Three titles worth reading:
1. Murray JD, "The last Waggons" has a section on the RCASC officers who became Army pilots, flying primarily helicopters.
2. Foster D., "Canada's Flying Gunners". Covers Canadian Artillery officers who became pilots in WW2, flying light aircraft and photo-recon fighters in RAF and RCAF squadrons and post-war Canadian Artillery flying L19s and Hiller helos. Lots of photos.
Author unknown, "Blackdown to the Wild Blue Yonder". One officer's personal story of his military career in the RCASC from Driver to Pilot.
Soon to be released at last report
Artillery Flyers At War - the story of the 3 RCAF/RCA Air OP Squadrons of the Second World War, by Darrel Knight. I believe Vanwell is considering this one. Good details of all three squadrons; some mention of James Doohan, but most attention paid to those who actually flew operationally. Looks to be a good one.