reallynoidea:
What would allowable rudder deflection be if, before the double failures, airspeed was 'indicated' to be very low. Would that allow full rudder following the SEC failures? Or is there logic that only allows min deflection once limiting is activated, until slats deployment?
I don't have detailed enough information to answer this, but it is an idea that has been floated here. I (and probably others) also brought up the idea of working through things from the probes to the ACARS msgs vs. starting at the ACARS msgs and trying to work back to what could have caused them.
My question at that point was if you could reach out and slap a piece of tape over the pitot tubes what affect would this have on the instruments in terms of IAS, AOA, ALT, and any other inputs to the ADIRU's, and then how would the FCS react.
The bigger question being how the FCS system would handle what may have appeared to be a rather sudden change in these parameters. There are various protections for different conditions that could come into play if the FCS was convinced that condition existed. On top of that you have the possibility the faulty inputs cause the FCS to fail what could be good components.
Previous A330 (and possibly since) upsets tend to make this seem like a recoverable situation, but add the weather, darkness, and any other number of factors on top of this and you might have a situation that is simply to complex to handle in the available time.