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I was wondering if any of the (E)GPWS callouts would make the autopilot disconnect? If the Alpha Protection is active (like in Bilbao, 2014) would it disconnect? That would give PF full control of the aircraft and could help to recover from the upset, correct?

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    $\begingroup$ Comments are not supposed to be 'thank you' or the equivalent... but ... thank you for not joining the masses and mass media by condemning the pilot. It seems everyone 'knows' his mental state is involved, even before the FDR is (if ever) recovered. $\endgroup$ – CGCampbell Apr 1 '15 at 18:17
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    $\begingroup$ I heavily reworded the question to remove non necessary reference that would invite speculations (that would be off-topic) and I aimed in keeping the original underlying question untouched. If you feel that this has been excessive, you can revert my edit. $\endgroup$ – Federico Apr 1 '15 at 18:41
  • $\begingroup$ It should be noted, that the Bilbao incident was caused by flight envelope protection, which is different system from autopilot and never disconnects unless the air data units indicated fault or are switched off manually. The EGPWS alert procedure from the answer below even relies on it by saying "Pull up to full stick and maintain", which would cause a stall without flight envelope protection. $\endgroup$ – Jan Hudec Apr 2 '15 at 9:05
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This is the Quick Reference Handbook procedure from an old A320 training manual.

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(The EGPWS procedure is a memory item, pilot's are not expected to look this page up when they encounter a EGPWS warning)

The first two sub items answer your questions. The autopilot needs to be switched off manually and the instruction is to pull up to full back stick and maintain. The Alpha protection will prevent the aircraft from stalling, that is why the stick can be maintained at full back deflection.

Airbus' safety magazine FAST #23(PDF) giving guidance on flying protected aircraft, specifically advices pilots to apply full backward stick deflection in GPWS situations since the alpha protection will prevent the aircraft from stalling and the resulting flight path is the most effective way away from danger.

To illustrate a possible the effects of Alpha protection in an (E)GPWS situations, let's go to Bilbao again, but now in March 2001(PDF). An A320 on final approach encountered a wind shear causing the aircraft to descent fast. This caused the GPWS to trigger a warning. The pilot applied TOGA power and back stick deflection, but the Alpha protection predicted the aircraft to stall and prevented a higher nose attitude. As a result the aircraft didn't stall but crash landed on runway threshold. This accident demonstrates that the GPWS does not affect the flight envelope protection system.

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No, the EGPWS is a warning system, and does not typically interface with the autopilot. The first step in reacting to EGPWS (or most TCAS) warnings is to disconnect the autopilot & autothrottles and fly manually, but this isn't accomplished by the EGPWS itself.

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