Mounties say the site is inside the Cold Lake Air Weapons Range, an area used by military pilots for weapons training.
RCMP Cpl. Mike Dunsmore said the military and search and rescue personnel escorted police into the crash site late Friday and helped recover the body of the 38-year-old civilian pilot, who was the sole occupant of the aircraft.
But Dunsmore said the fire, which the province reported Saturday has grown to 40 square kilometres since it started a day earlier, is making it challenging for Transportation Safety Board investigators to safely enter the area.
Jon Lee, the regional manager for the TSB, said investigators were headed to the site in a helicopter on Saturday afternoon with a provincial wildfire official to see if it would be safe to land.
"If it is, they'll set down. If not, they'll re-assess," said Lee, noting the decision would be up to the provincial official.
Crews in northern Alberta have been fighting wildfires for more than a week, and warm and dry conditions have increased the fire hazard to high or extreme in some areas.
The pilot who was killed worked for Conair Aerial Firefighting, and he and the plane were contracted by the Alberta government.
"First responders like this pilot, and our many other dedicated wildland firefighters, put their lives on the line every day to ensure that our homes and families are safe," incoming premier Rachel Notley said in a statement that offered her condolences to the pilot's family, friends and colleagues.
"We owe them our most sincere gratitude. Even as they mourn the loss of one of their own, I know they will continue fighting the many fires burning within our borders."
Jeff Barry of Conair Aerial Firefighting said the pilot was in his fourth firefighting season with the company.
"We've sent our accident investigation team and we'll be co-operating with the Transportation Safety Board and the Alberta ESRD (Environment and Sustainable Resource Development) folks will be there as well," Barry said Friday.
Barry said the plane was a single-seater Air Tractor 802, known in the company as the "Fire Boss." The company's website said the amphibious plane is used to scoop up water from lakes or deliver fire retardent.
Police said in a news release on Saturday that the crash scene has been secured.
Lee said the crash investigation was still in the early stages and he couldn't speculate on the cause.
Lt. Mathew Strong, a public affairs officer at CFB Cold Lake, said unexploded ordinance won't be an issue for investigators.
"They're basically hunks of concrete that we drop from the aircraft for target practice," Strong said about the bombs, noting the live weapons range is a smaller area that's northeast of the fire.
He added that military crews track both live and non-live weapons for disposal.
Strong said a part of the range, the Primrose Lake Evaluation Range, was evacuated on Friday as a precaution due to the fire, but that the flames appear to be tracking away from the area. He said there were, however, some privately operated oil and gas facilities on the range that could still be in danger.
Cenovus Energy said in a news release on Saturday that it has removed 1,700 staff at its operation at Foster Creek due to the fire. It said the fire was about 30 kilometres away, but there was a risk the fire might close the main road to the operation.
It said Foster Creek is still running with about 100 essential staff members to maintain safe operations, but it added there are evacuation plans if the threat of the fire increases.
Canadian Natural Resources Ltd. said it has removed workers from its Primrose operations and temporarily shut down its crude oil production there.
Notley has appealed to residents to respect the fire restrictions that are now in place in the province.
—by Rob Drinkwater in Edmonton
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