Originally Posted by
WideScreen
Bottom line, such a vague specification would imply, the specified design item is allowed to fail on 50% of the "crews". Granted, it depends a bit on the way you define "average" as well, the average level fluctuating "during the day", however it still implies a huge amount of failures is allowed, according to the specification. Add enough of these specifications and the Swiss cheese holes start lining up.
And, having these vague specifications, it widely opens the door to specification (interpretation) manipulation by management, as we have seen with the MAX.
I don't think the inclusion of "average" here implies any such thing about the failure "rate". While the acceptable rate of failure may well, and definitely should, be specified elsewhere in the legislation, in this case surely this is merely specifying that procedures to cope with the failure of any component must not depend upon techniques that the "average" pilot might not be able to master within the course of their career development and specific training to be approved to fly the aircraft in question.
To your point about the vagueness of the "average pilot" specification, attempting to more tightly define this at the legislative level would be a herculean task I would have thought. To date we have relied on the industry ensuring, as much as possible, that "below-average" pilots do not progress into flying positions that require "average" skills. While this sounds subjective, in my experience (as a military instructor pilot and senior international airline captain) I am very comfortable with the way "averageness" was tested non-subjectively. No doubt this is imperfect and boundaries will always be tested by the unscrupulous, but I wish the best of luck in the world to anyone who would try and codify in a central document exactly what the skills of an average pilot should look like. We should never let up on the unscrupulous 'tho.