Source: Simon Hradecky | www.avherald.com

An Air Canada Embraer ERJ-190, registration C-FHOY performing flight AC-442 from Toronto,ON to Ottawa,ON (Canada) with 60 passengers and 4 crew, was climbing through FL180 out of Toronto when the crew stopped the climb and decided to return to Toronto reporting an odour in the cockpit. The aircraft landed safely back in Toronto about 21 minutes after departure.

The Canadian TSB reported maintenance found the APU oil level at the high side and correcte the oil level. The APU intake cover and aft fuselage were found contaminated with oil, the areas were cleaned and the air recirculation filters were replaced.