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Old 11th Nov 2011, 17:26   #101 (permalink)
 
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Rebuttal

Mr Optimistic said:
Quote:
Interesting reading but the strong inference must remain that the 3 crew at no time seriously considered that they were stalled and at no time applied appropriate inputs to attempt to address a stall. Can't see how yoke/aoa gauges are relevant. Perhaps they would have made a difference, we can never know,
First, ND input was tried (for not long enough) but it brought the stall warning back on. That may not be a good excuse but it is perhaps a REASON.

"We can never know" if an AoA indicator would have helped. And there, you've made my case, thank you. Likewise, we "can never know" whether-or-not seeing a yoke buried in his lap might have helped PFN come to a realization. In other words, you who insist that some of these things made no difference really have no solid evidence for those claims. Pure opinion.

Of course, there is no such thing as foolproof, but should we not err on the side of making the Airbus as "foolproof" as possible? Of course we should. Why shouldn't pilots have every possible tool in their box, given the many opportunities here for profound confusion?

Quote:
Originally Posted by DozyWannabe
Yes, the Airbus sidestick design drops the tactile feedback channel, but whether that is a big deal or not largely depends on your opinion
To which Clandestino offered:
Quote:
Opinion of certifying authorities is that it matters not.
Well sir, now that we have AF447, maybe they will reconsider, eh? Are certifying authorities always right the first time?
Where is the icon for 'pppfffttt!'?
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Old 11th Nov 2011, 17:47   #102 (permalink)
 
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Quote:
Originally Posted by MrOptimistic
Interesting reading but the strong inference must remain that the 3 crew at no time seriously considered that they were stalled and at no time applied appropriate inputs to attempt to address a stall. Can't see how yoke/aoa gauges are relevant. Perhaps they would have made a difference, we can never know, but they should not have been needed in any case. Dialogue articulating the pull-up inputs is clear enough on the transcripts so can't think anyone was seriously misunderstood for any appreciable period.

Had the situation finally been appreciated and the subsequent recovery hindered through lost time or absence of some instrument, OK. But it never got to that point.
Thank You. In all of the techno babble, "sim-geek", bovine scat, the fact remains that the crew saw something that convinced them to ignore a stall warning. Either they were incrediblly stupid, or incrediblly confused by what they saw, felt and heard. No amount of FBW, SS, automation, defense changes the fact that three qualified aviators flew the bird into the ocean. What I find disturbing is that the airplane (AB) was designed to prevent such an event, but failed.
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Old 11th Nov 2011, 17:59   #103 (permalink)
 
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Quote:
Interesting reading but the strong inference must remain that the 3 crew at no time seriously considered that they were stalled and at no time applied appropriate inputs to attempt to address a stall. Can't see how yoke/aoa gauges are relevant. Perhaps they would have made a difference, we can never know, but they should not have been needed in any case. Dialogue articulating the pull-up inputs is clear enough on the transcripts so can't think anyone was seriously misunderstood for any appreciable period.

Had the situation finally been appreciated and the subsequent recovery hindered through lost time or absence of some instrument, OK. But it never got to that point.
The lead up to the stall almost certainly had to result from mental processing overload on the PF, and a hesitancy to act on the part of the PNF.

I agree that none of the 3 in the AF447 front office seem to have acknowledged or verbalized a stall (According to the released transcript). I have to assume that once stalled, the experience was too far from their training to recognize and would therefore have had to be puzzled out on an intellectual basis for a successful outcome.

Mixing the discussion of yoke vs stick and presence of AOA is like mixing oil and water.
If you had ever flown with an AOA gauge, had observed one in various flight regimes and in the Sim, and had became comfortable with the veracity of the indication, then when the stall warning began to squawk, your eyes would be programmed to look at the AOA indication for confirmation, particularly when the airspeed is no longer available in front of you. As long as AOA is moving in response to control motions, the operational assumption should be that it is valid (operational assumption = bet your posterior on it).
If the AF447 crew had an AOA indication and had been trained to use it, the only valid explanation for allowing the stall would be a death wish or both pilots sleeping.
There is a world of difference between stall warning and AOA.
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Old 11th Nov 2011, 17:59   #104 (permalink)
 
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Quote:
What I find disturbing is that the airplane (AB) was designed to prevent such an event, but failed.
Let's be careful about the semantics lest somebody starts believing these words.

The aircraft is designed with the means to have prevented this event.

It is not designed with the pilot out of the loop.
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Old 11th Nov 2011, 18:12   #105 (permalink)
 
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Machinbird uttered:
Quote:
Mixing the discussion of yoke vs stick and presence of AOA is like mixing oil and water.
Sorry, Mr. Bird, I had no intention of conflating the two things. What I intended to say is that they both share the attribute of "might have helped, who knows?"

The rest of your comments about AoA indicator are spot on and exactly what I meant but didn't have the skills to say so.
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Old 11th Nov 2011, 18:14   #106 (permalink)
 
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Quote:
Originally Posted by Machinbird
And some people have very little grasp of the varied ways in which people gather and process information.

Clandestino
Quote:
There are strict demands how one who wants to fly and avoid getting killed flying has to "gather and process information". As I said: not everyone...
So, are you suggesting that the crew for AF447 were not properly selected....?
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Old 11th Nov 2011, 18:21   #107 (permalink)
 
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Cool

Hi,

Clandestino
Quote:
Problem three, which really is mostly limited to fora: Airbus control laws are difficult to understand for someone with just a passing interest in aviation. Those with dedication and capability can master them without giving too much thought to them. Bad news is that not everyone can be an airline pilot
So .. are the AF447 airline pilots or not ?

Clandestino
Quote:
This might lead the AF into believing that all of their crews would cope with the problem under any circumstances.
Heuristic ... the good choice for evaluate a problem ?

Clandestino
Quote:
He couldn't. No one flying FBW Airbus can know what exactly is his significant cockpit other doing with the stick. If it's such a big deal, why would it get overlooked by those allowing thousands of Airbi flying passengers commercially?
Heuristic .. again
Heuristic is a invite to disaster

Last edited by jcjeant; 11th Nov 2011 at 18:33.
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Old 11th Nov 2011, 20:17   #108 (permalink)
 
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Quote:
Originally Posted by Old Carthusian
Your artificial horizon will tell you if the plane is climbing or banking.
Certainly not.
If it was true AF447 would have landed at CDG.
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Old 11th Nov 2011, 23:23   #109 (permalink)
 
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The shoal continues to multiply. Gentlemen this accident is about perception and psychological factors. It is nothing to do with the machine. I have consistently mentioned 'Know your machine'. In my view, the flight crew didn't and here I have to break cover. In my view they were incompetent and unsuitable to be flying an aircraft - their lack of professionalism and disregard for the procedures caused an accident in a recoverable situation. In my view they were part of a culture that had developed in Air France based on arrogance and casualness. I referred some threads ago to the Clipper Skipper syndrome - pilots who could do no wrong and didn't have the skills needed. Some of you should go and read up on the Pan Am accidents in the 1970s. In my view Air France their airline cut training and ignored important aspects of flying - they also are culpable.
As for the arguments that the instruments are unreliable I have never seen so many straws being grasped in one go. Read the reports again - the instruments were functioning effectively. It was the flight crew who didn't know what to do. NO CRM, No SOPs, No UAS procedure just frozen incomprehension. A yoke wouldn't have helped here at all. NO training, No chain of command. This is a human disaster not a machine failure. We must be realisitic here this is a pilot failure brought on by poor procedures. This was not an extreme case - this was an unusual situation which could have been recovered and has been in other situations. AirTren talks about information when perception is the key. Why did the crew ignore the stall warning? Why did they ignore their reliable instruments? They were not up to the job - that is the real cause of the accident.
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Old 11th Nov 2011, 23:47   #110 (permalink)
 
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Quote:
Originally Posted by Clandestino
Right SS - full back, left SS - neutral. Do you understand why the aeroplane pitched down even with full back sidestick, full NU elevator and THS in heavy nose up position, increasing towards stop?
I doing ok Clandestino, thanks, Old Carthusian may now realize that instruments donít necessarily tell what the flight control inputs are Ö

Now for you Clandestino :
You are the Captain on AF447, as you enter the flight deck the stall warning stops, the pitch is going down.
  1. The equipment is a A-330, you donít know for sure which pilot has control and donít know which inputs are applied.
  2. The equipment is a A-310, you see the right seater with 2 hands on the control wheel to maintain it to his stomach for half a minute.
Which scenario do you consider the most informative for you ?
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Old 12th Nov 2011, 00:08   #111 (permalink)
 
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Instruments are more reliable than human perceptions Conf iture and I haven't changed my opinion one bit. Certainly not on the spurious irrelevancies that have been presented so far.
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Old 12th Nov 2011, 00:26   #112 (permalink)
 
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Quote:
Instruments are more reliable than human perceptions Conf iture
Who said otherwise ?
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Old 12th Nov 2011, 00:51   #113 (permalink)
 
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AirTren, retired F4 to name a couple. Those who argue that a yoke would have helped. By implication you yourself (and I do apologise if I have misread your posts) also seem to think that

"Old Carthusian may now realize that instruments donít necessarily tell what the flight control inputs are"

Instruments do precisely that because that is what they are designed to do.
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Old 12th Nov 2011, 02:06   #114 (permalink)
 
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To my knowledge those guys have never pretended that "Instruments are more reliable than human perceptions" but I will let them reply.

"Those who argue that a yoke would have helped"
I am positively one of them.
Note : I do not pretend it would have avoided the crash but I do pretend it could have helped to avoid the crash.

But it is interesting to read you, and I think we are here in a situation where you read what you think you read and not necessarily what is actually written :

My comment IS :
  • you may now realize that instruments donít necessarily tell what the flight control inputs are.
My comment is NOT :
  • you may now realize that instruments donít necessarily tell what the aircraft is doing.
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Old 12th Nov 2011, 05:01   #115 (permalink)
 
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Of course they did - go back and read their posts. You will find numerous statements on how the yoke was more reliable than instruments. AirTren goes as far as to construct a whole castle in the air about it. Retired F4 talks about the yoke being more reliable than instruments. I would submit his memory is at fault here.
Given the way the PF reacted a yoke would have made no difference - simple as that. The cause of the accident lies in the human factors and we may never know exactly what caused the PF to act as he did. However, your preference for a yoke is an irrelevance to the cause of the accident. It would not have helped because of the circumstances of the crew on that flight.
As for your final point my comment still holds. Instruments do tell you what the flight control inputs are. That is their purpose - to give a pilot a measurable and reliable indicator of his flight control inputs.
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Old 12th Nov 2011, 09:03   #116 (permalink)
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Old Carthusian - leaving aside SS/yoke arguments, I see a matter of some concern in your understanding of instrument flying. You have no 'career' information in your profile, so I have to conclude you are inexperienced in Instrument flying.

There are two glaring inaccuracies in your recent posts that I do not wish other pilots to absorb:

1) Post #69 "Yes by looking at the instruments. An input produces a certain pattern on your instruments and you can understand what your aircraft is doing" It might not and you cannot always.The instrument reflects what the aircraft is doing after the input and that may well NOT be what you intended. See AF447?

2) Post #76 "Your artificial horizon will tell you if the plane isclimbing or banking" It will not. It will, of course, certainly tell you if your nose is high or low. Perhaps you do need to re-read the AF447 report? Then tell us what PNF's EADI showed in terms of 'climb'?

Lastly, I would point out that no-one knows what PF's instruments were displaying anyway? We are (naturally) assuming they were functioning correctly - and they probably were, but we do not know.
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Old 12th Nov 2011, 09:09   #117 (permalink)
 
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Quote:
Old Carthusian (bolding by me)
Of course they did - go back and read their posts. You will find numerous statements on how the yoke was more reliable than instruments. AirTren goes as far as to construct a whole castle in the air about it. Retired F4 talks about the yoke being more reliable than instruments. I would submit his memory is at fault here.
That is a hard accusation of you, and a personal one. If you make such peronal accusations, you should at least quote where i did so. Lets find out whose memory is at fault.

As we exchange personal genialness, i would assume that your personal knowledge concerning flying itself seems limited, and the knowledge concerning aerodynamics and other vital aircraft dynammics is not existent.

Your analysis concerning the human factor stands well and was not doubted neither by myself nor by a lot of other posters, but it does not stand alone. There are contributing factors to any accident iīve known so far.

To close his eyes and cry down other voices like you do here with my oppinion by disqualifying my memory places you as the first ever poster on any forum on my ignore list.
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Old 12th Nov 2011, 09:47   #118 (permalink)
 
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Old Carthusian,
Quote:
Instruments do tell you what the flight control inputs are. That is their purpose - to give a pilot a measurable and reliable indicator of his flight control inputs.
But on Airbus, the F/CTL ECAM page is not normally displayed in the cruise. A pilot would have to deliberately select that page.
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Old 12th Nov 2011, 10:11   #119 (permalink)
 
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BOAC
Of course artificial horizon will tell you if you are climbing - what do you think the gap between the horizon line and whatever symbol is used for the aircraft means? Yes it means your nose is raised but it also can be used to ascertain that the aircraft is climbing. OK here I am guilty of simplfying a bit (which is a problem for me, I value brevity and expect others to understand this.) but then so are you - it serves both purposes very adequately. What it will not tell you is your rate of climb, you need the altimeter for that and if you quoted in full you would have included my mention of the the altimeter.
The instruments are there to provide an indication of the results of your inputs. Without them you are very much guessing every flight and they are certainly more reliable than your personal impressions. As for AF447 I suspect that BEA knows pretty much what the PFs instruments were reading - they may not have chosen to release the information but they do have it. Everything released though points to a psychological reaction by the PF which was not dealt with adequately by the captain or PNF. It does not point to any problem with the aircraft. Your final point is a straw man argument - if there is no reported problem with the PFs instruments then there is no reason to impute a problem.
Retired F4
Memory - a very unreliable thing especially were flying is concerned. It's nice to be so assured about every flight you've participated in but me I cannot. I have to check and then maybe I can summon up a reliable memory. If I disqualify my memory then I also have to mistrust your memory.
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Old 12th Nov 2011, 11:43   #120 (permalink)
 
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Old Carthusian,
Quote:
Of course artificial horizon will tell you if you are climbing - what do you think the gap between the horizon line and whatever symbol is used for the aircraft means?
Isn't that exactly the same error that PF also made?
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