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Old 28th May 2011, 06:55
  #644 (permalink)  
SoaringTheSkies
 
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do we have a good explanation for the elevator trim setting?
would it have been obvious to the pilots (prominent / highlighted display?)

I'm still very confused about this.

From reading what is available, I believe that "Pilot error" will very likely be declared the accident cause. I'm not sure I'll necessarily agree, albeit "perfect pilot" would probably have saved the day.

Correct me if I'm wrong, but it seems to me that with greater automation comes an ever larger pile of sh*t that the automation systems place on the pilots hands if they decide to give up trying to be smarter than a human.

Automation systems basically handle pre-defined situations very well. Whatever scenario the engineers, flight test crews and probably even accident reports came up with goes into the system and becomes then part of what the system can handle. So far so good, but at the fringe of this, the resulting situations become increasingly complex to understand and manage.

There are a few things that need to be questioned:

Why is the stall warning silenced at indicated airspeeds below 60knots? Surely because whoever designed the system decided that, at an airspeed below 60knots, something is so terribly wrong that you would have noticed, possibly the airspeed being unreliable. However, as we all know, a stall has absolutely nothing to do with speed but is a function of AoA only. Why gate the warning with anything if you have consensus of the AoA sensors?

Is there no stall protection outside of normal (alternate 1/2?) law on an AB? Stick pushers have been around for many many decades, they are simple technology and rather effective. They need one input (AoA) and do one thing (make you pitch down). I know the AB have a much fancier system when the protections are effective, but do they really leave you entirely on your own when you drop out to alternate or direct?

[edit] and one more thing:

MountainBear
I think there is a temptation to expect the captain to ride on his white steed from the bunk onto the flight deck, manfully throw the stupid PF out the door, and heroically wrestle the plane to safety. That would make for a thrilling movie plot but it doesn't reflect the way CRM actually works.


the public expectation is trained by Hollywood movies, so this seems to be EXACTLY what they would have expected to happen. After all, some German media STILL report that the PILOT was not on the flight deck!!!
Utter BS! And as we see, when the CPT came back to the flight deck, he was just as confused as his two FOs. That's why I got rather annoyed about those fellows who claimed that they'd be in their left seat in every critical phase of the flight. It's a judgement call and this crew decided that the phase ahead was not going to be critical. Little they knew, but that's a general fact about what we call "future".

Last edited by SoaringTheSkies; 28th May 2011 at 07:04. Reason: additinal response
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