My late father, then an RCAF Flight Sergeant, was heavily involved in the RCAF aspects of the movie. He was later (along with 9 others - mainly officers including Billy Bishop) given a directors chair by Warner Brothers. Despite some heavy usage when being moved from one RCAF station to another in the '50's, the chair has survived. Photo below.
Several months prior to the beginning of filming Harvard 2689 (# is behind the roundel) suffered fairly substantial damage in a forced landing near Uplands. My father supervised the recovery as shown in the following photo. 2689 was shipped off to Noorduyn for repairs and returned with a spiffy new paint job just before filming started. That, apparently is the reason it was selected for some of the PR photos and other close-ups.
Useless trivia from a long time ago.