Both Const. Michael Potvin and Cpl. Brent Chapman knew that the boat at the Mayo detachment had a history of problems when they took it out on the Stewart River on July 13, 2010, but they went out nonetheless.
The boat would capsize that day. Chapman hung on to the boat and survived, but Potvin drowned trying to swim for shore.
The day before the accident, Chapman was told that the boat “had almost killed two people” the last time it had been taken out in October; but that was only part of the story.
The boat, which was custom-built for the RCMP in 1985, was first put into service in Old Crow. That same year the boat sunk on the Porcupine River while carrying a heavy load of moose meat.
At the time it was built, there was no requirement to have a capacity plate – a metal stamp that displays the maximum weight the boat can carry, the number of people and the recommended size of the motor.
After it sunk, the boat was hauled up, dried out, and in 1987 it was sent to the RCMP detachment in Carmacks.
Over the years there were a myriad of modifications made to the boat.
Neither Chapman nor Potvin knew much about the boat’s past.
The administrative file that detailed its history contained very little information.
At the time of the accident, though it was required, the Yukon RCMP didn’t have a basic water transport co-ordinator to keep track of boat history and maintenance records.
Investigators had to reconstruct the boat’s history by examining accounting records and receipts from mechanics.
Sgt. Mark London, the lead investigator into Potvin’s death, told the inquest that he was never even able to find the actual report into the 1985 sinking, only a reference to it in another document.
After Potvin’s death the boat was recovered and taken from Mayo to Vancouver where it was examined by navel architect Alex Brydon.
“The weight of the motor was fundamental to the whole accident,” Brydon told the inquest.
At the time of the accident the boat had two motors, a 150 hp main motor that weighed 474 pounds as well as an auxiliary motor that weighed 115 pounds.
It was a 500 per cent increase in weight from the 118 pound, 50 hp motor that originally came with the boat.
Brydon calculated that the maximum weight the boat could carry was 603 kg, with a maximum capacity of four people, and a maximum engine size of 70 hp.
However, that was only the case if the motor well was intact; it wasn’t.
Someone at some point had also cut down both the transom (the back wall of the boat) as well as the motor well, and had also drilled holes into the motor well itself, holes that allowed water to flow onto the deck of the boat.
A motor well is supposed to take in water that spills over the transom and stop it from reaching the deck.
Brydon told the inquest that he’d never seen fuel lines or wires running through the side of a motor well before.
“Knowing that motor well isn’t water tight, I get nervous,” he said.
The fact that the bilge pump – which pumps water off the deck – wasn’t working was also a significant factor in the accident, said Brydon.
When investigators took the pump apart, they found it full of mud. They cleaned it out, hot-wired it to a battery and it worked, but when they hooked it up to the boat’s electrical system, it shorted out.
The boats entire electrical system was improperly installed, said Brydon.
“The wiring was not up to standard,” he said. “Not even close.”
There was rust on the fuse panel, no ground installed and the wiring was not properly secured.
The wire that ran to both the navigation lights and the bilge pump had fallen behind one of the fuel tanks. Because the fuel tanks were also improperly installed, they were able to move around and rub the insulation of the wire, causing a short.
The design of the boat was also a factor.
When boats get swamped with water they are expected to sink down but retain their stability.
While boats aren’t supposed to capsize when they take on water, unfortunately many do, said Brydon.
The Mayo boat had two sealed air compartments to help maintain buoyancy.
Because of the position of those compartments the boat had a tendency to capsize when swamped, said Brydon.
In tests done after the accident the boat started to flip before it was even half filled with water.
There was also a blockage in the fuel filter that caused the motor to stall.
“Had (the blockage) not been there, I doubt we’d be here today,” Brydon told the inquest.
Not only was the fuel filter too small for the motor, but when investigators pulled it apart they found a small piece of wood was restricting the flow of fuel.
That piece of wood has always bothered Brydon.
It couldn’t have come from the fuel tank because the fuel line was too kinked to let it by, he said.
The only explanation he could think of is that someone had tried to clean out the fuel filter with a stick.
“It’s the only thing that makes sense, and it doesn’t make sense,” he said.
The blockage allowed enough fuel to get the engine started, but not enough to keep it going with the throttle up.
When the motor stalled abruptly, the wake would spill over into the motor well, and because of the holes that had been drilled in it, that water would flow onto the deck.
Chapman testified that the main motor stalled four times before he went back to try to run the auxiliary motor.
By the time Chapman went aft, the accident had already happened, said Brydon.
He estimated that there could have been as much as 105 litres in the boat before anyone noticed.
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