After days of delays, a rescue flight headed to the South Pole on Saturday to pick up an ailing worker at the research station there.
Snow and wind had delayed the rescue attempt for five days while the rescuers awaited at British Rothera Air Station on Antarctica, 1,346 miles from the pole.
"It left at 6:48 a.m. Mountain time with estimated time of arrival 4:48 p.m.," said Valerie Carroll, spokeswoman for Raytheon Polar Services, the Centennial, Colo.-based company that manages the polar station.
"The plan is for a 10-hour flight, 10 hours of rest, then 10 hours back. But that is flexible," said Carroll. The employee will then be flown to the southern tip of Chile for the return flight to the United States.
The weather was partly cloudy at Rothera with winds of 24 mph and visibility at 12 miles. At the polar station, the temperature was 66 degrees below zero with winds of 18 mph and visibility of one mile. The forecast was for overcast skies.
The ill employee, whose name is being withheld at his request, is ambulatory but may need surgery. Raytheon has declined to confirm reports he is suffering from a bladder infection.
The rescue plane is a Twin Otter, a rugged twin-engine plane designed for rough weather, and capable of landing on small landing strips.
It is the third such rescue in four years, and is occurring in total darkness. The sun doesn't come up at the South Pole until Tuesday when the southern hemisphere spring arrives.