Originally Posted by Clandestino
Do you have any idea what's the difference between dynamic pressure at 60 KEAS and 330 KEAS, everything else being identical?
Clandestino. This is all very irrelevant to the accuracy of the AOA vane as far as being useful. The AOA transmitters only send out an angular measurement. Nothing that is rocket science.
If the aerodynamic forces on the vane are enough to override the inherent friction in the mechanism, the vane will swing to very closely align with the relative wind. At very small AOA relative to the local air velocity vector, the inherent friction may be sufficient to create a small error provided the velocity is just above the 'come alive' speed. But in reality, once a vane comes alive, it is pretty accurate.. As I mentioned earlier, 'come alive' speed is typically in the 15-20 mph range. By the time you get to 60 knots, dynamic pressure is about 12 times higher than 'come alive' speed. More than sufficient to point the vane with extremely high accuracy. (much more than you need for basic stall warning)
The primary mode of failure that I've seen has been sticky transmitters due to contamination of the bearings and physical damage. They are really interesting gadgets. If you haven't already done so, find an opportunity to handle one.