The Royal Australian Navy’s fleet of six Collins class submarines is a formidable element in Australia’s defence capability and the chance to take a look inside one does not come along too often – some would say it is a very rare opportunity.

Faifax Media was recently offered the chance to check out the HMAS Dechaineux while it was docked at Garden Island in Sydney.

Dechaineux’s Executive Officer is the Canadian-born Timothy Markusson who greeted the 10 lucky people on the tour and explained that the subs were the pride of the Navy.

The role of the Collins class sub is undersea warfare.

The Dechaineux is just 77.8 metres long and it can travel at a top speed of 20 knots.

Armaments include: missiles, torpedoes, mines, physical and electronic countermeasures, radars, sonars and a weapons control system.

The motto of the Dechaineux is ‘fearless and ferocious’.

Following EO Markusson’s introduction, those on the tour descended a ladder into the belly of the boat – it was tight and cramped and once down the bottom we could see just how close this crew of 60 submariners have to work together.

The crew is totally self-sufficient – there are officers, drivers, electrical technicians, medics, chefs and many more positions.

Every person on board is so highly trained that they can jump into another role at a moment’s notice if required.

“Everybody from the cooks to captains needs to know the basic operations [of the submarine],” EO Markusson said.

The Commanding Officer is the only person who has their own cabin, some share rooms, while others sleep in bunks underneath and beside two-tonne torpedoes that are live and ready to be fired if required.

And while the sub has the ability to convert salt water into fresh water, the quantity the crew can use is strictly regulated.

The only people permitted to have a daily shower are the chefs and those working in close quarters with the hot, dirty diesel engines.

The submariners work in rotating shifts and “a day off isn’t really a day off”, EO Markusson said.

“When you’re at sea, you’re really at sea.”

There are no mobile phones, no land lines, no social media and no alcohol – even the on-board gym is squashed in beside bunks and torpedoes.

“You can really see the spirits lift when a port visit is scheduled,” EO Markusson said.

The Dechaineux can be deployed anywhere across the globe – there is enough food and supplies for weeks, however, regular surface visits must be taken to bring on fresh air and offload grey water.

“Our only limitations are gas [fuel] and groceries,” EO Markusson said.