Fleet of new submarines armed with $6bn worth of weapons

The Defence Department is poised to spend up to $6bn arming Australia’s new fleet of submarines.

Naval Group’s Shortfin Barracuda submarine.

The Defence Department is poised to spend up to $6 billion arming Australia’s new fleet of submarines with an arsenal of next-generation weapons likely to include underwater drones and anti-aircraft missiles.

Defence confirmed it had allocated between $5bn and $6bn on weapons for the 12 new subs, due to come into service in the 2030s.

The $5bn-$6bn price tag comes on top of the $50bn cost of the submarines and will cover arming the subs over the course of their operational life, which is expected to ­extend well into the century.

Defence has said it would build a new submarine every two years, meaning the last new sub will enter service in the 2050s.

With each sub having an operational lifespan of about 30 years, the navy is likely to be operating them well into the 2080s.

The Defence Department confirmed to a Senate estimates hearing that the money would fund “the full scope of weapons and deployable systems’’ for the subs.

“This includes torpedoes and missiles, as well as emerging systems and technologies,” it said.

Australian Strategic Policy Institute senior analyst Marcus Hellyer said emerging technologies made it very difficult to say what the final price for the subs would be.

Mr Hellyer said weapons on the new subs could include unmanned submersibles, anti-aircraft missiles and “smart’’ mines.

“The really interesting growth area is autonomous underwater vehicles,’’ he said.

“That’s certainly something that will increasingly shape undersea warfare.

“I’d be very surprised if Defence wasn’t looking at acquiring underwater vessels that can be deployed from a submarine.’’

Mr Hellyer said future subs would deploy relatively cheap, disposable drones as a network of sensors to detect enemy vessels.

He said as the technology developed, the subs would act as motherships deploying cheaper, unmanned submersibles that would perform surveillance roles, a mode of warfare called “human-machine teaming’’.

Modern submarines also had the ability to shoot down sub-hunting helicopters using vertical missile tubes, a capability the navy was likely to be exploring.

French company Naval Group will build a version of its nuclear-powered Shortfin Barracuda class submarine. The Australian variant will be conventionally powered.