PJ2
By "do nothing", I didn't mean literally sit there, hands-off doing nothing
PJ2, Thanks for the clarification.
If they had been in
Alt1 law, I would expect the aircraft to pretty much hold the attitude that it was in when the Autopilot dropped out. Control feel would then have been virtually the same as Normal Law. The PF could probably have almost taken a hands off approach to the situation without getting in too much trouble too quickly.
Since he was in
Alt2 law, he had to fly the lateral channel and try to stay off the pitch channel unless a correction was necessary. This did not happen it seems.
Since the turnover briefing specifically included the discussion about the aircraft not being ready to climb higher, there are approximately two reasons the aircraft would be put in a climb.
- PF airspeed indication approaching Mmo or
- It was inadvertent.
The bulk of the PF's turn at the stick apparently involved nose up inputs by him, even after the the stall.
Conclusion: The climb was inadvertent.
What would cause an inadvertent climb?
If you rule out a malfunction of the pitch channel of the flight control system causing an inadvertent climb, (we will get back to this later.), then what appears to be left is a very serious lateral control problems taking the full attention of the PF.
The BEA note seems to indicate that the PF was making frequent large control inputs.
Large control inputs (high gain activity for the control theorists) are contrary to this Pilots training. Something scared the Bejesus out of him to get this type of behavior.
The only thing that makes sense is that he encountered lateral PIO (And PIO is definitely an aircraft problem).
Another name for PIO is pilot in the loop oscillation.
Can we rule out a pitch channel malfunction? Probably not with the data we presently have. We will have to wait for BEA confirmation of more details.
Just my take on the situation. There are enough holes in this concept to drive a truck through right now. More information is needed.