Lonewolf50
For Graybeard and about AoA Probes and indications
Graybeard, in re "better" AoA indicators. I'll suggest to you that the US Navy has been using one "better" (actually, I doubt it's any better) from before I started flying which functions reilably at airspeeds below 60 knots. (There is one on the T-34C Trainer that works as you describe ... a weather vane in the horizontal plane. See also AoA probes on various Navy jets).
I don't think it's the probe that's the issue, but a software decision on signal processing. You could do what you need to (no stall chirp on the ground) with a WoW switch (already have one on the bird, yes?) without artificially clipping the AoA signal when in flight.
Your comments, sir?
The real measure of AOA is degrees, not knots, of course, although everybody has been shouting for a Stall Warning below 60 knots, not a specific AOA.
I don't have the numbers, but it appears that onset of stall of the A330 at that MAC and flap is less than 20 degrees. The report shows AF447 achieved AOA in excess of 40 degrees, double the onset of stall. How much AOA does it need to measure, 90 degrees, 120 degrees? What's the point?
You have to balance Stall Warnings in extremely rare events with far more common nuisance stall warnings, in order to maintain confidence in the system. In fact there was no doubt a point in the zoom climb to stall that airspeed was near zero, and the AOA vanes would fall with gravity, probably showing a negative AOA.