Hi Gundernak, The AoA meter indicates the angle of the un-flapped portion of the wing to the relative airflow. When the flaps are deployed, a pitch down is required to maintain level flight. So the un-flapped portion of the wing reduces its AoA ( which helps to prevent a wing-tip stall.)
The AoA of the flapped portion of the wing increases, because the trailing edge is lowered, and that part obviously stalls first.
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