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Old 25th Oct 2013, 17:55
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DonH
 
Join Date: Oct 2013
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Chris Scott - in your response to Clandestino, I concur with your remarks. I think quoting and responding has its merits and offers succinct thinking and keeps posts to reasonable lengths!, but it is very important to retain the context of the original remarks being critiqued. Sometimes there is a historical dialogue going on and brief quotes which appear out of context to others are really in context in "the long line" but I thought yours and perhaps one other's were a taken a bit out of context. I think reference-links to actual Post # being quoted so others could refer back would resolve the matter, and others can make up their own minds regarding the critique offered.

As regards the matter at hand and as I know you know, whether an actual pitch-change and altitude loss or purely an indication issue, (which this was), one never responds swiftly in a transport aircraft, particularly at cruise altitudes where aerodynamic damping is much lower. The argument that the roll was PIO and that the pitch up was a response to the indicated loss of 300ft are both defeated by subsequent occurrences - the first because the more-sensitive roll was brought under relatively quick control, and second because, once the 300' "altitude loss" had been "regained", the PF kept pulling.

The majority of stick positions is, by the data, "stick back". As said many times, I think there is probably something to the stall warning NCD matter but, as you have observed, it isn't a C-150 where the little piece of metal is permitted to flip forward due to reduced airflow at it's point of installation setting off the approach-to-the-stall buzzer! The designers had to resolve the matter within purely digital systems to avoid the greater problem of false warnings at critical times, and, rightly in my view as an experienced A330 captain, concluded that no crew was going to stall the airplane and keep it there such that the AoA was so great, (45° +), as to actually render the pitot's unserviceable, (entry angle too great - no speed indication, ergo speed < 60 = NCD).
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