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AF 447 Thread No. 10

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AF 447 Thread No. 10

Old 22nd Sep 2012, 21:16
  #481 (permalink)  
PJ2
 
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You're welcome TTex - yeah, I recall the 320 was quite different than the 330/340.

Like gums says, tiny movements on the stick are all that are needed.
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Old 22nd Sep 2012, 23:03
  #482 (permalink)  
 
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Let me rephrase, incorporate this:

"PJ2 Like gums says, tiny movements on the stick are all that are needed."


and ask, Would a degrade to DIRECT LAW have been more in tune with what we know of Airbus FBW?

As In:

Tiny movements on the stick are not available Only tiny trim originated inputs....

Last edited by Lyman; 22nd Sep 2012 at 23:05.
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Old 22nd Sep 2012, 23:32
  #483 (permalink)  
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Sorry Lyman I don't understand your question or point about "being in tune with what we know of Airbus fbw", or your observation, "Tiny movements on the stick are not available Only tiny trim originated inputs....".
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Old 22nd Sep 2012, 23:41
  #484 (permalink)  
 
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I think Airbus philosophy in general is excellent, but only ask that in the condition of 447, where complete authority in Pitch is retained, that here, specifically, a Default to Direct Law would involve caging the Pitch within strict limits eg: available, but in small doses.

Bonin must be the only pilot who would have acted this way? It depends on what one would expect from the pilot population as a whole, whether the risk to the aircraft with poorly trained airmen would warrant a scheme that went to Direct Law when the Airspeeds were lost. imo.
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Old 23rd Sep 2012, 01:55
  #485 (permalink)  
 
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Originally Posted by Lyman
It depends on what one would expect from the pilot population as a whole, whether the risk to the aircraft with poorly trained airmen would warrant a scheme that went to Direct Law when the Airspeeds were lost.
Whether you like it or not, the aircraft reverted to ALT2b.

Consider the pilot knows what's best and demands NU on SS, hence the Elevators follow and as the airspeed is bled off and the 'g' commanded is not being met, the THS commences its journey. It knows no better, only that the pilot knows best.

The point of all this is that if the aircraft during this UAS event had actually gone into Direct Law, and the THS was limited at 3° NU, the aircraft when handled the way it was would still have stalled. Owain Glyndwr has pointed out many times that the Elevators [alone] were quite capable of providing whatever NU/ND was requested.

Since when has an airframer been responsible for the actions of poorly trained airmen/women? I'm not talking about the 'deep pockets' litigation that seeks to make them responsible, but rather the expectation that the aircraft will be flown by properly trained and competent personnel.

You can argue until the 'cows come home' [in your grassy valley], but in the case of AF447 the expected procedures were not followed, CRM was lousy, and if there was any acknowledgement of the situation they were in, it must have been done with 'sign language'.

AB will most likely make changes to the way problems with faulty air-data is revealed to the crew, but this is to be expected in line with progressive improvements to the software. Now this could also be construed as further 'dumbing down' of the competency levels required to fly their aircraft. If its in the interest of 'safety', then I believe most will manage to live with it.

Now where is the concierge?

Last edited by mm43; 23rd Sep 2012 at 01:56.
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Old 23rd Sep 2012, 02:43
  #486 (permalink)  
 
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Originally Posted by BOAC
but the one big problem we have is the total illogicality of the response of PF in pitch and the apparent lack of 'command' (CRM if you will) from PNF.
Illogical in its excessive amplitude and in its duration yes, but certainly not illogical in itself, what do you do suddenly 400 feet below your cruising FL and your aircraft pitching 2 or 3 degrees under a normal cruising attitude ?

Mention the 'O' bird as you wish, but the initial response of PF in pitch was not fatal, it was far to be ideal, but things had stopped to deteriorate before the FD came back and everything started again for the worse.

Much emphasis on the PF case but I find you guys almost too unconcerned by :
  1. The lack of awareness given by the system to the crew
  2. The FD logic
  3. The THS logic
  4. The stall warning logic
  5. The sidestick concept
Those 5 technological elements played against the crew that night.
Change one of those and chances to disrupt the deadly sequence are improved.

I take that opportunity to link a comment by Sullenberger on the sidestick versus …

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Old 23rd Sep 2012, 13:15
  #487 (permalink)  
 
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And where in the final report does it say that "only the pilots" are to blame?

[Hint : it doesn't.]

CONF - Sully says it's his opinion (to which he is welcome) - he doesn't try to present it as fact.

Last edited by DozyWannabe; 23rd Sep 2012 at 13:18.
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Old 23rd Sep 2012, 14:05
  #488 (permalink)  
 
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The only certain fact is that I know is that AF447 crashed into the sea and there killed 228 people
This fact is indisputable (100%) and is recognized by the BEA
Other facts known by the BEA are not a 100% certainty and therefore logically BEA provides only conclusions based on the opinions (which are welcome) of investigators about those "facts"
Final BEA conclusion after years of investigations:
We don't know why the pilot made climb the plane to finally keep it in a stall position
BEA (as us) also know that the pilot (s) actions give as result 228 people killed
It's certainly not caused by the plane as the BEA state that the plane and systems acted as per design
And as the Airbus A330 design is good (proof is the sooo many hours of flights with no problems .. even in same situations like AF447) .. so the plane can be discarded as culprit ...
Evidently (they can't) the BEA don't blame the crew ... only "conspiracy nuts" think that the BEA blame the crew ...

Last edited by jcjeant; 23rd Sep 2012 at 18:39.
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Old 23rd Sep 2012, 15:56
  #489 (permalink)  
 
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Hi jcjeant,
Evidently (they can't) the BEA don't blame the crew ... only "conspiracy nuts" think that the BEA blame the crew ...
I fully agree. The BEA drew in other agencies and information sources, examined the pertinent evidence, published a factual report listing causes or probable causes and made recommendations to EASA to follow up on. Everyone is entitled to an opinion as to the content of the BEA report, but it become obvious to most when facts turn into fiction such as your statement suggests...
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Old 23rd Sep 2012, 17:44
  #490 (permalink)  
 
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jcjeant wrote:

It's certainly not caused by the plane as the BEA state that the plane and systems acted as per design
And as the Airbus A330 design is good (proof is the sooo many hours of flights with no problems .. even in same situations like AF447) .. so the plane can be discarded as culprit ...
I don't entirely agree, nor does the BEA. Aviation is not for the simple-minded; it's complicated. It depends upon if your view of cause is black-and white or not. A number of recommendations were made for improvements to the aircraft, based on reasonable suspicions (I guess we could call it) as to causation/confusion in the cockpit (flight director behavior, stall warning architecture, etc., etc.: see CONF iture's post). "As per design" may not be good enough, even if said design was approved by the authorities. Learning is on-going, not fixed. There is room in almost any design for improvement. Without, of course, having proof, it is entirely reasonable to speculate that some of the proposed improvements to the A330 might have broken the deadly chain-of-events.

I love Swiss cheese if I'm eating it, but I don't want to ride in it!

Last edited by Jetdriver; 23rd Sep 2012 at 22:25.
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Old 23rd Sep 2012, 19:05
  #491 (permalink)  
 
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cvr, certification

1. I personaly cannot agree the CVR and said it since months. The language is not tbe language used by French professionnal pilots.Not sure that BEA was the redactor . To much sterilized? Not only.
For instance, when you write in (correct) French : "tu montes", we do not know if it means : "tu montes?" ,or "tu montes!"
Listening the text it is not said the same manner and we can understand the correct meaning : the first has "mon" climbing, the second has "mon" climbing and descending.
BEA knows that and would not write a non-pilot used text.
The Captain briefing is really unrealistic.
Did the "human factor" team write that? Not impossible , as the final report describes the sequence in a manner everyday flight would be psychedelic, not only AF447.
Has the CVR been translated to bresilian, then to german, then to english, then to french,with indian or tunisian translators? (In modern decision making they call that "consensus"!)
There is a CVR bug. Do without it.
2 . When you buy a ticket to an airline, you don't buy it to A or B or C. It belongs to certification autority to verify that the aircrafts are safe enough for public transport. Certification autority has to verify that airline pilots' selection and trainning by the airline is adequate for that aircraft, that simulator t eaching is conform to that aircraft. The airline has not the means to verify that, major airline or not. Certification administration is alone to be able to do that and have autority and RESPONSABILITY to do that job. It is THEIR JOB.
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Old 23rd Sep 2012, 20:12
  #492 (permalink)  
 
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Certification administration is alone to be able to do that and have autority and RESPONSABILITY to do that job. It is THEIR JOB.
That would be the EASA...
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Old 23rd Sep 2012, 23:37
  #493 (permalink)  
 
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In the 1950s and 1960s there were far more aircraft accidents as a proportion of the world transport fleets. Many then seemed to have a number of causes or contributing factors, often three or more. Many of these contributing factors have been "designed out". Systems have become more reliable, enabling very high and profitable utilisations.

" Simple things", like Checklists and Weather Minima, better landing aids, Flight Time limitations, Aquaplaning, Aircraft Performance calculation graphs were some of the items which only ultimately were to reach my level of knowledge as a First Officer. Some of this may have been known elsewhere in a Company, but prior to photocopying, much would have been kept in a Head Office drawer !

Flying training required, then, for a F/O was 6 T/Os and Landings, by day.
A Captain only had to do 5, some at night and with an engine failure.
( With this level of training......... !)

(If I exceeded 125 hours flying in a month, I would require a further medical ("to see if I was fit for a further 125 hours," it was said. !))
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Old 24th Sep 2012, 12:56
  #494 (permalink)  
 
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Originally Posted by studi
The main lesson besides all the detailed system aspects is that also an Airbus pilot should view his Airbus like any other conventional plane and fly it like one.

Pitch and Power determine your trajectory, and your job is to control this trajectory. This is done by setting appropriate pitch and power regularly manually.
I'll agree with pitch and power and regular practice. Can't agree about the fly it like a conventional airplane, especially when things are abnormal. Auto trim for "g" and flight path make the airbus unlike a conventional aircraft.
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Old 24th Sep 2012, 13:48
  #495 (permalink)  
 
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Mixing and matching points
mm
AB will most likely make changes to the way problems with faulty air-data is revealed to the crew, but this is to be expected in line with progressive improvements to the software.
Now this could also be construed as further 'dumbing down' of the competency levels required to fly their aircraft.
If its in the interest of 'safety', then I believe most will manage to live with it.
Consider the pilot knows what's best and demands NU on SS, hence the Elevators follow and as the airspeed is bled off and the 'g' commanded is not being met, the THS commences its journey. It knows no better, only that the pilot knows best.
That is a sound basic design philosophy.
I note a few points from CONFiture that what the pilot "knows" when he is in "knows best" mode depends upon two things:
how in depth his aircraft systems knowledge is,
and what info he has available to establish his event particular knowledge.

They go hand in hand.

Another point made was that to get to
"I need to use the UAS procedures"
certain key bits of knowledge are needed. This folds into mm43's point.

While one is sorting that out, it would seem to me that basic airmanship includes a scan that would alert you to the fact that one is changing state.
"Heh, while I'm getting this squirrely little roll problem sorted out and regaining a few hundred feet, I need to get back to my desired/assigned altitude."
The above is a standard, novice level instrument flying problem. What AF447's crew had as an added twist was that airspeed as a cross check performance indication was missing. Since the AH/attitude indicator was working (as best as we can tell, supported by PF initially relying on AH/attitude indicator to get a grip on his roll excursions, eh?) ... that should not be too big of a problem.

Basic pilot skills tell you that if you have not yet changed power, nor configuration, your speed and altitude are trade offs for one another. Set an attitude, see what changes, adjust, see what changes, adjust, and so on. You are back to straight and level soon enough.

Basics.

Even though the pilot of the day has lost his speeds, he could know that with no power change, increase of altitude was going to slow him down. (and vice versa). Once the power changed as the problem proceeded, the above isn't the simple adjustment problem, but change in altitude still ought to be telling the flying pilot something about his flying performance.

I get the impression that flying the bird/FPV seems to have replaced a basic instrument scan. Maybe just in this case.

One cannot lay the blame for something like that at the foot of Airbus, or of Boeing, or any single design bureau. Such aids to instrument flying have been in the aviation business for decades, and very handy they are! They are an aid to an already developed skill, the instrument scan, and do indeed reduce cockpit workload.

This takes me back to: how often does the average pilot actually fly / practice his instrument scan with fewer features enabled?

For a given pilot, how long will it take to get you to restart your instrument scan when the standard (and generally reliable) features take some time off?
How prepared are you?
How often do you get to practice? <-- Does airline management understand why that last question is so important?

Last edited by Lonewolf_50; 24th Sep 2012 at 13:57.
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Old 24th Sep 2012, 14:10
  #496 (permalink)  
 
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Some infos (real world)
G1 - Justiça do RN condena Air France a indenizar família de vítima do voo 447 - notícias em Rio Grande do Norte
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Old 24th Sep 2012, 16:24
  #497 (permalink)  
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Lonewolf 50;
Basic pilot skills tell you that if you have not yet changed power, nor configuration, your speed and altitude are trade offs for one another. Set an attitude, see what changes, adjust, see what changes, adjust, and so on. You are back to straight and level soon enough.
Yes - and this is what the FCTM on Unreliable Airspeed describes; small adjustments, wait...etc
I get the impression that flying the bird/FPV seems to have replaced a basic instrument scan.
Possibly. Not all transport pilots are familiar with the indication and so it requires training to use effectively and safely. It's a trajectory indicator as we know, (which is why it is removed upon selecting TOGA on a G/A) and while useful in some circumstances it has to be used in conjunction with energy awareness and not used alone to fly the aircraft. I still find it difficult to accept that pilots at this level would follow the flight directors and compromise the energy level of the aircraft but I think a valid point has been made during these discussions.

On your last comment, no, I don't think airline managements comprehend the value of raw data/manual flying practise. I think management awareness atrophies as financial constraints and complex simulator scripts combine over time to push out "that which pilots ought to know already", to concentrate on the competent management of autoflight systems in normal and abnormal flight circumstances.

In my experience, mere "practise" was sometimes given by individual instructors who knew its value but only when the script had been finished. Box-ticking has its value if the boxes are appropriate to training requirements and ensuring standards are met but manual flight and raw-data approaches are usually left out of the session. I think the need has been amply demonstrated and hopefully a refocus on the basics, as you describe them, is occurring. I've been away from it now for five years and no longer have a close sense of these sets of priorities.

Last edited by PJ2; 24th Sep 2012 at 16:29.
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Old 24th Sep 2012, 19:38
  #498 (permalink)  
 
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Thank you jcjeant

Tomorrow a french decision about possible no competence of french penal court for ocean pollution in the international waters. The lawyer is Daniel Soulez Lariviere who could ask that for the AF447 case
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Old 25th Sep 2012, 07:16
  #499 (permalink)  

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PJ2

Airline management frankly does not care about how pilots fly, that is what Operations Management headed by the chief pilot is for. Do you really think that the management of an airline discusses how to fly the crates? Not a single second!

The real culprits for these factors are the operations management, therefore pilots with management functions who promised a certain budget and now have to prove it. Or who believe that their flying skills are so good they do not need more training and therefore that is the way for all. In the end it is someone from the pilot community who introduces all this, not 'management'.

I believe not even MOL cares but he vividely repeats what comes from the crownies in the pilot ranks that wanted to be close to him...
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Old 25th Sep 2012, 13:28
  #500 (permalink)  
 
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@Hunter58:

I'm certain that PJ2 is well aware of the distinction, but chose to use a broader definition for the benefit of us laypeople.
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