Gordon et al.
Would the scenario of a loose vane about the shaft fit all incidents.
Re Lion, the vane rotated on the shaft as far as 22 deg (grub screw); the vane aligns with the airflow, but misreads due to the repositioned shaft under the influence of the balance weight. This also enabled the vane to be checked by maintenance without fault, because the vane was still free to move around the shaft.
With Ethiopian, the vane became completely free to rotate during takeoff, then the balance weight positioned the shaft equivalent to full up ? (down?). The vane remained free in the airflow, but without connection it was irrelevant. The shaft remained free such that the balance weight reflected the effects of ‘g’ at the end of the flight.
Have the ‘errant’ AoA vane units been found; loose vane, or no vane.