Planned upgrades to Collins Class submarines scaled back   


ABC News
19 May 2026

The Collins Class submarine fleet will need to surface more frequently than nuclear-powered boats.   

In short:
Plans to upgrade Australia's Collins Class submarines to extend their life for a decade are being scaled back.

The submarines will no longer have their diesel engines and generators replaced, unless it is deemed to be absolutely necessary.

What's next?   
The $11 billion upgrades will keep the submarines operating into the 2040s, helping bridge a gap as nuclear-powered submarines start entering service.


A massive program of upgrades to Australia's aging fleet of Collins Class submarines, aimed at keeping them in the water a decade longer, is being scaled back.

The federal government says a plan to replace the diesel engine and generator in each submarine will not be pursued, and instead each submarine will be assessed individually and given the upgrade it requires.

It means that while weapons systems and other critical capabilities will be upgraded, most if not all of the submarines will operate their original engines until retirement in the 2040s.

The first submarine to go into the "life of type extension" process will be HMAS Farncomb in the next few years, the second-oldest submarine in the fleet at 28 years.

Richard Marles standing at a podium against a dark background.
Richard Marles addresses the Lowy Institute about AUKUS in Melbourne. 

In a speech delivered to the Lowy Institute in Melbourne, Defence Minister Richard Marles said the "enhanced sustainment" upgrades were a change that needed to be made.

"This will see a pivot in our approach that reduces risk, upgrades capability and maximises availability for the navy,"  he said.
A secret review carried out by Gloria Valdez, a former US Navy official, is understood to have found the submarines could continue to run for a decade without the engine replacement, and this approach would shorten the time taken to carry out upgrades.

The changes will also see additional resources put into some of the fleet's younger submarines, starting with HMAS Rankin, which is currently undergoing regular full-cycle docking.

HMAS Farncomb is expected to be the most complex upgrade, while younger submarines will require less complex work.

Mr Marles said the changes would ensure the work being done was tailored for each individual submarine.

"We will prioritise sustainment and accelerate upgrades for the fleet's youngest submarines," he said.

"The program will reduce engineering risk by sustaining existing systems where appropriate while continuing to upgrade critical capabilities, including weapons and combat systems.

"It has the transition to our future fleet of conventionally armed, nuclear-powered submarines as a key consideration."

A critical AUKUS step
The Collins Class submarines were originally envisaged to have a life of about 30 years, and HMAS Farncomb would have been retired around now.

Instead, $11 billion will be spent keeping the six submarines operational for 10 years longer than planned, and they will begin being retired in 2040.

HMAS Farncomb and HMAS Collins will both reach retirement age around then, with further submarines to be retired roughly every two years after that.

It is a significant cost upgrade from the original $4-5 billion estimate set aside for the project a few years ago, but the government argues the project was underfunded to begin with.

Federal government signs $2.2b deal to keep Collins submarines running
Three people wearing navy uniform stand on the deck of a large black submarine. which is sitting in water.
The four-year deal hopes to extend the life of Australia's current submarine class, half of which are dealing with corrosion, before they are replaced as part of AUKUS.

Under the AUKUS pathway, Collins Class submarines would operate alongside the Virginia-class nuclear-powered submarines arriving in the 2030s, and the AUKUS-class nuclear-powered submarines arriving in the 2040s.

The government argues the original plan, to replace the engines and generators in each submarine, was closely tied to a dumped plan to acquire French submarines, before AUKUS was agreed on.

The engines that would have gone into the Collins Class submarines would have, under an earlier plan, been identical to those used in the French submarines.

In the speech delivered today, Mr Marles said the new plan delivered everything needed to speed up the upgrades and keep submarines in the water for longer.

"This approach will ensure our Collins class submarines remain a potent and highly capable undersea platform today and for years to come," he said.

Shadow Defence Minister James Paterson said there was a significant amount of detail lacking on exactly what was no longer going to be upgraded in the Collins fleet.

"As is often the case, [Richard Marles] has failed to provide the details transparently to the public," he said.

"Which aspects of upgrades previously planned are now being abandoned? And how much is the Albanese government cutting from the program?"

whiteknight wrote on May 21^st, 2026 at 6:11am:



They print the money.

It gets paid for by inflation.

I agree.

By scraping the boats most unsuitable I imagine will create a wealth of spare parts for the boats that are still  sea worthy.

The only issue I see is why has it taken this long for a simple decision to be made?