Originally Posted by
Lead Balloon
The 3,000’ oxy was probably in preparation for those pilots transitioning to trained killer status with what would be now be impressive ‘Darth Vader’ breathing.
Perhaps it was a carry over from prior to 1947 at PCK, when the RAAF still had their Air Traffic Controller School there? The practice of Winjeel 3000' oxy being to give the student controllers experience at understanding 'Fighter Pilot Talk'.