AMM describes the Pitch Nz law as:
1/ Nz Law
This FCPC law is the normal pitch law engaged during the flight phase.
The pilot commands a load factor via a pitch action on the side stick.
The Nz law executes this command, depending on aircraft feedbacks, so that:
- the short term orders are executed by the elevator servo controls.[/COLOR]
- the long term orders are executed by the THS actuator (autotrim function)
The gains depend on Vc, on the flap and slat position and on the CG position.
.....
Under the Nz law the aircraft response is quasi independent of the aircaft speed, weight and CG position.
And then it continues with a description of all kinds of protections, sub laws and system reaction in other flight phases.
The only functions which may be of any influence since they are also active in ALT law:
Abnormal attitude law,outruled by BEA but was it?
If certain values are exceeded abnormal attitude law is triggered.
- Pitch (50 degrees up, 30 degrees down)
- Bank (125 degrees)
- AOA (>30 degrees, < -10 degrees)
- Speed (>440 kt, < 60 kt)
- Mach (0.96, 0.1).
These (bold) values where - intermittently - present from @ 2:11:40 when Capt enters cockpit and on, that would justify the absence of autotrim when PF made ND inputs.
and
MLA (Maneuver Load Allevation) - but this would create a nose up pitch moment which should be counteracted by AND reaction.
This FCPC function is activated when the order of the pilot, via the side stick, exceeds a pre-determined load factor in clean configuration. A symmetrical deflection order is sent to the spoliers 4 thru 6 and the inboard and outboard ailerons.
The pitching moments due to MLA deflections are automatically compensated by the pitch control laws.
Taking into account the priority of the MLA function over the speedbarke function, if the MLA is activated when the speedbrakes are extended, spoilers 1 to 3 are retracted to zero and spoliers 4 to 6 are commanded according to MLA orders.
This function reduces the design loads during high-g maneuvers demanded by the pilot.