No. 3 Bombing and Gunnery School

Air Gunner RCAF crest

"Airmen were granted their Wings in graduation ceremonies and often rushed back to the barracks to stitch the badge on to the uniform. Wing badges were worn on jackets on the left side over the chest."

Source: http://www.abheritage.ca/flyboys/homefront/uniforms.htm

This image is from the uniform of Cameron Clare Campbell, and supplied by his son and daughter-in-law, Lloyd and Susan Campbell.