Source: Simon Hradecky | www.avherald.com

A Westjet Boeing 737-700, registration C-FWSK performing flight WS-662 from Calgary,AB to Toronto,ON (Canada) with 134 passengers and 5 crew, was enroute at FL390 about 40nm west of Winnipeg,MB (Canada) when an acrid odour developed in the cabin, haze was noticed. The flight crew worked the related smoke/fumes removal checklist and decided to divert to Winnipeg. The haze and odour dissipated after the checklist was completed. The aircraft landed safely in Winnipeg about 20 minutes later.

The Canadian TSB reported maintenance determined a malfunctioning recirculation fan was the source of the odour and haze.