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AF447 wreckage found

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AF447 wreckage found

Old 30th Jul 2011, 01:49
  #2281 (permalink)  
 
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Originally Posted by Bearfoil
just this once, then I'am off for vacation
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Old 30th Jul 2011, 02:50
  #2282 (permalink)  
 
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Posted by Doze
This is all about how the human brain reacts under pressure and stress, and the truth is that none of us can know how we'll react in a situation that perilous until we're confronted with it.
Humans… Rare entities are those… Aren´t they Doze?
Anyhow… I´m overwhelm with the grace society degrades…
We all degrade in the same graceful way. Economy degrades graceful pulling everybody in its way down, with its poor philosophy and short-minded short-term get it all, get it fast! dogma.
“Graceful degrading systems” and their redundancy have shown that they aren´t able to cope with nature… They all kicked off and gave the “bad trained pilots” the joystick… Very graceful degrade strategy indeed… A mirror of the self made, bad communication and … culture.
Radar catching-up bad weather (way before bad weather becomes an issue), becomes degraded, certainly at the moment an ETOPS ops is going on. Super Cold water? What is that? Satellites monitoring and pitot tubes designed to cope with… What? What was their task? Well, I would say awesome performance in graceful degrade!
Graceful companies and developers all the way down, which keep pilots as slaves afraid to talk?
Just give me a graceful break will you!
Nobody here is against automation and development methinks. Rather we all are seeking for an answer. The answer which came from BEA nevertheless, is more than I´d expected…
I truly hope ALL pilot unions around the world will discuss this event deeply in order to improve aviation to it best.
It isn´t only an AF issue… It seems to me a worldwide policy instead…


I´m thankful to all of you, which during this long passing years, kept their minds sharp and were seeking for an answer. Also thanks to this forum which made it possible!
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Old 30th Jul 2011, 03:33
  #2283 (permalink)  
 
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Not at all sir. I suggest you read what I'm actually saying (and have said consistently on here for 5 years) before tarring me with that brush. I have always said it is *imperative* that basic stick-and-rudder skills be maintained and that pilots should have a knowledge base relating to the type or types they are operating that is as complete as humanly possible. I think it's dispiriting and borderline scandalous that the airline industry sometimes treats its crews with so little respect and that it is as engaged in the "race to the bottom" as any other industry you care to name - see a rant I made on this very topic here:
DW you are right about this and I apologize for my comment. I also do not mean to come across that the pilots on flight 447 were in anyway incompetent. That would not be fair at all since I was not there and whom am I to judge. I do not like the system nor the training department. You have to know that throughout the whole incident those pilots used every ounce of their collective knowledge and experience and this one time it was not enough.
Could I have done any better? I am 53 years old and still flying. Luckily I have reached the point to be able to say I am not as good as one time I pretended to be. I know now the system (training department) does not and cannot cover all the bases and since we know this we must try to cover the gaps the best that we can. That is our responsibility we have to ourselves, each other and to the passengers who fly with us.
No, maybe I could not or would not have done better. We are only speculating here and that is not really bad since we are learning still (whether we admit it or not) from each other. I have never been in an unknown situation (flying or not) for that long amount of time with all those insidious conflicting information, we really do not know how we would have reacted especially when you throw in the "dark and stormy" bit with several hundred people in the back. Sometimes simulators do not simulate very well since that cannot simulate real fear other then the fear of your loss of ticket. Not the same at all is it?
Until bean counters quit ruling the earth which I do not think is going to happen anytime soon we have to stick together and do the best we can with the crap we are given.

Good day gentlemen.
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Old 30th Jul 2011, 03:50
  #2284 (permalink)  
 
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If you had old style fixed wing military pilots the aircraft would never have been lost. All these aircraft need a magic switch that, when it is turned on, the aircraft turns into a basic stick handling machine.
I do not think this is a totally fair statement. Fortunately I have about have my time divided between military and civilian flying. I have seen gross muck ups on both sides. The military does seem to lack in imagination (as a very general rule so don't yell at me) and the civilians (Again as a very general rule so don't yell at me) sometimes lack in consistency in training.
It is our job as individuals as we mature is to see these faults in ourselves and fix them the best as we can. We need to take recurrent (even initial) courses ourselves from outside sources, try your hand at another type of flying (not as a job mind you but with a friend or just pay out of your own pocket. We should try to see outside of our ruts and think about what we see.

Last edited by before landing check list; 30th Jul 2011 at 07:45.
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Old 30th Jul 2011, 07:33
  #2285 (permalink)  
 
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Takata, pardon ma inexpérience: is that a flap actuator or a stabilizer one?

Merci
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Old 30th Jul 2011, 07:43
  #2286 (permalink)  
 
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Image at 2286

Is that screw shaft bent?
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Old 30th Jul 2011, 09:27
  #2287 (permalink)  
 
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The copilots had received no high altitude training for the "Unreliable IAS" procedure and manual aircraft handling
BEA

I am only repeating what has already been discussed but the thread is so long,its hard to find the fundamentals and keep your bearings.AeroCaraibe suffered an almost identical incident(s) just prior to AF447 and a lengthy report was issued.Same Aircraft,same pitots,same icing encounter,same language.Why then was it not disseminated,digested and trained on?

The key line in the AeroCaraibe report(French language only) says:
"En effet,le 'PF' est intimement persuade que les deux alarmes 'STALL' sont inappropriees.C'est volontairement qu'il ne tient pas compte de la phrase 'RESPECT STALL WARNING AND DISREGARD RISK OF UNDUE STALL WARNING STATUS MESSAGE IF DISPLAYED ON ECAM."

The AeroCaraibe pilot used a KNOWLEDGE-BASED response to loss of airpseed and spurious STALL warning associated with pitot icing.Fly pitch and power,2.5 deg ANU and 82% N1.My question is that even if the AF PF was unable to disbelieve his instruments and ignore any spurious warning,why did he pitch the aircraft to 10deg+ ANU?At FL350???Would not the instinct be to fly TOGA and 0-2.5 ANU pitch?And then find himself in overspeed after the icing clears(only 50 seconds)?This is very confusing.Someone said that FBW pilots apply TOGA and full ANU on the stick in response to stall.Now he acknowledges ALT LAW(ie.a/c can stall unprotected..is that right?) yet goes for 10+ANU pitch at 35000 feet?
Pitot-static anomalies are not easy for pilots;you have to ignore your instruments affected by the blocked sensor and maintain concentration on pitch/power through a cacophony of aural/visual alerts,some valid,some not.Experienced crews have been flummoxed by conflicting information as seen in Aeroperu and Birgenair.Use a rule-based response at your own peril.But those crews did exactly that.And there was a Captain sitting in the left seat on both flights,although an umbrella of suspicion is certainly cast over the quality of the Birgenair crew(he continued the takeoff with an AS disagree).

The two Airbus anomalies here(THS stuck at 13ANU and stall inhibited below 60),although contentious,should never ever have come into play.Lets assume that we cant expect two co-pilots to apply a KNOWLEDGE-BASED response to a high altitude unreliable airspeed event at night over the Atlantic.They are fooled by the conflicting information despite the fact that they knew they were flying at M.8 just moments prior.They now believe they're in a stall.They believe whats presented in front of them.Then there should not have been any ANU pitch command and hence no auto trim to 13 degrees,no speed(real) decay and no possibility whatsoever of stall inhibit.They should have found themsleves in an overspeed condition after the pitot unblocked which may/may not have led to inflight break-up.This would have been plausible,even forgiveable.All they had to do was do what the AeroCaraibe crew did.Set 81% N1 and put the nose just above the horizon.It was flying before with those settings,it will continue to do so.
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Old 30th Jul 2011, 09:51
  #2288 (permalink)  
 
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Please look at the BEA website.
There is a new press statement/synthesis of the accident. There is also some recommendations regarding pilot training for high alt stalls, and a recommendation that all aircraft display A of A data.

Personally, I'm concerned at the absence of comment on pilot/aircraft interface factors- in particular, regarding the loss of speed data resulting in a situation where correct stall recovery actions appear to have led to a reactivation of the stall warning. At that moment, it seemed to be the last chance for these poor people.

My friends in the industry none the less assure me that fyling attitude strictly, with minimal changes to any control inputs, would have saved the day.

I would also be interested in any comments as to how the alarm/alert system may interact with a disorientated pilot to produce responses that generate additional risk in emergency situations.
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Old 30th Jul 2011, 10:31
  #2289 (permalink)  
 
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Hi Poire,
Originally Posted by Poire
Takata, pardon ma inexpérience: is that a flap actuator or a stabilizer one?
THS screw and actuator... and it was a test in order to verify that Bearfoil was really off for vacation. (He could not have refrained from posting as he is quite obsessed with this piece of metal).
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Old 30th Jul 2011, 12:57
  #2290 (permalink)  
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I also do not mean to come across that the pilots on flight 447 were in anyway incompetent.
Seems you don't have to. But, it's so, so easy to fly those last few minutes from the comfort of one's armchair. It must have been enough to throw a good mind into chaos for a moment or two, but for those with very limited time handling real hardware in extreme conditions, it seems what they had in front of them was more than they could unravel. It takes a lot of willpower to shut out a vista of sophisticated equipment and concentrate on one small and comparatively primitive device.


BBC News - Air France Rio crash: Pilots 'lacked training'
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Old 30th Jul 2011, 13:57
  #2291 (permalink)  

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Sorry, very ignorant person confused here.

Did they not have an attitude indicator/artificial horizon working (I thought that they did)? Would that not have shown that they were markedly pitched up and given them a clue to what was going on?
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Old 30th Jul 2011, 14:30
  #2292 (permalink)  
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As far as I know after some weeks torn from the internet, the standby horizon was unaffected by the computer derived errors. Although the main systems were probably okay, the idea of the standby is that its power supply should be maintained and its internal workings unaffected by the plethora of information inputs. If in doubt, check that little unit.

Just a video of a random 330. Start just after a minute in. Worth looking at the scan of first the standby horizon, then captain's screen, then it goes through standby to the right. A bank has been started.

Even the standby is electronic. I would love to see a gyro in there somewhere.



Probably a translation plus press-speak, but some of the dialog must be from the transcripts. Totally horrifying.


Cockpit terror of jet's 38,000ft death plunge - News, Frontpage - Herald.ie
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Old 30th Jul 2011, 15:49
  #2293 (permalink)  
 
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Just reading the NY Times report on this (http://goo.gl/IKmQy), which ends with a paragraph that says:

Since the accident, both Airbus and Boeing have modified stall-recovery procedures with guidance from safety regulators in the United States and Europe. Safety experts say those procedures now instruct pilots to first lower the nose of the aircraft, regardless of altitude, and, if necessary, reduce thrust to avoid excessive acceleration. Previously, the standard procedure when nearing a low altitude stall was to raise the nose by around 5 degrees and maintain thrust.
First, this just so elemental it seems to be rediculous. But that last sentence really surprised me. In my extremely limited experience as a GA pilot, I was always taught that the first thing you do when approaching a stall is lower the nose. Can someone explain why the "standard procedure" has been to raise the nose?
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Old 30th Jul 2011, 16:04
  #2294 (permalink)  
 
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Originally Posted by Loose rivets View Post
As far as I know after some weeks torn from the internet, the standby horizon was unaffected by the computer derived errors. Although the main systems were probably okay....
So far there are no 'hints' either that the main attitude displays were affected at all.
...the idea of the standby is that its power supply should be maintained and its internal workings unaffected by the plethora of information inputs. If in doubt, check that little unit.
Not relevant here, but the "old-fashioned" electro-mechanical standby AH would remain stable and reliable (because of the high gyro rotor speed) for minutes after everything else went "kerplunk". It's still credited with saving a Caravelle when the entire electric systems went belly-up.

----

Just a video of a random 330.
Not quite random, since it has an independent 3-inch standby A/I. The AF A330 that crashed had an "ISIS", a bigger standby 'instrument cluster' on a separate screen (there should be a photo somewhere on this or the other AF447 thread). Hence I assume the video was not of an Air France A330.

Even the standby is electronic. I would love to see a gyro in there somewhere.
I don't know what the type/manufacturer of that particular standby A/I is.
But I think that you'll discover the old and well-known fully electro-mechanical SFENAs have now left the stage, but that behind that electronic display there's still an independent gyro. Switching to an electronic display just made the mechanical bits simpler....

Probably a translation plus press-speak, but some of the dialog must be from the transcripts. Totally horrifying.
The dialogue that the Herald quotes is indeed based on translated excerpts from the transcripts.
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Old 30th Jul 2011, 16:06
  #2295 (permalink)  
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Can someone explain why the "standard procedure" has been to raise the nose?
I believe the (flawed) training analysis is along the lines that if you learn to recognize the onset of the stall early enough, then an increase in thrust (and hence airspeed) will fly you out of the stall threshold WITHOUT any reduction in altitude or requirement for a nose down attitude.

The flaw in this training philosophy is that it assumes you will always recognize and react at early stall onset, so the full stall never develops. If you never couple this training with full stall recovery techniques, eventually pilots end up not knowing what to do if a full stall develops.

This originates in flawed training analysis where the fear of losing any height at all during stall recovery on an approach has the effect of removing the basic skills required to recover from a fully developed stall.
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Old 30th Jul 2011, 17:41
  #2296 (permalink)  
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Yes, I think it is based however, on a full compliment of engines running at say, cruise power, and an attitude that wouldn't be that much of a change when hurriedly pulling to +5. The power increment could then be metered out by erm, skilled judgment.

The crew were perhaps dealing with not only vigorous turbulence, but also more than a few man-made excursions from the horizontal. Also trying to recognize a stall with massive lifting and down-droughts would certainly be very much more difficult. Stalled one moment, and flying with reduced wing loading the next.


What I find hard to understand is the 'Deep Stall' nature of this decent. There does not seem to have been a succession of conventional stalls, yet the aircraft is not one of the T tailed types that could lock one into such a decent. I can only conclude a lot of time was spent with the systems blurring the issue, indeed applying power with vectored thrust 'shaping' the angle of stabilization to some deceptive angle.

Is there a clear recording of the flight-deck ambient noise? Once height was reduced enough to give a good gap between stall speed and overspeed, the ambient noise would have been quite different. The silence should have been deafening.
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Old 30th Jul 2011, 19:07
  #2297 (permalink)  
 
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The previous recovery procedure was based on the fact that all widebody aircraft with hi bypass engines is capable of stall recovery with minimal altitude loss due to quick engine response and massive thrust. If slats is extended at the same time the aircraft can be flown out of the stall without altitude loss if at low level.

An A330 in degraded law at high altitude stalls at 7 degrees AoA (vs 15 degrees at low altitude), max thrust = climb thrust, and the recovery pitch is somewhere between 0 to -5 degrees and requires 4000´if done correctly. If you do not initiate recovery promptly, but hold the stick back, lack of elevator response will cause the THS to trim nose up, just as the report suggest.

In this situation, if the AoA becomes extreme, you may have to use rudder to get the nose down, and it takes a very low nose down attitude to unload and regain airflow.

Now, with this attitude (more than 20 degrees n.d.), once the airflow is back, the acceleration is huge - especially in manual TOGA - and you [B]must[B] start a smooth recovery immediately while avoiding over-stress ( fortunately the Airbusses have g-meters), secondary stalls and Vmo excursion. Vd excursion with structural failure is a distinct risk.

Recently, we have done the AF profile a number of times in a very good CAE SIM: recovery is possible at 37000´if done properly. After holding the stick back and letting the THS trim aft, the ensuing deep stall is IMHO not recoverable for the average line pilot, and that brings up a new question:

To which extreme situations shall we select and train commercial line pilots?

Oh, we all want to keep our cosy straight-and-level job, and the operator just want to fill a seat, so the mental break point SIM assessments has gone out of fashion, and no one knows if the co-pilot is really up to it, if the poop hits the fan.

What is left is training, and while some operators are doing a great job, some are not, partly because proper high altitude recovery training takes time, and the allocated training time is already full of NPA, V1 cuts, ECAM work, Evacuations etc. etc.....

Hopefully this tragic event will trigger some thoughts in the training departments and among the regulators, so we can swop some of the endless checklist reading with some hands-on training. Getting extra time....? In your dreams.....

And BTW, 25 years ago I initiated a hi-level training program for the old captains; many of them didn´t have a clue of what was going on up there unless they had survived a tour on one of the "interesting" fighter types of the day, and only a few of them had actually recovered from a stall in the Starfighter, the Phantom, the Lightning or the Mirage.
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Old 30th Jul 2011, 21:23
  #2298 (permalink)  


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Correct me if I am wrong (I'm sure someone will!) but I thought the revised stall recovery was as a consequence of the 737 stall on approach into Bournemouth and similar incidents which application of TOGA could cause an uncontrollable pitch couple especially if out of trim?
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Old 30th Jul 2011, 22:47
  #2299 (permalink)  
 
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B4-Landing said:
Until bean counters quit ruling the earth which I do not think is going to happen anytime soon we have to stick together and do the best we can with the crap we are given.
Thanks B4
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Old 30th Jul 2011, 23:21
  #2300 (permalink)  
 
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Originally Posted by Loose rivets
The crew were perhaps dealing with not only vigorous turbulence
Vertical acceleration trace is not consistent with flying through turbulence. There is +1.6 G spike as the aeroplane starts its climb, after that, it remains between +1.25 and +0.7G for the remainder of the flight.

Originally Posted by Loose rivets
What I find hard to understand is the 'Deep Stall' nature of this decent.
Trimmable horizontal stabilizer went to maximum nose up deflection. For most of the upset, both elevators were at their maximum nose-up deflection, too. Twice they start moving towards nose-down, first prompted by command from RH stick, second time by LH, but they only get halfway to neutral before new pull on the sidestick sends them back to their NU stops. Seemingly FBW was in Altn law so elevators were trying to satisfy G demand from pilot controls. It goes to show that even when there's no direct stick displacement to control deflection things work out in quite conventional way.
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