An aircraft flying an Antarctic medical evacuation mission has arrived at the British Antarctic Survey's Rothera Station.

The plane, carrying two patients, arrived at the outpost after leaving the National Science Foundation (NSF) Amundsen-Scott South Pole Station in the early hours of Wednesday morning.

The aircraft arrived yesterday afternoon at the station, at which point the crew began a 10-hour rest period.

The team then checked the weather at both the pole and Rothera, and decided the conditions warranted flying immediately north.

While the mission originally planned to evacuate one sick worker, the NSF determined the team would use the opportunity to evacuate a second patient.

"Both patients are seasonal employees through Lockheed Martin Antarctic Support Contract, the prime contract for operations and research support to NSF for the U.S. Antarctic Program", the NSF says.

Both patients have now been flown to a medical facility at the South Pole.

NSF says it is not discussing any details of the patients' medical conditions, or providing any personal details.

There are 39 men and nine women currently at the NSF station.

Workers at the South Pole are isolated from February through to October, the coldest and darkest months, when it is considered too risky for routine flights.