Sparks are seen on the video of the right inboard axle of the wheel and then the wheel rolls off at high speed as the airplane lifted off.
EDIT: It's the left inboard side.
Air Canada (Jazz Aviation) Dash 8-300 lost a wheel on takeoff at Montreal-Trudeau with 49 passengers and a crew of 3 on the way to northern airport Saguenay on Friday afternoon. Plane burnt fuel to reduce weight and returned to Montreal.
French passenger with France accent says "It fell off, it fell off".
See good video of the axle sparking and wheel falling off in
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