BOAC;
Yes, the Aeroperu had the statics taped over with clear tape while the airplane was washed. The Birgenair 757 pitot loss cause was undetermined but there was a theory that mud-dauber wasps had built a nest in one of the pitot tubes. The current issue is disconcerting for sure. Because of the autoflight system depth of component and software integration the effects can be very distracting and initially difficult to assess while the airplane's warning systems settle down. Cascading failures can be very distracting, but that is not the primary issue here. The key is to do nothing and change nothing because the airplane was just fine moments before the event. The issue here is surprise and confusion not the loss of data and that is not a situation which will inevitably lead to a LoC.
GB, not sure who you're asking re "the pilot seeing erroneous airspeed" and re the point you're missing. I don't recall a lot about the 1990 incident and what we did but if it was my post your asking about, the point you're missing is obvious I think - the unreliable airspeed problem was essentially a non-event. We determined which indicator was correct using the Standby ASI and we flew the airplane to destination without further incident.
I don't recall any drills in the books which called for switching ADRs as, at the time, there was no such thing as an unreliable airspeed. We just used our heads and made it up as we went and it worked just like it should. The Birgenair and Aeroperu accidents occurred in 1996 I believe.
mulder:
I would think that the stall warning and IAS would immediately be suspect. In fact a stall procedure at this stage might even be unsafe
In my opinion, you are correct. "Respect the stall warning" must be understood as meaning, respect "legitimate" stall warnings. We expected (but did not get) an overspeed warning when the captain's ASI exceeded the barber pole, (Max operating speed). We would have ignored the overspeed warning in that case.