PPRuNe Forums - View Single Post - AF447 - French prosecutors sends AF to court for negligence
Old 20th Jul 2019, 10:53
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sonicbum
 
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Originally Posted by tdracer
I don't want to turn this into another Airbus/Boeing bash fest, but I suspect there is some cause/effect due to the pronouncements from Airbus (and others) that 'it's impossible to stall this aircraft'.
In an emergency, the human mind may not remember whatever qualifications may have been put on that statement - e.g. 'in the full up control mode'. He just remembers 'impossible to stall'.
With that in mind, if his brain was telling him it's 'impossible to stall', holding the stick full back while the aircraft drops like a rock (even with the "stall stall" warnings) is somewhat easier to understand.

Tell the pilot that there are anti-stall protections to 'help', but don't tell them they can't stall it because in the right circumstances, they can stall it.
Airbus never stated that any FBW aircraft is impossible to stall. They have always emphasised the fact that flight control protections are there to prevent entering a stall, i.e. exceeding the stalling AOA. If those protections are not available due to a flight control system downgrade, then it is obvious that the stall AOA can be reached and exceeded and this is exactly what thousands of pilots learn during their type rating and it has always been the same for the past 30 years. If a pilot's muscle memory connects "FBW = no stall" and nothing else, then there are issues that need to be tackled somewhere within the SHELL, which is basically what has happened in the past 10 years since the accident, by increasing crew exposure to high altitude hand flying in alternate law, stall recovery and unreliable speed management. Airbus sells You a product, tells You how it works in detail (that is not always the case in the industry apparently) and gives you support to build training programs. They do not have a crystal ball and foresee how each and every airline pilot will react to any system anomaly, as this is part of the operator's duties to ensure proper guidance is given and maintained trough a proper system of recurrent training and checking.
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