In 1941, at the relatively older age of 31, David Hornell enlisted with the Royal Canadian Air Force. He received his pilot’s wings that July and was posted to No. 120 Squadron, based out of Nova Scotia. Hornell would fly patrols along North America’s east coast for the next two years, keeping watch for German U-boats that were known to lurk in the Atlantic, waiting to attack convoys headed for Europe.

September 1943 saw Hornell transfer to No. 162 Squadron, which was deployed to Reykjavik, Iceland on New Year’s Eve. From here, Hornell and company could monitor the passage from North America to Europe for enemy vessels. David Hornell began as a co-pilot before being promoted to pilot in May 1944. Around this time, No. 162 Squadron sent three Canso aircraft (including Hornell’s) to Wick in northern Scotland, where they were rotated into Allied deployments that monitored the European coastline for U-boat activity.