the prototype arrived months early, and the defense ministry expects manufacturer Anduril Australia to deliver a production-standard version of the robo-sub by the end of next year.

“Ghost Shark is an exemplar of how [the] defence [ministry] and Australian industry can move at speed,” Minister for Defense Industry Pat Conroy said.

A flotilla of Ghost Sharks could fill a capability gap as the RAN moves – too slowly, some say – to replace its six 254-foot, non-nuclear Collins-class attack submarines first with second-hand American Virginias and, later, a new nuclear attack sub design combining American and British technology. The first of these Aukus submarines – the used Virginias – won’t reach the Australian fleet until the early 2030s.

But don’t expect too much from the Ghost Sharks. While any UUV is better than no UUV, the Ghost Shark might represent a middling capability. Photos the Australian defense ministry and Anduril Australia released seem to indicate the prototype is just 36 feet long – less than half as long as an Orca. The UK’s “Project Cetus” prototype XLUUV will be of a similar size.

A shorter hull means less volume, which in turn means less of everything that matters: batteries for underwater propulsion, passive and active sensors for navigating and detecting targets, computers for onboard artificial intelligence, weapons for striking other subs and ships on the surface.

It’s not clear which weapons the Royal Australian Navy plans to add to the Ghost Shark, but they almost certainly won’t include the RAN’s standard torpedo, the American Mark 48. The Mark 48 is 19 feet long – far too big for a 36-foot robo-sub.

There are smaller torpedoes, including a new seven-foot model Northrop Grumman has been developing for the US Navy. But if the plan is for the Australians to acquire and integrate a new mini-torpedo on their new robotic mini-sub, no one has made it official yet.

Even so, it’s good news for the Australians that they can build a UUV faster than the Americans can. Maybe the operational Ghost Sharks will possess only modest firepower. But they might possess modest firepower years before the American Orcas set sail on their first front-line missions.