The contents of those links is the nearest I've seen to a credible explanation for AF447. To understand how a competent well-trained crew, used to avoiding enroute severe weather, could be sucked into a scenario, you need to entertain an insidious technological circumstance having sneaked up on them - for a TOTAL surprise - full of uncertainty and confusion. This scenario at those links paints just such a picture.
What's more, flying through layered thick CirroStratus and quietly accumulating ice crystal build-ups (uniformly) in the pitot heads isn't in any way beyond belief. In fact it accords with exactly what was known about the major deficiency of that mark of Thales pitot head. Its pitot heat was unable to cope with prolonged exposure to thick Cs cloud - which is composed of super-cooled ice crystals. The pitot heaters were thermally overrun and the Airbus automation disguised that fact, sufficient to allow an autopilot diisconnect, several system alerts and a flight control degrade at speed and height. Sometimes that's all it takes to induce an LOC. It's not as if there weren't numerous precedents with exactly the same type build-up, even though lacking the eventual onset of a terminal development. At night, above the thick thunderstorm clouds of the ITCZ made the fatal difference.
So I'd urge you to disregard this input below as a total red herring (for all the above reasons)
Why do we assume, that the icing up of the pitot-tubes and the subsequent automatic system-reactions contributet to an drastic increase in IAS followed by desaster?
A few thoughts to augment my question.
Would it be logical to assume, that icing took place not only within the pitot-tubes but as well on other critical aircraft parts/ surfaces as Flight-controls?
Would it also be logical, that the heated pitot-tubes would be the last parts being affected by icing due to the heating of those?
What would that weight increase be, how would it effect aerodynamic lift and how much would it increase aerodynamic drag?
How much elevator trim would be necessary to counter those effects given a stable speed?
How much would the AOA increase to maintain level flight?
How much power is availabel at the given altitude to maintain straight and level under such icing conditions, or even accelerate, and if that is possible, how long would an acceleration take?
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