RSV Nuyina is returning to its home port of Hobart today after a successful journey through the Southern Ocean to resupply Davis Station. It’ll be a welcome sight for dozens of weary expeditioners, who’ve spent up to a year at the station.

“We’ve been away from our friends and family for 400 days so it was fantastic to see the Nuyina’s bright red shape coming through the icebergs,” Davis plumber Mick Cloke, who is on the ship,  said.

“You really know the end is in sight then but there’s still a mammoth task ahead, with the resupply and handover.”

Before the ship left Davis, the expeditioner band The Red Hot Chilli Penguins gave a final performance on ice (above). 

The ship left Hobart on Voyage One on October 10, with 80 passengers and 35 crew on board.

After a few days in Burnie to fill up with what’s known as Special Antarctic Blend – a fuel that’s refined so it doesn’t solidify in extreme cold – the ship headed south to find the right kind of ice to conduct ice trials.

The Nuyina is designed to break ice that’s 1.65 metres thick at a speed of three knots in a straight line but it hadn’t been formally put through its paces.   

After the ship cut a swathe in, engineers got down on the ice to test it for things like thickness, density, salinity and strength.

“We lifted someone down to the ice using the ship’s main crane in a personnel basket,” technical and engineering support manager Michael Zgoznik said.

“They tested the thickness using a cordless drill with a very long drill bit.

“We then deployed a brow from the vessel so people could walk to and from the ship from the ice, very similar to how they do it in port.

 “We also put an ice radar on the front of the vessel to monitor the ice thickness to help us understand the ship’s fuel usage … during the trials.”

The final report isn’t finished yet but is likely next year.  

Resupply delayed "out of an abundance of caution"

After a relatively calm journey, the ship reached Davis in mid-November and parked up in the sea ice so the resupply could begin.

It’s a massive logistical exercise, requiring all hands on deck.

Cargo is unloaded onto trucks and sleds and taken back to the station across the ice while water and fuel are piped over.

The plan was to transfer more than 350 tonnes of cargo, 200,000 litres of water and 750,000 litres of fuel.

But at one stage, it looked like it might not happen.

There were concerns the ice was deteriorating earlier than usual and might not provide the stability the cargo transfer required.

 “We need a certain thickness of ice and quality of ice to safely provide a platform that can bear the loads that we need,” Operations Planning Manager Robb Clifton said.

“In a period of of bad weather, the ice started showing signs of losing or lacking stability so out of an abundance of caution we halted operations until we could do a full assessment in conditions where we had enough visibility to really understand what was going on.”

When the weather cleared, rigorous testing was done and the decision was made to continue.

Ship proving to be "incredibly capable icebreaker"

It took more than 30 hours to transfer all the fuel, with people walking up and down, monitoring the fuel line for leaks or problems the whole time.

More than 200,000 litres of water was also piped across. 

 “It would have been a serious disruption to the program if we’d had to delay resupply,” Mr Clifton said.

“We wouldn’t have had enough water on station to sustain the whole population so some of the expeditioners would have had to turn around.”

It would also have meant transferring the responsibility to Voyage Three.

Despite some testing moments, Voyage One is considered a resounding success.

“The ice testing that was done is considered to have gone really well,” Mr Clifton said.

“The ship is proving to be an incredibly capable ice breaker.”

Director of Maritime Assets Kriss Lawler said: “The overall success of this voyage is testament to the skill, experience and dedication of all on board.”