A desperate search is on at the bottom of the earth for three Canadians aboard a missing plane in Antarctica.

The DHC-6 Twin Otter, owned by Calgary-based Kenn Borek Air Ltd., disappeared Wednesday night while en route from the South Pole to an Italian base in Terra Nova Bay.

Search officials in New Zealand say the plane's emergency locator beacon is sending out a signal from along the flight path.

An American rescue plane was dispatched to but the search for the plane has been unfruitful.  Low cloud coverage and high winds are making the search efforts very difficult. 

New Zealand media is reporting that the three people on board the plane are employees of Calgary-based Kenn Borek Air, a detail not yet confirmed by the airline.

Kenn Borek Air has years of experience flying in the Arctic and Antarctica.  The company charters flights for expeditions, oil exploration, tourist excursions and air ambulance service.

In 2001, a Kenn Borek Air crew plucked a doctor to safety from a South Pole station and in 2007, all 12 people on board survived when a Kenn Borek flight crashed on takeoff in Antarctica.