Originally posted by 3WE
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It is extremely likely that Airbus used the envelope protection as an alternative means of compliance giving "at least equal levels of safety" than the required stability. Unfortunately, when the system degrades from direct law to alternate law it keeps the lack of longitudinal stability but it looses a good bunch of envelope protections (especially if it reverts to abnormal alternate law, as would happen during a UAS event).
That's why in the AF thread I was ranting that the airplane should revert from some law to either other law that keeps the envelope protections or to direct law where the airplane becomes longitudinally stable and behaves... well, like an airplane, and that a mode that eliminates the protections but retain the indifferent stability (stick-on-G) should be a no-no and should not have been approved.
That was before we learnt that the pilot was "pulling up all the time" so they would have equally efficiently stalled a Piper Cub.
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