AF 447 Search to resume (part2)
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Airbus Yesterday Statement
Hi,
As nobody posted it, here is Airbus official statement about those Figaroleaks which are revealing... well, nothing but very old stuff!
It was dated from yesterday: Statements*| Airbus, a leading aircraft manufacturer
_______________________________
Airbus statement regarding media reports about the AF447 investigation
17 May 2011
Some recent media reports about the AF447 accident mention an information note issued by Airbus to its customers. The purpose of this document, known as an AIT (Accident Information Telex), is to provide operators with information related to potential safety recommendations that may derive from an accident investigation.
For this reason, an AIT has to be approved by the authority that manages the investigation; in this case, the BEA (Bureau d’Enquêtes et d’Analyses – French civil aviation safety Investigations and Analysis Bureau). This AIT was approved by the BEA before being issued by Airbus to its customers and does not include any safety recommendation at this stage of the investigation.
Airbus strongly disagrees with any form of speculation in the scope of the safety investigation and regrets any inappropriate communication concerning such a serious event that should always be handled with utmost professionalism.
In cooperation with Air France and the authorities, and since the very first days of the accident, Airbus has been supporting the search for the aircraft as well as the technical investigation to identify all lessons to be learnt in the sole interest of air transport safety.
In this context, Airbus continues to support the BEA which is leading the investigation with expertise.
____________________________
Whatever Airbus is saying, anyway, it certainly won't change Bearfoil/jcjeant (and few others) points because of their own agenda against Airbus and the BEA. From day one, they are charging to shed the descredit over every aspect of this technical investigation, so deep is their hard belief that everything is aimed at "covering up" Airbus/Thales/AF (Whoever French) liabilities.
In this context, "Airbus continues to support the BEA which is leading the investigation with expertise" should sound at their ears like: "Airbus is very confident that it will be fully cleared by its BEA old friends".
And so on...
Those speculations based on previous speculations will certainly be confirmed by future speculations based on the previous ones and might end, at some point, by sounding enough like some "truth" if it is repeated ad nauseam.
That's their goal.
As nobody posted it, here is Airbus official statement about those Figaroleaks which are revealing... well, nothing but very old stuff!
It was dated from yesterday: Statements*| Airbus, a leading aircraft manufacturer
_______________________________
Airbus statement regarding media reports about the AF447 investigation
17 May 2011
Some recent media reports about the AF447 accident mention an information note issued by Airbus to its customers. The purpose of this document, known as an AIT (Accident Information Telex), is to provide operators with information related to potential safety recommendations that may derive from an accident investigation.
For this reason, an AIT has to be approved by the authority that manages the investigation; in this case, the BEA (Bureau d’Enquêtes et d’Analyses – French civil aviation safety Investigations and Analysis Bureau). This AIT was approved by the BEA before being issued by Airbus to its customers and does not include any safety recommendation at this stage of the investigation.
Airbus strongly disagrees with any form of speculation in the scope of the safety investigation and regrets any inappropriate communication concerning such a serious event that should always be handled with utmost professionalism.
In cooperation with Air France and the authorities, and since the very first days of the accident, Airbus has been supporting the search for the aircraft as well as the technical investigation to identify all lessons to be learnt in the sole interest of air transport safety.
In this context, Airbus continues to support the BEA which is leading the investigation with expertise.
____________________________
Whatever Airbus is saying, anyway, it certainly won't change Bearfoil/jcjeant (and few others) points because of their own agenda against Airbus and the BEA. From day one, they are charging to shed the descredit over every aspect of this technical investigation, so deep is their hard belief that everything is aimed at "covering up" Airbus/Thales/AF (Whoever French) liabilities.
In this context, "Airbus continues to support the BEA which is leading the investigation with expertise" should sound at their ears like: "Airbus is very confident that it will be fully cleared by its BEA old friends".
And so on...
Those speculations based on previous speculations will certainly be confirmed by future speculations based on the previous ones and might end, at some point, by sounding enough like some "truth" if it is repeated ad nauseam.
That's their goal.
Last edited by takata; 18th May 2011 at 12:16.
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@TurbineD thanks for the link to http://www.smartcockpit.com/data/pdf...For_Pilots.pdf
there is a graphic for whigt and balance (CG limits) on s.10
the range for an A330-200 with 210t is from 17 to 39%
there is no advice that the stability is badly different in this range...
and no advise what is the most stable position of CG (24...26% ???)
• No crew action is required for normal operation except initiation and termination ( s101)
and s.101ff........
• Abnormal operations :
- forward and (some) inter tank transfers may be initiated manually
so forward transfer of fuel will be possible even without the use of the gravity - Fuel transfer from the trim tank to the inner tanks is performed by the trim tank forward transfer pump through the trim pipe isolation valve (s.97)
again, I am wondering why one can not just switch the system between economical (aft CG) and most save flying (CG=25%) for turbulent weather......
there is a graphic for whigt and balance (CG limits) on s.10
the range for an A330-200 with 210t is from 17 to 39%
there is no advice that the stability is badly different in this range...
and no advise what is the most stable position of CG (24...26% ???)
• No crew action is required for normal operation except initiation and termination ( s101)
and s.101ff........
• Abnormal operations :
- forward and (some) inter tank transfers may be initiated manually
so forward transfer of fuel will be possible even without the use of the gravity - Fuel transfer from the trim tank to the inner tanks is performed by the trim tank forward transfer pump through the trim pipe isolation valve (s.97)
again, I am wondering why one can not just switch the system between economical (aft CG) and most save flying (CG=25%) for turbulent weather......
More info in the SSCVR
Something not identified in the previously posted info relating to the CVR:
This is written rather poorly, what is meant is that the most recent 30 minutes is individually stored, while data from channels 1,2 and 3 are mixed to a single track for 30-120 minutes.
So the recorder is not really a true 4 channel recorder for the 2 hours duration - the area mic is always individually stored, but we really have a hybrid 4/2 channel recorder.
This seems overly complicated and unnecessary given the low cost of solid-state memory. In fact the idea that the 'recorder' is manipulating (mixing and storing) the data once recorded seems astonishing to me... but then I suppose the design is some 20 years old or so (haven't checked that - it is a guess!).
Recording Channels
The recording system consists of four recording channels which simultaneously record audio as follows:
Channels 1, 2 and 3 have a narrow band and allow the recording of signals from the Captain, First Officer and 3rd Occupant via the Audio Management Unit 1RN.
Channel 4 has a wide band and allows recording of the ambient noises picked up by the area microphone and fed via a pre-amplifier to the input transformer for channel 4.
The three narrow band channels are recorded separately during the first 30 min. and are mixed together from 30 min. to 120 min.
The recording system consists of four recording channels which simultaneously record audio as follows:
Channels 1, 2 and 3 have a narrow band and allow the recording of signals from the Captain, First Officer and 3rd Occupant via the Audio Management Unit 1RN.
Channel 4 has a wide band and allows recording of the ambient noises picked up by the area microphone and fed via a pre-amplifier to the input transformer for channel 4.
The three narrow band channels are recorded separately during the first 30 min. and are mixed together from 30 min. to 120 min.
So the recorder is not really a true 4 channel recorder for the 2 hours duration - the area mic is always individually stored, but we really have a hybrid 4/2 channel recorder.
This seems overly complicated and unnecessary given the low cost of solid-state memory. In fact the idea that the 'recorder' is manipulating (mixing and storing) the data once recorded seems astonishing to me... but then I suppose the design is some 20 years old or so (haven't checked that - it is a guess!).
Next of kin
Quote from Golf-Sierra:
As far as checking if there was water in the module prior to powering it up - would not the simplest way be to weigh it?
Nice one. Perhaps the experts can comment?
Garage Years,
Are there no "hot" (pilot-headset) microphone channels?
___________________
Re the subject of alleged leaks: it seems to me that the BEA is on a hiding to nothing here. And so, to a lesser extent, is AI/EADS. Damned if they release anything; damned if they say nothing. And to demand instant publication of raw DFDR data into the public domain would be ludicrous.
What I think we may all agree is that, as the BEA points out, any public speculation about crew performance at this stage – based purely on inference of the AI communiqué to Airbus operators – is unjustified, unnecessary (in the context of current safety), and can only add to the trauma of the next-of-kin.
As far as checking if there was water in the module prior to powering it up - would not the simplest way be to weigh it?
Nice one. Perhaps the experts can comment?
Garage Years,
Are there no "hot" (pilot-headset) microphone channels?
___________________
Re the subject of alleged leaks: it seems to me that the BEA is on a hiding to nothing here. And so, to a lesser extent, is AI/EADS. Damned if they release anything; damned if they say nothing. And to demand instant publication of raw DFDR data into the public domain would be ludicrous.
What I think we may all agree is that, as the BEA points out, any public speculation about crew performance at this stage – based purely on inference of the AI communiqué to Airbus operators – is unjustified, unnecessary (in the context of current safety), and can only add to the trauma of the next-of-kin.
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@GY did you think it can be possible to extrakt a speed info from chanel 4 in case of UAS if you compare the chanel 4 with the sound before an UAS event? (with given altitude...)
Zeedoktor
Complex and rare systems failure vs. inattentive crew cockup.
It may not be "versus" but "combined with" in this case ... if the rumors are founded in fact.
If not, back to the drawing board, but the question remains ... why were they not able to regain control?
They had 30,000+ feet in which to do so, based on FL selected.
What prevented regaining control?
Training?
Simple mechanical failure?
Robot gone made or become counterproductive?
Simple human error?
Man Machine Interface issues?
Complex human error?
The question that has been in my brain since the early going with this mishap is ... why did they (apparently) fly straight into a serious convective weather system? Answering that seems to me to be where ANY aircrew on ANY model passenger jet would be interested learning how easily "this could happen to me / us ... "
That answer is important to pilots, but perhaps not to bean counters and civil damges chasing attorneys.
Complex and rare systems failure vs. inattentive crew cockup.
If not, back to the drawing board, but the question remains ... why were they not able to regain control?
They had 30,000+ feet in which to do so, based on FL selected.
What prevented regaining control?
Training?
Simple mechanical failure?
Robot gone made or become counterproductive?
Simple human error?
Man Machine Interface issues?
Complex human error?
The question that has been in my brain since the early going with this mishap is ... why did they (apparently) fly straight into a serious convective weather system? Answering that seems to me to be where ANY aircrew on ANY model passenger jet would be interested learning how easily "this could happen to me / us ... "
That answer is important to pilots, but perhaps not to bean counters and civil damges chasing attorneys.
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Hi,
The study of some BEA old investigations show clearly some "cover up" .. and in my POV .. this is a discredit for the BEA
Note that "cover up" is not a conspiracy ... it's just hide some informations to the public.
You must also know (or I remind you) who is the owner of the "Le Figaro" :
Dassault.
And Dassault and the constructor of the AF447 A330 have tight financial link.
You can even suppose that the leak come in fact from the BEA .. or Airbus.
They can disapprove after the release of the article (this article was pasted in all the main french newspapers) but this will still in the mind of the general public and that exactly the same behavior you describe .....
It's a way to prepare the public to accept the fact that in their next official BEA report ... crew will be pointed as making errors.
At least it's a possible scenario I can't discard.
In this context, "Airbus continues to support the BEA which is leading the investigation with expertise" should sound at their ears like: "Airbus is very confident that it will be fully cleared by its BEA old friends".
And so on...
Those speculations based on previous speculations will certainly be confirmed by future speculations based on the previous ones and might end, at some point, by sounding enough like some "truth" if it is repeated ad nauseam.
That's their goal.
And so on...
Those speculations based on previous speculations will certainly be confirmed by future speculations based on the previous ones and might end, at some point, by sounding enough like some "truth" if it is repeated ad nauseam.
That's their goal.
Note that "cover up" is not a conspiracy ... it's just hide some informations to the public.
You must also know (or I remind you) who is the owner of the "Le Figaro" :
Dassault.
And Dassault and the constructor of the AF447 A330 have tight financial link.
You can even suppose that the leak come in fact from the BEA .. or Airbus.
They can disapprove after the release of the article (this article was pasted in all the main french newspapers) but this will still in the mind of the general public and that exactly the same behavior you describe .....
and might end, at some point, by sounding enough like some "truth" if it is repeated ad nauseam.
That's their goal.
That's their goal.
At least it's a possible scenario I can't discard.
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pressures in the 6000psi region are common in hydraulic machinery.
The vast majority of hydraulics are pressurised transiently.
Chris:
Not according to the Airbus SDN document I have in front of me.
The crew channels that are recorded are effectively the headset signals, hence only include 'PTT'd' signals, not the live (hot) mic signals from each crew member microphone. The inference in the SDN is that audio not 'transmitted' by either radio or intercom, will be picked up by the area mic.
grity:
Some estimation could be made of speed based on the audio signature, given we have altitude references, and some prior recording segments to act as baselines - you would need this since 250 kts CAS @ FL350, can sound the same as 300 kts CAS @FL200 (numbers made up for demonstrative purposes). However these would likely only be very rough numbers (say in a 30-50 kt range), but if the assumption is that the aircraft lost it's speed data sensors, then this would be one method to provide an estimation of speed.
Are there no "hot" (pilot-headset) microphone channels?
The crew channels that are recorded are effectively the headset signals, hence only include 'PTT'd' signals, not the live (hot) mic signals from each crew member microphone. The inference in the SDN is that audio not 'transmitted' by either radio or intercom, will be picked up by the area mic.
grity:
@GY did you think it can be possible to extrakt a speed info from chanel 4 in case of UAS if you compare the chanel 4 with the sound before an UAS event? (with given altitude...)
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Very true; however the 6000psi is not present 24/7 for 2 years, and it is not present anyway without leaks. Leaks are common (which is why the fluid needs topping up periodically) and are ignored unless significant.
The vast majority of hydraulics are pressurised transiently
The vast majority of hydraulics are pressurised transiently
Hence a good experienced engineer should have no problem designing for a static system.
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Chris Scott,
My reading of the Airbus release posted by Takata is that is says two things: (1) the language of the release was approved in advance by the BEA so don't blame Airbus, and (2), we, Airbus, probably shouldn't have sent it out in the first place. It wasn't needed, and the only thing it produced was premature speculation.
The conundrum of damned if you do, damned if you don't with respect to release of information in the current era is that the 'audience' today is inherently more suspicious and conspiracy-minded than ever. To my knowledge, the BEA has previously not had the experience of the NTSB in doing investigations where conspiracy theories took hold.
In the case of TW 800, aside from a persistent poster on this board who insisted there was a major design flaw in the forward cargo door of the 747, how to address theories propounded by, among others, a former White House press secretary living in Paris?
'Pierre Salinger Syndrome' and the TWA 800 conspiracies - CNN
Or of an academic of some repute well-connected in some government circles (appointed by George W. Bush to a government agency) that terrorists brought down AA587?
Why Did American Airlines 587 Crash? :: Daniel Pipes
I've come to believe that its better to provide preliminary information as soon as practical, --before alternative explanations fantasized by the conspiratorialists really take root in the public psyche.
My reading of the Airbus release posted by Takata is that is says two things: (1) the language of the release was approved in advance by the BEA so don't blame Airbus, and (2), we, Airbus, probably shouldn't have sent it out in the first place. It wasn't needed, and the only thing it produced was premature speculation.
The conundrum of damned if you do, damned if you don't with respect to release of information in the current era is that the 'audience' today is inherently more suspicious and conspiracy-minded than ever. To my knowledge, the BEA has previously not had the experience of the NTSB in doing investigations where conspiracy theories took hold.
In the case of TW 800, aside from a persistent poster on this board who insisted there was a major design flaw in the forward cargo door of the 747, how to address theories propounded by, among others, a former White House press secretary living in Paris?
'Pierre Salinger Syndrome' and the TWA 800 conspiracies - CNN
Or of an academic of some repute well-connected in some government circles (appointed by George W. Bush to a government agency) that terrorists brought down AA587?
Why Did American Airlines 587 Crash? :: Daniel Pipes
I've come to believe that its better to provide preliminary information as soon as practical, --before alternative explanations fantasized by the conspiratorialists really take root in the public psyche.
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"(2), we, Airbus, probably shouldn't have sent it out in the first place. It wasn't needed"
To the best of my recollection, Airbus has always issued updates on major accidents when there is any development, such as the downloading of the DFDR. Clearly the info downloaded hasn't raised any flags, and this would normally need to be communicated. All airline safety departments would require this information immediately.
To the best of my recollection, Airbus has always issued updates on major accidents when there is any development, such as the downloading of the DFDR. Clearly the info downloaded hasn't raised any flags, and this would normally need to be communicated. All airline safety departments would require this information immediately.
To the best of my recollection, Airbus has always issued updates on major accidents when there is any development, such as the downloading of the DFDR. Clearly the info downloaded hasn't raised any flags, and this would normally need to be communicated. All airline safety departments would require this information immediately.
The standard is requested by the operators (they do have pilots and passengers to appease) Manufacturer with the approval of the investigating agency clears what is to be released. The wording is precised, no more, no less to satisfy the safety departments at the operators. It is not intended to be interpreted by the public or publicity folks.
To not have adhered to a standard protocol would have started many more rumors.
The problem is with the source providing interpretation to the press and the press going for a scoop.
In my experience the more reliable press would have gone to the BEA for clarification or at least cited the sources of balanced interpretations.
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Lonewolf... Investigations do indeed usually reveal one or more contributing factors that combine for the final outcome rather than just one single cause. I've also wondered about your question ".. why were they not able to regain control?
They had 30,000+ feet in which to do so, based on FL selected." The ACARS message at 2:12 seems to hint at an upset with the loss of the laser ring gyro integrity. I wonder how much simulator time on upset recovery is spent by flight crews? Avoidance of those situations is certainly stressed, but when it happens on a bumpy night in the middle of a cell with nothing to see outside the cockpit, that is a daunting task to put on anyone. The question still remains on how exactly they got to that point.
They had 30,000+ feet in which to do so, based on FL selected." The ACARS message at 2:12 seems to hint at an upset with the loss of the laser ring gyro integrity. I wonder how much simulator time on upset recovery is spent by flight crews? Avoidance of those situations is certainly stressed, but when it happens on a bumpy night in the middle of a cell with nothing to see outside the cockpit, that is a daunting task to put on anyone. The question still remains on how exactly they got to that point.
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Olivier
I am posting in a timely fashion 'with permission' that there is nothing new to report. Since there is nothing to report, one could conclude that we are absolved of responsibility for anything, since anything is included in nothing.
Take a breath, open one's sensors, and enjoy. The Drama is underway, and the pilots have no allies. "Fraternite"???
To appear in high dudgeon whilst snickering sotto voce, it is a talent taught in the Boardrooms....
Are you kin to Sir Laurence??
************************************************************ ****
Since Lufty and the Spanish crew (the ones Captain Dubois chatted with pre launch) have receded into history, the number of paws holding the bag are diminishing.
To mold Public Opinion takes time, be patient......
I am posting in a timely fashion 'with permission' that there is nothing new to report. Since there is nothing to report, one could conclude that we are absolved of responsibility for anything, since anything is included in nothing.
Take a breath, open one's sensors, and enjoy. The Drama is underway, and the pilots have no allies. "Fraternite"???
To appear in high dudgeon whilst snickering sotto voce, it is a talent taught in the Boardrooms....
Are you kin to Sir Laurence??
************************************************************ ****
Since Lufty and the Spanish crew (the ones Captain Dubois chatted with pre launch) have receded into history, the number of paws holding the bag are diminishing.
To mold Public Opinion takes time, be patient......
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Originally Posted by jcjeant
The study of some BEA old investigations show clearly some "cover up" .. and in my POV .. this is a discredit for the BEA.
1) what you are claiming is "clearly" founded; at best, it is based on "rumors" of wrong doings, some being clearly unfounded or very old stories;
2) such attitude you are supposed to be condemning is exactly how one may qualify your own behavior: your pre-established judgment (this will be a cover-up) was already affirmed on day one. No need to wait and take into account how this investigation would be actually conducted in reality; as everything public and contradictory to your mis-belief can be twisted as a new proof that the BEA is covering-up something, this is quite easy. You just need to claim it loud, nobody can ever prove to you the contrary (due to cover-up of the truth).
Originally Posted by jcjeant
Note that "cover up" is not a conspiracy ... it's just hide some informations to the public.
Originally Posted by jcjeant
You must also know (or I remind you) who is the owner of the "Le Figaro" :
Dassault. And Dassault and the constructor of the AF447 A330 have tight financial link.
Dassault. And Dassault and the constructor of the AF447 A330 have tight financial link.
Originally Posted by jcjeant
You can even suppose that the leak come in fact from the BEA .. or Airbus.
They can disapprove after the release of the article (this article was pasted in all the main french newspapers) but this will still in the mind of the general public and that exactly the same behavior you describe .....
They can disapprove after the release of the article (this article was pasted in all the main french newspapers) but this will still in the mind of the general public and that exactly the same behavior you describe .....
Did your read those people reaction to those papers?
How is that story making any "good" for Airbus, BEA, Dassault, Whoever you think, except for this so-called journalist and those paper printers? Even Le Figaro will end in deep embarasment after publishing so poorly researched papers in their front page. This can not be called an investigation and certainly not first class journalism: a big provocative headline, but strictly no content after the first line and very weak points barely adressing the claims. The end news is what we knew for the first hour: AF 447 flew in a storm, something wrong here!
Originally Posted by jcjeant
It's a way to prepare the public to accept the fact that in their next official BEA report ... crew will be pointed as making errors.
At least it's a possible scenario I can't discard.
At least it's a possible scenario I can't discard.
Maybe you may believe that those French people are stupid enough to read: "Scoop: Airbus will be cleared: it is all pilots and company fault" followed by strictly nothing proving the point? while, at the same time, everybody know that those data deep analysis was not even started.
Beside your bias, nothing of what one should realise about how much progress was made for AF 447, towards a far better transparency in investigation, never transpired in one single post of you. You are so zealously reporting everything seeming "so suspicious" to you that the only question it will rise at the end is about your own motivations.
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widebody and lomapaseo, if the preliminary read of the FDR had indicated unreliable air speed perhaps associated with pitot failure, would Airbus (or Boeing or Dassault) have sent out the telex phrased as Airbus did?
I realize that you may not know the answer to that question, but I would assume such telexes are supposed to convey the totality of the information obtained from the reading of the FDR, not just any 'new' information that was not previously covered by an antecedent telex.
As I said before, knowledge of a negative can itself be knowledge, and from such, people, like reporters for Figaro, start drawing inferences.
I realize that you may not know the answer to that question, but I would assume such telexes are supposed to convey the totality of the information obtained from the reading of the FDR, not just any 'new' information that was not previously covered by an antecedent telex.
As I said before, knowledge of a negative can itself be knowledge, and from such, people, like reporters for Figaro, start drawing inferences.
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IO540 :
I would -much- prefer to design a system that had a static 6000psi pressure than one with dynamic pressures.
Think about the postulated O ring, with static pressure it will deform once at get squished (technical term that) into all the tiny bumps and nicks.
With a dynamic load it will have to do this many times, each cycle will result in (very tiny) degradation, with microscopic amounts of salt water getting a bit farther in each time.
BTW: There are many methods other than O rings to seal something that does not require frequent, if any, access.
Lastly on leaky hydraulics: Most of the leaks are at sliding seals, if you think sealing an enclosure is hard ponder a shiny rod moving in and out past the seal.
-----
For BearFoil and others on the search process:
I usually find things in the last place I look, of course if you keep on looking after you find it your mental status may be in question.
Looking back it is easy to see a better way but overall I would say a fairly rational plan.
There could have been different even better plans but it is important to have a single coherent plan.
Quote:
pressures in the 6000psi region are common in hydraulic machinery.
Very true; however the 6000psi is not present 24/7 for 2 years, and it is not present anyway without leaks. Leaks are common (which is why the fluid needs topping up periodically) and are ignored unless significant.
The vast majority of hydraulics are pressurised transiently.
pressures in the 6000psi region are common in hydraulic machinery.
Very true; however the 6000psi is not present 24/7 for 2 years, and it is not present anyway without leaks. Leaks are common (which is why the fluid needs topping up periodically) and are ignored unless significant.
The vast majority of hydraulics are pressurised transiently.
Think about the postulated O ring, with static pressure it will deform once at get squished (technical term that) into all the tiny bumps and nicks.
With a dynamic load it will have to do this many times, each cycle will result in (very tiny) degradation, with microscopic amounts of salt water getting a bit farther in each time.
BTW: There are many methods other than O rings to seal something that does not require frequent, if any, access.
Lastly on leaky hydraulics: Most of the leaks are at sliding seals, if you think sealing an enclosure is hard ponder a shiny rod moving in and out past the seal.
-----
For BearFoil and others on the search process:
I usually find things in the last place I look, of course if you keep on looking after you find it your mental status may be in question.
Looking back it is easy to see a better way but overall I would say a fairly rational plan.
There could have been different even better plans but it is important to have a single coherent plan.