Originally Posted by
DozyWannabe
Now - an interesting sim test would be to try stick-neutral just prior to the apogee, at the apogee and after the apogee (at the point where the PF slams the sick against the back stop) and see what the autotrim system makes of it. I'd be very surprised if the BEA haven't done precisely that, but a second opinion is always useful.
Given that Airbus is using C* based laws it would have tried to keep attitude. If the last commanded attitude was 10° NU, it would have tried to keep the nose there, if not corrected even into the stall.
This is confirmed in the report on page 187 (chapter 2.2.5.)
When there are no protections left, the aeroplane no longer possesses positive longitudinal static stability even on approach to stall. This absence specifically results in the fact that it is not necessary to make or increase a nose-up input to compensate for a loss of speed while maintaining aeroplane altitude.
and
The specific consequence is that in this control law the aeroplane, placed in a configuration where the thrust is not sufficient to maintain speed on the flight path, would end up by stalling without any inputs on the sidestick.
Simply levelling off and then letting the stick go should have helped until a speed of ~Mach 0,65 (Figure 65 in the report). After that even at level attitude the FCS would have started to trim into the stall once the propulsive limit had been exceeded. At that point sustained ND input would have been required.