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AF447 wreckage found

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AF447 wreckage found

Old 14th Jul 2011, 16:08
  #2021 (permalink)  
 
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jc, it would be so crowded in that cockpit nobody would be able to see, or move. Picture a phone booth and a bunch of college students trying to set a record of how many men one can stuff into one. No way to read the PFD, for one ...
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Old 14th Jul 2011, 17:17
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Sources

Quoting RWA
"In my case, from the very first press reports on the accident, plus subsequent amplification?"
Unquote
SIGH

Wouldn"t BEA Interim report 1 and 2 be a better source of information?
Quoting BEA Interim reports 1 and 2:
"twenty-four automatic maintenance messages were received between 2 h 10 and 2 h15 via the ACARS system. These messages show inconsistency between the measured speeds as well as the associated consequences,"
Unquote

Nowhere is there a mention of ATTITUDE information problems.
Do not mislead yourself by thinking that FLAGS on the PFD mean that there is a problem with ATTITUDE INDICATION. An FD flag means, NO FLIGHT DIRECTOR, an FPV flag mean NO FLIGHT PATH VECTOR, etcetera.
The PFD in fact is a display that combines MANY flight instruments and annunciations in one display screen. The attitude instrument has not been reported as faulty in any way.
Have a look at Interim report 2, page 36 and onwards (pdf page numbering, otherwise page 35 and onwards, if you look at the report numbering - the pdf counts the cover page as a page, the report text doesn't). Report can be found on the BEA site.

Attitude indications are compared (by a COMPARATOR) between the three Inertial Reference Units. Absence of any ATTITUDE FAILURE indications mean, with a fair amount of certainty, that there were no problems with the ATTITUDE INFORMATION.
That the aircraft somehow ended up in a problematic attitude, 15 degrees nose up above FL350, is a completely different subject.

On page 48 (pdf count) of mentioned report, you find an illustration of a PFD with failure flags - in that picture, you have a completely functional attitude indication, any pilot should be able to work with that, and see through the multitude of failure flags.
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Old 14th Jul 2011, 17:17
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So, did it crash because the system allowed most if not all data to the pilots to be false in this situation?

Is it a good thing that when you want to input a control movement you are in essence asking a computer permission, and if permission is granted it may or may not be exactly what you thought you wanted. (For you and your passengers own good of course)

Is our own training lacking in some way? Are we getting away from the basics and if we are is it a step in the right direction?

The "failures" that are distilled from the ACARS messages have been explained a long time ago: systems report OWN failures, but also failures FROM OTHER SYSTEMS, with whom they communicate. Because of that setup, you may encounter the system identifiers IR1, IR2 and IR3 in situations where,e.g. the Air Data units are faulty.
Is the system overall so complicated that a mere human cannot fully comprehend all of the scenarios thrown his way and if so what are we doing in the cockpit anyway? We are safety pilots for what?

Are we so far ahead of the game that we have lapped ourselves and now behind again?

Hi,

Can I suggest that if all participants in this theater were all together in the cockpit of the 447 the night of the event .. the end of the flight would be the same (splash)
I would like to think that this very moment those pilots are satisfied that they know they did everything correctly and to the extent of their abilities and it was the system that let them down.
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Old 14th Jul 2011, 17:57
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Theories

EMIT (or anyone else willing to stick their neck out)


Reasons Why "Generally" Stick Back for Final Mintues?
  1. Failure to recognize stall condition (PF responded correctly to the first stall but not subsequent stall).
  2. Correcting for perceived overspeed/dive.
  3. Ignored flight attitude data.
  4. THS trim interferance?
  5. Pilots executed wrong stall recovery procedure although they did it right the first time ???
  6. Failed flight attitude data on PFDs, no backup steam guage style AI instrument installed. [A330 ADIRU failures: 21 May 2009 Miami-Sao Paulo TAM Flight 8091 registered as PT-MVB and on a 23 June 2009 Hong Kong-Tokyo Northwest Airlines Flight 8 registered as N805NW]
  7. Sidestick input fault with nose up bias. Failure to diagnose and overide.

Last edited by xcitation; 15th Jul 2011 at 21:03.
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Old 14th Jul 2011, 18:02
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Theory

xcitation

Your numbers 1 (excluding bracketed text) and 3 score high on my shortlist.
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Old 14th Jul 2011, 18:13
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So, did it crash because the system allowed most if not all data to the pilots to be false in this situation?
Perhaps it's time to revisit the Bea note:

2 h 10 min 05: (...) The recorded parameters show a sharp fall from about 275 kt to 60 kt in the speed displayed on the left primary flight display (PFD), then a few moments later in the speed displayed on the integrated standby instrument system (ISIS).

2 h 10 min 16: (...) The speed displayed on the left side increased sharply to 215 kt (Mach 0.68).
(...)

2 h 10 min 51: (...) Around fifteen seconds later, the speed displayed on the ISIS increased sharply towards 185 kt; it was then consistent with the other recorded speed.
(...)
Note: The inconsistency between the speeds displayed on the left side and on the ISIS lasted a little less than one minute.


From all we know, they temporarily lost airspeed.

Is it a good thing that when you want to input a control movement you are in essence asking a computer permission, and if permission is granted it may or may not be exactly what you thought you wanted. (For you and your passengers own good of course)
At which point do you suggest the plane didn't do what the pilot asked from it because of the FCS?

Is the system overall so complicated that a mere human cannot fully comprehend all of the scenarios thrown his way and if so what are we doing in the cockpit anyway?
EMIT was talking about Acars messages. They're used to confuse technicians, not pilots...
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Old 14th Jul 2011, 20:37
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IMHO, pilots didnīt fail to recognize their compromised situation.
Rather, I think they were dealing with a confused system, which missed the right
"law" switch or state change to begin with!
Bad training (read = arrogant position taken by manufacturers and company policies), contributed for sure!
The training based on following automatics improved the waste of time, wich at the end killed them all.
When the Captain reentered the cockpit the power plant was set at idle and nose-down inputs were fed...
So: Why?
Why power idle and change of pitch?

Well, I think they knew (or the Captain did), the best way to make a compromise with the (for them unkwon), airspeed was to make a glider of the aircraft.
Going back to the basics thus...
They just missed the Trim Wheel... And when they were on the right path to solve the problem, automation began blaring stall and confused them even more...
Who knows... Maybe it was far more worse than we can imagine...
I my eyes they knew their status, only FL370 is way to short to react well when your rate of descent is 10K feet/m.

And... If I had been a pax on AF447, sure I had tried, crawled on the roof if needed, with all the negative gīs on my ass to the cockpit to tell the pilots they had to decrease their AoA as soon as they could...
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Old 14th Jul 2011, 22:35
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When the AP and AT failed would the plane have just flown straight and level with the last power setting before it disconnected? If there was an erroneous overspeed would the disconnected AP pitch up?

My neighbor says the Airbus autopilot is on even when disconnected to maintain pitch and bank. I recall it being brought up a few hundred posts ago so sorry if this has been hashed out before. I had another arguement with him last night because he said if the AP is off it is still flying the airplane using your control stick inputs. I said if you can get out of your seat and go in the back how can you say the AP is off. It might be in the basic CWS mode of the Boeing but for that you need the AP on.
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Old 15th Jul 2011, 00:17
  #2029 (permalink)  
 
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bubbers44;
if the AP is off it is still flying the airplane using your control stick inputs.
This is what was meant:-

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Old 15th Jul 2011, 01:13
  #2030 (permalink)  
 
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Can I suggest that if all participants in this theater were all together in the cockpit of the 447 the night of the event .. the end of the flight would be the same (splash)
and then:

jc, it would be so crowded in that cockpit nobody would be able to see, or move. Picture a phone booth and a bunch of college students trying to set a record of how many men one can stuff into one. No way to read the PFD, for one
Hypothetically it may just have made the difference needed for a different outcome and in a manner not envisaged so far.
The CG of the aircraft (which seems to have lost pretty well all means of aerodynamic and control authority) would have been brought forward to the degree that the seesaw effect might cause the nose to drop to the point where the aircraft starts to move forwards again. Effective airspeed would be recovered and a faint hope for resumption of normal flight presented. It wouldn't be pretty or pleasant and the end result may well have been the same.

All hypothetical of course.
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Old 15th Jul 2011, 02:46
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At which point do you suggest the plane didn't do what the pilot asked from it because of the FCS?
There was that A320 that flew into the trees after the pilots performed a low pass...


EMIT was talking about Acars messages. They're used to confuse technicians, not pilots...
Mine was strictly a rhetorical question.
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Old 15th Jul 2011, 07:02
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There was that A320 that flew into the trees after the pilots performed a low pass...
Without going into another of those discussions, where do you suppose might be parallels to AF447 (besides an A plane being involved)?

Mine was strictly a rhetorical question
I know. But is some internet experts getting Acars messages wrong a good case in point for your answer?
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Old 15th Jul 2011, 13:34
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Without going into another of those discussions, where do you suppose might be parallels to AF447 (besides an A plane being involved)?
Both flights utilized an aircraft that was strictly FBW. All I am saying in general the system is designed to fly the aircraft better then the pilots and tell me if I am wrong here but it does have the capability to negate pilots actions. (The friggen A320 in the trees) I was not aboard flight 447 and neither were you so I do not know if there was an exact parallel however you are still controlling (somewhat) a system that is controlling the aircraft. Remember the designers have designed the system to be better then you and in doing so gave the system (whether inherent or by design) the ability to override what you ask of it. It knows best right? And I do think in a lot of cases it probably does know best since a lot of the pilots now have limited flying skills. But there is going to be that one hundredth of one percent that the software designer did not cover or the friggen hardware craps out and you you have between your hands and the control surfaces are some useless wires.
I like automation, with it I can relax a bit and in doing so I can better see the big picture. Hand flying at flight level does suck. (I flew cargo so yes we tried it on occasion) Are you totally comfortable of not have 100% control of the aircraft? I do stand by my original statement though; I do not mind FBW as long as the wires are in control tubes.

I know. But is some internet experts getting Acars messages wrong a good case in point for your answer?
I do not fully understand your question (Or is it a statement with a question mark?) I am not an "internet expert" nor am I am expert in flying. I have been flying professionally since 1982, a healthy mix of military, law enforcement and commercial and presently instructing in the desert. So I have almost 30 years of experience, most of which have been successful, have not killed anyone by accident and not bent any sheet metal.
I am not here to compare experiences, time, licenses, type rating anything with you nor do I need to. I have not met any aircraft that can read whats is on the back of my piece of plastic. Well maybe your FBW one can. There is nothing (yet) that can replace experience and sound judgement. I am just giving my opinion.

Last edited by before landing check list; 15th Jul 2011 at 15:11.
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Old 15th Jul 2011, 15:15
  #2034 (permalink)  
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(quoting 'before landing checklist':-

Remember the designers have designed the system to be better then you and in doing so gave the system (whether inherent or by design) the ability to override what you ask of it. It knows best right?

And I do think in a lot of cases it probably does know best since a lot of the pilots now have limited flying skills.
From much less experience, 'before landing checklist,' in my personal experience as a mere amateur flyer, I couldn't agree more. Both main manufacturers and the airlines are leaning more and more towards a situation where the 'systems' hold sway and the pilots are virtually forbidden to fly manually, unless they take the risk of being charged with anything from 'gross negligence' to 'manslaughter' if anything goes wrong.......

It's worth bearing in mind, too, that the 'first duty' of flightcrews nowadays is 'listening to the systems.' Someone above mentioned that the AF447 pilots shouldn't have taken as much as ten seconds or so before reacting to the 'zoom-climb' - it's fair to say that, as far as I know, the flight-crew's first duty would have been to 'plough through' all the error messages, one by one, with the PNF reading them out and the PF acknowledging and clearing them, before they actually DID anything about them.......

Sadly, I suspect that when (and if) the BEA finally comes clean and publishes the full CVR transcript, we'll hear that the flightcrew literally didn't live long enough to get through 'tic-tacking' on all those messages.......

My own view is - and always has been - that the pilot should always have the final say. And, further, that if a given aeroplane can't be safely flown manually in all conditions, the answer is not to install yet more 'systems' but to 'design the b****y thing so that it works properly......'
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Old 15th Jul 2011, 16:58
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Originally Posted by RWA
I couldn't agree more. Both main manufacturers and the airlines are leaning more and more towards a situation where the 'systems' hold sway and the pilots are virtually forbidden to fly manually
Nonsense. 'Systems' are there to be used by crews when appropriate just as manual flying is when appropriate.

Originally Posted by RWA
It's worth bearing in mind, too, that the 'first duty' of flightcrews nowadays is 'listening to the systems.
Wrong. The 'first duty' of crews is to fly the aircraft. Whether that is done manually or via the 'systems' you tell the aircraft what you want and then monitor the response.

Originally Posted by RWA
it's fair to say that, as far as I know, the flight-crew's first duty would have been to 'plough through' all the error messages, one by one, with the PNF reading them out and the PF acknowledging and clearing them, before they actually DID anything about them.......
Then you don't know very far. The 'first duty' of any crew is to fly the aircraft. Any other actions are secondary and are to be performed when not interfering with flying the aircraft.

Being a mere amateur you are perhaps excused, but with the amount of nonsense already posted there is no need to add more.
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Old 15th Jul 2011, 17:25
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Originally Posted by Bearfoil
Something
Zero-value-added prose, as someone already noted before.
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Old 15th Jul 2011, 18:24
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Despite all the more than 100 pages with remarks and replies: still asking myself: why did they fly into a level 5 CB? What radarsystem was in this aircraft?

In a CB you can expect anything, so how the aircraft behaved could have been far beyond its design-limits.
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Old 15th Jul 2011, 21:01
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The mysterious zoom climb

Why the zoom climb?

It's very odd to me that all of the blogs seem to overlook that all of this happened at the very same time AF447 entered a monstrous thunderstorm. Which contains serious up and downdrafts and consistant warnings for pilots to avoid them.

There is enough evidence to indicate hand flying the A330 at altitude is dicey at best even on a clear day, let alone in turbulence, at night, and with no airspeed indications.

All the other aircraft in the area deviated. Why not this one?
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Old 15th Jul 2011, 21:12
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still asking myself: why did they fly into a level 5 CB?
All the other aircraft in the area deviated. Why not this one?

Two posts in a row state as facts about the aircraft flight into a defined thunderstorm without deviation.

I challenge those facts

Where's the investigative data that so states?

To continually speculate for a simple explanation does nothing to furthur the understanding of a complex accident.
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Old 15th Jul 2011, 21:27
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Henri737 and wallybird7,

There has been a back and forth conversation on this forum about whether they flew into a Cb.

I think perhaps the minimum level of agreement by parties engaged in this conversation is that AF 447, at night with the moon aft, flew into a cloud that had sufficient ice crystals at FL 350 to quickly clog the pitots. There is no consensus on the degree and duration of any turbulence encountered, nor of the existence of updrafts, etc. I believe there is consensus there was no lightning. I don't believe there is agreement on what kind of cloud in the ITCZ might produce ice crystals at FL 350.

Presumably, the next BEA report will soon enlighten us all.
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