Hi TP,
I have no particular view on Jabiru engines, this is objective: Thanks for the explanation of what you meant by the 'disclaimer condition'. I know what Volenti means (I did raise it after all) and my original point was a simple one given this threads OP. The letter is directed to establishing it as a complete defence against liability.
I appreciate your analysis of the legislation also but your reasoning has drifted off topic and appears to have been conflated with individual negligence. What it is really all about (OP) is relevant to CASA and Jabiuru; The letter brings to the attention of individuals what is purported to be an obvious risk (with Jabiru engines) and attempts to bind the signing party to a voluntary assumption of that risk, so that CASA (and perhaps collaterally, the individual PIC) are excluded from liability.
If an individual properly operates, maintains, replaces, prepares or cares for the thing then they are, by definition, not negligent ('Properly' not Negligently). Regardless the real issue is that (and the examples in the legislation are of no assistance), as you would agree I anticipate, the argument (positive on the balance of probabilities) would be that the potential failure of a Jabiru engine is an obvious risk - given the history, discussion and action taken - add a letter signed by the party acknowledging and thereby purportedly solidifying that 'obvious' fact. Ergo: CASA = 'WE have a complete defence from negligence'.
Cheers