Hi Machinbird,
Originally Posted by Machinbird
Originally Posted by Takata
Nonetheless, despite having a THS trim at +13 deg and being already in a full stall situation, it seems that those imputs are effective by reducing the AoA... hence, elevators were still effectives, don't you think?
Absolutely yes, but they ran out of authority against that great big THS.
I respectfully disagree with the second part of the sentence. So far, nothing in the BEA note is telling us that "they ran out of authority against" the THS at this point (0212:17). Such fact could only be established once we'll know how much nose down imput was applied. From the note, it looks like it was effective by reducing their AoA but it may also be the result of N1 reduction to 55%. In fact, you seem to agree with me later:
Originally Posted by Machinbird
We don't yet know how long the nose down input was held, do we? Only that it brought on the return of the stall warning. The stall warning may have stopped the crew's nose down input, or maybe it didn't.
Considering the low energy state they were in (airspeed was down to 185 kias at 0210:51), I'm prone to believe that those elevators imputs were still effective despite this THS trim... up to the point that their AoA would become an issue for recovering any control at all.
Anyway, my main point was to first focus on what information they lacked/missed in order to understand their situation until this point of the upset as I'm pretty convinced that this sequence as described at 0212:17 doesn't prove any understanding of their real situation.
As you said, this interuption of the "stall warning" until the very moment where the PF "started" to do something effective against the stall could have added to the overall confusion. But, IMO, it doesn't explain what signal didn't reach the PF brain (or induced him into doing the wrong thing) during the previous two minutes. This is what I'm focusing on, now, as this THS training seems a secondary issue when, at first, the pilot seem to be unable to aknowledge correctly what was primarily going on: a stall.