what is the rank structure here?
Aircraftman, Leading Aircraftman, Corporal, Sergeant, Flight Sergeant, Warrant Officer, and so on.
Royal Australian Air Force
As a result, the RAAF's rank structure came to be: Aircraftman, Leading Aircraftman, Corporal, Sergeant, Flight Sergeant, Warrant Officer, Officer Cadet, Pilot Officer, Flying Officer. Flight Lieutenant, Squadron Leader, Wing Commander, Group Captain, Air Commodore, Air Vice-Marshal, Air Marshal, Air Chief Marshal, Marshal of the RAAF.

who is mary bell? An Australian aviator and founding leader of the Women's Air Training Corps (WATC). what was the role of the corps? To provide support to the Royal Australian Air Force (RAAF) during World War II. when was this air force formed? March 1921 did it participate in any war? Yes, Second World War
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Royal Australian Air Force [SEP] Ranks and uniform
In 1922, the colour of the RAAF winter uniform was determined by Air Marshal Sir Richard Williams on a visit to the Geelong Wool Mill. He asked for one dye dip fewer than the RAN blue (three indigo dips rather than four). There was a change to a lighter blue when an all-seasons uniform was introduced in the 1970s. The original colour and style were re-adopted around 2005. Slip-on rank epaulettes, known as "Soft Rank Insignia" (SRI), displaying the word are worn on the shoulders of the service dress uniform. When not in the service dress or "ceremonial" uniform, RAAF personnel wear the General Purpose Uniform (GPU) as a working dress, which is a blue version of the Australian Multicam Pattern.