Our submarines are so operationally fragile that competing in exercises with allies has become a case of going in with fingers crossed that nothing goes wrong. Photo: Supplied

The cheeky headline last week from Defence media read "HMAS Farncomb celebrates successful sinking at RIMPAC" and I quietly cheered for the crew of the submarine for sinking their target ship during the 22-nation exercise off Hawaii.

The maintenance and sustainment issues that have dogged our Collins Class submarines must be very challenging on the morale of our dedicated submariners and this was a rare glimpse of what the sub can do.

If we want a viable submarine capability to defend our island nation over the next 20 to 30 years and we cannot afford to wait any longer. 

But then came the following day's announcement from Defence, HMAS Farncomb had suffered a minor flood while at periscope depth after a hose split and the vessel was forced to surface. Farncomb was now returning to Pearl Harbour for repairs.

Farncomb is no stranger to this kind of incident as the boat and its crew had two separate emergencies last year.

In August it lost both its propulsion motor and emergency back up in deep water off the Western Australian coast. The second, a few months later in the South China Sea, involved a build up of toxic gases that had the crew wearing oxygen masks and blowing its emergency ballast tanks for a rapid ascent.

In May last year another Collins Class submarine, HMAS Dechaineux was forced to return to Singapore for repairs after breaking down on its way to a training exercise, also in the South China Sea. It was the only submarine due to participate in the 5-nation exercise and the embarrassment was amplified when the Navy News published a pre-written account of its daring exploits on the presumption nothing could go wrong.

More concerning was the 2003 incident with HMAS Dechaineux off the Western Australian coast when the submarine had a burst seawater hose which allowed a flood ingress of 15 tonnes of water in 9 seconds just when the vessel was at its deepest diving depth.

The bravery and skill of HMAS Dechaineux's 55 crew ensured they avoided the worst military disaster since Voyager. I have often said that submarines, along with our Special Forces, are our nation's most important force element group.

Yet this year alone we will spend close to $1 billion on maintenance and sustainment of the Collins Class with sometimes two, sometimes one, and occasionally none out of six submarines operationally ready at any one time. So depressingly bad are the figures for Unit Ready Days for the Collins Class that Defence no longer publish them – citing security concerns even though they were regularly published up until 2009.

I readily accept the problems of our submarines transcend both Labor and Coalition governments. But what the Rudd/Gillard governments and the three Defence Ministers over that period have failed to do is to get the ball rolling on the Collins replacement submarine.

In May 2009, the Defence White Paper outlined ambitious plans for 12 new submarines to be assembled in South Australia under a project known as SEA 1000, with the first to be in the water by 2025. I say ambitious because there was no detail whatsoever as to how we were going to pay for them in the White Paper and conservative estimates have the cost at $36 billion although I believe it will be closer to $50 billion.

For three years after the launch of the White Paper the SEA 1000 project sat in a file on successive Defence Minister's desks with no action whatsoever. Defence commentators and experts all began to get nervous and earlier this year the government's own funded thinktank, the Australian Strategic Policy Institute, published a damming report warning of a significant capability gap and noting inaction was not a responsible option.

The ASPI report described the gap between when all the Collins Class have been retired and the time it would take to build a replacement as ''nothing short of catastrophic'' where Australia's submarine capability would ''essentially be run down and restarted'' and there are three years ''of no submarines at all''.

The Defence Minister's recent answer to that was to repeat the announcement from three years ago that the Navy was to acquire 12 new submarines, and there was to be a $214 million 'scoping study' to look at the options.

Why wasn't that done after the White Paper launch? These past three years of sitting on their hands will come back to haunt our submarine capability long after this government is consigned to the history books. After some prodding the Minister also declared a final decision on the replacement would not be made until late 2013 or 2014 – in other words, not until after the next election. He wants to make it someone else's problem, not his.

This is all against the backdrop of our submarines being so operationally fragile that competing in exercises with allies becomes a case of going in with fingers crossed that nothing goes wrong.

We also have our submariners reluctantly leaving the Navy because they simply don't get time at sea doing what they signed up to do. We are losing some of our most experienced submariners and it is precisely that experience that has probably prevented these incidents becoming major tragedies for the Navy and the nation.

If the latest incident with HMAS Farncomb tells us anything about the state of the submarine fleet, it is that the time for talk of a replacement for the Collins Class is over.

It is now five minutes to midnight if we want a viable submarine capability to defend our island nation over the next 20 to 30 years and we cannot afford to wait any longer.

Senator David Johnston is the shadow minister for defence.

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