"The FLAPS3 selection in the MCDU is just to allow the A/THR to command Vapp iso F-speed when the approach phase is activated".
I thought that the Flap selection in the MCDU would only change the VLs in the MCDU,and the A/THR would command the Vapp shown in the MCDU. If so, then my previous question may still hold since in step 4 we have manually inserted the Vapp.
Thanks
The Flaps3 selection in the MCDU changes the VLS and the resulting Vapp. However we donŽt care about that when applying a Vref increment, as the increment is always based on Vref (Vls CONF FULL).
The reason that we still select Flaps3 in the MCDU even when we have manually inserted a Vapp is due to the autothrust logic.
With the approach-phase activated the speed targets are as follows:
Conf0 - Green Dot
Conf1(+F) - S-speed
Conf2 - F-speed
Conf3 - F-speed *
ConfFull - Vapp target
*When we do a Flaps 3 landing weŽd like the A/THR to command Vapp tgt rather than F-speed. In order to make this happen we select Flaps3 in the MCDU even when we have manually inserted a Vapp.
Hope this clears things up.