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Old 17th June 2011 | 14:00
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Lonewolf_50
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That same Air Caraibes report also said that at the time of the beginning of the anomalous air data, the indicated altitude rapidly dropped 300 ft (presumably due the lack of a vaild Mach number to correct the static pressure (? ) the BEA has already told us that with no vaild M, the stall warning system uses a value near zero...)Maybe the PF was reacting to that, admittedly 300 ft isn't much, but I suspect it looks a lot on the tape, and it would have been rapid. Perhaps this is the trigger we've been looking for.
Man-machine interface. Is the unreliable M related only to airspeed/pressure sensing, or is it also related to a TAT sensing anomaly?
mm43
I doubt if there is overly much difference between the initial FDR printouts of the Jetstar VH-EBA UAS incident and those recorded by AF447. Have a close look at what happened to the TAT, SAT and CAS traces and similarly to the altitude when the Mach correction wasn't available.
Probably worthwhile bearing those traces in mind when discussing the initial upset.
How can BEA confirm or determine if the ice and pitot tube interaction was accompanied by an ice TAT probe interaction?

I will guess that a trend line from "X" minutes prior to the event could show where Temp anomalies are or aren't likely. The recorded cockpit briefing about temperature not developing as planned/forecasts may be of no moment ... or maybe a clue pointing to TAT readings sensing beginning to degrade as Airspeed sensing began to go wrong?
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