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Old 14th Sep 2012, 11:55
  #69 (permalink)  
Clandestino
 
Join Date: Feb 2005
Location: Correr es mi destino por no llevar papel
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Originally Posted by Hetfield
Yes, but totally different scenario.

In both cases, like some others, a goaround was misshandled. A typical A300/310 issue (have been there, got the t-shirt).
Correct... it was the issue of not realizing the autopilot is on and it doesn't disconnect if force on yoke is applied when on automatic ILS app below certain radalt (this was DGAC required modification in order to certify 300/310 for autoland ops) so folks got aeroplane severely mistrimmed by fighting the autopilot. Chalk one up for autotrim.

It is interesting how folks in the heat of the battle forget to trim manually. IIRC, Karair pitch excursion somewhere around 1989 was stopped at 40° ANU as PF tried to relief the forces and trimmed, thereby kicking the AP out.

So much for this digression.

Originally Posted by Alex757
but surely ... if the throttles moved (like a boeing) the crew would hold them until 80kts (or is it V1?) and would instantly recognise a power reduction
No. Old red herring that keeps returning. You can even find YouTube videos of old pilots spouting this, only proving how lucky they were never to have engine control failure during their careers, for surely, smart they weren't.

Originally Posted by ECAM Surprise
There was also an airbus case I believe.
Very probably there was, however I wouldn't believe anything without proper reference. Maybe it is just me.

Originally Posted by gerago
Remembered a stick and rudder hero at my previous outfit who decided to fly manually with A/P, A/T off.
Manual flight with autothrottle/autothrust active is strictly prohibited at my outfit so no confusion about it being on/off. I think it's a good thing.

Originally Posted by noclue
Having no idea of "airbus laws" can someone briefly explain this "alpha floor logic that they have??
Alpha floor is generic term for automatic high power command when AoA gets way too high. Even 737 NG have it and on them it's called...."Alpha floor".

Originally Posted by Bigmouth
Taking your hand off the throttle while hand flying is a mistake made only by pre-solo student pilots and rank amateurs.
Blasé aerosexual jetpilots too.

Originally Posted by Gretchenfrage
It's almost like groundhog day!
Sure it is, since some folks building their theories of advanced flight control architecture, found them on spectacular misunderstanding of basic flying principles and are unable to take subtle hints their notions are so at odds with reality, they only have some limited entertainment use. As explicitly pointing them they are somewhat clueless would go against RoE, I guess we have to live with it.

Originally Posted by Gretchenfrage
no, it has nothing to do with the AB dead stick/lever philosophy, because even the Turkish managed to dump their 737 ..... etc. blah, blah ..
It wasn't just Turkish. There are thousands of Airbi landed uneventfully every day, as there are hundreds of pilots throughout the history neglecting to monitor their airspeed. Nothing to do with flight instruments or flight controls architecture.

Originally Posted by Gretchenfrage
How can you try to defend a design flop by pointing to morons producing an accident with another design???
What flop? What morons? In real world, airliners are stil flown by human beings and, unlike machines, they tend not to perform equally every time. Just because a pilot makes "stupid" mistake it doesn't qualify anyone, especially not some participant in anonymous internet discussion, to label him as "moron". Overall performance is a pointer of how one might act when thinks go pear shaped, not guarantee. Clueless pilot might get lucky and fly throughout career without scratching his aeroplane and knowledgeable and competent pilot can be faced with task far beyond his capabilities early in his career. Of course, all Joe Public sees is smoking hole and wants to blame anyone for that. Easy if pilots are foreign. Even easier if Airbus is involved as all the false stereotypes about computers surface.

Originally Posted by Gretchenfrage
With the same argument we can abolish ABS and ESP in modern cars by showing that there are some other morons who were able to crash even highly equipped cars!
Nope. If pitch feedback is comparable to ABS/ESP, then Airbus is waaaay beyond it, nothing like we have in the cars yet.

Originally Posted by Gretchenfrage
Such argumentation is not only puerile, but even cynical.
Argumentation you have presented is straw man. Argumentation Airbus needs not control feedback to be safe might be even sarcastically delivered, yet it's true.

Originally Posted by Gretchenfrage
To my belief controls with feedback represent an additional protection in modern cockpits.
Yes they do, but they have synthetic feedback to prevent pilots from ripping their wings off or killing their passengers Synthetic pitch feel is not designed to be speed cue, its use as such is incidental and unapproved and anyway, there were numerous incidents and accidents where unusual feel or displacement of controls provided no cue for hapless crews. Airbus has G protection to deal with overstress risk. Loss of it puts it in config similar to loss of pitch feel on "conventional" aeroplane. A bit more difficult but definitively manageable even for the subpar pilot.

Originally Posted by Gretchenfrage
But if you look at feedback-controls through the above optic, namely as an additional protection, it makes absolutely no sense to abolish them.
Of course. Problem is that this proposed optic is largely based on total misunderstanding how manual instrument flying works in real life. Pilots sets pitch and power, trims out, checks for performance. If it isn't what is expected, pitch and power are adjusted, forces trimmed out, performance checked. So on and so forth until rollout. Control position is just demand, not delivery and every clue about aeroplane behaviour is taken through visual channel. That's why those officially tasked with recognizing whether the design is airworthy have certified A318-A380 even if it has no synthetic feedback or moving thrust levers.
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