06/21/2016 01:58 EDT | Updated 06/22/2016 10:59 EDT

Kenn Borek Air To Attempt Medical Rescue Mission In Antarctica

Robert Schwarz, National Science Foundation

CALGARY — A plane was heading to the South Pole to pick up a sick worker at a research station.

The National Science Foundation says one of two Twin Otters owned by Calgary-based Kenn Borek Air was expected to arrive Tuesday at 5 p.m. ET.

The foundation says in a release the plane took advantage of a "favourable weather window'' and left this morning for the 10-hour flight.

The flight is necessary because a worker at the research station requires hospitalization and needs to be evacuated.

May need to rescue second patient

Foundation spokesman Peter West says there's another patient who may also need to be taken out, but that decision has yet to be made.

The other plane will remain at Rothera, a British station on the Antarctic peninsula, to provide search-and-rescue capability if needed.

West says no other details about both patients will be released due to patient confidentiality.

The planes left Calgary a week ago and got to Rothera on Monday. They were held up in Punta Arenas, Chile, since Thursday due to bad weather.

It's mid-winter in Antarctica and the foundation says flights in and out of the station are usually not planned between February and October due to extreme cold and darkness.

There is no tarmac runway at the Pole, so aircraft must land on skis in total darkness on compacted snow.

"The planes are rated to operate in temperatures as low as -75 Celsius, generally at Pole its about -60 C at this time of year but it fluctuates,'' West said.

Kenn Borek provides contractual logistical support to the Antarctic Program, according to the foundation, and conducted similar evacuations in 2001 and 2003.

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