Hi airtren
Originally Posted by
airtren
The reasoning for returning the THS to a Stall Recovery Optimal Position - I picked Neutral as that seems the best candidate - is that from other BEA reports is that in other Stall incidents, unlike AF 447, where the THS was started the move UP after the Stall, the THS was further UP, or full UP already before the Stall.
I understand your point, it is valid but I still feel uncomfortable with it, because:
- it adds another layer of complexity to be aware of (KISS)
- it may be dangerous if stall warning isn't 100% reliable (and it's not)
- the crew must react to the stall by pushing ND. That would give ND elevators, then ND THS if the latter was NU by far.
(note : on AF447, if one accepts that the flight control surfaces acted accordingly with the crew inputs, the crew never pushed enough on their sidestick to make the elevators go ND, only less NU)
Originally Posted by
airtren
As long as the Stall is ON, as it is a slow move/reacting surface, I would not risk interference with the Elevators, which need be quickly very effective, and for short time intervals.
I don't think I understand which interference you may be refering to? I didn't suggest to limit the elevators in any way, only to prevent THS NU move.
I agree that if THS stays where it is, the recovery may be a bit longer than with the THS neutral (or ND), but as the crew has to push SS ND, elevators will go ND and eventually THS too.