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Old 10th January 2023 | 07:26
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OPEN DES
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The AP will trip off at alpha prot + 1 deg (a320 ceo) some phase advance for pitch rate considered for a318/319/319 ceo and all neos.
Alpha floor activation by fac (alpha) or elac (alpha/pitch plus sidestick nose up demand) is indeed inhibited above M0.6 for all variants.

Once alpha prot is activated it is nominally a latched condition whereby sidestick controls alpha directly. Sidestick neutral=alpha prot, full sidestick=alpha max.
However phase-out will happen when certain specific conditions are met, mostly when High Lift devices are out and/or close to the ground. (I.e no latching) Otherwise nominally alpha prot is phased out when forward sidestick is applied (function sidestick deflection and time).

Alpha prot value depends on variant and starts to decrease beyond M0.3 (due Mach compressibility effect).

Alpha floor activation (< M0.6) normally occurs after Alpha prot threshold however can be phase advanced by ground speed/head wind gradient in landing config.
Alpha floor activation can also be independent of filtered alpha purely, when high pitch (25deg) and/or high aoa prot is active and sidestick deflection > 14deg.

So in your scenario expect the AP to trip first, and then the aircraft to reach and maintain alpha prot without alpha floor activation.
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