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AF 447 Thread No. 7

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AF 447 Thread No. 7

Old 11th Nov 2011, 07:13
  #81 (permalink)  
 
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Originally Posted by gums
Those that have not flown FBW still need to realize that even in the Airbus "direct" law, the computers still modify the control surface deflections and deflection rates. To wit from FCOM manual I have:
So let's get to the point.
Is it your opinion the pilots were trying to do the right thing but the flight control computers, "HAL" if you insist, grabbed their arm and didn't let them?
If so, please point out where, as it would be a serious factor in AF477 and definitely should be discussed here.
Otherwise, maybe a separate general FBW thread would be a more fruitful place for a discussion of these matters?
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Old 11th Nov 2011, 08:38
  #82 (permalink)  
 
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Quote:
Confiture
2 PNF knew the PF was making inputs - Did they know which inputs he was making ?

Answer Old Carthusian
Yes by looking at the instruments. An input produces a certain pattern on your instruments and you can understand what your aircraft is doing.
Would you explain yourself in relation to the timeframe starting from 02:12:45?

Retired F4

Stick was full left, aircraft was banked to the right, how do you know by instruments, what kind of inputs are made by the guy in the dark 1 meter away?

Answer Old Carthusian
Retired F4
Both the PF and PNF have displays with the same instrumentation on them. Your artificial horizon will tell you if the plane is climbing or banking. You derive your rate of climb (or descent) or descent from your altimeter. Your bank rate from your rate of turn indicator. These are reliable and accurate instruments. They are not affected by UAS. Anyone who doesn't rely on their instruments ends up in a dangerous situation.
Why not answer my question, which you yourself raised with your answer? We are not talking about instrument flying and its carrying water to the sea to try to teach me how it is done. All of my 3.336 instrument approaches where handflown from start to end and successful terminated. Most of them in german wx conditions, not under the sun of california.

The discussion is about recognizing actions (not outcome) of handling flight control inputs in a non normal situation like AF447 was in.

I did lots of instructing in the backseat of the F-4. Our sticks had been interconnected and i could feel through critical maneuvers. Let us look at stall approaches, where a wrong flight control input lead to departure. On the stick the wrong input could be felt and corrective action could be taken immidiately and thus departure prevented, whereas on the instruments the faulty input would show later, when the faulty input had already lead to departure and uncontrolled flight. Better to be one step ahead than one step behind.

In the case of AF447 at 02:12:45 the PNF and the captain had been both aware of the right bankangle and gave instructions to the PF to correct that bank as they could not observe any action of the PF to correct this bank on the instruments. In reality the PF was aware of the same fact and told them, that he already had full left SS without success. That information was vital as it showed, that correction with aileron alone did not work and helped the captain to refocus on solving the bank problem with rudder input. It took considerable time to unmask this information and it was not visible on any kind of instruments.

DW
The precise position of the stick is considerably less important than being able to work out that the stick is not where it should be. Once that is ascertained, then the only logical recourse is "I have control".
It can be assumed, that had the PNF took control of the aircraft prior receiving this information at 02:12:45, that he as well would have used aileron firsthand and would have lost valuable time as well.

I never said, that the SS should be replaced by a yoke, but i do not turn a blind eye to the fact, that in this stressfull situation the awareness of the crew concerning the behaviour of the aircraft in relation to the flightcontrol inputs of the PF was totally lost, that the captain was not able to grasp the situation when he came back to the cockpit and that the mentioned timeframe starting at 02:12:45 is a master example for the lack of direct feedback. Not that this is the only situation in these horrible 4 minutes, there are others as well. It is only a question of perspective.

Last edited by RetiredF4; 11th Nov 2011 at 08:58.
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Old 11th Nov 2011, 10:04
  #83 (permalink)  
 
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Originally Posted by CONF iture
... or 02:11:55 when the pitch is 10 deg below horizon ... where is the stick Old Carthusian ... !?
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?

Originally Posted by Retired F4
In the case of AF447 at 02:12:45 the PNF and the captain had been both aware of the right bankangle and gave instructions to the PF to correct that bank as they could not observe any action of the PF to correct this bank on the instruments. In reality the PF was aware of the same fact and told them, that he already had full left SS without success. That information was vital as it showed, that correction with aileron alone did not work and helped the captain to refocus on solving the bank problem with rudder input. It took considerable time to unmask this information and it was not visible on any kind of instruments.
Do you understand why the crew had what you call "bank problem"?
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Old 11th Nov 2011, 10:38
  #84 (permalink)  
 
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Clandestino
Do you understand why the crew had what you call "bank problem?
I do.
But please tell me your oppinion and how it would influence the discussed matter concerning recognition of correct or incorrect SS input as discussed.
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Old 11th Nov 2011, 10:41
  #85 (permalink)  
 
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Retired F4

I would hesitate to compare an F4 with an A330.
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Old 11th Nov 2011, 10:42
  #86 (permalink)  
 
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Originally Posted by Retired F4
I do.
But please tell me your oppinion and how it would influence the discussed matter concerning recognition of correct or incorrect SS input as discussed.
Could you please provide your explanation behind "I do"? Methinks that therein lies the problem but I wouldn't like to waste bandwidth by going tangentially.
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Old 11th Nov 2011, 12:05
  #87 (permalink)  
 
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Clandestino
Could you please provide your explanation behind "I do"? Methinks that therein lies the problem but I wouldn't like to waste bandwidth by going tangentially.
http://www.pprune.org/tech-log/46839...ml#post6799108

And feel free to PM me, that way we may waste time, but no bandwith.

OldCarthusian
Retired F4
I would hesitate to compare an F4 with an A330.
I would too, therefore i was not tempted to do it.

Last edited by RetiredF4; 11th Nov 2011 at 12:17.
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Old 11th Nov 2011, 13:18
  #88 (permalink)  
 
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Originally Posted by Old Carthusian View Post
I am afraid you misunderstand the situation - it is not about information transfer it is about information interpretation....... etc, etc...
Your reply to my post, the wrong references or repeats of my text, show that you dont see, cant see, or not want to see what I pointed out.

With the current location of the SS in the A330 cockpit, and lack of ability to have visual contact with it, it is not possible to a PNF and NF Captain to ascertain with good precision the SS position, and PF's actions on the SS. Several suggestions of resolving this without replacing the SS with a yoke were made even on this Forum NO, it is not the use of instruments, which is wrong for reasons I will not repeat.

From a system architecture perspective, the cockpit is a critical system application, and in such an application having a virtual wall of secrecy around one of the main controls, like the A330's SS, is a NO-NO. Its a NO-NO, as it is a NO-NO in the Control Center of a Nuclear Power Plant, or as it is in the Control Center of a large cargo ship, or a very large crane operated by a crew, to name a few. In all of those, there are instruments, like in the cockpit, but the controls are not hidden, from the crew present in the control center. As some A/C cockpits do not have this problem, the lack of consistency in the airline industry, may be favored by the lack of regulation in this respect.

The AF 447 accident was caused by the confluence of multiple factors, that span a wide spectrum, which include a few manufacturer problems, which are revealed only in such extreme cases, as the AF447.
While the information made public will be shaped to minimize public perception impact, its likely every organization will do its best to address the problems, even if they are not spelled out straight forward in an official report. As far as the design goes, as I mentioned, new versions/generations will speak by themselves of the problems, and their solution.

Last edited by airtren; 11th Nov 2011 at 13:54.
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Old 11th Nov 2011, 13:41
  #89 (permalink)  
 
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Thanks for the link, Retired F4.

Great. So you recognize that aeroplane was stalled yet keep on drumming on roll behaviour. For Finnegan's sake, can you picture A330 flying at 40 AoA with about 100 KTAS? Ugly, eh? Spoilers are blanketed by wing, rudder is blanketed by fuselage and ailerons don't have much say - going up they're in wings wake, going down makes a bit of difference but very low forward speed makes them not particularly efficient.

What the heck does sidestick have to do with behaviour of aeroplane that is at extreme AoA, beats me. Oh yes - there's a theory that with yoke somehow CM1 would recognize that CM2's control inputs do not have much effect on aeroplane so he would recognize that the aeroplane is stalled and that first and foremost is AoA reduction.

Well, I'm not buying it. He was listening stall warning for 54 seconds and made not a comment about it, let alone done something.

So far, I have found two fuel sources that keep this Hamsterwheel turning

1. People having no grasp of aerodynamics, instrument flying or aeroplane system making elaborate analysis of some technical detail. Not able to take subtle hints their theories are spectacularly flawed, they resort to personal attacks when told so in no uncertain terms.

2. People that have some idea how flying works, take out a detail out of whole picture then trying to reconstruct the whole scene just on that little detail. That their picture bears not much resemblance to original seems not to bother them much.
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Old 11th Nov 2011, 13:52
  #90 (permalink)  
 
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Salute!

@ Zorin

Sorry if I did not my point clear.

- My main point is that even in "direct" law the elevator does not follow the stick inputs as most think. And I am also not sure that "gains" and rates for the ailerons are eliminated.

- I do not feel that the reversion sequence is clearly understood until one goes thru it many times and notes what's protected, what isn't and actually sees/feels the results of control inputs. My personal preference would be to have only one "alternate" law, then "direct" law, and the THS would require manual settings in both.

- The auto-trimming of the THS did not "help". The pilot would have had a harder time holding the AoA and pitch attitude if the THS had stayed where it was when air data went awry. So in that regard I DO THINK the computers got in the way.

Simply stated, I lay most of the fault with the crew but can not rule out contributions by some of the 'bus FBW and display/warning implementations.
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Old 11th Nov 2011, 14:05
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@CONF:

By attempting to force me into the debate on your terms, I think you'll find that it is you who is arguing like a politician. I've already stated numerous times that I don't want to go there again because we've already been there before - you *know* we've been there before, and because I've stated my position that I don't think it's relevant to this case I think it's only fair that is accepted.

Probably going to take a break for a while after this, as it appears the thread is being sucked into the old "interconnected" debate for something like the fifth time, but just to summarise:

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.

Yes, the Airbus sidestick design drops the tactile feedback channel, but whether that is a big deal or not largely depends on your opinion. Some pilots who have grown up flying on feel distrust the design, and they wouldn't be human if they didn't. From an engineering standpoint most of the reason for having interconnection (i.e. the ability to apply extra leverage from the second pilot in the old cable days) was gone by the time controls became fully-hydraulic over 40 years ago. The yokes are cumbersome, and inadvertent bumping or moving of the columns have led to several incidents over the years, some of them fatal. 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. Muddying the issue was the rise in automation during the '70s and '80s and a lot of people got their wires crossed - not helped by the press, who always like a "let's you and him fight" situation.

To my mind, this is irrelevant in this discussion for the reasons I laid out in my third paragraph, and what makes it more so is that 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, and without that it's arguable that even if the PNF had taken control he might not have been able to recover in time.

The reason I say this comes from my sim session, which taught me some things I didn't know - namely that when stalled, the tendency is for the aircraft to respond to aileron input with a roll in the *opposite* direction, and as such it is advisable to use the sidestick for pitch only and to control roll with gentle rudder, which took less than 30 seconds to explain (albeit several attempts for my lead feet to get right ) - but if we are to believe what the BEA is saying then this little bit of life-saving knowledge was something that these professional line pilots had never been told, or at least not recently.

So (sorry for the lengthiness of this rant), 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), they were the ones who ended up with the bad cards and had the accident and in my opinion it is they who should shoulder the lion's share of responsibility for allowing it to happen. I think "blame" is a non-helpful concept in aviation accident investigation and I'm not a fan of the continental practice of making it a judicial matter because it makes getting at the truth problematic (although, truth be told, the Anglo system is much the same but handled by the civil courts).

@gums - I can assure you that once the aircraft stops responding in the manner you expect, the last thought on your mind should be what is protected and what isn't - it's safest to assume that nothing is protected and the utmost caution be taken to get your response right.

Safe journeys folks.
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Old 11th Nov 2011, 14:26
  #92 (permalink)  
 
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Dozy. You're last paragraph re: pilots/Air France. Excellent. It pulls together a major portion of the impetus for disaster we see in this tragedy. I completely agree. Allow me a small addition? With the stage set for LOC in manual under these conditions, (and they were stinko), Airbus shows a remarkable blind spot in monitoring their product whilst in service. This is not a third world fifth owner operator, it is a legacy Flag Carrier.

Wildly expensive and complicated machine systems need nurture. In seeing to it that her operators were allowed singly to abuse her care and operation was a major player in her demise. Her makers lost the marque.

If one truly believes that as automatics increase in capability, Pilotage can degrade, the coffin business will bloom, leastwise whilst airborne.
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Old 11th Nov 2011, 14:55
  #93 (permalink)  
 
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Well, I'm not buying it. He was listening stall warning for 54 seconds and made not a comment about it, let alone done something.
1. People having no grasp of aerodynamics, instrument flying or aeroplane system making elaborate analysis of some technical detail.
And some people have very little grasp of the varied ways in which people gather and process information.

but if we are to believe what the BEA is saying then this little bit of life-saving knowledge was something that these professional line pilots had never been told, or at least not recently.
There have to be a whole lot of jet pilots who have never flown a swept wing jet at very high & at stalled AOA. They have been spending their lives avoiding just that situation.(Non-tactical flying)

A swept wing jet does not behave like a straight wing trainer at high AOA. The dihedral/roll effect from the swept wings is very powerful, particularly at high AOA.
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Old 11th Nov 2011, 15:04
  #94 (permalink)  
 
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Cool

Hi,

The reason I say this comes from my sim session, which taught me some things I didn't know - namely that when stalled, the tendency is for the aircraft to respond to aileron input with a roll in the *opposite* direction, and as such it is advisable to use the sidestick for pitch only and to control roll with gentle rudder, which took less than 30 seconds to explain (albeit several attempts for my lead feet to get right ) - but if we are to believe what the BEA is saying then this little bit of life-saving knowledge was something that these professional line pilots had never been told, or at least not recently.
I don't buy any A330 simulation of stall like you don't buy a cat in a bag
The real thing (full stalling) was never tested on the A330
This was not made cause certainly was taken in account the risk and money
So the choice was to not put in danger the life of a test crew and the risk to loss a frame .. but this imply to put the life at risk of the line crews and the passengers in case of a stall .. as the pilots don't know how the plane will really act at the eventual recovery manoeuvres
Very bad choice
It's really a big issue in the aircraft industry to not perform all the needed tests .. and this not only apply to the planes but also for the parts used
The life boats of the Ocean Ranger (drill rig) where tested many time by nice weather and all was good
When the tragedy was there .. the life boats were pushed by the wind against the columns of the rig .. were crushed even before touch water .. killing all people in
The design of survival gear was not good (location) for bad weather .. but this kind of situation was never tested
Heuristic ?

Last edited by jcjeant; 11th Nov 2011 at 15:15.
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Old 11th Nov 2011, 15:07
  #95 (permalink)  
 
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Originally Posted by DozyWannabe View Post
...
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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Old 11th Nov 2011, 15:17
  #96 (permalink)  
 
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Talking I just settled all the arguments!

Answer Old Carthusian:
Yes by looking at the instruments. An input produces a certain pattern on your instruments and you can understand what your aircraft is doing.
Two points to keep in mind:
-There is no record of what was displayed to the PF, and thus, no proof that he had all the info he needed on his displays. There is no reason to "know" either way if he had working displays. (As we all know, pilots have vigorously resisted the suggestion to install video cameras on the flight deck, just as they resisted the addition of CVR at one time.)
-It hasn't been determined, and probably cannot be, what the poor PF meant when he said, "We have no more indications." Correct me if I'm wrong, but I believe that many here have interpreted that to mean "no speed indications." There's no reason to assume that as gospel.
-Oh, here's a bonus third point! If PF had had a working AoA display, and he had looked at it, ya never know that 228 people might still be walking the earth today.

airtren said:
The AF 447 accident was caused by the confluence of multiple factors, that span a wide spectrum, which include a few manufacturer problems, which are revealed only in such extreme cases, as the AF447.
I'm weighing-in in support of what airtren, Machinbird, and F4 have been trying to say. As a dispassionate observer, their views make the most sense to me, and I have no AB, FBW, or Boeing axe to grind. Suggestions that such contributors are prejudiced or "anti-AB" are simply paranoid, in my view. (See airtren's comment above.) Anyone unwilling to weigh ALL possible factors is not being intellectually honest, yeah you, DW!
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Old 11th Nov 2011, 15:27
  #97 (permalink)  
 
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Clandestino

Let me use some more bandwith then.

Great. So you recognize that aeroplane was stalled yet keep on drumming on roll behaviour.
Read my post. I did not do that.

For Finnegan's sake, can you picture A330 flying at 40 AoA with about 100 KTAS? Ugly, eh? Spoilers are blanketed by wing, rudder is blanketed by fuselage and ailerons don't have much say - going up they're in wings wake, going down makes a bit of difference but very low forward speed makes them not particularly efficient.
Im fully aware how a basic aircraft works or better not works in a stalled condition, they are all similar. ANd i needed no sim time in a A320 like DW to know what ailerons do in a stalled condition.

What the heck does sidestick have to do with behaviour of aeroplane that is at extreme AoA, beats me.
Nothing at all. Could you quote me where i made such an mistake?

Oh yes - there's a theory that with yoke somehow CM1 would recognize that CM2's control inputs do not have much effect on aeroplane so he would recognize that the aeroplane is stalled and that first and foremost is AoA reduction.
Is that your theory? Amazing. I only used it as an example to answer OCs statement, quote below.

Quote:
Confiture
2 PNF knew the PF was making inputs - Did they know which inputs he was making ?

Answer Old Carthusian
Yes by looking at the instruments. An input produces a certain pattern on your instruments and you can understand what your aircraft is doing.

Retired F4
Would you explain yourself in relation to the timeframe starting from 02:12:45?
Not more and not less. By the way, i still wait on the answer to my question, how the PF or the captain could have seen on the instruments, that despite the continuous right bank PF had full left SS.

Or is this answer no longer relevant as it does not fit in the "everything is right, nothing needs to be changed" scheme?


Well, I'm not buying it. He was listening stall warning for 54 seconds and made not a comment about it, let alone done something.
The simple answer is he should have failed his medical previously due to a hearing problem, or he wanted to kill himself, or....
what is your answer?

So far, I have found two fuel sources that keep this Hamsterwheel turning

1. People having no grasp of aerodynamics, instrument flying or aeroplane system making elaborate analysis of some technical detail. Not able to take subtle hints their theories are spectacularly flawed, they resort to personal attacks when told so in no uncertain terms.

2. People that have some idea how flying works, take out a detail out of whole picture then trying to reconstruct the whole scene just on that little detail. That their picture bears not much resemblance to original seems not to bother them much.
Now where do i fit in?

I like the term KISS, but not in the cause of accidents. I like to turn every stone and look under it, and most of the people you acuse to turn the hamster wheel do the same. Its collecting bit for bit, some turn out to be one way streets, some need further consideration.

I take out a detail and discuss it, but the reconstruction will need lots of those details to get the picture complete. To cry out loud when one of those details is discussed that this is against A or that the whole accident is hung on one single nail is tiring.

I for myself leave it anyway to BEA and Airbus and whatever agency is responsible to make the final saying. But that does not keep me from telling my oppinion on certain aspects of this accident.

But if you do not like this "hamster wheel" then it would be very simple to just stop reading it.

Last edited by RetiredF4; 11th Nov 2011 at 16:00.
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Old 11th Nov 2011, 15:39
  #98 (permalink)  
 
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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.
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Old 11th Nov 2011, 15:45
  #99 (permalink)  
 
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My main point is that even in "direct" law the elevator does not follow the stick inputs as most think.
Problem one: those "most" include the ones who designed Airbus, the ones who certified and the ones who fly it. Direct law in pitch is proportional stick-to-elevator displacement.

Problem two: AF447 went into ALT2 so it wasn't in direct pitch. To oversimplify: ALT2 in pitch is basically G demand. That the aeroplane remained in ALT2 is indication inertial reference was working.

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. Good news is: those who really can have extremely good chances of getting to grips with Airbus.

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
Opinion of certifying authorities is that it matters not.

Originally Posted by DozzyWannabe
when stalled, the tendency is for the aircraft to respond to aileron input with a roll in the *opposite* direction, and as such it is advisable to use the sidestick for pitch only and to control roll with gentle rudder
Correct for almost any aeroplane. Caveat is that it works as long as there is enough rhoveesquared and controls are not blanketed. No transport aeroplane has ever been put intentionally far beyond stall AoA therefore while sim behaviour is extremely realistic just above stall AoA, it turns into guesswork as AoA is increased, which is not a problem at all. Sims, just like aeoplanes, re not meant to be operated outside the envelope.

Originally Posted by DozyWannabe
but if we are to believe what the BEA is saying then this little bit of life-saving knowledge was something that these professional line pilots had never been told, or at least not recently.
Say what?!? Professional line pilots are trained to avoid stall, roll control via rudder while stalled is domain of flight testers and those bent on serious aerobatics! Life saver would be push forward!
Originally Posted by DozyWannabe
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
So? There are thirty-seven cases of unreliable airspeeds on 330/340 aeroplanes listed in interim2. Companies are de-identified, however, given registration and date, it is easy to find out who was the operator at the time of the incident. On a few occasions it was AF crews, that despite having no training at manual handling, actually lived through the experience. This might lead the AF into believing that all of their crews would cope with the problem under any circumstances.

Of course, it would be mistake to interpret this as "It was deceased pilot's fault". There definitively were organizational precursors but pilots were not lambs lead to slaughter by tricky aeroplane and inadequate training.

Originally Posted by Machinbird
And some people have very little grasp of the varied ways in which people gather and process information.
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...

Originally Posted by Retired F4
By the way, i still wait on the answer to my question, how the PF or the captain could have seen on the instruments, that despite the continuous right bank PF had full left SS.
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?
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Old 11th Nov 2011, 17:14
  #100 (permalink)  
 
Join Date: Jan 2005
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Originally Posted by DozyWannabe
By attempting to force me into the debate on your terms, I think you'll find that it is you who is arguing like a politician. I've already stated numerous times that I don't want to go there again because we've already been there before - you *know* we've been there before, and because I've stated my position that I don't think it's relevant to this case I think it's only fair that is accepted.
Relevant or not is not my question.
I don't force you to anything - If you have nothing to argument you don't have to write that long either.

At least I'm not the only one to perceive what I would qualify also as intellectual dishonesty.
Originally Posted by Organfreak
I'm weighing-in in support of what airtren, Machinbird, and F4 have been trying to say. As a dispassionate observer, their views make the most sense to me, and I have no AB, FBW, or Boeing axe to grind. Suggestions that such contributors are prejudiced or "anti-AB" are simply paranoid, in my view. (See airtren's comment above.) Anyone unwilling to weigh ALL possible factors is not being intellectually honest, yeah you, DW!
Originally Posted by DW
Probably going to take a break for a while after this
I also think you need one.
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