The Canadian pilot of a plane missing in Antarctica has been confirmed as extreme polar pilot Bob Heath.
Heath is one of three men at the centre of a large-scale search started after the locator beacon in their plane was set off last night.
The plane, a Twin Otter, went missing on a flight from the South Pole to the Italian Antarctic base at Terra Nova Bay.
The three men aboard were Canadians and were understood to be working for Kenn Borek Air, a Calgary-based airline, Neil Gilbert, of Antarctica New Zealand, said.
Bad weather was hampering the search, with a C-130 Hercules able to only circle the area they are believed to be at a height of 22,000 feet, Maritime New Zealand spokesman Steve Rendle said.
Canadian newspaper Canmore Leader reported that the pilot has been identified by his wife as Bob Heath, from Inuvik, in Canada's northwestern territories.
His wife, Lucy, said she was "just waiting for news".
Heath was an experienced pilot and was quoted in the Australian media last year about his work.
"I have done nine or 10 trips to Antarctica as a pilot for Kenn Borek and worked for the Americans, Italians and tourist ops at Patriot Hills," he said.
"I also fly in the Arctic and do grizzly bear, polar bear and Beluga whale surveys.
Search and rescue mission co-ordinator John Ashby said a plane was battling "challenging" weather conditions.
"There are winds of 90 knots at the site, and conditions are forecast to worsen with snow becoming heavier."
He said that when weather conditions eased, a joint New Zealand-United States field rescue team was ready to go.
Ashby said the plane was equipped with enough survival equipment, including tents, for five days.
The pilot of the plane was believed to be experienced and well-equipped to survive in the cold.
The Rescue Co-ordination Centre New Zealand's Michael Flyger said that although the organisation had little information about the missing men, he understood the pilot was ''pretty well prepared".
"We would assume given his experience he's equipped to survive in these conditions."
He said initial resuce attempts were hampered by bad weather, but an aircraft was sent to search for the missing plane about 9am today.
It reached the general location about 11am, Flyger said.
He said the search plane had enough fuel for six hours.
The RCCNZ began handling the search after the missing Twin Otter's emergency locator transmitter was activated about 10pm yesterday.
The beacon was transmitting from the northern end of the Queen Alexandra Range, within New Zealand's search and rescue region.
While the RCCNZ was organising the search, US authorities were taking the lead locally, Gilbert said.
"The intent at this stage is to try to pre-position a campsite as close to where the emergency locator beacon has gone off."
He said Antarctica New Zealand was supplying a helicopter to go down to the campsite to help with the search.
It was hoped the search could be co-ordinated from the campsite because while aircraft could deploy from Scott Base, they could not travel any further than 50 kilometres from the site because of weather.
Search and rescue co-ordinator Mike Roberts said US authorities at McMurdo had been asked for assistance, and an Air National Guard C130 Hercules aircraft flew to the position but was unable to sight the downed plane.
Rendle told Radio New Zealand it was a good sign the plane's emergency locator transmitter was activated.
"We are in the early stages of the operation but one thing I have been advised of is the emergency beacon ... in a heavy landing can prevent the beacon working so that's a positive sign at this stage," he said.
Kenn Borek Air's website says the airline started in 1970 and runs one of the largest Twin Otter fleets in the world.
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