Even more ridiculous, Boeing offered a second source of truth option, but marked it as an upcharge, which the airlines in question rejected. "No thanks, no need for a second AoA sensor, one is none is probably fine!"
Additionally, two feels like a really strange number. I would think three for a tiebreaker would be standard for any sensor with that much impact (no pun intended).
Yes, two would be very ill-advised. I think there was some incident where a plane had only two pitot tubes and of course this caused problems. Or... I may have simply misremembered pitot tubes instead of AOA sensors in the Boeing case.
