Originally Posted by
HarryMann
Maybe but less likely than an AoA disagree ?
Not really, the highest likelihood would be of a disagree. To have failures and not have a disagree would come from multiple failures of identical types and outcomes. Now that more or less happened at perpignan IIRC but it may have still just been a single sensor failure, where 2 out of 3 vanes froze position literally due to servicing which didn't protect the vanes from water ingress. At altitude the vanes froze, and presumably the correct vane was voted out by the two stuck vanes. The vane is pretty reliable, but I replaced a couple on one B737 in fairly short order.
The conic-static pressure type on the westwind is reliable...