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Old 11th Nov 2011, 15:07
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airtren
 
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Originally Posted by DozyWannabe
...
Based on historical data, we have incidents where inappropriate backpressure following UAS has occurred on aircraft equipped with interconnected yokes and independent sidesticks, most of which have led to an airframe loss. We also have historical data that proves lack of interconnection is no barrier to recovery (specifically the other 30-or-so A330/340 incidents which did not lead to a crash). That suggests to me that any round-robin discussion of interconnection vs. independence is not relevant to the case at hand, which is why I'm not going to get involved any further there.
First, this paragraph creates a wrong equivalence, by generalizing and taking historical/statistical data out of the very specifics of the context of each case.

Then, the paragraph is diffusing, or blurring the main point from the "visual contact", and/or "virtual secrecy" of the placement of the A330 SS, which is the problem pointed out by several posters, to "interconnection" and "independence", which no-one mentioned other than you.

Addressing the "visual contact"/"virtual secrecy" would be a lot more helpful in converging on this discussion....

...The Airbus engineers ran the sidestick design past the pilots (at least one of whom was the most respected safety pilot in the world at the time) and got approval.
It's "the placing of the SS" that makes visual contact with it impossible, not the "SS". The paragraph is another example, mentioned before, of extrapolating or extending one problem of a mechanism, to the entire mechanism, or system, which creates the road blocks of being able to converge in this discussion.

...while arguing over whether having a badly-positioned yoke in front of him might have made the PNF react more decisively, the thread is missing the point that neither of the F/Os at any point seemed to acknowledge that they were in a stall,...
...while the more decisive reaction is emphasized correctly, the paragraph is missing the point that an earlier and more effective correct action of the PNF could have prevented the Stall, during approach.... or could have made the recovery from Stall possible....

.... Air France was routinely sending up 3-man crews, two of whom had no manual handling instruction at high altitude, in a type that they were aware had a known problem with the pitot tubes that in a worst-case scenario would force the handling crew into handling the aircraft manually at altitude. That's almost priming the system for an accident eventually, and no amount of debate over automation or interconnection will alter that fact. Whether Air France were alone in this practice (I suspect they weren't),...
Of course they weren't, ....

What Air France, or others did, while being "a cause", is in fact, also "an effect".

Why did they do that? what is the cause? what put them at ease, that it is possible to do that without significant risk?....
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