at which place did he complete his aviation training at?
Royal Australian Air Force (RAAF).
Lester Brain
Brain's penchant for motorbikes and things mechanical inspired a lift driver at CBC to suggest he apply for pilot training in the recently formed Royal Australian Air Force (RAAF). 
who was lester brain? Australian aviator and airline executive where was he born? Forbes, New South Wales, Australia which school did he pass out from? Sydney Grammar School
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Lester Brain [SEP] Early life
Brain's penchant for motorbikes and things mechanical inspired a lift driver at CBC to suggest he apply for pilot training in the recently formed Royal Australian Air Force (RAAF). He was among five civilian students nominated by the Civil Aviation Branch (CAB) of the Defence Department for entry into the inaugural RAAF flying training course, which commenced at Point Cook, Victoria in January 1923. The benefit of these nominations from a military perspective was that although the destiny of the CAB-sponsored students was to be civil aviators, they would also be members of the RAAF reserve, known as the Citizen Air Force (CAF), and could therefore be called up for active service as and when necessary.