Quote from vilas:
Let's say Valpha prot is 5 degrees (in cruise) and rapid increase in angle of attack causes protection mode to engage at 3 degrees but the rapid pitch up will take it past 5 degrees and when the gust has passed it will pitch down to 5 degrees. Where is the problem? If pitch up was gradual there won't be any phase advance and it would have engaged at 5 degrees and it will resist any more pitch up if possible or will come down to alpha prot when possible.
Forgive me, but I'm finding it difficult to be sure which of your figures are AoA, and which are Pitch. My original concern about AoA-mode was that, if engaged by a brief up-gust, it may initiate the entry to a zoom climb with zero stick. This may have happened in the A340 AIRPROX incident, although the overspeed was also a factor in the pitch-up.
We seem to be repeating ourselves?