From a group photo of the Sergeants' Mess in 1937 where we only had the last name and rank of Sergeant Gagnon, we have now tracked down the remainder of his story.
Flying Officer Lionel Edmond Charles Gagnon, a former Sergeant in the 15th Field Brigade, Canadian Artillery died in a flight training accident at Bagotville, Quebec. He was piloting a Hurricane which was in a mid air collision with a second Hurricane during a practice dogfight. Both aircraft were destroyed and both pilots were killed.
He was survived by his wife, Mavis Cecile Gagnon and Mother, Rose de Lima Gagnon, of Vancouver.