Investigators may never determine what caused the private jet carrying Jim Prentice, the former premier of Alberta, and three others to slam into a wooded hillside roughly eight minutes after taking off from Kelowna's airport, killing everyone on board.
Over the coming months, experts at the Transportation Safety Board will try to determine what caused Thursday's fatal crash using radar data, inspection reports and any physical evidence recovered from the wreckage 18 kilometres north of Kelowna.
That process will be complicated by the absence of a flight data recorder or a cockpit voice recorder in the small Cessna plane, which as a private plane is not required to have such tools, TSB regional manager of aviation Bill Yearwood said Sunday.
"Because of the lack of a flight data recorder or a cockpit voice recorder we have less to look at and that adds a bit of complexity to the investigation," Mr. Yearwood said. "We have to try and determine the cause and if we can't find the ultimate cause – because of the lack of information – of course there will be some findings regarding that."
The investigation will take upwards of a year, he said.
Investigators have talked to pilots who flew in and out of the airport around the time the plane crashed so they can assess the flying conditions, Mr. Yearwood said.
No distress signal or mayday call was received before the jet hit the ground "at a very steep angle," he added.
Pilot Jim Kruk, a retired Mountie, had flown the Cessna into Kelowna on Thursday morning from a Calgary-area airport so Mr. Prentice, optometrist Dr. Ken Gellatly and retired businessman Sheldon Reid could play golf.
Mr. Reid's company was one of four that shared the use of the plane, which was always flown by Mr. Kruk, according to co-owner Jed Wood. Mr. Kruk, who had flown for decades and frequently since he retired from the RCMP in 2007, would not have played golf with the trio before returning to Calgary after eight hours in Kelowna, Mr. Wood said.
"He's a professional, he would have taken his off-duty hours, rested and then flew them back," said Mr. Wood, who has flown across Western Canada numerous times with Mr. Kruk over the past three years. "That'd be the best way to describe him: a professional and a gentleman."
Mr. Kruk was the chief pilot for Norjet, the company that shared the jet between its four owners, but occasionally he had a co-pilot on different flights, Mr. Wood said.
Mr. Kruk's friend Kevin Moore said the pilot's family was passionate about aviation, noting his two teenage sons are involved with Air Cadets in Airdrie, north of Calgary.
"His oldest son is a licensed pilot as well at this point, and the younger son is in the process for that as well. They are an aviation family," Mr. Moore said.
The plane was built in 1974 and has had numerous owners, but, like any private jet, would have had to have been inspected and maintained so that it operated as if new, Mr. Yearwood said. The TSB's office in Edmonton has the plane's inspection records, he said.
The crash shocked the whole country late last week when news spread of the death of Mr. Prentice, a former senior federal cabinet minister and premier of Alberta. Since then, tributes have poured in for Mr. Prentice as well as his fellow passengers: Mr. Kruk, Dr. Gellatly and Mr. Reid.
With a report from The Canadian Press