Ixixly said "Once again, I don't see this as that much of an imposition.".
I also wonder if you have flown at 10,000 ft. Previously, you could cruise at (say) 10,000ft, then pop up to 10,500 or 11,000 ft (subject to the transition layer) for a short period without oxygen to get over a buildup. Now you cant.
I agree its prudent to use oxygen early if you are going high. I'll often use it above 8,000 ft. But, prudence and mandatory regulation are 2 different things. When I did my hypoxia training (have you done that Ixixly?), I did an added segment where I operated at a simulated 14,000 ft for 30 minutes. At that density altitude your judgement is slightly impaired, but there are many circumstances where its a whole lot safer than punching into weather. Why can I not use judgement without running the gambit of CASA's strict liability regulations.
A favourite quote at the moment is from Les Abend from Flying magazine (quoted by Chesney Sullenburger in his book) which is along the lines that pilots are selected for their knowlege and experience, but assessed for their compliance. Its time CASA allowed us to excercise knowledge & expereience again.
Also, (unlike the USA), we cannot simply go and buy a portable system. The removeable / portable system in Australia requires an STC and flight manual supplement for the specific aircraft - hence another round of engineering order & flight manual revision costs on top of the oxygen system. We need the USA style expemtion from engineering orders for minor modifications.
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