It remains Nz law, so the delta between NzCmd and NzAct = FD bar position. e.g. if you are on commanded trajectory the FD pitch bar will be neutral. (NZCmd = NzAct)
AMM:
The pitch FD bar command is computed by using the measured vertical acceleration (NZ) and the NZFD command (pitch outer loop).
The gain and the limitation of the bar command are different according to whether HDG-V/S or TRK-FPA has been selected on the FCU.
With HDG-V/S selected, FD pitch control command is limited to plus or minus 22°5, and with TRKFPA selected,
FD pitch control command is limited to plus or minus 50°.
You need to calculate NzCmd from 'smoothened' SS input...
Max SS = +/- 16 degrees.
