Dagger Dirk:
I think that UNCTUOUS was inferring that the water present in the static lines froze and expanded in the lines at height - blocking the static line and locking in the static pressure. That can happen as a function of:
a. water pooling (flowing from another area after the climb and due to angle of incidence in the cruise)
b. thermal soak (cooling time - explaining why it took around 3 hours)
Ok, why not but suddendly like that? And once it is frozen, after around 3 hrs, why would the static lines just became clean all together after few minutes, and why maintenance would not discover any problem (beside the pitot-probes) once grounded?
I'm much more prone to believe that this is an explanation in order to twist the sequence and legitimate the following:
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If, in consequence, the sudden ADIRS disagreement precipitated an autopilot disconnect, then it's possible that a loss of control ensued (due to Alternate Law coupled to heavy handed inputs at a height at which pilots aren't used to hand-flying anyway). Very few pilots would have hand-flown at FL300 and above.
Well, at FL350, the aircraft is flying level and all Airbus are flown in direct law without much trouble (ask Lemurian, it is like a 737). They have even been certified like that, before introducing the various level of fligh envelope protection. Not a single report from any previous freezing incident included the quote: "we were left with an uncontrolable aircraft impossible to be hand flown because A/THR and AP disconnected"...
If pitch protection is still in force in Alternate Law, during an upset it may well work AGAINST a successful recovery. Anybody who's practiced unusual attitudes knows that once a jet's nose drops significantly below the horizon at speed, you are then battling to not exceed VNE/max Mach by a wide margin.
Here is the main point. But sorry, pitch protection disengaged in ALT2. Moreover, we already know the altitude (FL350) and speed (cruise) at 0210, it was sent by the positional report few secs before the first ACARS. The aircraft wasn't at all in an uncontrolable attitude at this point.
Success there is tied to generating drag via g, after (but not whilst) rapidly finding wings level then pitching back up to the horizon (and using idle thrust/speedbrakes to control the rate of speed increase). All this depends upon having a valid attitude source. If you don't, then the LOC becomes terminal due to disorientation. If pitch protection affects the rate at which you can pitch, then likewise you are probably going to exceed VNE by a VERY wide margin.
Sure, but nobody previously lost control, just maintained pitch and power and waited until the speed come back. In your scenario, the aircraft is starting to break appart... but, sorry, she didn't and it is now confirmed as a fact. Moreover, the area searched so far was a 80 km circle around her last position and they didn't found any wreckage at the botom of the sea. => she didn't crashed around this point.
That's what likely happened in the 4 minutes immediately prior to the final ACARS msg. Any less rapid a sequence would have permitted at least a Mayday call to have been transmitted.
Who told you that they didn't tried to transmit a Mayday?
Nobody heard from them on radio/statelite. Their last contact with Brazilian ATC (0145 and few secs). Then, the tried, without success, to contact Dakar at 0201 (the call was logged). Dakar ATC wasn't informed of AF 447 flight plan from the Brazilian ATC... go figure, it takes the Spanish ATC to give an alert at 0615 utc. Moreover, the BEA presented the fact that the closest aircraft (AF, IB, LH) had all experienced transmition problems in this area at the same time. None were able to use their VHF.
ACARS are relying on SATCOM. There is plenty of reasons why SATCOM could stop transmiting. One is a double engine failure (e.g. engine icing or stalled if they lost control).
Last point from the BEA conference: they underlined that
nobody recieved any AF 447 report of "strong turbulences" during this flight. The 0145 ATC contact was her last. Neither ATC or Air France (as I suspected it from the first Air France conference) recieved anything.