Australia's $529 million Antarctic re-supply and research vessel will likely be out of action for the 2022/23 season due to a delay in sourcing spare parts.
The Australian Antarctic Division (AAD) says it has "moved swiftly" to adjust shipping plans to the frozen continent and is assessing implications for scientific projects.
The RSV Nuyina arrived in Singapore in April for scheduled maintenance and was due back in Hobart in October ahead of summer.
AAD director, Kim Ellis, said works included improvements to the icebreaker's hydraulic control system within the propulsion system clutches.
"While work has been progressing well on the clutches, an unexpected issue was discovered in the large couplings that connect the propulsion shafts with the clutches," he said in a statement on Friday.
"Following initial investigations and testing, the manufacturer has determined that shaft couplings need to be replaced.
"Delivery time frames for replacement couplings are lengthy, driven to a large extent by material shortages and supply chain issues."
Nuyina, which undertook its first two Antarctic voyages earlier this year, is unlikely to be ready for the coming 2022/23 season, Mr Ellis said.
The AAD has chartered icebreaker Aiviq as well as ice-strengthened cargo ship Happy Dynamic to transport critical cargo and bring expeditioners home.
"Change-over dates for the 90 expeditioners currently living and working at Australia's four research stations in Antarctica and on Macquarie Island will remain much the same," Mr Ellis said.
"Aiviq was chartered to refuel and resupply our stations last season and remains in Hobart for the season ahead."
Chief scientist Nicole Webster said the AAD was examining implications for science projects.
Nuyina, named after an Aboriginal word for southern lights, will be in a commissioning and trial phase for at least the first two years of its service.
Its maiden Antarctic voyage was pushed back several days due to issues with the ship's alarm and monitoring system.
