Originally Posted by PJ2
Here is a buffet boundary graph for an A330:
That's a nomogram.. very clever things nomograms. Reading them can sometimes be, er... 'less than obvious'. Drawing them up, even more so...
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I can see the good sense in the alt.hold being 'soft' and Mach being 'harder' presumably - but there might be questions coming on auto-flight presumptions, philosophy & man/machine interface in general, for AF447, as well as two others currently under investigation.
Aware that you may well not sign up to that, even as pure speculation at this stage.