Hi DozyWannabe,
If the manufacturer of the AoA vanes specifies that their output is unreliable below 60kts, how else are you supposed to implement the system?
You simply make the stall warning invalid below 60 kts AND on the ground (to prevent false nuisance stall warnings during the early take off roll).
However, when you are airborne, if the angle of AoA sensors think you are stalled and even if you have less than 60 kts indicated forward airspeed - then you are definitely stalled. Therefore remove the 60kt logic once airborne.
@ Owain Glyndwr
but I can't find any reference to a similar feature in Alternate (possibly worked off stall warning).
A320 FCOM OP-020, Flight Controls, Alternate Law
"At the flight envelope limit, the aircraft is not protected, i.e.:
In high speed, natural aircraft static stability is restored with an overspeed warning
In low speed (at a speed threshold that is below VLS), the automatic pitch trim stops and natural longitudinal static stability is restored, with a stall warning at 1.03 VS1G."