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AF 447 Thread No. 5

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AF 447 Thread No. 5

Old 5th Aug 2011, 21:24
  #1641 (permalink)  
 
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Xcitation

Yes and no.

Not easy, not by any means, but troubling that they did not appear to diagnose the stall to the very end (unless you interpret the CDB's "impossible" remark). There were plenty of hurdles, e.g. the 60kt alarm "cut off" and no AoA indication (and the PF and PNF were probably receiving very different information at times), but also plenty of clues - pitch/attitude, trim (THS position), buffet and the VSI plummeting downwards. And the audible stall alarm, intermittently.

What worries me more is whether, unless the stall had been prevented in the period after A/P disconnect and reversion to ALT law, this crew were trained to recover from such a stall by hand flying and even with FLT380 to play with? As I have said previously, I believe PNF was close to diagnosis. From what has so far been disclosed, I still wouldn't bet my mortgage (if I still had one) on their recovering and that poses a lot of questions for the industry.....

Re: QF72. I just blame the US Navy! I remember flying near "Harold Holt" on the run down from Kuala Lumpur to Perth in the early-80s and strange things happening to my avionics (that was a 747, not an AB).......

Last edited by Welsh Wingman; 5th Aug 2011 at 21:46.
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Old 5th Aug 2011, 21:29
  #1642 (permalink)  
 
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Page 45 again

For me the previous two graphs (thanks for your comments) were just 'stepping stones' to the graph I was working on: AF447 cL-alpha prior to and post-stall.
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Old 5th Aug 2011, 21:32
  #1643 (permalink)  
 
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Attitude

Something like this stuck to a flat surface would tell you if the plane was pointing up/down and whether the wings were level or not:

Caravan, Motorhome Universal Triangular levelling device Spirit Level.: Amazon.co.uk: DIY & Tools Caravan, Motorhome Universal Triangular levelling device Spirit Level.: Amazon.co.uk: DIY & Tools


There are bigger/more expensive versions too, with digital readouts and 0.1degree accuracy. No computer needed. How about 2 of these:

Digital Angle Gauge / Protractor / Inclinometer / Bevel Box WITH LEVEL BUBBLE & HOLD BUTTON + Leather Pouch & Batteries: Amazon.co.uk: DIY & Tools Digital Angle Gauge / Protractor / Inclinometer / Bevel Box WITH LEVEL BUBBLE & HOLD BUTTON + Leather Pouch & Batteries: Amazon.co.uk: DIY & Tools
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Old 5th Aug 2011, 21:39
  #1644 (permalink)  
 
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Originally Posted by Black Sheds View Post
The automatic systems and glass cockpit completely failed the pilots by providing erroneous and variable indications.
Really? As far as I can see, only the instruments related to pitot data could be considered unreliable, that is until the point that the AoA became so extreme that various anomalies that would have messed up any display reliant on air data, mechanical or digital.


With a carefully designed back-up of dependable instruments such as gyros and inertial navigators, and others, pilots would not be without believable data.
Where do you think the data in a glass cockpit comes from? The glass cockpit instruments are *driven* by gyros and inertial sensors, and they were telling the truth the whole way down.
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Old 5th Aug 2011, 21:41
  #1645 (permalink)  
 
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From post #1625:

Bus pilots have stated that ALT LAW behaves like no other a/c you have flown!
To set the record straight, some "Bus pilots" have not made this statement.
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Old 5th Aug 2011, 21:42
  #1646 (permalink)  
 
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How is it possible?

It seems to me that the PNF was giving instructions to the PF based on indications he had, and PF didn't.
It also seems to me that the PF had his own indications, but was not trusting them, they were too crazy, confusing.
It also seems to me that the Captain was puzzled by what was going on with both side indications.

On the PF's side one thing (or nothing sometimes), on the PNF maybe just the altimeter worked kinda properly.

So it makes sense to me that the PNF did not have all the information necessary to hold the plane (i.e. Attitude Indicator), so he kept telling PF what to do.
On the other hand, PF had other kind of information, which PNF didn't.

Imagine the Captain's situation, he can't believe in his eyes. What he is seeing is not possible.

What is he seeing?
We don't know, many parts of the CVR are missing (to us).

I am not suggesting that a "coverup" is going on, but lets suppose BEA has an "inclination" to suggest that the pilots could have saved the situation. If the conversation between the 3 pilots would show they were confused, why show just part of the conversation?
Why show only the "confused" part?

All three pilots didn't have the slightest idea of what was going on, and is very hard to believe they only lost airspeed and AP.

Maybe when we see the full CVR trancript...
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Old 5th Aug 2011, 21:49
  #1647 (permalink)  
 
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All the talk of what is a stall etc. and how us pilots 'know' exactly what it is like to be in a stall....What we don't know is if we would be able to decide if we were in a stall or a dive should we be in a cockpit with no outside visibility or working instruments and all we knew was that we were descending at a rate where we could be almost in zero g.
That may well be the difference between our experiences of stalling and their experiences on the day - experiences that no simulator training would have been able to reproduce.
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Old 5th Aug 2011, 22:06
  #1648 (permalink)  
 
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Originally Posted by vanHorck
The French language is in my humble opinion too ambivalent to be used in a factual environment like a cockpit in distress.
Well sure. Only native anglophones /[insert your own culture], preferably those raised near [insert your place], should be recruited to fly modern jets. Many languages and cultures are unable to provide the mandatory level of efficiency required. People tends to say words that, once translated into English /[ or whatever], doesn't make enough sense to me. Consequently, such talks should be banned from cockpits and considered unsuited for high-technological environements due to their intrinsic flaw at being fully understandable by me.

Such statement do not surprise me. I could say exactly the same about English/[insert your own langage] forms but I'm not so ethnocentric.

What cause such a distorsion about the exact meaning of those words is primary due to several factors [many that a non native, whatever his proficiency level, would never catch in a lifetime]:
1. We are not listening at what they said, it is not complete and we are reading it from a poorly made transcription. Add the fact that, for the majority of the readers here, you are reading it from a poorly made translation of this poorly made transcription.

2. French talk is quite different from French written forms. Without its prosodie - rythm, tone, emphasis, etc. - it may be clearly ambiguous from the direct transcription. Hence, without listening the original conversation in integrality, I'm a bit clueless about their talks referential. Some of the referential is also lost by not seeing them, because there is many "shortcuts" used for talking. In fact, the ammount of informations they had, when talking to each others, is not part of this transcription. I'm sure that accessing to the original record would clear many ambiguities.

3. I suppose that BEA, at this stage, released the minimal work on CVR voluntarily; only people which had heard the CVR would have a right idea of what happened in the cockpit. There was strictly no effort made to make it really meaningful in English version -it is called a litteral translation: emphasis is put on words, without bothering about sense.

4. Last but not least, making sense is not a question of langage, it is a question of discipline. What I'm able to infer from the first reading is a serious lack of crew discipline. No further comment is needed about it.
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Old 5th Aug 2011, 22:21
  #1649 (permalink)  
 
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Takara, do you mean that flight deck crew indisipline was a factor in your interpretation of what you have read (in your native tounge I would hope?) It would not have been the first accident that ever happened with such an enviroment (the Korean 747 crash at Stansted springs to mind), and it wouldn't be the last..

Last edited by Alber Ratman; 5th Aug 2011 at 23:23.
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Old 5th Aug 2011, 22:25
  #1650 (permalink)  
 
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I have to put my ten cents worth in here. Takata is right IMHO, about French. The same applies to all languages that I have encountered, including English. No way can anyone, who has not heard the CVR, can arrive at an accurate interpretation of what was said. Also people gesture with their hands, arms ,face and head, when talking. The "Continentals" being the greater users of their bodies when communicating.
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Old 5th Aug 2011, 22:26
  #1651 (permalink)  
 
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takata,
That's what I tried to say, but a lot less clearly....
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Old 5th Aug 2011, 22:28
  #1652 (permalink)  
 
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TurboTed . . . Spirit Levels

Good thought, but unfortunately these are also driven by "G" forces. They are not accurate in a turn, during acceleration, etc.
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Old 5th Aug 2011, 22:42
  #1653 (permalink)  
 
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vanHorck / Takata

Other forums can deal with the Seven Years War of 1756-63 and the rise and hegemony of the English language (even as spoken by our American cousins "over the pond") as the "global" language(!), so let's focus on Takata's "discipline" good point (well made). AF had 3 hull losses in 9 years, each where there have been not insubstantial CRM issues to varying degrees. But I cannot see where the use of the French tongue per se (as opposed to the over colloquial use of any language) has ever been a contributing factor to the hull loss (as opposed to a nuisance to non-French speakers in air accident reports!). If either the PF or PNF on AF447 had diagnosed the problem, it would have been conveyed to the other and to the CDB. There is nothing in the CVR so far disclosed, any more than anything in their respective flying history and experience, to suggest other than F/O 37 should have been PIC in CDB's absence (as PNF in LHS). I am really struggling to get "my head around" the entire "relief" pilot regime that was in force. I can see the benefit of a CPT having the discretion to select a PIC, e.g. a longserving F/O unsuitable to ever become a CPT or a less experienced but still experienced "high flyer" of a F/O heading upwards, but I can see nothing to indicate why F/O 32 should not have been under F/O 37. The latter should not have been "nagging", as one post (I think accurately) described his instructions to the PF.

Last edited by Welsh Wingman; 5th Aug 2011 at 23:10.
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Old 5th Aug 2011, 23:04
  #1654 (permalink)  
 
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Originally Posted by Alber Ratman
do you mean that flight deck crew indisipline was a factor in your interpretation of what you have read (in your native tounge I would hope?) It wouldn't have been the first accident that ever happened with such an enviroment (the Korean 747 crash at Stansted springs to mind), and it would be the last..
After my first reading (yes, it's my mother tongue), I was quite astonished that a supposed "professional" crew would behave like that in such a critical situation. Good professionnals may use sometime a "relaxed" way of communication, but if the situation would become critical, they should instinctively revert to their discipline of communication.

I'm also quite sure that the CVR transcript was expurgated from many slang forms which should have been added to several sentences heard. PF sounds like a teenager, not a 32 years old fully qualified A330 driver. Captain said almost nothing, or it was cut in report.

BEA also inserted numerous leads (flight related) that, once put together, are showing a very same pattern all along this flight. Going further into this chapter, at this point, would not help the BEA as full cooperation with the company is needed in order to conduct this investigation to its end.
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Old 5th Aug 2011, 23:06
  #1655 (permalink)  
 
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@CONF iture:

Hi Conf,

This discrete represents the source of the vertical speed indication on PFD.

From the report: page 94 (English version)

@12:11:45
---
The vertical speed is no longer calculated by the IR (Inertial reference)
but by the ADR.
It is about -10,000 ft/min.

and confirmed by FCOM.

FCOM
1.31.40

INDICATIONS ON PFD

VERTICAL SPEED:

The displayed vertical speed information is normally based on both inertial and barometric data.
If inertial data is not available, it is automatically replaced by barometric information.
In this case, the window around the numerical value becomes amber.
That will raise another question, why was IR V/S not available?
was it related to:
02:13:14 - .1/FLR/FR0906010211 34123406IR2 1,EFCS1X,IR1,IR3,,,,ADIRU2 (1FP2),HARD
and this fault message related to disapperance of FPV?

The presence of the “FLAG FPV ON PFD CAPT (F/O)” message indicates that TRK-FPA
(Flight Mode Annunciator) mode was selected by the crew during minute 2 h 11, but that the
FPV was unavailable (see interim report 2 for details on the conditions of availability). Based
on a study of the other relevant parameters it may be concluded that the FPV was selected between
2 h 11 min 48 and 2 h 11 min 54.




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Old 5th Aug 2011, 23:10
  #1656 (permalink)  
 
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Cool fluid level meters

Hi,

TurboTed
Something like this stuck to a flat surface would tell you if the plane was pointing up/down and whether the wings were level or not:
Think again
At 2min10

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Old 5th Aug 2011, 23:25
  #1657 (permalink)  
 
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"c'est pas possible"

2 h 12 min 44:
CDB: (…) C’est pas possible

There has been some discussion concerning what the captain was referring to when he said this. As a further note on language (this is becoming quite a theme, here), please note that "c'est pas possible" could also quite easily be a generalized expression of frustration. For example, if you arrive at the movie theater only to be told that the movie is sold out, you may well exclaim "c'est pas possible!" It doesn't mean you think that it's actually impossible that the movie is sold out, or that you don't understand how it came to be sold out.

I'm not saying this is the case here. Without hearing how the words were said, it's impossible to conclude anything either way. I just wanted to raise this as a possible option before people get too far into speculating which instrument he might have been looking at.
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Old 5th Aug 2011, 23:30
  #1658 (permalink)  
 
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Originally Posted by A33Zab
That will raise another question, why was IR V/S not available?
was it related to:
02:13:14 - .1/FLR/FR0906010211 34123406IR2 1,EFCS1X,IR1,IR3,,,,ADIRU2 (1FP2),HARD
and this fault message related to disapperance of FPV?
FPV ECAMs fault are due to their selection and rejection (they were unselected before this point) because airspeed was < 60 kt.

It looks like CONF-iture doesn't read (or believe in) BEA reports; this fault was explained and very understandable considering that pressure altitude, barometric vertical speed and true airspeed were altogether affected by high alpha and unvalid dynamic pressure resulting. In fact, it was a triple IR rejection of ADRs - this fault was reported three times, one by each IR, but consolidated into one single ACARS:

Page 38, report #2.

ADIRU2 (1FP2) (2 h 11)
ATA: 341234
Source: IR2
Identifiers: *EFCS1, IR1, IR3
Class 1, HARD

This message was generated by IR 2. For an ADIRU of this standard, it means that the IR considered that the three ADRs were invalid, that is to say that at least one of the three parameters was invalid (SSM status not NO) amongst pressure altitude, barometric vertical speed and true airspeed. As soon as the third ADR is rejected, the IR generates a message pointing to its ADIRU. If one of the IRs considers the three ADRs as being invalid, this must also be the case for the other IRs. It is therefore logical that, in parallel with this ADIRU 2 message generated by IR 2, an ADIRU 1 message was generated by IR 1 and an ADIRU 3 message by IR 3, which would explain the presence of the latter amongst the identifiers.

The fact that EFCS1 was present amongst the identifiers preceded by an asterisk indicates that EFCS1 had at least generated one class 2 message, perhaps followed by a class 1 message. There are too few elements available to determine precisely what the presence of EFCS1 amongst the identifiers means. Nevertheless, it is possible to state that it concerns a rejection of ADR by at least two PRIMs. It has not been possible at this stage to understand why EFCS2, the clone of EFCS1, is not an identifier.
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Old 5th Aug 2011, 23:35
  #1659 (permalink)  
 
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Spagiola

It's just the most tantalising limited-release CVR comment, at FLT200. The reality is that the BEA, even with access to the full FDR/CVR, may never know what the CDB meant by that remark (and the possibilities are endless to speculate over).
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Old 5th Aug 2011, 23:52
  #1660 (permalink)  
 
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Originally Posted by Welsh Wingman
It's just the most tantalising limited-release CVR comment, at FLT200. The reality is that the BEA, even with access to the full FDR/CVR, may never know what the CDB meant by that remark (and the possibilities are endless to speculate over).
As the exact quote is:
CDB: (…) C’est pas possible
One knowing what was "(...)", added to his tone, would have a very good idea of what the captain really expressed. But, I'll refrain from proposing to change this expression into something meaningful... as some could complain to JT about my langage.
Just note that Spagiola remark is by far the best proposal with all clues on hands.
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