Four people, including the pilot, were killed and a fifth was seriously injured when the Keystone Air plane hit the icy surface of North Spirit Lake in January 2012.
Safety board spokesman Peter Hildebrand said the plane was forced to circle the runway servicing the North Spirit Lake First Nation for almost half-an-hour while he waited for it to be cleared of snow. As the plane circled, Hildebrand said, ice built up on the wings and tail.
This caused problems when the plane finally began to descend.
"Eventually, the aircraft built up enough ice that during the change in configuration — extending the landing gear and extending the flaps — the drag increased. The lift was no longer sufficient," said Hildebrand, who is regional manager of air investigations.
"The aircraft stalled and crashed."
The plane crashed about 1 1/2 kilometres short of the runway, Hildebrand said.
Residents of the northern Ontario reserve about 400 kilometres north of Dryden, Ont., said there was a blinding snowstorm at the time. Many rushed to the crash sight and tried dousing the flaming wreckage with snow, but couldn't save four people trapped inside.
Pilot Fariborz Abasabady, 41, died along with Ben van Hoek, 62, president of Aboriginal Strategies Inc., an administrative service for First Nations in Winnipeg.
Colette Eisinger, 39, an accountant for the company, and Martha Campbell, 38, a band worker for the North Spirit Lake First Nation, were also killed.
Brian Shead, a 36-year-old employee with Aboriginal Strategies Manitoba, was injured but survived. He would later describe how he tried in vain to unstrap the other passengers from their seats and put out the fire on the wing.
He said he managed to pull the pilot out of the cockpit window before collapsing in the snow.
The pilot had 2,500 hours of flight time, but didn't have experience flying into remote areas in icy weather, Hildebrand said. Abasabady had worked for Keystone for four months. It was his first job as a commercial pilot, Hildebrand said.
"The pilot's experience had been in a different sector of aviation, so making the transition put him into a situation where it was difficult to foresee all the things that would be faced in a flight such as this."
Keystone Air declined to provide anyone to comment on the report, but issued a two-sentence statement thanking the Transportation Safety Board for its work.
The airline, which operates charter flights in Manitoba, has revised its operations manual to clarify what planes are capable of in icy conditions, Hildebrand said. The airline has also followed the board's suggestion to add a second pilot on flights that might run into icy weather in remote areas.
That allows one pilot to focus on flying while the other can monitor the plane's condition and take steps to address ice buildup if it occurs, Hildebrand said.
The crash prompted northern aboriginal chiefs to call for higher aviation standards and better emergency response and weather equipment in isolated native communities. By the time a worker arrived at the North Spirit Lake airstrip and found it covered in snow, the doomed flight had already left Winnipeg.
Hildebrand said the board did not make any recommendations to address weather conditions or equipment in remote communities.
"It's a fact of life in terms of remote, rural airport operations; however, it's something that people need to be very much aware of," he said. "That applies to airline operators and that applies to pilots as well.
"This is the reality out there."