Planned upgrades for Australia’s Collins-class submarines to extend their service life will be dramatically wound back, with engine and motor replacements for six of the ageing boats cancelled they’re eventually replaced by a nuclear-powered fleet.

The Albanese Government will instead pursue an “enhanced sustainment” approach where HMAS Farncomb, one of the oldest boats and most heavily used, will begin comprehensive work within days, before other submarines are individually assessed.

Growing doubts are now emerging over how long the navy can keep the Collins-class submarines in the water, and what missions they could complete in the future, as Australia also prepares for possible delays in the arrival AUKUS boats.

“Informed by independent expert advice, detailed planning and industry engagement Defence will undertake a conditions-based sustainment approach across the life of type extension (LOTE) program,” the Government said in a statement.

“This will see Defence and ASC retain and restore base components, while continuing to upgrade critical weapons and systems. This will reduce engineering and schedule risks and ensure the Collins-class remains a formidable deterrent for years to come.”

Addressing the Lowy Institute, Defence Minister Richard Marles has confirmed the LOTE program will begin at the end of the month and cost $11 billion for the entire Collins fleet, up from an estimated $6b allocated in 2020 under the Morrison government.

“This will see a pivot in our approach that reduces risk, upgrades capability and maximises availability for the navy. We will prioritise sustainment and accelerate upgrades for the fleet’s youngest submarines,” Mr Marles told an audience in Melbourne.

“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.”

Under the massive AUKUS endeavour, Australia is hoping to extend the life of its Collins-class fleet, which began entering service 30 years ago, by another decade before the navy transitions to Virginia-class nuclear boats from the United States.

Defence says a “detailed engineering assessment period” will be carried out on HMAS Farncomb to tailor its life of type extension upgrades and to “inform work required across the class”.

Previous “life-of-type extension” plans included new main motors, diesel engines, and electrical generators for each of the six Collins-class boats to keep them running until the arrival of the navy’s planned fleet of nuclear submarines in the 2030s.

The Government insists safety will not be compromised, but there is no guarantee any of the boats will have all their critical systems replaced.

A classified review commissioned by the Albanese Government in 2023 and written by US expert Gloria Valdez is believed to have recommended that Australia not complete upgrades on all six of its ageing Collins-class boats before they’re retired in the 2040s.

“These decisions reaffirm the Albanese Government’s commitment to keeping the Collins-class a potent and highly capable strike and deterrent capability today, and for years to come,” Mr Marles said.

Former defence official Richard Gray, a senior resident fellow at the Australian Strategic Policy Institute, says today’s announcement confirms the LOTE program will take longer, cost more and deliver a reduced submarine capability than originally planned.

“As the Government acknowledged today it was always going to be a risky endeavour, so it’s understandable that they’ve tried to de-risk and de-scope the program,” he tells The Nightly.

In an ASPI report published earlier this month, Gray warned Australia could be left without a sovereign submarine capability if problems emerged on LOTE, and Australia’s plans to acquire submarines under AUKUS were delayed.

“There are always risks with these older submarines, including corrosion that’s hidden which you can’t fully assess until you cut them up. The risks do go up when you extend their life, and in future they might be restrained in the types of missions they can do”.

Shadow defence minister James Paterson took aim at the Albanese Government’s LOTE announcement, accusing Mr Marles of failing to properly secure enough funding for vital military projects.

“Richard Marles has used the cover of a remarkably partisan and defensive speech to admit a major de-scoping of the Collins-class life of type extension. As is often the case, he’s 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?”

“If Richard Marles put as much energy into persuading his expenditure review committee colleagues as he does attacking the previous government, maybe the ADF wouldn’t have to absorb as many cuts to capability as it has on his watch.”

Greens Senator and the party’s defence spokesperson David Shoebridge has derided the Government’s revamped LOTE announcement as “$11b more washed down the AUKUS drain”.

“We have known for years that this ‘life-of-type’ extension that Defence is dropping $11 billion on is extremely risky. This is what happens when you have a Department of Defence that is never held to account for failures and the war parties backing them in.”