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hulotte
3rd Aug 2011, 05:42
On AIRBUS

Side stick are fitted with priority button wich allow neutralizing other side stick when operated associated with call " PRIORITY L or R

Its not allowed using both side stick a the same time, in case if not there is also a call "DUAL INPUT"

On pedestal close to throtlle both side a big wheel trim for manual setting wich is also operating automatically .

cwatters
3rd Aug 2011, 09:00
If they felt they were fast and descending perhaps they thought this was a high speed stall warning? In which case relaxing the back stick but still mantaining some might make sense.

GerardC
3rd Aug 2011, 10:15
Intruder, please do some home work :
Does the Airbus have a stab trim button on the sidestick? NO !

there was PLENTY of time to get the airplane out of the stall YES !

they failed to even make a reasonable attempt to do that. Each time they made a "reasonnable attempt" to solve their problem (ND), the stall warning kicked in again and THAT is VERY, VERY sad !

threemiles
3rd Aug 2011, 12:01
IMHO the ignorance of the audible stall warning could only be caused by the pilots assuming, that the stall warning would be triggered by too low speed (instead of AoA).

Speed incorrect -> Stall warning -> ignore it

When the speed came back they had stalled the plane and the speed stayed low => assumption: still incorrect.
Why should they believe now, that the speed was more correct than before?
Why should they believe with all this confusing stuff around them, that any other indication was more correct?
The speed even became lower and lower and the stall warning disappeared at some point. -> continue to ignore all this

It remains the question: why did he pull so much? where is the no speed indication check list, and so on.

Also: pitch is not AoA!

Kalium Chloride
3rd Aug 2011, 12:15
The real kicker, I suspect, is the timing of the captain's re-entry to the cockpit - almost exactly at the point where the continuous stall alarm switched off. I wonder what he would have done if he'd heard nearly a minute's worth of stall warning.

DozyWannabe
3rd Aug 2011, 12:24
Each time they made a "reasonnable attempt" to solve their problem (ND), the stall warning kicked in again and THAT is VERY, VERY sad !

Not true : see http://www.pprune.org/rumours-news/447730-af447-wreckage-found-124.html#post6615592 .

Only once does the return of the stall warning match a nose-down input (2:12-35-2:12:38). In all other cases the stick is either neutral or back when the stall warning returns, except for once at the very end, where the PNF has already been more-or-less holding nose-down for 15 seconds.

@Mimpe - The Hudson aircraft was an A320. Also, while Sullenberger had the piloting chops that ditched them safely in the river, he was the first to praise F/O Skiles and the rest of his crew for a correct and professional response to the situation.

Mimpe
3rd Aug 2011, 12:52
lonewolf...my concern is that PF may well have been more than just worried about overpeed.Its clear he had lost his initial crucial scan,was overcontrolling, and I feel as the aircraft slowed with zoom climb,may well have crossed the rubicon of lapsing into a sensory interpretation of what the aircraft was doing.I feel the decleration he was experiencing in the late stages of the climb, heightened by marked anxiety,probably ended in a somatogravic illusion of acceleration, and persistent nose up inputs unto death.

The rest was history, as the situation required immediatre transfer of control to PNF, whose spatial orientation and understanding of the situation appears clearly superior throughout. No time for egalitarian social norms.

When the birds hit the 737 over Manhattan, pretty much the first action fronm Sullenberger was.." My Aircraft".

320wonder
3rd Aug 2011, 12:54
it's really sad and unfortunate

i believe if the crews had known beforehand that they had Unreliable Air Speed, they would have flown the last known power setting and Pitch, ignoring all the other warnings.... i strongly believe they were very confused...

if they had recognised it as Unreliable Air Speed earlier , and just fly Attitude + Power, and maintained it until at least out of the weather, things would have been much better.

it's not easy to recognise Unreliable Airspeed...... and getting inside some massive weather leaves you very little time to stop and think ,before confirming what's the problem...

string of unfortunate events happening at the exact moment...

Mimpe
3rd Aug 2011, 13:21
thanks for the correction Dozy.

I do remember Sullys F/O cooperated immediately and seamlessly - a great result for all. Sully's book was a wonderful read, and there was a lot to learn from it.

GerardC
3rd Aug 2011, 13:49
Originally posted by "Dozy" Not true : see AF447 wreckage found .
Only once does the return of the stall warning match a nose-down input (2:12-35-2:12:38).With respect, all the sequence between 2:12-20 and 2:13-00 is a succession of nose down inputs followed by stall warning activations followed by nose up inputs (in reaction to the alarm ?).
In all, 4 stall warning activations.
Would not YOU be confused : nose down -> stall ; nose up -> NO stall.

ross_M
3rd Aug 2011, 13:49
At 02:10:16Z the aircraft goes into "Alternate Law". What was the trigger? The faulty pitots? Just curious.

Also, after the pitots started working again why does the system not re-arm the flight envelope protections. With the narrow flight envelope at those heights it seems dangerous to subject pilots to unprotected flight for any longer than absolutely inevitable.

jcjeant
3rd Aug 2011, 13:54
Hi,

Le BEA ne prend pas en compte l'incohérence des alarmes de décrochage !? | Communiqués et conférences de presse (http://www.asso-af447.fr/Communiques-et-conferences-de-presse/le-bea-ne-prend-pas-en-compte-lincoherence-des-alarmes-de-decrochage.html)

Le BEA ne prend pas en compte l'incohérence des alarmes de décrochage !? Mise à jour le Mercredi, 03 Août 2011 10:58 Mercredi, 03 Août 2011 10:03
http://www.asso-af447.fr/templates/asso_af447_tpl/images/trans.gif http://www.asso-af447.fr/images/M_images/printButton.png (http://www.asso-af447.fr/Communiques-et-conferences-de-presse/le-bea-ne-prend-pas-en-compte-lincoherence-des-alarmes-de-decrochage/Imprimer.html)
Suite à la récente diffusion dans la presse (>> (http://www.latribune.fr/entreprises-finance/services/transport-logistique/20110802trib000640317/vol-paris-rio-le-rapport-d-enquete-a-ete-caviarde.html) lien vers l'article (http://www.latribune.fr/entreprises-finance/services/transport-logistique/20110802trib000640317/vol-paris-rio-le-rapport-d-enquete-a-ete-caviarde.html)) d’une information relative à la non publication d’une recommandation de sécurité aérienne par le Bureau d’Enquêtes et d’Analyses, l’Association Entraide & Solidarité AF447 exprime son vif mécontentement et son extrême indignation quant à cette mascarade.

En effet, malgré un délai d’analyse très court du troisième rapport du BEA, nous notons que les pertes concomitantes des données de vitesse et d’incidence génèrent une situation particulièrement critique, et que cette situation, à ce jour, n’a toujours pas été expliquée techniquement.

Ainsi, l’absence d’alarme décrochage (Stall) laisse supposer aux pilotes que la situation aérodynamique de l’appareil s’améliore, alors qu’en réalité, elle empire.

De la même manière, l’apparition de cette alarme et son respect dans le cadre de la procédure alors en vigueur, sans visualisation possible de l’incidence, conduit les pilotes à augmenter la poussée des réacteurs (TO.GA) et par conséquence, augmenter encore l’incidence de l’aéronef.

A cela, nous devons ajouter la différence de procédure « IAS Douteuse » relativement à la manoeuvre dite d’urgence (Memory Items), celle d’Air France indiquant de respecter l’alarme décrochage, alors que celle d’Airbus ne le précise pas.

Ainsi, considérant que pour des raisons de sécurité évidentes des actions immédiates doivent être entreprises, nous demandons qu’une recommandation soit émise par le BEA, pour d’une part, informer les pilotes, et d’autre part, pour adapter les procédures aux remarques précitées.
Il n’est nul besoin d’attendre les hypothétiques conclusions d’un groupe « facteurs humains » pour réagir uniquement sur des critères de bon sens.

Il est également à remarquer que les recommandations de l’autorité d’enquêtes ne sont affectées d’aucun délai de réalisation, ce qui semble incompatible avec la notion de réactivité inhérente à la sécurité aérienne.

Au vu de ces évènements à la partialité affichée, il est primordial que l'Association obtienne une réponse favorable à sa requête par voie judiciaire pour obtenir l’intégralité des données des enregistreurs de vol.

Enfin, nous condamnons fermement ce triste épisode qui jette définitivement le discrédit sur l’investigation technique et qui génère une crise de confiance sans précédent envers les autorités d’enquêtes. La précipitation avec laquelle ces autorités et ces responsables ont accusé les pilotes sans aucune réflexion préalable avait alerté notre suspicion. Nous avons maintenant confirmation que les affirmations émanant de la tutelle du BEA étaient non seulement prématurées, dépourvues d’objectivité, partiales et très orientées vers la défense d’Airbus.

Ceci est totalement indécent et inacceptable. Les victimes de l’AF447 ne méritent pas un tel outrage. Les familles de victimes dénoncent un véritable scandale, qui viole leurs droits à la vérité !...

Pour l’Association Entraide & Solidarité AF 447
Le Président
Robert Soulas
The BEA does not take into account the inconsistency of the stall warning!?

Updated on Wednesday, August 3, 2011 10:58 Wednesday, August 3, 2011 10:03


Following the recent press coverage (>> link to the article) of information on the non publication of a recommendation by the Office of Aviation Safety Investigations and Analysis, Solidarity & Mutual Aid Association 447 expresses strong dissatisfaction and extreme indignation at this travesty.

Indeed, despite a very short period of analysis of the third report of the BEA, we note that the concomitant loss of data of speed and impact generated a particularly critical situation, and this situation to date, has still not explained technically.

Thus, the absence of alarm stall (Stall) suggests the pilots that the situation is improving aerodynamics of the aircraft, when in fact it is getting worse.

Similarly, the occurrence of this alarm and respect as part of the procedure then in force, without viewing the possible impact, led the pilots to increase engine thrust (TO.GA) and consequently, further increase the incidence of the aircraft.

To this we must add the difference in procedure "IAS Doubtful" in relation to the maneuver called an emergency (Memory Items), indicating that of Air France to respect the alarm drop, while that Airbus does not specify .

Thus, considering that for obvious security reasons immediate action must be taken, we ask that a recommendation be issued by the BEA, for one hand, informing the drivers, and secondly, to adapt procedures to remarks above.
There is no need to wait for the outcome of a hypothetical group "human factors" to respond only to criteria of common sense.

It is also noteworthy that the recommendations of the official investigations are suffering from any lead time, which seems inconsistent with the concept of reactivity inherent to aviation safety.

In view of these events to the bias displayed, it is essential that the Association obtain a favorable response to his request through the courts to get all the data flight recorder.

Finally, we strongly condemn this sad episode that definitely casts discredit on the technical investigation and generates an unprecedented crisis of confidence towards the authorities investigated. The haste with which such authorities and officials have accused the pilots without any prior thought had alerted our suspicion. We now have confirmation that the statements issued by the authority of the BEA were not only premature, lacking objectivity, biased and very oriented toward the defense of Airbus.

This is totally improper and unacceptable. The victims of 447 do not deserve such an insult. Families of victims denounced a scandal, which violates their rights to truth ...

Association for Solidarity & Mutual AF 447
President
Robert Soulas

DozyWannabe
3rd Aug 2011, 14:07
Originally posted by "Dozy" With respect, all the sequence between 2:12-20 and 2:13-00 is a succession of nose down inputs followed by stall warning activations followed by nose up inputs (in reaction to the alarm ?).

Look closely:

2:12:28 - Stick *back* (between 8 and 16 degrees)

2:12:35 - Stick *forward* (16 degrees, this is the only correlation at a potentially recoverable altitude)

2:12:40-2:12:45 - Stick moves from *back* (between -4 and -8 degrees) at onset, through *neutral* to *forward* (The stall warning actually *stops* with the stick approx 4 degrees forward - correct behaviour!)

2:12:48-2:12:55 - Stick is *back* at onset (approx -12 degrees) and stall warning *stops* as stick moves from *neutral* to *forward* (approx 4 degrees), again apparently correct behaviour.

@ross_M : I'd recommend slogging through the threads to get yourself up to speed, but for reference, when airspeed becomes unreliable for more than a set period of time (25 seconds I think?) -> ADR DISAGREE mode -> ALTERNATE 2 LATCHED (which means Normal Law is out-of-bounds for the duration of the flight).

@jcj - spoken like a true weaselly lawyer, going for the deepest pockets. Airbus have already come in for criticism (and will be expected to share in the secondary causes at least) due to the pitot tube issues, and what the press are reporting as "blaming the pilots" is in fact explicit criticism of Air France and the industry in general. I think a new phrase should be coined for using the press to instill doubt in the public mind - "Doing an Asseline".

@RWA (below - sorry, don't want to spam the thread!) - It looks to me like they're just covering all bases, as according to the report, the A/P did indeed click off when ADR DISAGREE was detected, and Alternate 2 was indeed latched. It's possible that they discovered in the simulator testing that it was nevertheless possible to re-engage the A/P if the readings were similar but erroneous.

RWA
3rd Aug 2011, 14:16
Any of us who have been involved in 'accident investigations' of any kind will have experienced the way things tend to develop on a 'double track.' It's not usually possible to reveal the 'whole truth' all at once - particularly in cases like this, where so many issues remain unresolved. But the 'lower orders' - in government, among the manufacturers, and in the airlines - will always make every effort (though quietly) to reduce the likelihood of anything like this happening again.

In this connection I find this article interesting:-

"Europe's safety authority is to order Airbus A330 (http://www.flightglobal.com/landingpage/airbus%20a330.html) and A340 (http://www.flightglobal.com/landingpage/airbus%20a340.html) operators to upgrade flight-control computer software to prevent autopilot engagement should airspeeds become unreliable.

"Autopilot and auto-thrust on the types will automatically disconnect, and the aircraft will revert to alternate law, in cases where significant differences emerge between the airspeed sources.

"This condition can arise if, for example, the pitot system becomes contaminated with ice.

"Previously the European Aviation Safety Agency warned that, under such circumstances, it was possible for two airspeed sources to show similar - but nevertheless erroneous - data.

"This would permit the crew to re-engage the autopilot while the airspeed data was unsound, potentially resulting in the autopilot transmitting unexpected commands to the flight-control system - such as an abrupt pitch-up.

"EASA had cautioned pilots, in a December 2010 directive, to resist re-engaging the autopilot until they had carried out a cross-check of speed indications to ensure that the airspeed data was reliable.

"Since that directive was issued, new primary flight-control computer software has been developed which, EASA states, will "inhibit autopilot engagement under unreliable airspeed conditions"."

A330/340 change to inhibit autopilot if airspeed unreliable (http://www.flightglobal.com/articles/2011/08/02/360261/a330340-change-to-inhibit-autopilot-if-airspeed-unreliable.html)

As an additional contribution to the debate, a mate of mine with aviation connections (in Indonesia) just sent me this - which appears to be a first, unofficial, English translation of the AF447 FDR content combined with the CVR transcript. I can't vouch for its authenticity - except that, as far as my knowledge of French goes, the words seem largely to correspond with the French transcript already published. Only thing is, the link misbehaves - people may need to 'zoom in' to about 400% to be able to read the text:-

http://www.globalsim.web.id/publicservice/AF447/AF447TimelinePlotJuly2011v10.jpg

jcjeant
3rd Aug 2011, 14:33
Hi,

"EASA had cautioned pilots, in a December 2010 directive, to resist re-engaging the autopilot until they had carried out a cross-check of speed indications to ensure that the airspeed data was reliable.Is it possible to have a software program to carried out a cross-check of speed to ensure that the airspeed data was reliable ? instead a crosscheck from the pilots ?

If a software program is able to declare invalid airspeeds and warn the crew (and disengaging the AP) I suppose it's also possible to have the reverse (warn the crew of valid airspeeds and engage again the AP)

Logic ?

bearfoil
3rd Aug 2011, 15:00
jcjeant

Please read my post above.

I thank you for your perseverence, and your scepticism of BEA and the commercial principes.

The TRUTH is always in the middle. (Well almost always).

ap08
3rd Aug 2011, 15:03
http://www.globalsim.web.id/publicse...uly2011v10.jpg
Simmers site. Must be fake.

carlosgustavo
3rd Aug 2011, 15:18
LONEWOLF_50
I dont know if you are right about the sound of stall inside a stall. All Airbus says on the O. Manual is:
WHEN STALL WARNING STOPS PILOT MAY INCREASE BACK PRESS AGAIN IN ORTHER TO RECOVER TRAJECTORY.

I dont for you, but seems To me that if it works as you say Anywhere in the Operations Manual should be a Caution warning that at high AOA stall warning stops. BUT IT DOESNT.

Thanks for tour answer. Is good To learn from others and To share thoughts.

Good flights.

xcitation
3rd Aug 2011, 15:55
The real kicker, I suspect, is the timing of the captain's re-entry to the cockpit - almost exactly at the point where the continuous stall alarm switched off. I wonder what he would have done if he'd heard nearly a minute's worth of stall warning.

To that point the PNF did not brief CAP that the stall warning had been ringing for a minute.



The rest was history, as the situation required immediatre transfer of control to PNF, whose spatial orientation and understanding of the situation appears clearly superior throughout. No time for egalitarian social norms.
I think Takata and others suggested that PF was PIC so the left seat FO could not take over in such a manner. It has been suggested that he might have liked to based on wording and dual input. When CAP returned to FD there was little time/benefit for seat change.

ChristiaanJ
3rd Aug 2011, 16:24
I think Takata and others suggested that PF was PIC so the left seat FO could not take over in such a manner. It has been suggested that he might have liked to based on wording and dual input.
I think it's been described here before.... There is a button on the sidestick that - when held down for a given time - transfers control to that side stick.
The function is normally there to either transfer control, or in the case of PF incapacitation.
No need to change seats.

xcitation
3rd Aug 2011, 16:48
Christiaan

I know about overide button on SS.
However I also read that the FO in left seat lacked the authority, unless he declares FO in right seat incapable. Difficult in this situation as there was no obvious medical problem with PF. Il voudrait un coup d'état, non?

BOAC
3rd Aug 2011, 16:58
Out of interest, what happens in this 'computer game' if the one who has 'lost' control then presses the button for the requisite time?

Lonewolf_50
3rd Aug 2011, 17:57
JJFFC

2/ Don't forget that neither the PNF nor the Capt. ever knew that the PF made an initial huge nose up => how many of us could have imagine that ?
From CVR release, early in the event PNF was nagging PF to get his nose down, or to stop climbing.
Am I right in saying that on this type if inputs are made on both sidesticks the system will take the algebraic sum of those inputs?
In which case if one pilot was maintaining full and up and the other full down this would equal neutral - not what you need for stall recovery.

Back to "take the controls" if you have to come on to the controls ... CRM issue.
MountainBear:
I have held that
(1) the logic of the stall warning system is flawed
(2) that this accident illustrates the nature of those flaws
(3) that these flaws are one possible explanation for the pilots behavior doing one specific phase of the accident
(4) that the professionals who designed the system should be held accountable for those flaws to the extent they played any role in this accident.

Rational position to take. I'm on board with most of it.
Dozy:
I'd say the extreme AoA was probably fouling the static data from 02:11:47 onwards.
More likely fouling pitot data. Static doesn't tend to be in the airstream, unless they've changed that recently. You don't want to contaminate static air with dynamic pressure, do you? :confused:
When a french pilot said GAUCHISSEMENT he speak 's about ROLL
Merci, monsieur. :ok:
Three miles
If they felt they were fast and descending perhaps they thought this was a high speed stall warning? In which case relaxing the back stick but still mantaining some might make sense.
IMHO the ignorance {me - Ignoring?} of the audible stall warning could only be caused by the pilots assuming, that the stall warning would be triggered by too low speed (instead of AoA).
Speed incorrect -> Stall warning -> ignore it
When the speed came back they had stalled the plane and the speed stayed low => assumption: still incorrect.
Why should they believe now, that the speed was more correct than before?
Why should they believe with all this confusing stuff around them, that any other indication was more correct?
The speed even became lower and lower and the stall warning disappeared at some point. -> continue to ignore all this
Well said.
Kalium:
I wonder what he {captain} would have done if he'd heard nearly a minute's worth of stall warning.
Might have changed his SA, that.

Mimpe:
When the birds hit the 737 over Manhattan, pretty much the first action fronm Sullenberger was.." My Aircraft".
Good point, but Sully was the Captain. :) There was no role ambiguity for him. PNF had that to deal with.
...my concern is that PF may well have been more than just worried about overpeed. Its clear he had lost his initial crucial scan, was overcontrolling, and I feel as the aircraft slowed with zoom climb, may well have crossed the rubicon of lapsing into a sensory interpretation of what the aircraft was doing.
Possible. How often do AF train hand flying on instruments at high altitude? How comfortable was he in that scan and that task?
I feel the decleration he was experiencing in the late stages of the climb, heightened by marked anxiety, probably ended in a somatogravic illusion of acceleration, and persistent nose up inputs unto death ... situation required immediate transfer of control to PNF, whose spatial orientation and understanding of the situation appears clearly superior throughout. No time for egalitarian social norms.
Yes, early on. By the time the Captain got there, he confessed that he wasn't sure what was wrong. His SA hadn't quite deciphered the SW when it was correct. :(
GerardC
In all, 4 stall warning activations. Would not YOU be confused : nose down -> stall ; nose up -> NO stall.
Was this sort of thing ever practiced in the sim among A330 pilots? Among AF pilots?

This whole scenario reminds me how dependent we are on airspeed as a crosscheck for performance.
ross M:

About auto switching back to normal law protections. (That puts the robot into a struggle with the pilot for control deflection).

As I understand law changes, latching Alt 2 requires substantial effort to revert to normal law. Auto switch is probably not a good idea, from a design perspective, and for any pilot flying.

If you keep getting spurious inputs, auto re-engage would kick you back to Norm Law from Alt Law even if the problem didn't go away.

You could get stuck into the following cycle: Alt Law kick Norm kick Alt kick Norm kick Flicker -- talk about a pain to fly.

Imagine flying with the electric trim kicking on and off, intermittently. Eventually, you secure the trim so it stops doing that to you. (Yes, I've had trim weirdness like that in the dim and distant past. Ended up being a touch of hydraulic contamination. )

RWA: nicely said, thanks. So many good minds at work today! :)

carlosgustavo:
LONEWOLF_50. I dont know if you are right about the sound of stall inside a stall. All Airbus says on the O. Manual is: WHEN STALL WARNING STOPS PILOT MAY INCREASE BACK PRESS AGAIN IN ORTHER TO RECOVER TRAJECTORY.
I dont for you, but seems To me that if it works as you say Anywhere in the Operations Manual should be a Caution warning that at high AOA stall warning stops. BUT IT DOESNT.
Thanks for tour answer. Is good To learn from others and To share thoughts. Good flights.

The stall warning alpha looks (from my tech info) to trigger stall warning at a value of alpha less than stall alpha. That tells me you get the warning before you actually hit that critical alpha and stall.
Does that make sense to you? (I may be missing something). It makes sense to me.

For your kind words: Muchas gracias, carlos, y vaya con Dios. :)
To that point the PNF did not brief CAP that the stall warning had been ringing for a minute.
Aye, he seems to have filtered that noise out.

BOAC: Out of interest, what happens in this 'computer game' if the one who has 'lost' control then presses the button for the requisite time?
He gets to keep "flying," eh? :eek:

carlosgustavo
3rd Aug 2011, 18:05
Excellent link To the matrix of the accidente. Looks real To me.
They were more focus on bank than in pich.
Anybody else think of a SPIN induced by stall plus turbucence that they didnt recognice because of the IMC condicions?

DozyWannabe
3rd Aug 2011, 18:15
More likely fouling pitot data. Static doesn't tend to be in the airstream, unless they've changed that recently. You don't want to contaminate static air with dynamic pressure, do you? :confused:


I'm trying to make sense of the VSI trace after 2:11:45. Do those look like viable readings or is something messing with them? AFAIK VSI does not use pitot data as an input...

Lonewolf_50
3rd Aug 2011, 18:17
Dozy, your comment on AoA fouling VSI implies to me that you think AoA had an impact on what was being read/sensed in the static ports. (But if that isn't what you were thinking, sorry about that). We have had considerable discussion on high AoA causing some problems with pitot tubes and the pressure they are sensing.

I'd need to look at the trace on a screen that doesn't have issues with images. Not all of the ones posted here come through on this machine/system.

carlos:
Don't think there was a spin. I wandered off the reservation on that score some months ago, before the data had been analyzed and some of it released.

The BEA reconstruction of the descent indicates a single "turn" (over three or four minutes) that changed heading of AF447 about 270 degrees to the right.

That doesn't look like a spin, but more of a stall with some waffling and rolling going on, mostly to the right.

xcitation
3rd Aug 2011, 18:36
carlos: the reconstruction of the descent indicates a single "turn" (over three or four minutes) that changed heading of AF447 about 270 degrees to the right.

So, no, not a spin, but a stall with some waffling and rolling going on, mostly to the right.

+1
When I have rec flown in stormy weather in a light a/c I was forced down on a grass airfield. On landing I have been spun around 180 deg to wind once speed slows and wet. Very unsettling as a/c was still on runway. The a/c has lost force on its flying/control surfaces and then becomes a weather vane. With less force on AF447's flying and control surfaces the influence of wind/gusts is greater. Did AF447 right turn into the wind direction?

ross_M
3rd Aug 2011, 19:12
Any lawsuits already been filed? I smell lots ahead. Plenty of blame to pass around and all defendants have deep pockets. Air France, Thales and Airbus must already be scampering for their lawyer teams.

carlosgustavo
3rd Aug 2011, 19:20
You are probably right Wolf, 270 degrees turn is not much, but between
2.11.35z 2.12.15z they are stalling and turning right between 16 and 40 bank and the VSI gets its higher values, even unreliable. At that monent IDLE thrust is selected producing a pich down moment that stops the stall of the right wing stoping the rotation but mantaining the Stall.

Worse of all Wolf is that no investigation will solve this.

jcjeant
3rd Aug 2011, 19:40
Hi,

Any lawsuits already been filed? If you had return early from your travel to the Moon (the dark side of) ... or read the press you can know that two lawsuits are already filed in France
One against Airbus and one against Air France ....

Le Figaro - Flash Actu : Af447:familles veulent accs aux donnes (http://www.lefigaro.fr/flash-actu/2011/08/03/97001-20110803FILWWW00324-af447familles-veulent-acces-aux-donnees.php)

L'association Entraide et Solidarité AF447, qui représente les familles des victimes du crash du vol Air France Rio-Paris en juin 2009, tente d'obtenir des magistrats instructeurs l'accès à l'ensemble des données des enregistreurs de vol, a indiqué mercredi son avocat.

La juge Sylvie Zimmermann a cependant refusé en juillet cette requête, au motif que l'enquête technique du Bureau d'enquêtes et d'analyses (BEA) n'était pas terminée et l'association a fait appel de cette décision, a déclaré Me Alain Jakubowicz.
En tant que partie civile, Entraide et Solidarité AF447 peut consulter les pièces du dossier de l'instruction menée par les juges Sylvie Zimmermann et Yann Daurelle, une enquête dans laquelle Air France et Airbus sont mis en examen pour homicides involontaires.

"Le problème est que les données ne figurent pas au dossier. Tout le monde en parle, notamment au travers du BEA, mais nous n'y avons pas accès car la juge dit qu'elle ne les a pas", a déclaré Me Jakubowicz.
"Il y a cependant un déséquilibre puisque Air France y a accès au travers de l'enquête du BEA", a-t-il ajouté.

L'association, qui a plusieurs fois dénoncé la partialité des informations du BEA et leur orientation vers la faute de pilotage, a fait le 13 juillet une demande formelle pour avoir accès à l'ensemble des données. Mais Sylvie Zimmermann a rejeté cette requête dans une ordonnance rendue le 18, selon Me Jakubowicz.
Entraide et Solidarité AF447 a fait appel, mais aucune date n'a pour l'heure été fixée pour ce débat qui se déroulera devant la chambre de l'instruction.

Réagissant au fait que le BEA a retiré de son dernier rapport une recommandation concernant les alarmes de décrochage, Robert Soulas, président de l'association, a jugé mercredi dans un communiqué que "ce triste épisode jette définitivement le discrédit sur l'investigation technique" et "génère une crise de confiance sans précédent envers les autorités d'enquêtes".
La catastrophe avait fait 228 victimes. Dans son dernier rapport d'étape, le BEA a notamment mis en cause la formation et les réactions de l'équipage après le décrochage de l'avion.

Mutual Aid and Solidarity Association 447, which represents the families of the victims of the crash of Air France flight from Rio to Paris in June 2009, trying to get magistrates access to all the data flight recorder, said Wednesday's lawyer.

Judge Sylvie Zimmermann, however, refused this request in July on the grounds that the technical investigation of the Bureau of Investigation and Analysis (BEA) was not completed and the association has appealed the decision, said Mr. Alain Jakubowicz.
As a civil party, Solidarity and Mutual 447 may consult the documents of the investigation carried out by the judges Sylvie and Yann Zimmermann Daurelle, a survey in which Air France and Airbus are under investigation for manslaughter.

"The problem is that data are not included in the file. Everyone talks about it, particularly through the BEA, but we do not have access because the judge said she did not," said Mr. Jakubowicz .
"But there is an imbalance, since Air France has access through the investigation of BEA," he added.

The association, which has repeatedly denounced the BEA bias information and orientation error in piloting, July 13 made a formal request for access to all data. But Sylvie Zimmermann rejected that request in an order made on 18, according to Mr. Jakubowicz.
Mutual aid and solidarity called 447, but no date has so far been set for this debate to be held before the Board of Education.

Reacting to the fact that BEA has withdrawn its last report a recommendation on the stall warning, Robert Soulas, president of the association, said Wednesday in a statement that "this sad episode definitely throw discredit on the technical investigation" and "generates an unprecedented crisis of confidence towards the authorities investigated."
The disaster had caused 228 victims. In its latest progress report, including the BEA has challenged the training and the reactions of the crew after dropping out of the plane.

Lonewolf_50
3rd Aug 2011, 20:50
The disaster had caused 228 victims. In its latest progress report, including the BEA has challenged the training and the reactions of the crew after dropping out of the plane.
Gotta love Le Figaro :rolleyes: ... they start a rumor about pilots dropping out of the plane --, wait, what's this, skydiving at night in a thunderstorm over the open ocean? I know pilots are adrenaline junkies, but this is something else again! :E How the heck did they get back into the plane before it hit the water? :confused::p

Perhaps google translate is to blame for this? :E:oh:

SeenItAll
3rd Aug 2011, 21:19
To me the issue seems to be whether we want pilots to fly an aircraft by playing a computer game, or whether we want them to fly an aircraft according to the laws of physics.

It seems pretty clear that the AF pilots were doing the former rather than the latter. The basic difference between the two is that with the computer game, it is the computer's instructions and feedback that are your "law." The stall warning starts to sound, this means that the aircraft is approaching stall. Placate the computer by pulling nose up and the stall warning stops -- the computer responds by telling you that you are playing the game "correctly." Note that although these pilots were likely trained to understand that the computer game has other "rules," such as keep an appropriate speed and attitude, the computer states that the stall warning has priority over all these other rules -- so you don't address them until you've dealt with job #1, silencing the stall warning.

In contrast, flying the aircraft according to the laws of physics tells you that if you are in a severe nose-up attitude with less than 60 knots of airspeed at FL 370 (or even any two of these three conditions), you are in stall. These laws also tell you that in an A330 weighing over 400,000 lbs. with a maximum of 140,000 lbs. of thrust, you cannot climb out of a stall as you might with an F-22. While AB software engineers have done wonderous things with FBW, they have not repealed Sir Isaac Newton.

Now I don't know enough about A330 maneuverabilty to know whether once the stall was entered, it was recoverable, but shouldn't these guys have known that nose-up had no dynamic hope? Or were they just expecting that the FBW computer would find some deus ex machina way of extracting them from this dire situation?

In fairness, AB should certainly change its stall warning protocol to make more clear when it is inhibited because of unreliable airspeed. And I guess it may also be possible that the accelerations in the cockpit made it impossible for the pilots to gain any situational awareness. But the tapes seem to suggest a relatively nonviolent descent into the ocean. In the end, it all comes down to what you can rely on. These pilots relied totally on the computer, and were willing to suspend any belief in physical law.

grity
3rd Aug 2011, 21:34
hi jcj risc a look at side 44 of the 3. report there are the values around 2:10:10 with much more details shown the purple line not the blue......

jcjeant
3rd Aug 2011, 21:35
Hi,

Gotta love Le Figaro :rolleyes: ... they start a rumor about pilots dropping out of the plane --, wait, what's this, skydiving at night in a thunderstorm over the open ocean? I know pilots are adrenaline junkies, but this is something else again! http://images.ibsrv.net/ibsrv/res/src:www.pprune.org/get/images/smilies/evil.gif How the heck did they get back into the plane before it hit the water? http://images.ibsrv.net/ibsrv/res/src:www.pprune.org/get/images/smilies/confused.gifhttp://images.ibsrv.net/ibsrv/res/src:www.pprune.org/get/images/smilies/tongue.gif

Perhaps google translate is to blame for this? http://images.ibsrv.net/ibsrv/res/src:www.pprune.org/get/images/smilies/evil.gif:oh: Drop out is to be understand as STALL .. I'm sure you known that :ok:
Must be certainly better jokes in the BEA offices ..
Don't forget that NTSB and a Brazilian party are also members (maybe as observers ?? but ..) of the investigation team .....
I wonder how all those people different by culture and language are communicating ... :8

exeng
3rd Aug 2011, 22:16
Out of interest, what happens in this 'computer game' if the one who has 'lost' control then presses the button for the requisite time?

Well BOAC the one who had 'lost control' now regains control - simples really - I have control -no I have control - no really I have control etc etc.

About as sensible as if no overide is pressed an input by the same amount in the same direction doubles the input, or if in the opposite direction negates the original input. Remember Hamburg.

I flew with one of our colleagues back in LGW days on the 737 who twice in two trips on a xwind landing put aileron in the wrong way. Frightening yes - but at least I could see what was happening and correct it before the inevitable - don't think that would have been possible on any Airbii.

Still the bus does have some good points like terrain escape which in my opinion is better than any Boeing, 777 included.

DozyWannabe
3rd Aug 2011, 23:36
About as sensible as if no overide is pressed an input by the same amount in the same direction doubles the input, or if in the opposite direction negates the original input. Remember Hamburg.

Aye, but if used and co-ordinated correctly you can get double the roll rate, which could be useful in an escape maneouvre, or if you see your opposite number doing something that doesn't look right you can negate their input before taking control.

I flew with one of our colleagues back in LGW days on the 737 who twice in two trips on a xwind landing put aileron in the wrong way. Frightening yes - but at least I could see what was happening and correct it before the inevitable - don't think that would have been possible on any Airbii.

Well, you could *see* it happening on a FBW Airbus (you have an ADI in front of you after all), that's never been the problem - the complaint has always been about *tactile* feedback. The thing is that tactile feedback used to serve multiple purposes when controls were directly connected to flight surfaces - you could feel how the surfaces were responding, you could feel what the other pilot was doing and assist if necessary (indeed you could also put more welly behind the maneouvre). But in todays modern world of hydraulically-controlled surfaces with no manual reversion you're down to being able to feel the other guys inputs, plus whatever the q-feel system is telling you. In a lot of cases this is nothing to be sneezed at, but in some cases it can give a false impression of having an effect on the flightpath when in fact you are not. UA232 was an exemplary display of CRM and aircraft control, but one of the interesting factors was the captain and co-pilot forcing their yokes forward and to the left, long after it was obvious that it was having absolutely no effect.

Airbus's philosophy was based on the idea that when going by the book, only one pilot should be manipulating the flight controls at any one time *except for extraneous circumstances* in which they designed the sidesticks to act in the same manner as the yoke, but by summing the inputs algebraically rather than by respective force. Backdrive was considered and ruled out because it added extra weight and complexity (complexity being the main issue), as well as causing extra problems in the event of systems failure or maintenance errors (e.g a cross-wired sidestick on one side).

Still the bus does have some good points like terrain escape which in my opinion is better than any Boeing, 777 included.

As always, there are usually positives and negatives to any differences in design philosophy, and to say that one is objectively better than another in all aspects is not only foolish, but tiresome after a while. ;)

mm43
3rd Aug 2011, 23:45
BEA Interim Report No.3 (English) Released.

English Version (http://www.bea.aero/docspa/2009/f-cp090601e3.en/pdf/f-cp090601e3.en.pdf)

JJFFC
3rd Aug 2011, 23:58
Hello DozyWannebe,




What do you mean by:
"this is the only correlation" at 02:12:35 ?
"correct behavior" at 02:12:40 and 02:12:48 ?
I understand that the stall alarm stoped after "stick forward" ?

Thank you,

DozyWannabe
4th Aug 2011, 00:25
@JJFFC

Simple. AF's argument is that the stall warning sounded at the same time as the pilots fed in nose-down inputs (i.e the correct way to recover from a stall) on every occasion. They are using this to argue that the stall warning gave a false impression to the pilots that they were doing the wrong thing by putting the nose down.

By matching up the trace graphics to the best of my ability it appears that this is not the case. On one occasion, the stall warning comes on at around the same time PF puts in a nose down input, but after then there appears to be no match whatsoever, and in my opinion appears to be in response to the pitch angle of the aircraft (which is stalling and out of control) as opposed to any sidestick input. In fact, if I've lined things up correctly, it appears in a couple of cases that the stall warning stops as nose-down is input, which would reinforce the correct behaviour by the terms that AF are putting forward.

TioPablo
4th Aug 2011, 00:43
A protection to me means a limit, something is prevented that could conceivably cause a serious problemDear Bear, sorry for my late answer... Was busy with other things...
What I meant to say all the time with the faulty switch of state (imo), is that the "reminder" given by Direct Law to use manual trim could have given a hint to the pilots about their attitude... And therfor: act as a protection...
If you don´t have any indication about your speed... What is the best action?
TO/GA?
Well, I don´t think so...
For me would be IDLE and trim-out to best gliding speed (AoA). Then pay attention to the blaring show...
If that switch of state (Direct Law thus), would have helped the pilots or not is at this stage irrelevant (or not). I think everybody were very busy during this years trying to solve this event and I´m almost certain we all will do their best to improve whatever went wrong. And as I said before.. I hope pilot unions will be there to see that safety recommendations (as issued by BEA), are implemented in a very near future.

JJFFC
4th Aug 2011, 00:43
I believe that the stall warning has nothing to do with the mental problem of the PF : whatever the stall warning, the PF wanted to nose up and didn't understood why the PNF and the Capt asked him not to.

Abstract :

2 h 13 min 40
PF : But I’ve been at maxi nose-up for a while
Capt : No no no don’t climb
PNF : So go down


2 h 13 min 45
PNF : So give me the controls the controls to me
PF : Go ahead you have the controls we are still in TOGA eh

2 h 14 min 05 4,024 The pitch attitude is 14°.
Capt : Watch out you’re pitching up there
PNF : I’m pitching up?
PF : Well we need to we are at four thousand feet :ugh:

(My) Conclusion:

The Capt. didn't knew how much the PF was nosing up but knew he shouldh't have.

The PNF knew he had to nose down but his fear prevented him from a strong forward stick;

The PF has alway wanted to nose up except when asked by the PNF or the Captain not to do.

The actions of the PF have been unbelievable / misunderstood by PNF and the Captain.

Not only the PF has created the stall by a stupid nose up but he has commited "a crime" when at 02:11:39 he took the controll back from the PNF without annoucement and continued to nose up against PNF and Capt.

JJFFC
4th Aug 2011, 00:46
Thank you :

Your observation is of such an importance regarding the debate with JcJeant and in France that I prefered to have you repeted it.

CONF iture
4th Aug 2011, 01:40
Well, you could *see* it happening on a FBW Airbus (you have an ADI in front of you after all), that's never been the problem - the complaint has always been about *tactile* feedback.
No Dozy, the PROBLEM has always been to know IF and HOW your partner makes flight control inputs.

But what do you know about flying a multi crew aircraft after all ... ?
Do you only know about flying ?

Sorry, but just getting tired of hearing you talking as even a 30000 hours retired Captain with 25 years on FBW Airbus would not dare to.

Please, let others talk if you don't know, or at least, let room for healthy reserve or doubt in your talking.

grimmrad
4th Aug 2011, 01:42
Not a pilot or even from the industry but I think the issue is that the stall warning activates if the plane gets close to a stall and STOPS once it is in the stall. So, imagine middle of the night, bad weather, some weird faults, suddenly stall warning. As someone pointed out (by whatever reason if I hit quote I do not get the quoted text) nose down gave stall warning, in nose up it stopped - not because the stall situation is gone but quite the opposite. If that is not confusing under normal circumstances how would it be in their particular situation...?

DozyWannabe
4th Aug 2011, 01:51
@JJFFC : I'm not saying I'm right, but I'm saying that there is certainly room for debate. This wouldn't be the first time that interested parties have used the press to push their case while only providing the details that supprt their side of the story...

No Dozy, the PROBLEM has always been to know IF and HOW your partner makes flight control inputs.

But what do you know about flying a multi crew aircraft after all ... ?
Do you only know about flying ?

Sorry, but just getting tired of hearing you talking as even a 30000 hours retired Captain with 25 years on FBW Airbus would not dare to.

Please, let others talk if you don't know, or at least, let room for healthy reserve or doubt in your talking.

CONF, we've been *well* aware of your position on non-backdriven sidesticks versus interconnected and/or backdriven yokes for over half a decade. I'm not saying your opinion is without merit - it has plenty, in a theoretical sense. But there are thousands of Airbus FBW pilots around the word that do not consider it a problem - this is not about *my* opinion, this is about *theirs*.

Given that we've had at least one similar incident where having an interconnected yoke made no difference whatsoever to the outcome (Birgenair), surely you must therefore consider that the theory which supports your personal preference may not necessarily be the solution in all cases?

jcjeant
4th Aug 2011, 02:03
Hi,

But there are thousands of Airbus FBW pilots around the word that do not consider it a problem - this is not about *my* opinion, this is about *theirs*.And those who maybe had a problem with are no more there for give theirs opinion ... sad ...
Only people alive can give theirs opinions

Graybeard
4th Aug 2011, 02:41
DWGiven that we've had at least one similar incident where having an interconnected yoke made no difference whatsoever to the outcome (Birgenair), surely you must therefore consider that the theory which supports your personal preference may not necessarily be the solution in all cases? Birgenair was different, because the lower ranked FO knew what was happening, and was emotionally powerless to correct the Capt. . The FO could have overpowered Capt. by pushing harder on the yoke. Could he have done that with a joystick?

As for your argument that the 777 backdrive can fail: it's built to the same safety standards as the Cat IIIc autoland, i.e., 10 -(7?) probability of undetected failure.

DozyWannabe
4th Aug 2011, 02:44
...the stall warning comes on...and in my opinion appears to be in response to the pitch angle of the aircraft (which is stalling and out of control) as opposed to any sidestick input.

http://i1088.photobucket.com/albums/i331/turricaned/fdr-att-sw.png

2:10:12 - *bang*

2:11:55 - *bang*

2:12:08-10 - *bang*

2:12:28 - *bang*

2:12:33 - *bang*

2:12:40 - *bang

2:12:48 - *bang*

2:13:52 - *bang*

2:14:20 - *bang*

I rest my case.

Fox3WheresMyBanana
4th Aug 2011, 03:29
OK, after reading the English version:

1 None of the pilots are even looking at the attitude indications OR

2 The PF is ignoring the stall warner because of the unreliable speeds, and

3 The PF is flying the stall warning / unreliable airspeed procedures for the Take-Off/Go-Around phase of flight, i.e. aiming for 15 degrees Nose-Up attitude, not the high altitude procedure.

Look at the stick input and pitch attitude after 2:11:00. The PF is trying to maintain 15 degrees pitch attitude. He states "I'm in TOGA".

At only one point, before 2:11:00 when the PNF insists, does the PF consistently apply Nose-Down controls. After that I think it's clear he's convinced they have a high speed situation because of the buffet, and thus completely fails to spot the stall.

I think it's possible that the PNF does think they are stalled when the Stall warner sounds at 2:10:51. The power comes up and he warns the PF about lateral stick. But the PNF either doesn't realize or doesn't see a problem with the PF trying to maintain 15 degrees NU.

No emergency procedures are verbally identified. No drills are done. No cross-checks of Attitude, or anything else, are called.

I'm not flying Air France again.

Thoughts on this theory anyone?

xcitation
4th Aug 2011, 03:34
there is a noise on track 1 of the CVR, at about 2 h 10 min 55, which might be the impact of the microphone striking a wall, heard at a stable frequency.


If PF was not belted (as found in the recovery) then could his mic and therefore head have hit a wall! I know this is purely speculative but a surprise to read it.

xcitation
4th Aug 2011, 04:02
The PNF insisted 3 times for the PF to descend. Finally PF responds with confusion and finally appears to recognize he has climbed.


Watch your speed (PNF)
Watch your speed
Okay, okay okay I’m going back down (PF)
Stabilise
Yeah
Go back down
(no response recorded)
According to the three you’re going up so go back down
Okay
You’re at go back down
It’s going we’re going (back) down
I’ll put you in in A T T (*)…
We are in yeah we are in climb


IMHO the PF appears to not be aware of his own actions, was he in physiological shock/mentally impared?
I have to say that the informality of the response to the requests is startling. Perhaps something is lost in translation or culture? It's almost like the PF is getting irritated by the request to descend. It is incongruous with the gravity of the situation. It reminds me exactly of the response of a teenager when they are asked to clean their room!
No doubts, he is at the wrong flight level, stall warnings blaring so I would be looking for an immediate roger, descending back to FL350. Due to the gravity of the situation and after 3 failures to descend would it be reasonable to think PF is mentally impared/SS fail and take control?

jcjeant
4th Aug 2011, 04:08
Hi,

I have to say that the informality of the response to the requests is startling. Perhaps something is lost in translation No .. you have a good feeling
This conversation between pilots seem's a extract of a bad Hollywood catastrophe movie .... with Laurel and Hardy

xcitation
4th Aug 2011, 04:12
DW
are you saying that the nose ups did not cause the stall warning.
Are you trying to correlate stick inputs to warnings. Remember there is inertia to such a heavy close to max weight. This creates lags in response. The thin air at high altitude makes responses woolly compared with dense air close to the ground.

xcitation
4th Aug 2011, 05:04
OK, after reading the English version
1 None of the pilots are even looking at the attitude indications OR

IMHO PF was not reading the att ind due to physiological shock. I think the other 2 did see att ind.
The wings to flat horizon the standby horizon (CAP)
The horizon (second) (PNF)

2 The PF is ignoring the stall warner because of the unreliable speeds, andOk.

3 The PF is flying the stall warning / unreliable airspeed procedures for the Take-Off/Go-Around phase of flight, i.e. aiming for 15 degrees Nose-Up attitude, not the high altitude procedure.
Good call.

Look at the stick input and pitch attitude after 2:11:00. The PF is trying to maintain 15 degrees pitch attitude. He states "I'm in TOGA".
At only one point, before 2:11:00 when the PNF insists, does the PF consistently apply Nose-Down controls. After that I think it's clear he's convinced they have a high speed situation because of the buffet, and thus completely fails to spot the stall.

For me more curious is at the start AP disconnects and PF does aggressive stick back. Zoom climb begins. After 4 seconds the first brief stall warning occurs. It is largely ignored and they continue the climb to FL375. IMHO he PF was in shock and mentally impared by epinepherine surge.

I think it's possible that the PNF does think they are stalled when the Stall warner sounds at 2:10:51. The power comes up and he warns the PF about lateral stick. But the PNF either doesn't realize or doesn't see a problem with the PF trying to maintain 15 degrees NU
Agree.

No emergency procedures are verbally identified. No drills are done. No cross-checks of Attitude, or anything else, are called.Agree.

L-38
4th Aug 2011, 05:11
A very strong and convincing scenario, Fox 3! I have often had similar thoughts about Colgan Air 3407 (the Buffalo NY crash). Both pilots unexplainably maintained their aircraft in a stalled condition during nighttime adverse wx, with unfamiliar a/s indications.

Flying the stall warning / unreliable airspeed procedures for the Take-Off/Go-Around phase of flight in a simulator, was probably their most practiced of the unreliable airspeed procedures. . .something to revert to when one’s head is locked and “tunneled” in a similar, but very different situation.

This incident certainly dramatizes that verbally identifying emergency procedures, drills, and cross-checks of attitude, ect, is of the utmost importance of such cockpit discipline.

ankh
4th Aug 2011, 06:28
This aircraft was in a 'normal' not a high speed stall condition? (I'm wondering if the pilots could tell the difference, in the situation as they were experiencing it). http://www.pprune.org/flight-testing/373416-high-speed-stall.html

alainthailande
4th Aug 2011, 06:40
Just heard on the french radio Europe 1 that the pilot representatives announced that they quit the BEA workgroup due to profound disagreement with the (quote) biased inquiry (end quote). This comes, of course, after it became public that the recommendation for Airbus to revise the stall warning logic was removed from the 3rd interim report right before publication.

Mimpe
4th Aug 2011, 07:33
For all the various reasons above, an aggregated international body should do this investigation based on the raw data. I feel there is no confidence in the French investigation , especially amogst pilots and the travelling public. This is one of the most important crash investigations in history, and it requires clearly independant and fearless conclusions...no consideration AT ALL should be given to extraneous commercial factors .

Artificial horizon, altitude and derived groundspeed were all clearly available.The stall clearly warned and occured at the top of a zoom climb of at least 5000 fpm, leaving a persisting unacceptable nose up attitude clearly visible on the AH and a persistent initial stall warning. Airbus has to reprogram the stall parameters to any value that might reliably assist in extreme attitudes. I suppose a clearly visible AoA indication might have helped.

Fox, I pretty much agree with you...PF was impaired, but there is a toxic soup of design (stall programming parameters, non visible control inputs, digital verses analogue style readouts, etc ), Emergency response to aicraft upset and spatial disorientation, major CRM flaws, weather, possible unkown effects of other parties in the cockpit (unclear), the deleterious effects of automation technology on clear thinking problem solving at first principles level......even possible cultural traits affecting handover proceedures and flight discipline.

My favourite training adage was, " when things get really bad, take your own pulse first"

MountainBear
4th Aug 2011, 07:39
But there are thousands of Airbus FBW pilots around the word that do not consider it a problem - this is not about *my* opinion, this is about *theirs*On the Brittleness of Software « Dark Matter (http://msquair.wordpress.com/2011/07/23/requirements-completeness-and-the-af447-stall-warning/)

The point, DW, is that the knife cuts both ways. I won't denigrate either your efforts or your opinions. I will say that there are plenty of experts (both pilots and in academia) that disagree with your assessment of the stall warning system and the way it behaved in this particular situation. If you are going to insist that your battery of experts deserves respect then you must also give respect to the battery of experts that disagree with you.

airtren
4th Aug 2011, 07:39
@JJFFC

Simple. AF's argument is that the stall warning sounded at the same time as the pilots fed in nose-down inputs (i.e the correct way to recover from a stall) on every occasion. They are using this to argue that the stall warning gave a false impression to the pilots that they were doing the wrong thing by putting the nose down.

During the STALL, the Stall Warning was ON for 54 seconds, going OFF at FL350, after which it was OFF and ON, for various short durations 10 times during the rest of the "a/c" descent.

It has been explained on the Tech Log, and the BEA Interim Report is documenting that the STALL Warning has shown two problems.

1. It stopped during the Stall, giving the wrong indication that the Stall condition went away, when there was no action performed to take the "a/c" out of the STALL, but rather the opposite.

2. It started during the Stall, while the PF was in the process of applying actions to take the "a/c" off the STALL, with ND commands, giving the wrong message that the "a/c" enters a STALL.

These two problems contributed to the confusion in the cockpit, during the Phase 3, after the STALL.


By matching up the trace graphics to the best of my ability it appears that this is not the case.
On one occasion, the stall warning comes on at around the same time PF puts in a nose down input, but after then there appears to be no match whatsoever, and in my opinion appears to be in response to the pitch angle of the aircraft (which is stalling and out of control) as opposed to any sidestick input. In fact, if I've lined things up correctly, it appears in a couple of cases that the stall warning stops as nose-down is input, which would reinforce the correct behaviour by the terms that AF are putting forward.
I've seen the graph that you've posted on the Tech Log, and the one on this thread. The one I've seen on the Tech Log the Stall Warning graph was not aligned well, it was pasted towards the left, and thus there was misalignment of the vertical axe (Y) with the PF and PNF stick graphs.
I've commented on the misalignment, but am not sure if you edited it, and re-post.

The BEA report states the correlation, as it was explained it above.

The graphs - this has been mentioned on the Tech Log - that out that the 8 Stall Warnings, 6 are aligned with time intervals with ND commands, and 2 with time intervals with less NU and ND commands The PF stick command graph has not enough resolution to see clearly that the remaining 2 Stall Warnings coincide with NU spikes.

I have no idea why any of the above would be attributed to AF.

alenka
4th Aug 2011, 07:44
Third interim report, 29 July 2011 (http://www.bea.aero/docspa/2009/f-cp090601e3.en/pdf/f-cp090601e3.en.pdf) (published in English on 4 August 2011)

http://www.bea.aero/docspa/2009/f-cp090601e3.en/pdf/f-cp090601e3.en.pdf

airtren
4th Aug 2011, 07:52
I have not followed the Stall Warning discussion on this thread earlier, so I apologies for my delayed questions:.

It looks like the STALL Warning OFF, coincides with Pitch NU increase, while STALL Warning ON, coincides with Pitch ND decrease.

What caused the pitch attitude variations?


http://i1088.photobucket.com/albums/i331/turricaned/fdr-att-sw.png

2:10:12 - *bang*

2:11:55 - *bang*

2:12:08-10 - *bang*

2:12:28 - *bang*

2:12:33 - *bang*

2:12:40 - *bang

2:12:48 - *bang*

2:13:52 - *bang*

2:14:20 - *bang*

I rest my case.

airtren
4th Aug 2011, 08:17
I concur with the thought that knowing the sharing the information about the stick actions in the cockpit is a good thing. In the AF 447 case, it would have allowed the PNF know exactly what the PF was doing, in Phase 2, and Phase 3, which were both critical.

A 3D animation of the stick, shown on a screen could be one way to do it.

No Dozy, the PROBLEM has always been to know IF and HOW your partner makes flight control inputs.

DozyWannabe
4th Aug 2011, 09:22
DW
are you saying that the nose ups did not cause the stall warning.
Are you trying to correlate stick inputs to warnings.

I'm trying to say that the stall warnings do not coincide with inputs, but with the attitude of the aircraft (which did not always correspond with inputs due to it's stalled state).

It looks like the STALL Warning OFF, coincides with Pitch NU increase, while STALL Warning ON, coincides with Pitch ND decrease.

Really? To me it looks like (after the stall) the Stall Warning comes on as the nose begins to pitch back up, then switches off as the pitch-up causes the aircraft to assume an extreme AoA and slow down again. Then the nose comes down again, a little speed is picked up and the stall warning comes back on as the nose starts to come up.

What caused the pitch attitude variations?

Aerodynamic forces present in the stall, in combination with the position of the flight control surfaces at the time. If you've ever made a paper aeroplane and thrown it while pitched nose-up, you'll remember that the nose went up, the paper aeroplane stalled due to the high angle, the nose came back down and usually it made a change in direction of some kind as it fell to the ground.


Either way the path was not always under the control of the pilots, so my view is that while the stall warning logic is unsatisfactory in this extreme circumstance, I believe that if the stall warning did contradict or reinforce pilot behaviour, it was a coincidence rather than a consequence (note the nose going down several times while the PF's SS is back at the stops)

Fox3WheresMyBanana
4th Aug 2011, 11:37
I have some experience lecturing on FBW flight controls, and instructing in a simulator. Aircrew tend to follow A drill, rather than do nothing. The usual reasons for following the wrong drill are rushing into action based on only one or two bits of information (probably the audio warning and the speed readout failure in this case), reverting to type (flying the aircraft/action they are most familiar with, e.g. TOGA loss of IAS), and forgetting the nasty little corners of the aircrew manual (no stall warner below 60kts in this case).
All three reasons for doing the wrong thing are present here.

I've also been hit by lightning IMC in the dark at 30-odd k and lost instrumentation/aircraft systems/AP. It's very disorientating, as would all the loud noises be to them. Add the bumps and you have no physical sense of what the aircraft is doing. Very easy not to recognise the stall in this situation. PNF should be cross-checking and isn't.


Power, Attitude, Trim.

The PF is flying for 15 degrees NU, power is variable as he's not sure of speed. There's no trimming, probably because he's forgotten it.

In fact, I think he's going for at least 12 degrees Nose-Up attitude right from the start of the problem.

Question please, doesn't everybody memorise the Power/Attitude combinations for t/o, climbout, cruise, descent and approach any more?

This situation should have been met with.
Take control
Set 2.5 degrees nose-up attitude and 90% power.
Cancel warnings, identify loss of IAS readouts.
Get PNF to confirm diagnosis.
Run through drills.
Recall Captain to flight deck.

What it's met with is:
Take control
Fly unreliable IAS drill calling for 12/15 degrees nose-up attitude
Push power up when stall warner sounds (instinctive)
No correct communication with PNF

I do think the Captain's failure to formally divide the tasks before leaving the cockpit is important to the last point.

RWA
4th Aug 2011, 11:45
I think maybe most of us are being a bit 'unfair' to the pilots. The FDR/CVR confirms that, for just about all of the time, they didn't have speeds - and both the Flight Directors kept cutting out at intervals, so very probably they didn't have working artificial horizons either for long periods. Indeed, late on, the Captain told the PF to use the ISIS, the standby instruments - that's clear proof, to my mind, that they literally couldn't see 'which way was up' (or, very sadly, which way was DOWN) from the normal displays.

Another thing that bugs me a bit is that the 3rd. report confirms without qualification that the THS, as reported earlier, went to virtually 'full up' at the outset and stayed there for good. Despite the fact that there were nosedown inputs at intervals. It ALSO confirms that in Alternate Law autotrim remains in operation.

Been thinking a bit about trim. In the stuff I flew (mostly gliders) it was an 'aid' only - it didn't 'think.' Generally speaking, if you wanted a sustained climb or descent, you moved the stick and then adjusted the trim until the stick forces were 'neutral' - when you wanted to level out you did the same thing over again. Point was, the trim was the servant, not the master.

The autotrim in Airbuses (maybe Boeings as well, for all I know) appears nowadays to go ON adding trim (up or down) after an up or down command unless and until the pilot makes an 'equal and opposite' movement of the stick. I just don't think that's sensible or necessary.

Another factor is Airbus's practice of not providing sidestick feedback. As indicated above, I simply don't know how anyone could fly effectively (not 'seat of the pants' stuff anyway) without it; seems to me that Airbus pilots (Boeing still provide feedback, albeit artificial) are permanently 'flying IFR' at present.

Yet another thing is the sidestick idea in itself. It virtually guarantees that neither pilot (plus the captain in this case) can see what inputs the other guy is actually making; they have somehow to work it out, after the event, from what the instruments show (IFR again). Monitoring what the other guy is actually doing is no problem with the traditional yoke or 'stick between the knees.'

Very much hope that Airbus review their whole 'design philosophy' about sticks etc. (especially the 'feedback' issue) as a result of this accident (plus others, like the Perpignan one). I believe that the spring-loaded, 'no feedback' sidestick was originally introduced purely as a weight-saving measure. Might be a good idea to reconsider that decision, even if it does mean a few extra pounds of weight?

JJFFC
4th Aug 2011, 11:48
Apart from technical issues, let's deal with the psychology and procedures:

- Should the captain have leave his seat to an adolescent yet he had a bad feeling ("Do you "really" have your licence ?"), furthermore in front of his girl friend ?

- Does it exists a procedure that the Capt. didn't followed that would have prevented him from leaving his seat to an adolescent ?:{

- Does it exists a procedure that could have allowed the PNF to take control by strengh after the PF has re-taken control without annoucement yet the PF had admitted having lost the plane ?:ugh:

- Is there a procedure that would have allowed the Captain, when entering the cockpit, to understand that the problem was dealing with the PF mental attitude ?:confused:

- Is there a procedure that would have imposed him to discharged the PF and take control or give control to the PF ?:confused:

Thank you

amos2
4th Aug 2011, 12:15
1. no
2. no
3. no
4. no
5. no

Neptunus Rex
4th Aug 2011, 12:21
JJFFC

Yes, there is a 'procedure.' It is called Airmanship.

grimmrad
4th Aug 2011, 12:28
What also strikes me is that at no time someone mentions they are going down i.e. going to crash. They state arriving at 100 but no where do I see a human reaction like "oh my god we are going to..." or something alike. Did they not realize it? Probably good for them but maybe not good for their plan of action (survival mode)?

GerardC
4th Aug 2011, 12:30
But there are thousands of Airbus FBW pilots around the word that do not consider it a problem - this is not about *my* opinion, this is about *theirs*.Yes Dozy, but there are thousands of pilots around the world that have NO other choice than flying yoke-less a/c.

I recently had a chat with a free-lance captain with both A320 and B 737 ratings.
He told me "when all is OK Airbus is better. In crosswind, windshear, if something goes wrong etc... B is better".

It is clear from cockpit dialogue that neither PNF or Captain (when back) had any idea of what the PF was doing with his SS.

You cannot dismiss this is a true problem.

DozyWannabe
4th Aug 2011, 12:33
...both the Flight Directors kept cutting out at intervals, so very probably they didn't have working artificial horizons either for long periods.

The Flight Director is a digital overlay on the ADI - non-presence of FD does *not* indicate that the AH component is not working.


Indeed, late on, the Captain told the PF to use the ISIS, the standby instruments - that's clear proof, to my mind, that they literally couldn't see 'which way was up' (or, very sadly, which way was DOWN) from the normal displays.

He says "Horizon - Standby Horizon", which could just as easily indicate that the two are in agreement and he is drawing their attention to that fact.

I believe that the spring-loaded, 'no feedback' sidestick was originally introduced purely as a weight-saving measure.

Not at all.

Monitoring what the other guy is actually doing is no problem with the traditional yoke or 'stick between the knees.'

Knocking the A/P out by bumping and getting foreign objects jammed in the traditional yoke or "stick between the knees" have caused accidents in the past too - it's not all one-sided.

Very much hope that Airbus review their whole 'design philosophy' about sticks etc. (especially the 'feedback' issue) as a result of this accident (plus others, like the Perpignan one). Might be a good idea to reconsider that decision, even if it does mean a few extra pounds of weight?

Of course, why not just throw away years of development and just make planes the Boeing way to satisfy a minority of pilots who can't deal with having the training wheels off? Yeesh...

@GerardC - that's fine but it's only one pilot's opinion. There are a fair number on this very forum who don't see the lack of backdrive as a problem because they have other methods that compensate for it. Also, as I've said more times than I care to recall, the A320 flight deck and controls layout didn't stop Sully!

Fox3WheresMyBanana
4th Aug 2011, 12:38
Without wishing to sound facetious, couldn't the PNF have asked the PF what he was doing?

I would have thought it's his job to.:ugh:

Not doing so certainly turned out to be more than his life was worth.

martinhauptman007
4th Aug 2011, 12:49
Here is what an A330 captain said about the crash:

The key ingredient most everyone seems to be overlooking: The flight control laws of an Airbus. An Airbus has flight envelope protections that cannot be overridden by the pilot. This is almost always a good thing because the airplane won’t allow the pilot to overspeed, stall, overbank or overload the airplane. In the peculiar case of [Air France Flight] 447, the airspeed reading was inaccurate because the pitot tubes were blocked — a very rare occurrence in a jet — almost never happens.

But when it does happen, the airspeed then acts like an altimeter: When the airplane climbs, the indicated airspeed increases, and when the airplane descends, the indicated airspeed decreases. My best guess for AF447 is that the airplane was climbing, most likely due to turbulence; I believe they were in a thunderstorm. From a pilot’s perspective, this is a bad place to be. It’s rough and difficult to read instruments. Autopilot disengages due to turbulence or ice on the airframe or pitot tubes. The airplane is climbing, and the pilot is wondering what the **** is going on. Then, as the airplane climbs, with the false readings still indicating increased airspeed, at high altitude the margin between cruise airspeed and overspeed becomes very small, so the airplane overspeeds — or so it “thinks,” due to the false reading. And it’s at this point, provided all of this is what really happened, that they’re ******.


Think back to the Airbus flight envelope protections I mentioned, and the fact that the pilot can’t override them. The airplane computers “think” the aircraft is overspeeding and therefore continue to increase the airplane’s angle of attack. That only makes it climb steeper, thus perpetuating this cycle of increasing indicated airspeed and increasing angle of attack. This continues until the airplane is at a ridiculously high nose-up attitude and stalls, regardless of pilot inputs.

This is why we really need to wait for a full analysis, so that investigators can figure out what the pilot inputs were and whether or not they were consistent with what the flight control surfaces were doing. In other words, were the pilots ******* up the control deflections, or were the Airbus flight computers ******* up the control deflections? Because the airplane eventually stalled, I can only surmise that it was the computers ******* up, because when the computers do their jobs correctly, they increase angle of attack in this situation — again, regardless of pilot input.

So the airplane stalled. One plausible theory is what I just described. (There are other scenarios in which the flight control laws are degraded and the airplane can stall under certain circumstances, but that’s a whole other set of seriously complex stuff. Who knows though? Maybe that’s actually what happened.) Even if this guess doesn’t explain precisely what took place, it constitutes a design flaw in the Airbus that needs to be fixed in that the flight envelope protections need to be disabled if they’re receiving inaccurate information.

Source:An Airbus Captain s Take on the Air France Disaster (http://www.tourismandaviation.com/news-11106--An_Airbus_Captain_s_Take_on_the_Air_France_Disaster)

Victor2
4th Aug 2011, 13:10
A bit late in the day but thought that I would make an observation!

Apparently neither pilot was trained in high altitude flight. If that was the case they would not have practiced stall recovery in that regime. Neither is is logical that when pilots spend 60+% of their flying in this environment such an omission is tolerated.

Safety in aviation is usually calculated reference to the risk ratio of 1 in 10 to the -6 or 10 to the -7 depending on the critical nature of the system under consideration. The reliability of the airspeed sensors would come into this consideration i.e. the likelihood of failure is extremely remote. This all changes when such an event occurs. This was apparently the case with the A300 where such previous failures had occurred and a "fix" was in the pipeline.

While it would not be reasonable to stop all operations while "the fix" was being manufactured and incorporated, it would be more than reasonable to join the dots and realise that the reduction in risk should be ameliorated. In this case by highlighting the situation to the crews and by providing additional training to recognise and deal with the problem itself and the possible outcomes. In my view this is not "the benefit of hindsight" it is what management of safety and risk is all about.

DozyWannabe
4th Aug 2011, 13:26
@martinhauptman007 - Unfortunately the aircraft was neither in an autoflight regime, nor did it have active hard protections (due to Alternate 2 Law caused by the blocked pitot tubes). So that article is misinformed.

RWA
4th Aug 2011, 13:46
Quoting Dozywannabe:-

"Of course, why not just throw away years of development and just make planes the Boeing way to satisfy a minority of pilots who can't deal with having the training wheels off? Yeesh..."

Fair enough in its way, Dozy, mate.

But looking at it another way, for a bit longer than aeroplanes have been around, bicycles have. It would be perfectly possible, with today's 'electronic aids,' to design a bicycle that didn't need handlebars; so that the rider could turn just by 'body lean,' with his/her hands in their pockets....:)

But no-one has yet designed a bicycle that works that way. I'd venture to say, because yer av'rage rider would get a bit confused......

So precisely WHY, in your opinion, did Airbus opt for 'no feel/no feedback' etc.? A revolutionary change, after the best part of a century of producing aeroplanes that all 'worked' the same way?

My own view is that it was a matter of 'less weight/lower cost.' I can't think of any other reason?

Maybe you can?

bearfoil
4th Aug 2011, 13:55
xcitation. Way too early for this, I warn. In the desription of fox3banana I see a Pilot (if description is accurate), displaying some troubling issues.

First, there is a friction in the PF/PNF dynamic. PNF has taken role of leader.

Second, PF appears unwilling to admit mistake, and "insists" on taking control.

He appears to act without "executive function", internally.

Oppositional, lack of executive thinking, and poor impulse control.

This is admittedly unsupported, and I apologize for even bringing this to the front. However, the investigation might seem to be heading into a Human Factors/Dysfunction moment.

Understand that the situation is incredibly challenging. I have experienced panic while flying in wind shear, and it took all the energy I had to properly focus. These guys had one hurdle after the next, and many all at once. Each person can revert to less than effective performance when in this sort of challenge. That is why the sterile cockpit, Alcohol rules, and distractions are taken so seriously.

Astronauts (Used to) undergo extreme Physchological evaluation; some of the testing was barbaric.

No authority can loosen these rules for those entrusted to transport People by Air. We cannot let a loosening of flight chsallenges to degrade stress/performance requirements.

No criticism intended, and it may be only that this Pilot did not bring his "A" game to this flight. That is as far (and as lenient) as the situation can allow, for the sake of safety.


RWA Have you ridden a SEGWAY scooter? Two wheels, the handlebars are to support only your arms, and it turns by the cg change of your body.

It's been around for many years.

Also. FBW. It is early, but the HUMAN BRAIN has been shown to change tune a radio by wirelessly comanding the change by "thinking". I kid you not. "Mind command" is not far off. With the fine tuning of the kit now working, it is conceivable a pilot may fly without touching anything! It also warns to be very very cautious of distraction?

AIRBUS. RWA, don't leave out another motive for a "change" in flight controls. Complexity for the sake of marketing. NEW!! DIFFERENT!! CHEAPER!! and did we say NEW!!

airtren
4th Aug 2011, 14:32
Thanks again for posting the graphs.

If one plugs in the Stick and Thrust graphs as well, one will see that on the Pitch graph the Pitch Nose Down, and Stall Warning OFF/ON/OFF corresponds to either Thrust action - reduce Thurst - or Stick action ND, or both. Thrust and Stick variations after the A/THR disconnect are both PF/NPF actions.

http://farm7.static.flickr.com/6139/6011276723_794400eb0a_b.jpg

This brings Pilot action (thrust and stick) into correlation with all 10 OFF/ON/OFF Stall Warnings that occurred bellow FL350.

Regarding the interpretation of "coincidence" rather "consequence", it may be suffice to wonder if it really makes a difference, as the result was the same, one way or another: an addition to the other factor(s) of confusion.

While the reasons of the limitations are understood, with a systems engineering hat on, a behavior similar to the Stall Warning, would be ennoying if one had it on his car, or computer, or TV, or some other appliance, etc.... and would want it fixed. And sadly, one certainly would not want to have a chance to have it at all, in a "Hospital Surgery Room" or an airplane cockpit, in a critical life or death situation. (sad):sad:





I'm trying to say that the stall warnings do not coincide with inputs, but with the attitude of the aircraft (which did not always correspond with inputs due to it's stalled state).

Really? To me it looks like (after the stall) the Stall Warning comes on as the nose begins to pitch back up, then switches off as the pitch-up causes the aircraft to assume an extreme AoA and slow down again. Then the nose comes down again, a little speed is picked up and the stall warning comes back on as the nose starts to come up.
....
Either way the path was not always under the control of the pilots, so my view is that while the stall warning logic is unsatisfactory in this extreme circumstance, I believe that if the stall warning did contradict or reinforce pilot behaviour, it was a coincidence rather than a consequence (note the nose going down several times while the PF's SS is back at the stops)

CONF iture
4th Aug 2011, 14:38
But there are thousands of Airbus FBW pilots around the word that do not consider it a problem - this is not about *my* opinion, this is about *theirs*.

... surely you must therefore consider that the theory which supports your personal preference may not necessarily be the solution in all cases?
Let them have their own voice then ... In this AF447 time, not too many Ziegler on the board I must say.
Never seen it as THE solution - Just a waste of a very valuable source of information.

Also, as I've said more times than I care to recall, the A320 flight deck and controls layout didn't stop Sully!
What's your point here ?
Don't mix everything.


The bare minimum I would expect to read in the findings (and I'm not even talking about recommendations) :

The sidestick ergonomy as implemented by Airbus deprieved both PNF to actually realize what control inputs were applied by the PF.


But BEA is absolutely unable to formulate anything in that direction.

BOAC
4th Aug 2011, 14:44
Also for @martinhauptman007's 'Captain' - I see no evidence that the FDR thought there was an overspeed.

predictorM9
4th Aug 2011, 15:01
I don't think that the airbus design philosophy of a sidestick without feedback has caused the accident. Also, how do you generate the feedback when the speed data is lost? You can synthetize something based on the AOA vane sensor, but the fact that there was icing in this case precisely meant that all data was suspect. IMHO generating a feedback based on faulty sensors is even worse than no feedback at all.

But that doesn't remove the fact that the stall alarm design is completely unnatural and misleading, which is a big design flaw.

JJFFC
4th Aug 2011, 15:40
Considering :

2:11:37 : PNF takes controll after the PF having said 'I have lost the plane"

2:11:39 : PF re takes control from the PNF witout annoucement

2:11:42Captain enters

2:11:45 : End of CONTINUOUS stall

So the capt could believe the PF has save the plane but from 2:11:39 the PF is no longer a professional pilot.:ugh:

In an army, had he survived, he proubably would have go to the martial court for insoumission.

Before 2:11:39, the PF was a bad pilot. From 2:11:39, he could well be judged as a criminal...

xcitation
4th Aug 2011, 16:10
@JJFFC

I understand your emotional response to this very tragic incident. However I think we all owe it to the pilots to give them the benefit of the doubt. They did behave professional considering their level of training, experience etc.
Remember PF was confronted with a situation that he was not trained for i.e. UAS at high altitude. Throw in IMC and ITCZ and you have a nightmare. Clearly there was some mitigating circumstances and we only have a subset of the data. To their credit at no point did the 3 pilots give up trying. They fought for control down to the last second. For that they should be commended and we owe them the same professionalism.

SeenItAll
4th Aug 2011, 16:52
PF was confronted with a situation that he was not trained for i.e. UAS at high altitude.

I think this is too charitable. The one thing that we know they knew is that they were descending very rapidly. Aerodynamically, there are two ways for this to be the case: (a) they were in a deep (and fast) head-first dive; or (b) they were in a full tail-first stall. [Note, I am excluding the situation of the plane being fully laid over on its side.] Is it possible that things were so upset in the cockpit that over the course of three minutes in this attitude they were unable to discern the 60+ degrees of pitch difference between (a) and (b) -- and to remain convinced that it could only be (a)? I guess "yes," because the computer game stall warning was "god," aerodynamics be damned.

JJFFC
4th Aug 2011, 16:54
I apologize for this emotional response and I wasn't in that plane.

My point is about the PF' action :

2:11:39 : PF re takes control from the PNF witout annoucement

This is not a mistake, a lack of training it is a fault regardless the point of view, the country, the period in the history.

From Julius Caesar it is a fault..

bearfoil
4th Aug 2011, 17:30
SeenItAll

Don't forget the Lateral. Put together, it was a hell of a ride. Oh, and strictly speaking, it wasn't a "tail first STALL"?

nikplane
4th Aug 2011, 17:31
Hi, I see it this way:

The aircraft type fly-by-ware, in the cockpit there should be 2 emergence switches placed in standby instruments area (horizon-indicator,speed indicator-altitude indicator, also their systems must be totally separate from the other system, also add and mounting 4 ° pitot tube and 4°static port)

In the unusual emergency phase of putting on 1 switch must be activated on the system of flight controls direct with protection dumping elevator and rudder, but at the same time it must overraide all computer law: the normal law, alternate law , direct law, etc..
On news airplanes fly-by-ware, in the unusual emergency, last action must be only the pilots and not the law of computer. The computers works very goodin normal operations, but they’re stupid when in terrible Cb.

I'm Sorry, I Not well writing English language.

xcitation
4th Aug 2011, 17:54
I think this is too charitable. The one thing that we know they knew is that they were descending very rapidly. Aerodynamically, there are two ways for this to be the case: (a) they were in a deep (and fast) head-first dive; or (b) they were in a full tail-first stall. [Note, I am excluding the situation of the plane being fully laid over on its side.] Is it possible that things were so upset in the cockpit that over the course of three minutes in this attitude they were unable to discern the 60+ degrees of pitch difference between (a) and (b) -- and to remain convinced that it could only be (a)? I guess "yes," because the computer game stall warning was "god," aerodynamics be damned.
Except we do not have all the facts, nor lives on the line. How do you eliminate any margin of doubt and come to blame pilots. Even if they would have correctly identified a stall how would they recover. It is not a fighter, it was a fully loaded transport a/c. I read somewhere that they had 40 secs to correctly identify stall and begin recovery. Even then recovery could fail. Not a big time window given the confusing circumstances. 80% piltots have opposite/wrong reflex to stall warning. He was young and inexperienced, perhaps he was not in your 20%. This was all dumped on him by a long list of errors (training, experience, CRM, ALT law, software design, pitot fail, policy, accountants, weather...). Yes he made the wrong call. IMHO the question should be why not who.

Rob21
4th Aug 2011, 18:30
Unfortunately, when a pilot becames proficient in instrument flying and his reflexes on bringing back pitch and roll are sharp, then he goes to airline piloting. It is SOP to takeoff and in less than 5 minutes turn on the AP.

I wonder how many hands on (on type) flight time an experienced pilot (say, 5.000 hours) has.

I wonder if nowadays an airline pilot is able to hand fly his Airbus or Boeing from takeoff to FL 370 and hold it there for one hour smoothly, without sweating.

I can almost bet that this is prohibited by Ops Manual, or Regs.

All those sharp reflexes are long gone, and learn to hand fly smoothly only in an emergency, in only three minutes, how this is possible?

IMHO, in long duration flights, pilots should hand fly for at least one hour. And this would mean only 10% on the flight.

What is the percentage of hands on flying, nowadays, on a 10 hour flight?
One percent, maybe?

Many here will remember how difficult it was to believe the instruments on the beginning of IFR training, on real IMC conditions.

And, IMHO, the only way to stay proficient in IMC is flying with no AP. Flight SIM is kind'a OK, but how many SIM flight time an airline pilot gets in a month?

I think these pilots (AF 447) were good pilots, but they were victims of the system.

Victor2
4th Aug 2011, 18:57
For Bearfoil and Rob2:

I have studied in minute detail hundreds and hundreds of DFDR readouts/data in the study of events of various types where the F/O was PF. In many of them there were instances where it was obvious that the captain should have intervened earlier yet he did not. This where the command structure is self evident. Now we had the case where 2 F/Os were flying together. It is not surprising that there was indecision when it came to such a need for intervention. There is a very strong case for mandating that the senior (and one hopes more experienced and competent) always assumes the role of PF when the captain is absent from the flight deck. Thus this CRM issue is avoided.

As for manual flying, it is worth bearing in mind that when flying in RVSM airspace there is a requirement for the a/c to have a serviceable autopilot. Should the autopilot fail ATC must be informed and the a/c leave the designated air space. The inference is clear that manual flight is not permitted. We may not like it and the downside is obvious but we are where we are!

deSitter
4th Aug 2011, 19:00
Is is not possible to rescue an unused DC-10 or DC-8 from the boneyard in Arizona, and fly it around Hudson Bay, say, with a retinue of trainees in the back, taking their turns manual flying? It is unbelievable to me that manual flying is not one of the utmost priorities in professional piloting. Most people rationally assume that professional pilots are good at flying.

JCviggen
4th Aug 2011, 19:00
I think these pilots (AF 447) were good pilots, but they were victims of the system. Depends, I would say qualities such as keeping a calm head in an emergency, prioritizing and keeping things simple are necessary for any good pilot.
How it looks now I'm not sure they all had those traits.

It seems to me a set of extraordinary circumstances happened to coincide and the PF was the worst possible out of the 3 who it could happen to (thats how it looks to me anyway)

bearfoil
4th Aug 2011, 19:07
Victor, I am not trackin. The senior F/O was Flying. Not clear why it is in any way beneficial that a "CRM issue be avoided"?

So, by experience do you mean Time on Type? Or flying experience?

Colgan shows us a Captain with more flight hours than F/O but with substantially fewer ToT. Since it is believed he may have been recovering from a STALL other than mainplane (by mistake), perhaps she (FO) was better qualified to handle his emergency? (Self inflicted?) :confused:

Neptunus Rex
4th Aug 2011, 19:14
Rob 21

Good points. I have long maintained that the lack of hand flying should be ameliorated by a generous increase in Flight Simulator training. One reputable major I know of has done exactly that, and their pilots get three Sim sessions every six months instead of the customary two.

As always in modern life, the insurmountable stumbling block is put in place by the Beancounters.

bearfoil
4th Aug 2011, 19:16
And perhaps, commonsense? It has not in any way been established that manual flying issues played anything perhaps more than (possibly) a little too much NU one time? The rest is not manual skills, but SA, scan, and "knowing one's aircraft"? Not recognizing STALL is not perforce a manual skill?

overthewing
4th Aug 2011, 19:38
The senior F/O was Flying.

Bearfoil, can you explain to a puzzled SLF? I thought the junior F/O was doing the flying during the crisis, and had been left 'in charge', vaguely, by the Captain.

jcjeant
4th Aug 2011, 20:00
Hi,

JFFFC
- Should the captain have leave his seat to an adolescent yet he had a bad feeling ("Do you "really" have your licence ?"), furthermore in front of his girl friend ?

Dunno about the girl friend presence ... but what I know is that the crew on the flight deck from Rio to Paris .. was the same who make Paris to Rio ...
With that in mind .. I find it odd that the captain is concerned only for the return flight to the validity of the license of one of his copilot

bearfoil
4th Aug 2011, 20:07
overthewing

1. I am holding on to my perception of the "musical chaises" by a thread.

2. Discussing it gives me the 'vapors'.

3. I recommend a Movie: "Groundhog Day"

snug your lap belt. It will be choppy ahead.

oldchina
4th Aug 2011, 20:44
How can AF explain that there is no-one clearly in charge in the cockpit after the Capt leaves?

Paying pax wouldn't believe it. This has nothing to do with PF / PNF.

If the AP disconnects that is not the time to discuss who's the boss.

SeenItAll
4th Aug 2011, 21:15
Bearfoil and xcitation:

I fully agree that the pilots did not have a cakewalk presented to them. And in my previous posts I have always pointed out that things could have been quite chaotic on the flight deck, AB's stall warning was not their friend, and that from a very early point in the three-minute scenario, the plane may have been unrecoverable.

But that said, it does not appear that any concerted attempt was made to try the only thing that might have saved the plane once the sh__ had hit the fan at the top of the zoom climb, and that was sustained nose-down and trade some altitude for airspeed.

The question we face is "why?" Lack of training? Lack of non-AP flying experience? Lack of appropriate CRM? Or did the normal thought processes of the PF, PNF and Captain just simultaneously "freeze?" What I don't see is any way to lay the cause completely at AB's door. Surely the stall warning logic could be improved, but no piece of equipment is always infailable. Something will always go wrong, and that's why we have pilots. We have to figure out why they failed -- exactly at the time when the equipment/software failed -- and figure out what we need to do to fix it.

stepwilk
4th Aug 2011, 21:23
Is is not possible to rescue an unused DC-10 or DC-8 from the boneyard in Arizona, and fly it around Hudson Bay, say, with a retinue of trainees in the back, taking their turns manual flying?

Oh, yeah, that'll do it...sort of like my half-hour of CPR training three years ago. "Where do the hands go, again?"

Rob21
4th Aug 2011, 21:37
So the question now (for AF & AB) is:
We should give more training to the pilots or "teach" the computers to get out of emergencies?

Computer's way of "thinking" is very simple: "if this, go to that" and so on.
Of course, to "teach" a computer to solve emergencies, like UAS, will take some effort (and money).

Then, when an emergency occurs, the computer shall warn the pilot what is going on and "ask" him if what he is doing is OK.
Computers can "read" the whole Flight Manual in a split second.
The computer opens the page on "Unreliable airspeed", and says: "I am holding 2.5º pitch and applying 85% N1. If you don't agree, please press the DO NOT button".

The problem is, if we "teach" computers to fly these very complex stuff, it's actions will become normal, like today's protection laws are normal. Pilots rely on these laws.
And then emergencies will be "managed" by computers, under the supevision of the pilot. Nice, but if in a dark and stormy night the computer faces an emergency that is not listed?

If flight computing goes in this direction, computer engineers will be thinking that a computer can think. And I am not sure if they are not already thinking that computers can think a "little"...
But they can't (at least to my knowledge).

Wouldn't be easier to allow pilots to hand-fly a little?
Wouldn't be easier to give pilots more SIM time?
Maybe if we change "easier" for "more economical", companies will be "smarter"...

Rob21
4th Aug 2011, 21:50
Victor2, are you telling me ATC does not trust pilots any more?

Wouldn't be a nice deal hand-fly in an airspace where you can not gain or loose one hundred ft?

As I recall, in my commercial pilot flight check ride I was allowed to gain (or loose) only 50 ft on level flight, and turns. And I had to be quick going back to the right altitude.

Wouldn't be nice to show computers that pilots can fly too?

Thanks!

Lonewolf_50
4th Aug 2011, 22:14
Fox 3
No emergency procedures are verbally identified. No drills are done. No cross-checks of Attitude, or anything else, are called.
I'm not flying Air France again.
I have suggested to my brother, the international traveler, that he not use them at all until their process of correction (I guess a year or two) is gone through.
I have some experience lecturing on FBW flight controls, and instructing in a simulator. Aircrew tend to follow A drill, rather than do nothing. The usual reasons for following the wrong drill are rushing into action based on only one or two bits of information (probably the audio warning and the speed readout failure in this case), reverting to type (flying the aircraft/action they are most familiar with, e.g. TOGA loss of IAS)
YES. Seen it as well. Hell, done it myself.
Power, Attitude, Trim.
Unless in direct law, the trim is provided by HAL.

The PF is flying for 15 degrees NU, power is variable as he's not sure of speed. There's no trimming, probably because he's forgotten it.

HAL is trimming, not the pilot. That's a design feature. No coolie hat on the stick to trim with ...
In fact, I think he's going for at least 12 degrees Nose-Up attitude right from the start of the problem.
Question please, doesn't everybody memorise the Power/Attitude combinations for t/o, climbout, cruise, descent and approach any more?

This situation should have been met with.
Take control
Set 2.5 degrees nose-up attitude and 90% power.
Cancel warnings, identify loss of IAS readouts.
Get PNF to confirm diagnosis.
Run through drills.
Recall Captain to flight deck.

What it's met with is:
Take control
Fly unreliable IAS drill calling for 12/15 degrees nose-up attitude
Push power up when stall warner sounds (instinctive)
No correct communication with PNF

Succinctly put.

I do think the Captain's failure to formally divide the tasks before leaving the cockpit is important to the last point.
From a formal perspective, yes, I agree, however, given the reaction of the PF in this case, as the various bits of CVR are dribbled out to us, I suspect it may not have mattered.
There is some vidence of "do the wrong drill, and do it now" as the first domino to drop after the Auto Pilot stepped aside.

RWA
they didn't have speeds - and both the Flight Directors kept cutting out at intervals, so very probably they didn't have working artificial horizons either for long periods

Are you supposing that the Artificial Horizon is linked to pitot static system, or do you refer to the FD function rather than the "nose pitch" and "wing roll" attitude indication?

Does it exists a procedure that could have allowed the PNF to take control by strengh after the PF has re-taken control without annoucement yet the PF had admitted having lost the plane ?

Reach across the cockpit and punch him in the head with some force? That's a bit old school, but it has been known to result in a change of controls. (Don't ask me know I know ...)
JJFFC
2:11:37 : PNF takes controll after the PF having said 'I have lost the plane"
2:11:39 : PF re takes control from the PNF witout annoucement
2:11:42Captain enters
2:11:45 : End of CONTINUOUS stall
So the capt could believe the PF has save the plane but from 2:11:39 the PF is no longer a professional pilot.
In an army, had he survived, he proubably would have go to the martial court for insoumission.
Before 2:11:39, the PF was a bad pilot. From 2:11:39, he could well be judged as a criminal...


Ouch

infrequentflyer789
4th Aug 2011, 22:36
I don't think that the airbus design philosophy of a sidestick without feedback has caused the accident. Also, how do you generate the feedback when the speed data is lost? You can synthetize something based on the AOA vane sensor, but the fact that there was icing in this case precisely meant that all data was suspect. IMHO generating a feedback based on faulty sensors is even worse than no feedback at all.


You are right about control feedback being wrong in UAS (it can only be thus), but Conf wasn't talking about that sort of feedback but rather visual feedback of what the other guy is doing with the controls.

Whilst I agree that is a potential disadvantage of side stick, I actually don't think it is relevant here - PNF seemed to know perfectly well when PF was climbing or overcontrolling roll (in fact he seemed more aware than PF himself).

See also Bearfoils post(s) on the other thread: http://www.pprune.org/6619313-post1529.html


But that doesn't remove the fact that the stall alarm design is completely unnatural and misleading, which is a big design flaw.

It is, but I believe there are reasons behind that design and it would be foolish to just call for changes to it without understanding all the logic fully. Clearly the designers never thought a bus would be <60kts in the air, or maybe they thought if it was, it was already lost (may be right), or that the crew must have had enough warning of stall already by that point.

In this case, by the time the SW goes on vacation, the AOA is up at 30deg or more, airdata is going haywire due to high AOA, and the crew have seconds to recognise stall (where they didn't in previous minute of continuous warning) and push nose down over 30degrees (from full NU trim) to get anywhere close to a recovery. With no outside visual reference. And we're so far outside flight envelope we have no real idea how the airframe would have responded to controls. Was it really, practically (not theoretically) still recoverable at that point ?

grimmrad
4th Aug 2011, 22:47
"How can AF explain that there is no-one clearly in charge in the cockpit after the Capt leaves?"

Wouldn't one assume that that is automatically done through seniority or hours on type? Are there no SOP at AF that clarify that?

jcjeant
4th Aug 2011, 22:53
Hi,

grimmrad

Wouldn't one assume that that is automatically done through seniority or hours on type? Are there no SOP at AF that clarify that? Read this ... maybe it can help .....

http://www.pprune.org/tech-log/456874-af-447-thread-no-5-a-78.html#post6619789

bearfoil
4th Aug 2011, 23:03
I am no stranger to simplification, so here goes. It strikes me that what is involved here is less to do with hand skills than Pilot Attitude.

To accept that manual control failed here is to accept too large a wedge of the format. In NORMAL LAW, for goodness' sake, all pilot inputs are Manual.

No, the failure appears, at this early time, to be re: PREPAREDNESS. I will wager that PF had all the drills down, the changeover down the flying down.

He was not ready, and his skills were not ACCESSIBLE. No more "When I learned.....", please. He knew, and he knew he knew.

The wheels came off, and catch up is impossible when one's talents are not available. I am weary of the Mechanicals. There is likely some interesting metallurgy and design issues here, but I think they will be found secondarily. I love to discuss design and fabrication, and I leave open the window for bent or unstowed Spoiler, or compromised Jacks and Fuel issues.

Not too much the matter there. The ship seemed fine at 2:10:05. What happened next (and is still happening, one fears), has to do with some basics, and that, as a pilot, is embarrassing.

I am afraid I have expressed my feelings to all my family. Until further notice........check your options; Air travel is a luxury, address it as such.

xcitation
4th Aug 2011, 23:25
Bearfoil
So have you also told you family to stop driving, drinking and other much riskier activity than flying? Don't make me pull out the stats ;).

jcjeant
4th Aug 2011, 23:38
Hi,

Bearfoil
So have you also told you family to stop driving, drinking and other much riskier activity than flying? Don't make me pull out the statsHuman life (personnal life) is not driven by numbers or statistics ( we are not already computers).. but by personnal feelings ...
So I can maybe feel in better security in my car on a crowded highway .. than be seated in a AF plane :)

bearfoil
4th Aug 2011, 23:57
For many reasons, not the least of which I find to be BEA propaganda, Nonsense PR from All Three principals, and a lack of sincere consideration, Long haul flight on AF has become (unwittingly) problematic

OPINION: The fact that remote mathematical odds are thrown about, I consider it whistling past the graveyard. The loss of an autopilot for any reason (and I have NOT accepted UAS or ICE had effall to do with it) means that one of three potential Pilots may be responsible for an aircraft that has ventured into mathematical probabilities of a demonstrable ONE IN THIRTY THREE HUNDRED OF crashing to the surface of the EARTH.

The odds of losing an auto pilot (disconnection as well as through malfunction) might be, one in one hundred? The chance of encountering bunk MET in ITCZ is likely what, ONE TO ONE?

So, 1/33 UAS
1/100 AP LOSS
1/1 BUNK MET

I see a chance of ONE in 3300 of coming to serious grief on AF.

Tell me again how utterly safe AVIATION IS?

BRE
5th Aug 2011, 05:23
As this thread keeps growing faster than I can keep track, bear with me if these questions have been asked before:

1. Had the PNF pressed the takeover button, would the PF have been able to re-take control?

2. Is it normal for a crew at AF:
- not to be using standard calls (maybe even in English), but informal French throughout?
- to be addressing each other with the familiar "tu" in spite of the age and authority gradient?

3. Just for comparison, what is the official cockpit language in say KLM or LH?

RWA
5th Aug 2011, 05:38
Confess to still being ‘bugged’ by the issue of the THS going to ‘full up.’ Unfortunately the BEA doesn’t say much about it in the latest report – and what it does say is rather contradictory.


Page 10 - "At 2 h 10 min 51, the stall warning triggered again. The thrust levers were positioned in the TO/GA detent and the PF maintained nose-up inputs. The recorded angle of attack, of around 6 degrees at the triggering of the stall warning, continued to increase. The trimmable horizontal stabilizer (THS) began a movement and passed from 3 to 13 degrees pitch-up in about 1 minute and remained in the latter position until the end of the flight."

That’s just a repeat of the section in the earlier report.


Page 75 - "Despite some nose-down inputs, the PF maintained nose-up inputs overall. Pitch attitude fluctuated between 11° and about 18° and the angle of attack between 11° and 23°. The THS began a movement that was consistent with the PF’s inputs and reached 13° nose-up about a minute later. It should be noted that in alternate law, the auto trim is still active. On the other hand, it is difficult for the crew to know the trim position and there is no warning to the crew that it is moving."

The important thing there, to me, is that autotrim was still in operation.


Page 77 - throughout the flight, the movements of the elevators and the THS were consistent with the pilot’s inputs,

That’s the contradictory bit. As far as I can see, from the chart on page 111, the THS movements simply weren’t ‘consistent’ with the pilots' inputs at all. Indeed it appears only to have made the one movement – to ‘full up’- during the whole episode.

On Page 111, the pale blue line under ‘STABILIZER POSITION’ appears to show that it didn’t move at all at first. Then, at about ‘2.10.50,’ it began to pull up. This movement seems to have started during a period when the PF (shown as ‘CAPTAIN’) was putting in quite a lot of small movements both ways – none of which seem, on the face of it, to have been large enough to trigger such a huge movement by the THS? The THS movement finished (i.e. reached ‘full up’) at about ‘2.11.50. From then on the THS seems just to have remained at ‘full up,’ and didn’t respond to any of the further stick inputs made by both the pilots?

Can anyone with more knowledge of the aircraft and its systems – bearing in mind that the BEA says that autotrim was still in operation - explain why the THS would have behaved in this (on the face of it, very strange) way?

Is it possible, for instance, that the autotrim was responding not to the pilots’ inputs but to the very low Indicated Air Speed, or to other irregularities ‘reported’ by the sensors?

bubbers44
5th Aug 2011, 05:51
Sounds like Airbus safety could be enhanced by low time pilots getting high altitude hands on flying so they don't zoom 3,000 ft into a deep stall when the autopilot fails. Also explain to them that holding back on the SS once in a deep stall is not a good idea. Just a thought.

zekeigo
5th Aug 2011, 05:53
Authority gradient??? In Europe the FO's think and act as they have the same status as the captain, and the EU captains accept that. Had many attitude behavior problems flying with European FO's, but when the S hits the fan they say "You're the captain, it's your problem"…
Until they understand the "Leaders and Followers" rules, conflicts in the cockpit will exist and flight safety will be jeopardized.

mm43
5th Aug 2011, 09:12
Originally posted by RWA ...

Can anyone with more knowledge of the aircraft and its systems – bearing in mind that the BEA says that auto-trim was still in operation - explain why the THS would have behaved in this (on the face of it, very strange) way?I believe the outcome is due to the THS being 'g' driven. In other words, the SS command was given that allowed the actuator to take the elevator to maximum NU, but the expected 'g' didn't occur and the THS moved to (try) correct that situation.

In explanation - the THS will always attempt to neutralize the position of the elevator, and if necessary readjust according to elevator demand.

If I am wrong, you will soon find out.;)

HazelNuts39
5th Aug 2011, 09:33
My understanding from the Perpignan report is that, with autotrim in operation, the THS only moves when the elevator goes past the neutral position: nose down elevator will command the THS to move more nose down. The elevator follows the (g-driven) SS orders. So a small nose-down command from the SS that causes the elevator to move from nose-up to less nose-up without going to nose-down will not cause the THS to move.

rollnloop
5th Aug 2011, 10:33
1. Had the PNF pressed the takeover button, would the PF have been able to re-take control?

Yes, pressing the take over button himself. Last one pressing has commands.

2. Is it normal for a crew at AF:
- not to be using standard calls (maybe even in English), but informal French throughout?

No. This shows much stress.

- to be addressing each other with the familiar "tu" in spite of the age and authority gradient?

Standard use. At AF the last in F/O will use "tu" in cockpit with the most senior pilot in airline if they're to fly together. It spares a few syllabs. After all, "you" can mean both "tu" and "vous", it's practical to decide for only one word and "tu" helps forming a team spirit. All crew uses "tu", except in cabin where "vous" is used. Sometimes F/A use "vous" talking to captain, mostly when they're white/grey haired.

eSpoiler
5th Aug 2011, 10:43
As a very part time passenger and model plane pilot, I have followed this threads with interest. The CVR and FDR data is horrifying - I would have thought that professional pilots would have behaved very differently in such a situation. I could imagine myself as thrown into that situation and doing no worse than the PF did - perhaps better when it came to stick inputs. That is scary.

On a recent flight I noticed the issue mentioned in a couple of comments - that is the loss of sense of aircraft orientation. I could have sworn the plane was level but when I looked out saw thet the wings were banked and the plane was turnning left. I can only imagine how hard it must have been for these pilots to sense what the plane was actually doing withouit any horizon on a pitch black night, with what appeared to be unreliable instrumentation.

I guess that is when training and professionalism is meant to take over...

Lonewolf_50
5th Aug 2011, 12:55
For those who have flown the A330:

How many key strokes (steps) does it take to call up the F/CTL ECAM System Page on the SD. This screen shows where the rudder and THS are, and what the spoilers are doing, what spd brks are or aren't doing, and a prim/sec status. It also looks to tell you which hyd system is up or down as related to a given flight control.

Does this screen get auotmatically pre-empted by rising ECAM alerts, or does is stay active once selected?

Background thinking to my question:

About 20 years ago, something as simple as switching Radio Freqs went from a simple manual task of turning a button here or there, to a process which requires opening a screen and typing in freqs. (This was in the SH-60F). As I had never had trouble with switching radios by hand, I looked into this and noticed that it takes MORE time and steps to switch radios via software. From a pilot task loading perspective, this was idiotic. It appeared to me one of many "solutions" looking for a problem. On that aircraft, the sole FBW control surface was the horizontal stabilizer. (Sorta like the THS in A330, but different). A single, small gauge in the lower center of the instrument panel told you where the stab was at all times. (It was mostly controlled by an auto trim feature). This gauge was a cross check instrument, not a primary scan instrument. You only needed it if things were a bit wrong with the electronics. There was also a manual control that overrode the electro-trim and allowed you to fix its position as needed.

Back to THS on an A330.

I don't know if the crew in AF447 would have thought to look at where their THS was ... but ... if the PNF had wanted to, how many steps in sequence would it take to discover where that control surface was positioned?

RWA
5th Aug 2011, 14:59
mm43, HazelNuts39, thanks so much for the informative replies.

Quoting HazelNuts39:-

My understanding from the Perpignan report is that, with autotrim in operation, the THS only moves when the elevator goes past the neutral position: nose down elevator will command the THS to move more nose down. The elevator follows the (g-driven) SS orders. So a small nose-down command from the SS that causes the elevator to move from nose-up to less nose-up without going to nose-down will not cause the THS to move.

I read the BEA's Perpignan report (on a accident back in 2008) but missed the point you very kindly brought up. To quote part of the report:-


"From 15 h 44 min 30 the automatic trim function displaced the stabiliser as far as the electric nose-up thrust stop (- 11 degrees). The stall warning sounded at 15 h 45 min 05. The nose down commands applied by the Captain on the sidestick brought the elevators, due to the load factor, to the neutral position, without however pushing them to the stops. Consequently, the trimmable stabilizer did not move even though the flight control law was normal. From 15 h 45 min 15 until the end of the flight, the automatic trim function remained unavailable. In fact, the direct law was active from 15 h 45 min 15 to 15 h 45 min 40 and the Abnormal attitude law phase 1 (without auto-trim) remained active till the end of the flight.

"Footnote:- The elevators must go beyond the neutral position before the auto trim function adjusts the position of the stabilizer.

"When the stall warning sounded, the Captain reacted by placing the thrust levers in the TO/GA detent and by pitching the aeroplane down, in accordance with procedures.

"The nose-down input was not however sufficient for the automatic compensation system to vary the position of the horizontal stabilizer, which had been progressively deflected to the pitch-up stop by this system during the deceleration."

So, as I read that, in order to get the THS even to start moving back to a sensible angle, the Perpignan pilots (and later the AF447 ones) would have needed to shove the stick full forward and hold it there for quite a while, until the THS 'accepted the situation' and started moving back from 'full up.'

But, of course, on AF447, every time they attempted that, the airspeed increased and they got another 'stall warning.' And presumably thought they were 'doing it wrong' (what, apart from an engine falling off, can be more serious than an impending stall?) and instinctively relaxed the stick pressure.......

It'd be interesting to know whether Airbus, Air France, or the BEA had warned pilots that this sort of 'impasse' could occur; and indeed had occurred, as far back as Perpignan in 2008? I very much doubt it........

Anyway, thanks again - I now know, to my own satisfaction, the primary causes of this latest accident. And, in my view, they weren't entirely, and possibly weren't even mainly, 'pilot error.'

lomapaseo
5th Aug 2011, 15:06
Have the investigators (BEA) stated that the zoom climb was commanded by the pilot (stick) or is the jury still out considering that a computer function did it unrecognized by the pilot?

I focus on this early event as a possible critical causal factor needed to take a benign failure condition (temporary lack of reliable airspeed) to a severe condition.

To me this is a critical finding, because we can'y elliminate all failure conditions (ala loss of airspeed) etc. We are left with strengthening a minimization factor like pilot training. If there is another critical area that can be worked on in this causal chain that would greatly minimize a repeat of the event chain leading to a fatal accident.

DC-ATE
5th Aug 2011, 15:13
Unfortunately, this was an Airbus accident and this thread will no doubt go on for another One Hundred Thirty plus pages ! Had it been a "real" airplane, "case would've been solved" a Hundred pages ago. Naturally, IMHO. :*

JJFFC
5th Aug 2011, 15:17
IMHO The causes are :

1 The decision of the PF to climb, yet the PNF has told him the temp. was to high;
2 The decision of the PF to re take control from the PNF without annoucement and to climb again yet the PNF has urged him to nose down.

These two decisions of the PF are not a reaction to any information from the plane.

They came from his will and only his will.

The first decision leads directly and logically to a stall;

The latter decision prevented the PNF from recovering the plane.

None of these decision should have come from a Professional Pilot.

These decision had nothing to do with training nor CRM, design etc.

Furthermore, the Captain had a nasty feeling proved by his odd question : "Do you have your licence ?" to somebody that had made the journey with him from Paris.

I really think that it should be investigated to understand in which psychological or physical conditions he was.
I believe that the very short time between the entering of the Captain and the level 100, barely allowed him the time to understand that the PF was climbing against all skills. When this was established, then the PNF could took the control again under the Capt. authority. But it was to late.

I believe that tço many people here and in the press don't make the distinction between the period before teh PF re take control of the plane and the short sequence after.
The BEA should have divided the time around this KEY action:

- Because the PNF needed the authority of the Capt to take control except if he were Rambo.

- Because when the Capt. enters, he doesn't see the end of the stall caused by the first decision of the PF. He lives a NEW sequence just after the PF had RE taken the control and that he climbed again, entering in a new stall.
Too short for the Capt to understand.

jcjeant
5th Aug 2011, 15:19
Hi,

Can anyone explain me this (it's extracted from the BEA report french edition page 23)

http://i.imgur.com/hFfhC.jpg

 Enregistreur de paramètres - FDR

 Marque : Honeywell
 Modèle : 4700
 Numéro de type (P/N) : 980-4700-042
 Numéro de série (S/N) : 11469 :confused::confused:

JJFFC
:ok:

SLFinAZ
5th Aug 2011, 15:57
The more and more I read the more concrete it seems that the "zoom" was initiated by PF input to the SS not as a result of AP disconnect (which was a point of confusion to me). This is a significant deviation from the previous theory that the AP "wound out" until it reached the end of it's capabilities and handed the plane off in an entirely unstable condition.

Am I correct in my understanding that the climb was in fact initiated by proactive input and that the subsequent trim changes are a result of the auto trim responding to the SS inputs?

Given the very serious issues involved in approaching max altitude even with full instrumentation (let alone under the circumstances involved) any decision to gain altitude would appear to be fundamentally incorrect and display a complete lack of basic airmanship. What pilot would knowingly fly an airplane with degraded systems closer to coffin corner? Did not the senior pilot on the flight deck have a clear responsibility to forcibly (in the verbal sense) take command if required?

I have been unable to find reference to the captain questioning the PF's credentials (was this before the upset? before the flight?). If the captain had enough concerns to actually make a comment then how does he allow this individual to actually be the PF when he retires from the cockpit????

RWA
5th Aug 2011, 16:29
Quoting Lonewolf50:-

Back to THS on an A330.

I don't know if the crew in AF447 would have thought to look at where their THS was ... but ... if the PNF had wanted to, how many steps in sequence would it take to discover where that control surface was positioned?

Looked it up (can't find the photos again) and the conventional (non-electronic) A330 setup looks pretty good. Big trimwheels either side of the central console, and (I checked :)) they're servo-assisted, and actually move! :)

However, the wheels don't give you the pitch angle; they just have the 'usual' setup, white marks every 15 degrees or so. Apparently there are gauges beside the wheels that give you the angle - how well illuminated they are, and how easily you could read them at night, I just don't know.

Point that occurs to me, though, is that the autotrim was still operating? So, even if the pilots had thought to check the trim settings and maybe wind the wheels forward a bit, presumably the 'systems' would just have wound the things back to 'full up' again?

overthewing
5th Aug 2011, 16:32
@SLFinAZ
I have been unable to find reference to the captain questioning the PF's credentials (was this before the upset? before the flight?). If the captain had enough concerns to actually make a comment then how does he allow this individual to actually be the PF when he retires from the cockpit????

Page 73 of the BEA Interim report:

A little after 1 h 52, the turbulence stopped. The copilot drew the Captain’s attention to the value of REC MAX, which then reached FL 375. The Captain made no comment and, a few moments later, he woke the second copilot, said he was taking his place, and asked the copilot in the right seat if he had a commercial pilot license. He thus ensured that he was qualified to act as relief and implicitly designated him as relief pilot. This question to the copilot probably meant that the issue of the relief pilot for the Captain had not been raised during the briefing before the flight.

ChristiaanJ
5th Aug 2011, 16:34
Hi,
Can anyone explain me this (it's extracted from the BEA report french edition page 23)
http://i.imgur.com/hFfhC.jpg
 Enregistreur de paramètres - FDR

 Marque : Honeywell
 Modèle : 4700
 Numéro de type (P/N) : 980-4700-042
 Numéro de série (S/N) : 11469

What do you want "explained" ?
It's the Honeywell part number and serial number of the FDR memory module.

jcjeant
5th Aug 2011, 16:36
EDITED

Cross posting :)

I have been unable to find reference to the captain questioning the PF's credentials (was this before the upset? before the flight?). If the captain had enough concerns to actually make a comment then how does he allow this individual to actually be the PF when he retires from the cockpit???? English report N°3 page 73
A little after 1 h 52, the turbulence stopped. The copilot drew the Captain’s attention to the
value of REC MAX, which then reached FL 375. The Captain made no comment and, a few
moments later, he woke the second copilot, said he was taking his place, and asked the
copilot in the right seat if he had a commercial pilot license. He thus ensured that he was
qualified to act as relief and implicitly designated him as relief pilot. This question to the
copilot probably meant that the issue of the relief pilot for the Captain had not been raised
during the briefing before the flight.

jcjeant
5th Aug 2011, 16:38
Hi,

What do you want "explained" ?
It's the Honeywell part number and serial number of the FDR memory module.

Well ... put your spectacles again on your nose (or use binoculars) :8
The SN number of image and txt report are not corresponding (different !!)
Page 23

KBPsen
5th Aug 2011, 16:48
The SN number of image and txt report are not corresponding (different !!)Of course they are not.

The image is of the CSMU, the memory module. The 'text' P/N and S/N is from the FDR chassis on which the CSMU was mounted.

jcjeant
5th Aug 2011, 17:01
Of course they are not.

The image is of the CSMU, the memory module. The 'text' P/N and S/N is from the FDR chassis on which the CSMU was mounted. If you right ... this is odd to the BEA to publish a image and a legend not corresponding ....
That's not serious ...

EDITED
And you no right !
For the FDR, only the protected unit (CSMU or memory module) was present. The CVR was
complete.

 Flight Data Recorder - FDR

 Manufacturer: Honeywell
 Model: 4700
 Part number (P/N): 980-4700-042
 Serial number (S/N): 11469

ChristiaanJ
5th Aug 2011, 17:03
Of course they are not.
The image is of the CSMU, the memory module. The 'text' P/N and S/N is from the FDR chassis on which the CSMU was mounted.Thanks KBPsen, I thought it was a genuine question, not another effort at a conspiracy theory 'à la Asseline'. I should have known better....

jcjeant
5th Aug 2011, 17:05
Thanks KBPsen, I thought it was a genuine question, not another effort at a conspiracy theory 'à la Asseline'. I should have known better....


Read my post above !

KBPsen
5th Aug 2011, 17:28
That's not serious ...So they should have published a picture of the FDR chassis that was neither found nor recovered? Who is it that is not being serious here?

dlcmdrx
5th Aug 2011, 17:44
related to the thread:

AFP: Rio-Paris jet crash probe 'discredited': relatives (http://www.google.com/hostednews/afp/article/ALeqM5hrVSDCE0utQvAFCn7MkGcLKGmjaw?docId=CNG.0dcc70d787af82f 2b283aeb2af9d940e.821)

overthewing
5th Aug 2011, 18:29
Do we know whether the FDR chassis was retrieved, or only the memory module?

Identifying a part that they didn't recover is confusing. If the identification is really based on an integrated component (the memory module), then additionally reporting the part /serial numbers of the memory module would seem sensible.

jcjeant
5th Aug 2011, 18:46
So they should have published a picture of the FDR chassis that was neither found nor recovered? Who is it that is not being serious here? Sorry but:
Or you don't understand .. or you are blind ..

They published a picture of a module .. and this with the legend FDR
This module on the picture have a plate with a SN
This SN is not 11469
And after they give the specifications (N°) of the FDR module (they have not the chassis)
The serial N° is 11469

For the FDR, only the protected unit (CSMU or memory module) was present. The CVR was
complete.

 Flight Data Recorder - FDR

 Manufacturer: Honeywell
 Model: 4700
 Part number (P/N): 980-4700-042
 Serial number (S/N): 11469 So I conclude this is not serious
This no rereading (verification) before the report release (no peers reviewed .. as it must be from a serious agency)

Lonewolf_50
5th Aug 2011, 18:49
PARIS — Victims' relatives and a pilots' union Wednesday said they had lost faith in a probe into the 2009 crash of an Air France jet that killed 228 people, alleging it sought to clear Airbus of responsibility.

The Goodrich probe or the Thales probe? :E

I note the semi-histrionic language, but I feel the pilot's union has a defensible point about the stall warning as possible factor influencing cockpit decisions during attempts at remedy/recovery.

SLFinAZ
5th Aug 2011, 18:50
Thank you for the clarification, so the "do you have your commercial license" is a procedural question and not a reflection of of the captains perception of his skills as an aviator. This leads me to a couple of follow up questions:

1) I always thought that routes like this one normally drew from a relatively small cadre of pilots with the seniority to bid on that route successfully, further that the crew origination was in Paris so this would be the return leg. I'd assume the captain would be aware of his crews credentials based on prior experience or would "interview" and review credentials for anyone he'd never flown with before flying with them....especially on a flight that called for him to be away from the flight deck at some point.

2) My second assumption is that in the event of any unusual circumstances the senior officer on the flight deck is in command in the captains absence regardless of who is "designated" as the "PF" (given both are in reality just monitoring systems). Once the AP kicked off and the 1st fault display occurred the senior FO had a clear cut responsibility to take control of the aircraft the moment he felt the need to correct the actions of the PF. Had he simply said "my aircraft" more then likely this would be no different then any other similar incident relating to A330/340 issues.

To me this is a clear cut failure in the command and control culture for the airline in question. I am also amazed that the captain did not immediately take his seat back. Regardless of any other circumstances for the aircraft to hit the water with the captain having never taken control of the aircraft speaks volumes about very serious cultural issues (again my opinion).

When you view this incident in the frightening context of its current representation it drives home the reality that we are on the cusp of some significant precipice. For a major "flag" carrier to have flight crew trained to such a low standard that they were incapable of handling what should have been a "minor emergency" is appalling. I can not fathom a company culture that would allow a more seasoned FO who actually knew what to do sitting by while he literally watched an obviously overwhelmed pilot kill not only himself but the souls for which he had responsibility in the captains absence.

While it might be possible to rationalize this accident within the context of a regional airline like Colgan, a "third world" airline like Libya (Afriqiyah) or a national flag carrier where significant cultural issues impede cockpit CRM (Turkish Airlines) how do you do so with a flagship western carrier?

To me it's a very clear wake up call that the obvious benefits and economies of automation have led us to a point of not only diminished returns but significant risk. When even major western carriers have reached a point where 5,000 hr FO's no longer have the fundamental skill set (and cockpit culture) to handle readily foreseeable contingencies.

jcjeant
5th Aug 2011, 18:53
Hi,

The Goodrich probe or the Thales probe? Probe in the context is "investigation" !

PARIS — Victims' relatives and a pilots' union Wednesday said they had lost faith in a probe (investigation - my edit) into the 2009 crash of an Air France jet that killed 228 people, alleging it sought to clear Airbus of responsibility.

CelticRambler
5th Aug 2011, 18:53
From Le Figaro's inside source: Unpublished CVR (http://www.lefigaro.fr/actualite-france/2011/08/05/01016-20110805ARTFIG00446-af-447-ce-que-les-enqueteurs-du-bea-n-ont-pas-dit.php)

An article hinting at some of the dirt yet to be thrown, but possibly also explaining the sudden withdrawal of cooperation ... :uhoh:

Il est 0h15 à bord du vol AF 447 (http://www.lefigaro.fr/actualite-france/2011/07/25/01016-20110725ARTFIG00350-af-447-le-rapport-d-etape-de-l-accident-publie-vendredi.php). Alors que tous les avions présents sur la zone ont choisi ou vont choisir de modifier leur route pour éviter une zone de cumulonimbus, le commandant de bord du vol AF 447 dit à son collègue: «On ne va pas se laisser emmerder par des cunimbs.» Les «cunimbs» sont les cumulonimbus chargés de glace qui peuvent entraîner un givrage des sondes Pitot. L'AF 447 est le seul avion, la nuit du 1er juin, à avoir poursuivi sur une route rectiligne. Il ne modifiera sa trajectoire que de 12 degrés en arrivant à proximité du phénomène météo. Il sera alors trop tard pour l'éviter. Vingt minutes avant le crash, le commandant de bord annonce: «Ça va turbuler quand je vais aller me coucher.» Puis au moment de quitter le cockpit: «Bon allez, je me casse.» Le commandant de bord est donc allé se coucher en connaissance de cause juste avant les turbulences qui ont marqué le début du drame.

For the benefit of non-francophones, the quoted speech translates as "We're not going to let ourselves be messed about by some CNs [i.e. reason for not deviating] ... that'll be [pretty rough] when I go for my rest ... Right, I'm off."

According to the article this section of the recording was excluded from the interim report because "it didn't add to the explanation of what caused the accident". I suspect the criminal investigation will think otherwise. The inside source also reports that Air France is dragging its heels with regard to providing the BEA with full details of the crew's training. You'd almost wonder if someone in the BEA lost a relative in the crash and has decided there's no honour in protecting AirFrance just because it's French ... :sad:

jcjeant
5th Aug 2011, 18:59
Hi,

From Le Figaro's inside source: Unpublished CVR (http://www.lefigaro.fr/actualite-france/2011/08/05/01016-20110805ARTFIG00446-af-447-ce-que-les-enqueteurs-du-bea-n-ont-pas-dit.php)

If this is true .. it looks like the beginning of a funeral march for Air France as to the quality of its pilots and for the BEA about it's transparency ....

grimmrad
5th Aug 2011, 19:09
Regarding the question about a license... does that mean you can be pilot in a major carrier WITHOUT the license??

In my profession you cannot even touch a patient under your own responsibility and without supervision without proper certification!

Neptunus Rex
5th Aug 2011, 19:13
So, as I read that, in order to get the THS even to start moving back to a sensible angle, the Perpignan pilots (and later the AF447 ones) would have needed to shove the stick full forward and hold it there for quite a while, until the THS 'accepted the situation' and started moving back from 'full up.'Not quite. Manual pitch trim should have been available in both cases.

KBPsen
5th Aug 2011, 19:25
Sorry but:
Or you don't understand .. or you are blind ..

Or I am not seeing the reports as an opportunity to find fault no matter how contrived or twisted.

As you obviously do not know what a FDR looks like or is comprised of, let me educate you.

There is a chassis, a CSMU and a ULB. The CSMU is mounted on the chassis and the ULB on the CSMU. Each has it's own part and serial number.

The entire assembly is called FDR.

BEA shows the recovered part of the FDR, which is the CSMU. They also list the FDR from which it came by maker, model, part and serial number.

It is only in your biased layman's mind that there are any inconsistencies.

thermalsniffer
5th Aug 2011, 19:30
I am sorry, but I do think the BEA has lost a tremendous amount of credibility here in the withholding such information, IF THIS IS TRUE.

IF TRUE, the failure to deviate is very relevant to the accident (one of the Swiss Cheese holes), otherwise why publish the deviation map of the other flights. Many in all the threads have asked a fundamental question of "why did they not deviate?" To me this is as fundamental as "why the zoom climb?" in the understanding of this accident.

IT MAY NOT BE TRUE. I remember some reporting about the Captain rushing into the cockpit and saying "this is a stall." I have yet to see that.

So PF is a bad pilot he pulled up.
Now CAP is bad pilot he did not deviate and flunked a check ride or sorts.
Next watch out PNF.

Jazz Hands
5th Aug 2011, 19:41
I haven't seen anything that suggests any lack of integrity with the BEA investigation. On the other hand, I have seen a lot of desperate attempts to avoid pinning any responsibility on Air France and SNPL. I was given an insight today into just how deep the animosity and frustration runs regarding the stance adopted by Air France and SNPL. The rot started with the BS over the "conspiracy" at Habsheim and doesn't seem to have dissipated. :ugh:

jcjeant
5th Aug 2011, 19:41
Hi,

Regarding the question about a license... does that mean you can be pilot in a major carrier WITHOUT the license??

In my profession you cannot even touch a patient under your own responsibility and without supervision without proper certification! Well ... with the question about license from the captain in mind .. seem's that is possible .. at least on AF aircrafts ...
It's also possible to have a false license (as shown in the past and not particular to Air France)

In my profession you cannot even touch a patient under your own responsibility and without supervision without proper certification!

I suppose it's the medical sector
It's not the first time that press reports shown a plumber touching a patient in a hospital .. and even practising for weeks before it was discovered :8

DozyWannabe
5th Aug 2011, 21:02
Hi all,

Took a day's "sabbatical", getting too involved...

DWBirgenair was different, because the lower ranked FO knew what was happening

As did the PNF in this case, judging by the CVR.

The FO could have overpowered Capt. by pushing harder on the yoke. Could he have done that with a joystick?

If he'd called "I have control" and pressed the priority button, of course he could have. The issue for the Birgenair F/O, as it was for the AF447 PNF was that he wasn't assured enough of his assessment of the situation to take positive control and hold it.

As for your argument that the 777 backdrive can fail: it's built to the same safety standards as the Cat IIIc autoland, i.e., 10 -(7?) probability of undetected failure.

As are the Airbus systems, so why trust one system and not the other?

are you saying that the nose ups did not cause the stall warning.

I'm saying the stall warnings were triggered by the flightpath, not the input - so to say the situation regarding stall warning needs addressing is true, but to argue that the stall warning significantly and repeatedly stopped the PF from doing the right thing (nose down) because the warnings were triggered *as a result* of his nose-down input is untrue.

Fair enough in its way, Dozy, mate.

But looking at it another way, for a bit longer than aeroplanes have been around, bicycles have. It would be perfectly possible, with today's 'electronic aids,' to design a bicycle that didn't need handlebars; so that the rider could turn just by 'body lean,' with his/her hands in their pockets....:)

But no-one has yet designed a bicycle that works that way. I'd venture to say, because yer av'rage rider would get a bit confused......

But in fact there have been plenty of alternative bicycle designs that riders have adjusted to (I see them every time I'm in town), so I don't see the correlation.

So precisely WHY, in your opinion, did Airbus opt for 'no feel/no feedback' etc.? A revolutionary change, after the best part of a century of producing aeroplanes that all 'worked' the same way?

My own view is that it was a matter of 'less weight/lower cost.' I can't think of any other reason?

Maybe you can?

Well yes - for a start there's systems complexity, which is the engineering axiom that for every feature you introduce, what comes with that feature are additional potential points of failure. This was the first FBW airliner - it follows that you'd want to keep the systems as simple as possible. These requirements had been drawn up since 1982 *with input from pilots*, who didn't think that going from yoke to sidestick would be a big deal. Indeed, if it was as big a deal as some make it out to be, why have there been no hull-losses caused by the lack of interconnected sidesticks, and why is there clear evidence that at least one airliner with "classic" controls suffered the same fate?

What bugs me about the whole Airbus FBW deal and how a specific subset of the piloting community perceives it is that it started with the press. It was the press that started asking questions like "How long until we have a pilotless airliner"? It was the press that was used to spread misinformation such as "The A320 thought it was landing and overrode the pilot". Over the years I've looked into it I've seen statements from otherwise sane men and skilled pilots that include rubbishing the A320 versus the B737 by comparing the Citroen 2CV with the Ford F-100. I've read assertions that Airbus make "plastic planes" that will disintegrate at the first sign of trouble despite the fact that the first A320 to crash mushed into a forest and remained intact, an A320 landed on the Hudson and everybody got out, and that the only airliner to survive a missile strike and land safely via engine power despite the loss of all hydraulics was an A300. I've seen accusations that Airbus are the only manufacturer to try to influence the outcome of accident investigations despite the infamous DC-10 "Gentlemen's agreement" and Boeing's efforts to pin UA535 and USAir427 on pilot error in the '90s. All of this has been borne from a prejudice that seems to stem from the idea that Airbus have been trying to sideline pilots - including by introducing the 2-person cockpit (not true - the first 2-crew aircraft were the BAC 1-11, DC-9 and Jurassic 737), by introducing complex computer systems that pilots were unable to understand (again, not true - the first accident caused by overreliance on a sophisticated autopilot was EAL401 - an L-1011, and another famous one was AA965 at Cali - a B757) and by designing and building an aircraft that was a "beancounter" and engineering dream, but froze out pilots in the design process (see before - pilots were involved in the A320's requirements-gathering phase). I've also seen plenty of references to Bernard Ziegler, and some of the less-than-clever (with hindsight) things he said, but very few references to Gordon Corps, who was a pilot's pilot and very much enthusiastic about the A320's potential.

All of these misconceptions could have been avoided by doing a little reading and finding out what the actual state of affairs was, but instead the easy option of bashing Airbus for apparently being anti-pilot, anti-safety and (God forbid) French seems to still have a surprising hold amongst some pilots, and all of it came from the same lazy reporting that is so frequently decried on these forums when the press gets something wrong.

I know some on here probably see me as an apologist for Airbus and for technology, but I can assure you I am completely neutral - I just can't abide prejudice that stems from being misinformed.

That’s the contradictory bit. As far as I can see, from the chart on page 111, the THS movements simply weren’t ‘consistent’ with the pilots' inputs at all. Indeed it appears only to have made the one movement – to ‘full up’- during the whole episode.

If you follow the general trend of the inputs over time, you'll see that the THS was just doing as it was designed to do - compensate for the pilot's inputs and hold trim accordingly. The problem is that if you compare the amount of flight surface movement commanded by the FMC to maintain altitude and heading in turbulence with the amount that was commanded from the PF's sidestick following FMC disconnect, you see a glaring difference. The THS did what it did because the PF was inexperienced at high-altitude manual flying and was overcontrolling.

katie2931
5th Aug 2011, 21:16
Hi. This may seem like a rather simple question from a normal girl interested in all thing aviation after lots of flying over the globe... so forgive me but why did the pilots not actually 'feel' they were descending rapidly? would it not be obvious that they were stalled and falling out of the sky? No g forces?? Thankyou :)

funfly
5th Aug 2011, 21:27
You get the distinct impression that they did feel that they were falling but thought it was nose down.

ankh
5th Aug 2011, 21:30
> would it not be obvious that they were stalled and falling out of the sky? Good question; that's why I asked above if the pilots could distinguish a stall from a "high speed stall" because I was wondering the same kind of thing. In the dark, in storm turbulence, I wondered if there was any way they could tell which kind of stall, assuming they believed the alarms; as I recall the moves required for recovery would be different.

Karel_x
5th Aug 2011, 22:27
When they were falling with constant descent rate, about 10.000 ft/min, they cannot find it by their senses. They could discovere it by the instruments (altimeter, variometer) in combination with their nose up attitude (by artifical horizon). If they had an AoA meter, the could discovere it seeing extreme angle of attack.

jcjeant
5th Aug 2011, 22:55
When they were falling with constant descent rate, about 10.000 ft/min, they cannot find it by their senses. They could discovere it by the instruments (altimeter, variometer) in combination with their nose up attitude (by artifical horizon). If they had an AoA meter, the could discovere it seeing extreme angle of attack. At least ....
At the speed with which they came down .. they would certainly have some effect at the eardrums due to pressure difference ... (hurt feeling)
Even at reasonable rate of descent you feel this (even if cabin pressurised)

xcitation
5th Aug 2011, 23:01
Hi. This may seem like a rather simple question from a normal girl interested in all thing aviation after lots of flying over the globe... so forgive me but why did the pilots not actually 'feel' they were descending rapidly? would it not be obvious that they were stalled and falling out of the sky? No g forces?? Thankyou http://images.ibsrv.net/ibsrv/res/src:www.pprune.org/get/images/smilies/smile.gif


What makes you think they weren't feeling the rapid descent?
Commercial pilots are trained to fly by instruments and not to obey their perceived motion. In zero visibility it is even more dangerous.

Teddy Robinson
5th Aug 2011, 23:06
This comes down to scan, and basic IF skills. IF one is programmed to be protected, and the warnings are not fitting the picture, you either revert to basic skills or try to figure out what "it" is doing all the way down to sea level.

What it looks like to my humble bit of experience anyway.

I was non Airbus trained in the industry, then type rated on it .... perhaps the best way.

larssnowpharter
6th Aug 2011, 01:21
A couple of questions:

1. Given that the BEA Interim Report seems to be pointing a finer at EASA and Air France:

that EASA review the content of check and training programmes and make mandatory, in particular, the setting up of specific and regular exercises dedicated to manual aircraft handling of approach to stall and stall recovery, including at high altitude.

and that AF have introduced additional training cf:

5.1.3 Crew training
Training in a flight simulator
Additional session entitled “Unreliable IAS”:
 Summer 2009 (A320, A330/340)
 Booklet and briefing from the session: key technical points, HF and TEM (Threat and
Error Management) considerations
 Revision of emergency manoeuvres, at take-off and in cruise.
 High altitude flight in alternate law
 Approach to stall, with triggering of the STALL warning
 Landing without airspeed measurement information
 Associated briefings (all cockpit crew):
o Weather radar
o Ice crystals
Note1: This information has been integrated into the type ratings.
Note 2:

Is there anyone out there who can draw a direct comparison between the training the AF crew had and their own experience? In other words, was the AF crew trainíng 'par for the course' compared to other operators or sub par?

2. Which of the 2 co-pilots was PF?

exeng
6th Aug 2011, 01:46
My personal "artifical horizon" always works:


Well in this scenario your artificial horizon may not have worked quite as you have expected.

With a 15 degree nose up attitude with a very high rate of decent, but no change in accel/decel you would have felt your * erse against seatback = climb. Unfortunately it was decent.

There you go.

bubbers44
6th Aug 2011, 01:57
My airline never said pull up to 7,000 FPM climb if I lose my airspeed in the clouds. Something like hold cruise pitch and power.

Of course we already knew this before we got hired having flown several dozen types of aircraft single pilot in most cases and quite a few jets with lots of time.

The new way of training airline pilots in automatic airplanes makes them systems operaters, not real hands on pilots. I think we will see more of these accidents as the old guys retire and the systems operaters take over the cockpit.

L-38
6th Aug 2011, 03:05
"I think we will see more of these accidents as the old guys retire and the systems operaters take over the cockpit."
No doubt "more of these", but also - less of those - . . . for now . . that's progress . . (and I don't like it!).

Graybeard
6th Aug 2011, 03:27
Originally Posted by Graybeard
Birgenair was different, because the lower ranked FO knew what was happening
..........DW: As did the PNF in this case, judging by the CVR.

GB: The FO could have overpowered Capt. by pushing harder on the yoke. Could he have done that with a joystick?

DW: If he'd called "I have control" and pressed the priority button, of course he could have. The issue for the Birgenair F/O, as it was for the AF447 PNF was that he wasn't assured enough of his assessment of the situation to take positive control and hold it.

GB: As for your argument that the 777 backdrive can fail: it's built to the same safety standards as the Cat IIIc autoland, i.e., 10 -(7?) probability of undetected failure.

DW: As are the Airbus systems, so why trust one system and not the other?It's you who previously threw out the probability of a 777 backdrive failure rendering it no better than a joystick.

The 777 backdrive provides continuous feedback to the PNF of the commands by the PF and AP. And it is in the peripheral vision at all times, even while the PNF is attending the ECAM. The PNF doesn't have to focus on the EFIS to interpret the commands.

And you're wrong to equate a high ranking Capt on Birgenair to the AF 447 PNF copilot. The 447 PNF seemed to be less aware of PF actions, because there was no yoke!

MountainBear
6th Aug 2011, 03:46
@DW

but to argue that the stall warning significantly and repeatedly stopped the PF from doing the right thing (nose down) because the warnings were triggered *as a result* of his nose-down input is untrue.

I think we will never know. None of us can get inside the PF's head to know exactly what he was thinking. It's possible that the stall warning had zero influence on his behavior. OTOH, it's possible that it did. I agree with you that the stall warning did not "significantly and repeatedly stop" the PF from doing the right thing. OTOH, a more robust design might have been just the little nudge he needed in the right direction. On that point we will never know.

jcjeant
6th Aug 2011, 04:17
Hi,

I think we will see more of these accidents as the old guys retire and the systems operaters take over the cockpit. That's possible
What we know for sure .. is that possible that a high technology plane with the latest flight security systems (redundancy .. protections and limitations ... or like some tell ... fool proof) can go from a eventless flight at 35000 feet .. to the ground in 4 minutes .. just because a indication speed lost forced the pilots ( from a major European airline) to manually fly the plane (even with some aids still working)
That's a "premiere" .. and hopefully not the first of a serie ......

alanp
6th Aug 2011, 05:30
Ultimately, it's all irrelevant.

Airbus,and I suspect Boeing, never expected a pilot to put their plane through this.

The long chain, and Swiss chess, started when this pilot was accepted for flight training.

grimmrad
6th Aug 2011, 05:56
@jcjeant

Medical license.. Try to get a license in NyC. They stop short of asking for your kindergarten reports... Especially if you are FMG you need to provide everything and thy contact your Med School to see if it is legit. But I agree, it can happen in our field too...

jcjeant
6th Aug 2011, 06:09
The long chain, and Swiss chess, started when this pilot was accepted for flight training. And even more drastically .. it begins with his birth ... :eek:
The problem is to detect incapacities (if any) by testing .. or more hypothetically .. at birth :confused:

Wannabe Flyer
6th Aug 2011, 08:34
t least ....
At the speed with which they came down .. they would certainly have some effect at the eardrums due to pressure difference ... (hurt feeling)
Even at reasonable rate of descent you feel this (even if cabin pressurised)

In a media report / briefing there was some talk of the passengers knowing/not knowing of the decent over 4 minutes.. I was unable to find any reference to this comment in print anywhere. Could someone point me in that direction. Additional query would be if the sensation of rocking and falling would feel like bad turbulence or would there have been a sensation of weightlessness / Incapacitation etc.

Not a lawyer!!!

RWA
6th Aug 2011, 14:07
Quoting Neptunus Rex:-


Not quite. Manual pitch trim should have been available in both cases.


I don't think so, Neptunus. Don't forget, 'autotrim' was still operating; and I don't think Airbus pilots have the option of turning it off? So if they'd wound the trimwheel forward to reduce the huge (13-degree) 'up' angle the systems appear to have imposed, the autotrim would presumably just have wound it back to 'Square Thirteen' again?

morphmorph
6th Aug 2011, 14:57
Quoting RWA:

...if they'd wound the trimwheel forward to reduce the huge (13-degree) 'up' angle the systems appear to have imposed, the autotrim would presumably just have wound it back to 'Square Thirteen' again

The systems only imposed the 13 degree up angle because the pilot asked for it by backwards pressure on the SS that increased the pitch angle to the point where the aircraft stalled - the system was doing exactly what the pilot requested. Even then, if he'd moved the SS forwards again to try to reduce the pitch angle (and consequently the AOA), as you'd expect any pilot to do when in a stall, the system would've moved the THS accordingly.

jcjeant
6th Aug 2011, 15:00
I don't think so, Neptunus. Don't forget, 'autotrim' was still operating; and I don't think Airbus pilots have the option of turning it off? So if they'd wound the trimwheel forward to reduce the huge (13-degree) 'up' angle the systems appear to have imposed, the autotrim would presumably just have wound it back to 'Square Thirteen' again? I don't think so
If pilot had moved the trim .. he take authority over the auto trim and the trim will stay where the pilot put it ... and the trim will not return in primitive position
AFAIK

Remember the Westland Lysander ??
This old plane had already "auto flaps" !
They deployed or retracted regarding of the aircraft speed ...
They had a big effect on the flight attitude of the plane (don't forget to trim !!)
If the pilot dont know that .. it was the crash as result .. at landing or take off
If you don't know the plane you fly .. the result can be a catastrophe .. Lysander or A330 .. same results

morphmorph
6th Aug 2011, 15:03
Quote from grimmrad:

Regarding the question about a license... does that mean you can be pilot in a major carrier WITHOUT the license??

No - all of the pilots had licences - the list of qualifications each pilot held is in the BEA report. The captain was asking whether the licence he held "qualified [him] to act as relief" (quote from from the BEA report).

jcjeant
6th Aug 2011, 16:18
No - all of the pilots had licences - the list of qualifications each pilot held is in the BEA report. The captain was asking whether the licence he held "qualified [him] to act as relief" (quote from from the BEA report). Indeed .. and it's a odd question of the captain when replaced in the context :sad:
(this copilot made also with same captain the flight Paris - Rio ... and captain don't know the qualifications of his crew :confused: ... show at least the no professionalism of the guy ... or bad Air France rules )
Go figure the logic .....
By the way .. it's not a part of the CVR transcript ... it's reported by BEA
Waiting for the full CVR transcript ....

Denise Moore
6th Aug 2011, 16:28
OK, I've gone and read details in the Tech Log thread, but there still seem to be some questions the BEA hasn't answered, or hasn't tried to answer. (Or if so, I've missed them.)

Why the initial climb?

As for the pilots not recognizing they were in a stall, I think that is because they knew some instruments were not working --- but did not know which were working --- so they were totally confused about what was true and what wasn't. I know someone said earlier pilots were supposed to know which instruments were fed by what, but that's not the same as knowing in a real life situation which instruments can actually be relied upon. I wonder how many pilots would really know. I don't think any amount of training would solve this problem. Obviously technical solutions are limited. Put an indicator next to the instrument indicating its value is valid or not, then how do you know if that indicator is working correctly!
But I certainly don't see this as pilot error.

From the transcript, the conversation suggests they clearly didn't know the seriousness of their situation.

Why WAS the THS stuck up? Down inputs were recorded or mentioned. The BEA emphasizes the plane was fully functional and responsive, so why was the THS stuck up and remained stuck up?

Mr Optimistic
6th Aug 2011, 16:32
It wasn't stuck up.

TioPablo
6th Aug 2011, 16:40
jcjeant said:
If pilot had moved the trim .. he take authority over the auto trim and the trim will stay where the pilot put it]Well said master! :D

Will edit once more... Reminder: "Speed = Life"... On doubt... Always Speed! Why?
Coz the wings fly... (And speed is AoA, no engines involved).

jcjeant
6th Aug 2011, 16:51
Why WAS the THS stuck up? Down inputs were recorded or mentioned. The BEA emphasizes the plane was fully functional and responsive, so why was the THS stuck up and remained stuck up? Check Technical Log forum
It's explained (many time by takata and some others) with drawings of the system logic and also graphs extracted from BEA report N*3
Make your searches .. be informed.
BTW the THS is not stuck (blocked)

Denise Moore
6th Aug 2011, 17:16
OK, I stand corrected that the THS wasn't "stuck up". I recall a number of posts trying to figure out why it was up, and whether it was stuck, broken, etc. But it seems to have been up (for whatever reason) and stayed up. Has the BEA explained why?

Phantom Driver
6th Aug 2011, 17:17
RWA-

be interesting to know whether Airbus, Air France, or the BEA had warned pilots that this sort of 'impasse' could occur; and indeed had occurred, as far back as Perpignan in 2008? I very much doubt it........Amongst all the hot air generated on this topic, I think your analysis may pretty well hit the nail on the head. Unfortunately, a lot of people may not be seeing things in quite the same light. Quite a few posts ago, I made the comment that a very small pull on the stick at high altitude, if you were heavy and close to max altitude, (should'nt be there in the first place, especially if turbulence is present, as the FCTM clearly states), could put you in stick shaker very quickly, together with a zoom up into "coffin corner" territory, (don' t hear much talk about that phrase these days, do we!)

Combine that startle factor (for the unprepared/untrained) with a full up THS and you can see why a certain element of confusion may have arisen. I think we will eventually find there is more to this than simple pilot error. Not bashing Airbus, (they build great aircraft, and I speak from experience of operating the type as well as Boeing), but nevertheless Toulouse will have some explaining to do here.

Regrettably, over the years, Airbus have usually blamed the pilots in most accidents ("they did not understand the systems"), but then they quietly go ahead and change some bit of software/hardware.

Kalium Chloride
6th Aug 2011, 17:54
But it seems to have been up (for whatever reason) and stayed up. Has the BEA explained why?

The reason is simple. The pilot's nose-down inputs only reduced the elevator deflection a little - the elevator still stayed "up".

He didn't keep the stick forward far enough or long enough to move the elevator back to neutral, and then into the "down" position. The THS would only have started moving "down" again once the elevators were pushed beyond neutral.

The THS behaved exactly as designed.

DozyWannabe
6th Aug 2011, 18:51
Regrettably, over the years, Airbus have usually blamed the pilots in most accidents ("they did not understand the systems"), but then they quietly go ahead and change some bit of software/hardware.

Not wishing to sound facetious, but would you care to provide examples of where this has been the case any later than, say, 1994 (when the death of senior test pilot Nick Warner on a demonstration flight caused them to re-examine their priorites)?

He didn't keep the stick forward far enough or long enough to move the elevator back to neutral, and then into the "down" position.

Neither, importantly, did he exercise the option to re-trim the aircraft manually using the trim wheels, which would have taken significantly less time - presumably because he was not taught how.

jcjeant
6th Aug 2011, 19:20
Hi,

Not wishing to sound facetious, but would you care to provide examples of where this has been the case any later than, say, 1994 (when the death of senior test pilot Nick Warner on a demonstration flight caused them to re-examine their priorites)?

One from head is Mount St Odile (some changes after .. despite pilots made some mistake about descent rate settings if remember well) about interface

cwatters
6th Aug 2011, 19:25
The systems only imposed the 13 degree up angle because the pilot asked for it by backwards pressure on the SS that increased the pitch angle to the point where the aircraft stalled - the system was doing exactly what the pilot requested.

That might be how the system is designed to work but is it how a human "naturally" expects a system to work? Hasn't it been proven over the years that in an emergency we revert to how we expect things to work regardless of how they actually work or how we're trained to use them?

If I turn the thermostat up on my heating system I wouldn't expect the temperature to get hottor and hotter indefinitely.

If I turn the steering wheel of my car I wouldn't expect the turn to get tighter and tighter until the steering rack is on full lock.

Even the accelerator pedal on my car mostly behaves like a speed control rather than an accelerator. Once I have reached the desired speed I don't lift off the pedal to maintain that speed. I have to keep it pressed.

What other familiar systems have a "runaway" behavior like the auto trim?

Rob21
6th Aug 2011, 19:33
One thing that is puzzling me is the speed of PF's hand on his movements aft and forward on the sidestick.
From 02:10:13 to 02:10:16 (only three seconds) he moved his sidestick 9 times. That's three times a second...
And with significant amplitude also.

What was he chasing?

xcitation
6th Aug 2011, 19:36
Why the initial climb?

The answer can be speculated from the BEA report.
When AP disconnected the a/c was pointed down slightly (Pitch=0 deg) and it was descending. Also altimeter might have jumped down a few hundred feet because of impared pitots and air temperature sensors due to a possible ice build up from the strom they were in.
Pilots are trained to maintain altitude in cruise so he correctly pulls the stick back to keep at FL350. It appears he was in a down draft because it took a large stick deflection to maintain altitude for a few seconds. At high altitude and speed his strong stick input has dangerous effects and a stall warning is triggered. He then notices airspeed is broken. We can speculate that he was distracted, took his attention away from altitude and tried to process what was happening. More errors occur further distracting him. Finally the a/c has risen to FL375 before he figures out he has climbed, he had exited the downdraft and had held the nose up attitude.

Climbing the aircraft without adding power results in a drop in speed. Same as a pendulum swing up. Now a/c was in a dangerous high altitude and low speed condition with impared flight controls (ALT LAW).

morphmorph
6th Aug 2011, 19:43
What other familiar systems have a "runaway" behavior like the auto trim?It didn't runaway. The pilot made such high nose-up demands via the SS for such a long time that to satisfy his demands the system gradually trimmed to full nose-up. If he'd relaxed the back pressure for long enough (ie. taken "standard" stall recovery actions) the trim would've moved back towards the nose down position. It just trimmed to try to satisfy what the pilot what was asking of it - a high nose up attitude.

If I turn the thermostat up on my heating system I wouldn't expect the temperature to get hottor and hotter indefinitelyNo, but if you set the thermostat to a temperature that was higher than the heating system could achieve the temperature would rise to that limit. Similarly, the pilot was requesting a nose-up attitude that the aircraft, with it's low speed, couldn't achieve and the trim ended up moving to the nose-up limit.

xcitation
6th Aug 2011, 20:03
puzzling...
One thing that is puzzling me is the speed of PF's hand on his movements aft and forward on the sidestick.
From 02:10:13 to 02:10:16 (only three seconds) he moved his sidestick 9 times. That's three times a second...
And with significant amplitude also.

What was he chasing?


Agreed. Look at the accelerations too.
Looks to me like he was over sticking then having to correct for each input.
Instead i imagine he should have used smooth gentle deflections.
Ever seen a nervous person drive a car like this? Constantly twitching the wheel having to correct over steer in each direction. A smooth small input is all that is required. I have also seen people use accelerator and brake in the same way, constantly pressing one peddle then the other. Instead of just calmly pressing accelerator to desired speed. You are pulled back and forwards in your seat. Can't say i've seen that behaviour much in pilots.
Totally speculative - is this consistent with anxious/un-trained behaviour from the onset.

MD83FO
6th Aug 2011, 20:04
In alternate law we are still in load factor demand correct?

Lemain
6th Aug 2011, 20:20
Can't say i've seen that behaviour much in pilots.Could be a passenger was flying it while waiting for the toilet? Or could be an instrumentation or recording error ;)

Rob21
6th Aug 2011, 20:57
xcitation, it looks to me that he is "chasing" a flickering PFD.

It was an attitude indicator, because he is correcting roll also.

But anyway, at least to my knowledge, the normal is to be "quick" on ailerons and "easy" on elevators.

The graphics show the opposite.

xcitation
6th Aug 2011, 21:24
In alternate law we are still in load factor demand correct?

According to the docs ALT1 / ALT2 have Load Factor.

DozyWannabe
6th Aug 2011, 22:16
One from head is Mount St Odile (some changes after .. despite pilots made some mistake about descent rate settings if remember well) about interface

That was in 1992 (2 years before the cutoff date I specified), and interestingly was the occasion on which the BEA invited the NTSB over to perform a co-operative investigation in order to prove they weren't trying t oprotect Air Inter or Airbus.

(The fact that Air Inter specifically ordered A320s with GPWS deleted didn't help in that case either)

bubbers44
6th Aug 2011, 23:19
One thing that is puzzling me is the speed of PF's hand on his movements aft and forward on the sidestick.
From 02:10:13 to 02:10:16 (only three seconds) he moved his sidestick 9 times. That's three times a second...
And with significant amplitude also.

What was he chasing?

__

I've flown with a few FO's that did that all the time hand flying. They have plenty of experience but don't seem to trust themselves hand flying so keep doing PIO's to touchdown. You would think some hands on flying would stop this but a lot of airlines discourage hand flying these days. The PF in the AF447 crash didn't seem to have a clue when the automatics failed. They need to look at the Bob Hoover you tube flick where he pours an iced tea pitcher into a glass while inverted in a roll in a Shrike on page 83 of the tech forum. I know Bob and he knows how to fly an airplane. He will be at Reno at the air races in mid Sept.But he has retired from demo flying.

Rananim
7th Aug 2011, 00:48
That was in 1992 (2 years before the cutoff date I specified),

Dozy
So what are you implying?That there was conspiracy to deceive and obfuscate prior 1994 but everything 's been above board since?

Would you say there are any latent dangers in this autotrim design in abnormal ops or that the pilots always instantly and intuitively recognize the transition from auto to manual?

Would you say that the stall inhibit below 60 is excusable in design terms as its outside the realms of probability?

Would you say that the SS is ideal in a multi crew environment especially when considering scenarios where stick input must be timely and CORRECT(stall/x-wind/sev turb etc)?They have the stick in fighters but thats one man.Why did AIrbus employ it in commercial airliners?To be NEW?You seem to be an avid Airbus apologist so I'd like to know.

Do you have an opinion on why BEA withdrew the stall logic recommendation(factors affecting safety can and must be included in initial/interim reports but maybe theres a valid reason)?

Do you have an opinion on why no mention was made of the Captain's decision to leave the cockpit even though he now appears to have known that weather was up ahead?

DozyWannabe
7th Aug 2011, 01:22
Dozy
So what are you implying?That there was conspiracy to deceive and obfuscate prior 1994 but everything 's been above board since?

Hi Rananim, long time no see... :)

Not at all. They were overconfident in the abilites of their systems prior to 1994, that's for certain - and as such predisposed to put things down to pilot error when interface issues should have been looked at (the dual-mode Vertical Speed and Flight Path Angle in the Honeywell FMC being a major case in point, but the same computers were used in other manufacturer's aircraft). Airbus weren't alone in trying to point the finger at pilots in the '90s - Aircraft manufacturers are billion-dollar corporations open to massive liabilities claims and as such their legal departments will tend to demand it - look at how Boeing tried to pass the 737 rudder PCU issue off as pilot error until the NTSB had the "eureka" moment and tried a thermal shock test.

Would you say there are any latent dangers in this autotrim design in abnormal ops or that the pilots always instantly and intuitively recognize the transition from auto to manual?

My honest answer is I don't know, but the fact is that the inputs made to the system were way in excess of any input that should have been applied at cruise level. As (I think) PJ2 says, manually controlling the Airbus via sidestick at altitude requires light thumb pressure in pitch, and gentle lateral movements. This guy wasn't taught how to handle the thing, so he's bashing it on the stops.

Would you say that the stall inhibit below 60 is excusable in design terms as its outside the realms of probability?

I wouldn't say anything other than that design tends to happen at the limits of what is known. I definitely think the logic needs looking at, but I find it difficult to be too hard on the aircraft and systems designers for not contemplating what would happen if the aircraft lost all speed data and ended up in a mushy stall due to overcontrolling. For all we know the stall warning on other modern airliners has similar inhibit modes, and I'm sure Airbus will share whatever information they have in that regard.

Would you say that the SS is ideal in a multi crew environment especially when considering scenarios where stick input must be timely and CORRECT(stall/x-wind/sev turb etc)?They have the stick in fighters but thats one man.Why did AIrbus employ it in commercial airliners?To be NEW?You seem to be an avid Airbus apologist so I'd like to know.

For a start, I am an apologist for no-one, see my earlier post for further details there (should only be a page or two back [EDIT - http://www.pprune.org/rumours-news/447730-af447-wreckage-found-133.html#post6622053]). Secondly, if you're going to start an airliner design from a fresh sheet, why not? Yokes can be a pain in the ar*e, and have noticeably been used as a crutch in certain situations (some of which happened after the A320 was well off the drawing board) when they had been effectively rendered completely useless. Sidesticks are smaller, lighter, de-clutter the flight-deck, allow more freedom of movement and the lack of backdrive makes the system less complex (technophobes don't even want to *think* about the numbers of lines of code required to make the B777 yoke behave like the old-school ones). It would also appear that the majority of people on here who have an issue with the sidestick have never used one. Neil Armstrong certainly didn't have a problem with them...

Do you have an opinion on why BEA withdrew the stall logic recommendation(factors affecting safety can and must be included in initial/interim reports but maybe theres a valid reason)?

Presumably to clarify what the situation regarding stall warning actually is. This is an interim report after all, so let's wait and see what the final report says. I have a strong suspicion that stall warning logic is a complex beast that's going to need to be looked into by all manufacturers. Stall warnings and pilot's responses to them have been a prickly issue since at least 1972 and the BEA548 Trident accident.

Do you have an opinion on why no mention was made of the Captain's decision to leave the cockpit even though he now appears to have known that weather was up ahead?

Not at all, other than from a layman's perspective (in airline pilot terms) it appears that AF has a few CRM issues it needs to address if it hasn't already done so, but primarily, I believe that placing two F/Os in the flight deck - in the ITCZ at night notwithstanding - when neither of them has had any high-altitude manual flight training is frankly inexcusable.

jcjeant
7th Aug 2011, 01:26
Do you have an opinion on why BEA withdrew the stall logic recommendation(factors affecting safety can and must be included in initial/interim reports but maybe theres a valid reason)?From the BEA site (french)
communiqué 3 août 2011 (http://www.bea.aero/fr/enquetes/vol.af.447/com03aout2011.fr.php)

Google site translation:
Google Vertaling (http://translate.google.be/translate?u=http%3A%2F%2Fwww.bea.aero%2Ffr%2Fenquetes%2Fvol. af.447%2Fcom03aout2011.fr.php&sl=fr&tl=en&hl=&ie=UTF-8)

Transcrypt of press meeting is also now available (english)
Transcript de la conférence de presse du 29 juillet 2011 (http://www.bea.aero/fr/enquetes/vol.af.447/transcript29juillet2011.en.php)

bubbers44
7th Aug 2011, 02:20
If the PNF had a yoke in front of him flailing all over the place mostly in his lap don't you think he would have responded and put it where it was required to be for the no airspeed situation? I know the yoke costs money and weight but isn't it a wonderful way to see what your fellow pilot is doing? Maybe Airbus should put yokes back in their aircraft.

What the lawyers lawsuits are going to cost them negates all the years of SS controls to reduce weight and cost.

This could happen again.

Recovering a Cessna 152 from a students stall is easy with dual yokes. It would be more problematic with a side stick of Airbus design.

DozyWannabe
7th Aug 2011, 02:27
Recovering a Cessna 152 from a students stall is easy with dual yokes. It would be more problematic with a side stick of Airbus design.

That's why training aircraft don't have non-interconnected sidesticks. :)

One would hope that by the time someone has ended up in the flight deck of an airliner that they would have the requisite training for controlling the aircraft at that level (in terms of ability and altitude!). Airbus certainly haven't condoned pilots being certified without that training, but it would appear Air France let it happen anyway. Why the desire to crucify Airbus, when Air France seem to be the problem here?

Airbus's ace-up-the-sleeve has always been the ease of type conversion between their narrowbody short-haul types and their widebody long-haul types - weight saving was simply an added bonus. The advantages of starting from a clean sheet in that manner seemed at the time to have provoked a severe case of sour grapes from the other side of the Atlantic, which at one point considered the monopoly of western airliner design it's god-given right. The early years of competition between the two were bitter, but it seems to have resolved into a more friendly rivalry these days - unfortunately some seem to not to want to let it go.

bubbers44
7th Aug 2011, 02:37
The comment about no high altitude training hand flying being inexcusable is naive. It was the norm when we came to the airlines. We were expected to know it. We were dispatched at high altitude with no autopilot with FAA blessings. The problem with inexperienced pilots going through airline training programs is they don't have the money or time to spoon feed new hires. They start their job barely qualified in normal conditions. You can't expect much performance in the AF 447 crash and you didn't. That is the new culture.

TioPablo
7th Aug 2011, 03:17
The problem with inexperienced pilots going through airline training programs is they don't have the money or time to spoon feed new hires. They start their job barely qualified in normal conditions. You can't expect much performance in the AF 447 crash and you didn't. That is the new culture. I have to enter at least 10 characters... But this was all I wanted to say :ok:

DozyWannabe
7th Aug 2011, 03:20
Then would you not agree that the culture needs changing?

Look, I may for various reasons have abandoned any attempt to fly professionally early in life - but I'd have thought that if it's in your blood you want to do it to the best of your ability. To reduce it to "just another job" is ridiculous. The airlines expect you to handle these things manually at cruise altitude without training when things go pear shaped? I suspect there'd be an uproar of sizeable proportions if it ever got out that that was the norm...

takata
7th Aug 2011, 03:43
Hi Bubbers44,

If the PNF had a yoke in front of him flailing all over the place mostly in his lap don't you think he would have responded and put it where it was required to be for the no airspeed situation? I know the yoke costs money and weight but isn't it a wonderful way to see what your fellow pilot is doing? Maybe Airbus should put yokes back in their aircraft.

What the lawyers lawsuits are going to cost them negates all the years of SS controls to reduce weight and cost.

This could happen again.
After the plastic vertical stabilizer snapping off, the crazy computer automatic dive, the flat spin caused by too far aft CG, the total loss of elevator control due to THS autotrimming, the complete loss of artificial horizons (meaning a quadruple failure of inertial systems), the supposed lack of alpha indicators (which exist but that no company really care to add on pannels) or control surface feedback, etc. theories... we are back, now to the so flawed sidesticks that can not allow any cross control check of imputs...

Actually, this feature exists on all Airbus aircraft, but it's not displayed after take-off. Then, one should ask Why it is like that?
In fact, because nobody using those aircraft seems to be very concerned about such an "obvious" need or it would have been made possible from two decades. Nonetheless, it could be very easy (and cheap) to add it, without changing anything to the actual stick system, via a stick pushbutton commanding to display this function (see below) during whatever phase of the flight.

Going on lawsuits against Airbus on such a case would be a non-winning game. Nothing is showing that it was a factor at all, neither that doing otherwise is better. It is obvious that the PNF complained about PF initial imputs almost immediately: he saw them and was able to take over at any point (including by blocking PF further actions) but he refrained from doing so.

Function displaying sidestick imputs:
http://takata1940.free.fr/sidestick.jpg
(http://takata1940.free.fr/sidestick.jpg)

oldchina
7th Aug 2011, 07:34
When they started to design the 777 (and that's a long time ago) Boeing consulted pilots from around the world. Their preference was clearly in favour of the sidestick.

Not wishing to be seen to follow Airbus, Boeing disregarded this opinion.

RWA
7th Aug 2011, 07:37
Quoting Sidestick:-


Nothing is showing that it was a factor at all, neither that doing otherwise is better. It is obvious that the PNF complained about PF initial imputs almost immediately: he saw them and was able to take over at any point (including by blocking PF further actions) but he refrained from doing so.



Sidestick, I don't know everything about the Airbus displays, but as I understand it the PNF would normally have been able to monitor the control movements of the PF (in the captain's seat) from the Flight Director; but that this depends on the availability of some 'crosshairs'? If you refer to the FDR/CVR transcript (Page 86 onwards) you'll find that the FDs were cutting in and out at intervals throughout the descent; and in the body of the report the BEA says specifically that the crosshairs were cutting in and out even when the FDs were working in other respects? So I for one am none too sure that the PNF had access to the information he needed?

Oddly enough, the BEA has 'covered itself' (in what is only yet another 'interim' report) on this aspect; saying that finding out what information was actually available to the pilots at any particular time will need 'ongoing analyses':-


"Page 481.16.7 - Other on-going analyses - At this stage in the investigation, other analyses are still in progress. Notable amongst these are the attempts to recalculate the airspeed from ADR 2 in order to determine what was displayed on the PF’s PFD and to be able to work out what instructions were displayed by the flight directors’ crossbars. The airplane’s movements in three axes will also be simulated to supplement the longitudinal analysis already performed and to quantify the turbulence experienced by the aircraft."


They also put in some stuff that just about sums up what I for one currently suspect turned an upset into a crash. We all know that such accidents almost never have a single cause: and also that the thing that started off the whole event was the sub-standard pitot tubes (which could and should, IMO, have been replaced months previously). My own view, on present evidence, was that the next most important cause was the inadequate stall warnings; that they tend to communicate 'approach to a stall' and don't 'change their tune' if the aeroplane HAS in fact stalled. And also 'shut up' if the ASI drops below a given speed. Not getting at Airbus specifically on this, I wouldn't be at all surprised if Boeing's stall warnings work the same way.


"Until the end of the flight, the angle of attack values became successively valid and invalid. Each time that at least one value became valid, the stall warning triggered, and each time that the angles of attack were invalid, the warning stopped. Several nose-up inputs caused a decrease in the pitch attitude and in the angle of attack whose values then became valid, so that a strong nose-down input led to the reactivation of the stall warning. It appears that the pilots then reacted by a nose-up input, whose consequences were an increase in the angle of attack, a decrease in measured speeds and, consequently, the cessation of the stall warning. Until the end of the flight, no valid angle of attack value was lower than 35°."

So whenever either pilot applied nosedown stick, the alarms told him that he was, to all intents and purposes, 'making things worse'?

All in all, my conclusion is that it's surely way too early to blame the pilots 100% for this accident?

BOAC
7th Aug 2011, 08:08
RWA - I think we are pretty well convinced by the AB 'knowers' that there is no way PNF would know what PF was doing with the SS when airborne except by a/c manoeuvre. I also believe that the failure of the stall warning system to perform adequately, while a hugely significant factor, is overshadowed by the initial and so far unexplained and 'un-noticed' pull-up to above safe altitude. Once there the dice was indeed heavily loaded.

If what Bubbers says about 3 pitch/roll SS movements a SECOND..................!?? - that is either a fault in the system or one of the most bizarre episodes I have seen of 'stick thrashing' and AF need urgently to review the 'pilots' in their fleets. Was he simply 'chasing' a wild FD?

CONF iture
7th Aug 2011, 08:43
Sidestick, I don't know everything about the Airbus displays, but as I understand it the PNF would normally have been able to monitor the control movements of the PF (in the captain's seat) from the Flight Director
No.

Actually, this feature exists on all Airbus aircraft, but it's not displayed after take-off. Then, one should ask Why it is like that?
In fact, because nobody using those aircraft seems to be very concerned about such an "obvious" need or it would have been made possible from two decades. Nonetheless, it could be very easy (and cheap) to add it, without changing anything to the actual stick system, via a stick pushbutton commanding to display this function (see below) during whatever phase of the flight.
takata, I would be curious to know if you are actually one or more of the following :

FBW Airbus pilot
Multi crew pilot
pilot

larssnowpharter
7th Aug 2011, 10:38
I also believe that the failure of the stall warning system to perform adequately, while a hugely significant factor, is overshadowed by the initial and so far unexplained and 'un-noticed' pull-up to above safe altitude. Once there the dice was indeed heavily loaded.

My reading is that the stall warning system performed exactly as designed and accepted by FAA, EASA and others.

Graybeard
7th Aug 2011, 11:14
I've seen that so many times on these pages in defense of AB, in effort to end a line of thinking. How about considering the design is just plain defective?

How much of the PNF attention was on the ECAM and not on the PF joystick actions? In a yoke airplane, PNF would have been aware of PF actions at all times. Same goes for stationary throttles.

Mimpe
7th Aug 2011, 12:04
FAA data cited in Mitchell and Revans (2004) AvSpace&EnvMedicine

Mitchell cites the risk of pilot error inducing fatal accidents commercial RTP flight by age is lowest age 50-54 years old.
Taken as an index of one, the relative risk of a 40 year old commercial pilot is 1.25, and a multiplication of the risk by 2.5 for pilots under 30. This explains the intuitively correct CRM call by Sullenberger for "my aircraft".
In a situation loaded with risk for aircraft upset, the most experienced pilot would be , according to the accident figures, by far the superior. Sorry all you young atpls...you'll be closer to magic in your late 40' s.Accident rates for pilots at retirement age are also significantly lower than the 30's and under.Interestingly,if one includes back into the stats all those older commercial pilots who have lost their medical clearance due to risk of sudden cardiac death, the statistical overall rate of pilot error accident risks improves dramatically

Froom et al (1988) describe an ever greater jump in risk (by a factor of ten) between 30 year old pilots and their 10 year younger colleagues in the miitary aviation setting.
The situation also reminds me of the now famous "Rumsfeldts", where there is alot of unknown knowns, and unknown unknowns ...the worst place to be in any aircraft.

The AF 447 situation strikes me as one in which the incipient risks required the most experienced hand flyer right from the word go...no time for liberte,egalite,fraternite.....

if you get my drift.

takata
7th Aug 2011, 12:08
@ CONF iture
Well who cares what I'm doing for a leaving. I know that the purpose of such function is not aimed at controling PF imputs. But, as both stick imputs are already linked to PFDs, it would be no big deal, if such was really asked and needed by customers, to modify it for cross checking pilot imputs (and I seem to remember that we already had such a discussion about two years ago).
Even adding some feedback thru electrical commands would not add tons of hardware (weight) nor tremendeous development costs to the manufacturer. The very same could be say about "non-moving" lever thrust, silent autotrim, etc.

On the other hand, you just hate this brand, whatever their reasons being to do it like that. I can't remember a single feature you actually liked about an aircraft you are supposed to fly. On my side, I'd like to know why is your grief so deep? Personnal vendetta?

takata
7th Aug 2011, 12:30
Hi Greybeard,
How much of the PNF attention was on the ECAM and not on the PF joystick actions?
It seems that there was not a single ECAM TB sequence popping up before 2 minutes after UAS, hence 1 minute+ into the full stall developement (0212+); the only one showing up, quite late, was ADR DISAGREE; there is barely no call about a procedure performed by him, either...

BluJet
7th Aug 2011, 12:50
Hi takata,
no big deal but just to make it clear:

Sidestick
Hi Bubbers44,
Quote:
Originally Posted by Blujet
The post you are referring to was not issued by myself.

Thank you for your valuable infos on the VSI!! I checked 34-14-00ff but somehow missed this.

DC-ATE
7th Aug 2011, 13:21
Graybeard -
I've seen that so many times on these pages in defense of AB, in effort to end a line of thinking. How about considering the design is just plain defective?
How much of the PNF attention was on the ECAM and not on the PF joystick actions? In a yoke airplane, PNF would have been aware of PF actions at all times. Same goes for stationary throttles.

AMEN to ALL of that, Brother. But, you'll NEVER get the AB supporters to agree, unfortunately.

RWA
7th Aug 2011, 13:27
Quoting bubbers44:-

"One thing that is puzzling me is the speed of PF's hand on his movements aft and forward on the sidestick.
From 02:10:13 to 02:10:16 (only three seconds) he moved his sidestick 9 times. That's three times a second..."


I think this may well be a matter of 'super-sensitive' recording, rather than anything more sinister. If you ignore the 'snaking lines,' and just count the basic 'ups and downs,' rather than the 'zigzags,' there appear to have been only about four of each in the period referred to. And we have to remember that the PF had just taken control after the autos signed off - according to the Report, his main concern at that time was to correct a tendency to roll. He'd have been mainly concerned with moving the stick sideways, not forward or back; if he'd moved it even slightly forward or back during the sideways movements (and assuming, as one has to, that the systems were probably recording in fractions of a second) it was probably 'no big deal.'

Looking again at Page 111, though, I noticed another thing. Assuming that I've interpreted the graphs correctly, while the THS was still moving towards 'full-up,' the PF applied full nosedown for quite a long period; probably because, as the report says, he was (correctly) countering the zoom climb. But the THS just continued on it's 'merry' way to full up.

What's more, if you look lower down, the Angle of Attack graph starts increasing at exactly the same time that the THS starts moving, at what looks like an exactly-equal angle (though opposite on the graph). And reaches its highest angle just as the THS arrives at 'full up'?

So (assuming I've read the graphs right) why didn't the THS react to the PF's apparently 'solid' nosedown input and 'get sensible'?

Karsten99
7th Aug 2011, 13:59
Hello Mimpe
The AF 447 situation strikes me as one in which the incipient risks required the most experienced hand flyer right from the word go...no time for liberte,egalite,fraternite.....


Your numbers are very interesting.
But is it really a question of experience or is there more about this?
If its is only experience than this should be a constant about the history of aviation.

If its not a constant than there might be other factors like for example changed traning involved.

DozyWannabe
7th Aug 2011, 15:05
I've seen that so many times on these pages in defense of AB, in effort to end a line of thinking. How about considering the design is just plain defective?

The "Airplane with HAL" :

Number of A330s built : 802
Number of A330 hull losses : 6

Percentage lost : 0.75%

The "Old-fashioned pilot's aircraft" :

Number of DC-10s built : 386
Number of DC-10 hull losses : 31

Percentage lost : 8%

You were saying?

Petercwelch
7th Aug 2011, 15:16
Do most of you agree that a boeing aircraft faced with the same conditions and failure would have clearly handled the problem and not ended up in the drink?

DC-ATE
7th Aug 2011, 15:28
YES.....Douglas also.

DozyWannabe
7th Aug 2011, 15:32
@Petercwelch - I don't think that's a fair question. Going purely on statistics there have been two Boeing airliners (both 757s) that have ended up in the drink due to unreliable air data causing pilots to mishandle the aircraft, whereas to date it has only happened with one Airbus.

The issue at hand is whether the cockpit environment on older airliners is more conducive to help the pilots understand the problem (overcontrol -> stall -> loss of control). Some on here are adamant that it would be the case, others are not so sure.

3 pilots, 6 opinions and all that... ;)

@DC-ATE - you could crash a DC-8 on approach by pulling a single lever too early ("It is forbidden to crash this airplane"). You could disable the takeoff trim warning on a DC-9 just by pulling a single circuit breaker that connected to a bunch of other systems, some of which were on the MEL. You could crash a DC-10 by not closing the door properly, and the door latch design itself would have caused Rube Goldberg (or Heath Robinson to us Brits) to wince. In the latter case, Douglas effectively bribed the FAA to not release that information while promising to fix the problem - they didn't fix it properly and nearly three hundred people died. Don't talk to me about Long Beach's supposedly superior engineering skills - they were riding the coattails of the DC-3's popularity and producing shoddy designs right up until they closed their doors.

DC-ATE
7th Aug 2011, 15:54
Well.....when I wrote Douglas, I guess I shudda specified DC-8. Never flew the other ones. Didn't like 'em. As to that "lever", it only happened once [which is enough] then everyone knew 'bout it and it never happened again. Give me a yoke any day, not one of these stupid SS controlers.

morphmorph
7th Aug 2011, 16:32
But, you'll NEVER get the AB supporters to agree, unfortunatelyIt isn't about "AB supporters" or AB detractors - accident investigation should be an objective examination of the facts leading to a determination of the probable cause and making recommendations to improve what went wrong, no matter who manufactured the aircaft, who owned it, and who was flying it.

takata
7th Aug 2011, 16:32
Hi BluJet,
The post you are referring to was not issued by myself.
Arf!
Sorry for that! (I'm getting lazy at recycling old notepad templates)

alf5071h
7th Aug 2011, 16:57
Petercwelch, #2712,
Your question assumes that the manufacturing design was the primary (dominant) or the only cause. It’s generally accepted that accidents are the culmination of many factors, requiring the interaction of significant issues.
Accidents arise from the unforeseen and often unforeseeable concatenation (linking) of diverse events, each one necessary, but singularly insufficient. J Reason.

A significant issue in this accident appears to be human behaviour; the crew’s perception and choice of action. Unfortunately we are unable to establish all of the facts of these matters. In our speculation we are exposed to hindsight bias due to the nature and timing of available information.

Some may argue that the Airbus FBW control system design degrades awareness, but the system is used without mishap in everyday operations by Airbus crews.
Have they adapted, have alternative control skills, or use other aspects for awareness? What are these features; were they absent in this accident or did the crew fail to use them? These have yet to be established.
The design of the stall warning system might be similarly cited, but other aircraft, although not engineered in the same way, have similar systems and meet the same requirements – including preventing unwanted warnings in other areas of the flight envelope, e.g. use system inhibits.

A more plausible view is that none of the crew identified the stall condition; again an aspect of awareness, and also, if the all speed displays are unavailable, an aspect which does not appear to differ with aircraft type.
If as suggested in the report, the PF had a mental goal of achieving an erroneous pitch attitude – that required for flight without airspeed, but which did not apply at high altitude, this also is invariant with aircraft type.
Conversely it is arguable that the resultant stall condition could have been recovered with a stick-push system, as fitted to many aircraft – noting that a controlled flight manoeuvre into the stall (as with AF447) would provide similar trim conditions irrespective of aircraft type. But again we can only speculate how the crew might have reacted to a stick push with regard to their mental model of the situation. We would hope that a forced stall recovery would ‘jolt’ the mindset, but evidence from other accidents (Colgan) suggests otherwise.

Many safety activities depend on asking questions, but the key issue is to ask the right question because in most cases, then the answer is obvious.
This accident has posed many questions and the industry is having difficulty in identifying ‘the right one’. This will not involve the aircraft type alone, but include the limits of human performance, the operational situation, organisation, and the system at larger in which we live; it will involve what we do and encounter every day, and how we do it.

Jazz Hands
7th Aug 2011, 17:18
while the THS was still moving towards 'full-up,' the PF applied full nosedown for quite a long period; probably because, as the report says, he was (correctly) countering the zoom climb. But the THS just continued on it's 'merry' way to full up


Where do you see any evidence of "full nosedown for quite a long period"?

During the transition of the THS there are only a few intermittent nose-down spikes - the trace below the zero line means the stick was held back, pitching up.

Check the elevator trace on the same page: once the THS is on its "merry way to full up", at no time is the elevator pushed to pitch down. Not even close. The best it gets is about 15deg, pitch up. No wonder the THS never came back.

xcitation
7th Aug 2011, 18:39
Be very careful with stats especially when comparing apples with oranges.
How many total flight hours were they flown?
What type of flights (any military to theater of operations).
Have you corrected for tech advances - it would be better picking a contemporary of A330.
That said I do believe airbus are in general very safe, sadly the same cannot be said of humans.


The "Airplane with HAL" :

Number of A330s built : 802
Number of A330 hull losses : 6

Percentage lost : 0.75%

The "Old-fashioned pilot's aircraft" :

Number of DC-10s built : 386
Number of DC-10 hull losses : 31

Percentage lost : 8%

ap08
7th Aug 2011, 18:55
Have you corrected for tech advances - it would be better picking a contemporary of A330.
The correct comparison is A330 vs. B777. All the numbers are from Wikipedia, I have not checked them myself but expect them to be reasonably correct.

A330:
Produced 1993–present
Number built 796 as of 30 June 2011
As of June 2011, the Airbus A330 had been involved in thirteen major incidents, including six confirmed hull-loss accidents and two hijackings, for a total of 338 fatalities.

B777:
Produced 1993–present
Number built 923 as of March 2011
As of April 2011, the 777 has been in seven incidents, including one hull-loss accident, and two hijackings, with no fatalities among the passengers or crew.

Any questions still remaining?

Lyman
7th Aug 2011, 19:15
I think there is very little to be gained by such "comparisons". "margin for Error" has more to say than raw numbers, and it always gets doen to subjective hoorah. both capable ships, and 447 has more to teach us that is real, and precious than fanbase. In a wide field of Gold, the nuggets are gathered early, and eventually, the safety is found in mining.

Phantom Driver
7th Aug 2011, 19:30
Dozy;

Not wishing to sound facetious, but would you care to provide examples of where this has been the case any later than, say, 1994 (when the death of senior test pilot Nick Warner on a demonstration flight caused them to re-examine their priorites)?


Sadly unfortunate the example you quote, because it should be a warning to us all. This happened to a very experienced test pilot, at the end of a very busy day. Basic mistakes were made; if it could catch him out, then God help the rest of us. (Don't have the link to the report, but am sure somebody will provide it).

Re; software/hardware anomalies, a few come to mind-(Indian Airlines A320 open descent into ground at (Bangalore); Air Inter A 320 VS/FPA confusion and subsequent descent into ground -already mentioned;(Austria?); Air France A320 low flypast into trees (Paris?); Air Transat 330 fuel leak/crossfeed mishandling anomaly with glide landing into (Azores).

Don't get me wrong; as stated earlier, I am not bashing Airbus; some of these accidents were in the early days of FBW of which Airbus were the pioneers, and good on them. They are truly innovators. But there is no denying that their systems are not easy to understand, and they did make changes after each of these accidents. But then so did Boeing, and they have been in the business a lot longer.

DozyWannabe
7th Aug 2011, 20:14
@xcitation : I'm stepping back for a bit, but quickly in answer to your question - I'm well aware of "lies, damned lies and statistics", and was just trying to illustrate the point that "the good old days" weren't all that good in some respects

@ap07, I'm not interested in Airbus vs. Boeing discussions - I was simply trying to prove the adage that things have gotten safer thanks to advances made by Airbus, Boeing and *all* manufacturers. Although it's worth noting that of the six A330 hull losses, 2 were due to military action and one was due to a cargo-handling accident. Of the three that were related to flight, one was the infamous test flight, another was the Libyan A330 which so far has no technical cause and the third is AF447.

In any case these statistics are too small to make a valid comparision, mercifully.

@Phantom Driver, the Indian incident, Air Inter and Nick Warner's A330 crash were largely put down to mode confusion, which has since been rectified. Air Transat was down to a maintenance issue IIRC and Habsheim (the A320 lumberjack) is a whole other story, which largely comes down to atrocious preparation on the part of AF, followed by a sequence of bad judgement calls made by the captain. Of these, only Air Transat happened after 1994.

@SLFinAZ below : How have "'A' ... also single handedly pushed the average pilot skill level significantly lower"? I'm all ears. Glass cockpits and full-featured FMS autopilots were pioneered by the A300, but enthusiastically picked up by Boeing with the 757 and 767, and Douglas with the MD-11. "What's it doing now?" has never related to FBW, but to the FMS/FMC/autopilot (call it what you will), which were well-established for more than a decade before the A320 first flew. And as for in-flight hull-loss stats, A330 vs B777 is currently 3:1 (not 0, as you stated), but again these numbers are too small to make a statistical comparison.

SLFinAZ
7th Aug 2011, 20:40
Actually I think that "A vs B" is still not only a very valid question but lies at the heart of the matter.

From my perspective at this point "A" is a safer airplane in the hands of a less qualified pilot. I do not believe that "B" has any inherent advantage with a truly qualified aviator at the controls ("Skullyish")....with the caviat that even with a very seasoned pilot with an above average professional level understanding of the FBW system it is possible for him to have a "what is it doing now" moment.

The real issue is that while "A" has without a doubt single handedly pushed the envelope of what is technologically possible...they have also single handedly pushed the average pilot skill level significantly lower. Regardless of the number of representative hull losses (which could be much worse for the 320/330) {vs 777} the reality is that its B = 0 and A = to many.

What AF447 has made abundantly clear is training/CRM standards (in at least one major carrier) have degraded to a point where if the "system" can't save the plane we have no assurance the pilot will be able to. At the end of the day this crash will boil down to 100% pilot error IMO.

takata
7th Aug 2011, 20:49
Any questions still remaining?
Yes please, can you list those 6 hull losses?

dlcmdrx
7th Aug 2011, 21:05
Stop putting aeroperu and birgenair as examples of anything.
They have no comParison whatsoever to af447 and if they crashed was to reasons totally unrelated to the systems of the planes.

Its very clear the bea and airbus want to send the same message regarding af447, the thing is that is not at all clear.

Jazz Hands
7th Aug 2011, 21:10
Yes please, can you list those 6 hull losses?


Other than the test-flight at Toulouse, two Sri Lankan A330s were shot up at Colombo airport, a Malaysian A330 was written off by a chemical spill, and the loss of AF447 and Afriqiyah 771 makes six.

WFLineage1000
7th Aug 2011, 21:56
...{vs 777} the reality is that its B = 0...
Well, as mentioned before, B=1 ;)

cwatters
7th Aug 2011, 22:11
Several nose-up inputs caused a decrease in the pitch attitude and in the angle of attack

I wonder if the reverse was also true?

dogle
7th Aug 2011, 22:39
This discussion has been largely focussed on the central and tragic sustained pitch-up; may I request attention to a possible clue which not all have picked up? Please take another look at the roll axis traces (bottom of pp 29, 30 of report 3). (I am grateful to xcitation et al. for their posts yesterday which made me revisit in more detail my bad gut feelings on first viewing these traces).

1. I'd expect anyone having the aircraft unexpectedly dumped in his lap on AP disconnect to take a few moments to 'get hold of her'. It took the PF ~ 35 seconds to control the roll, and in that period I see what looks to me like overcontol and PIO; the oscillations are too regular for this to be attributable just to (midocean) turbulence. In this period he seems to be struggling more that I would expect of a fully fit and current-on-type pilot; am I being unfair?

2. During this 35 second period I surmise that the PF's attention was focussed strongly or exclusively on his display re. roll - which was evidently working perfectly well - to the possible exclusion of a better scan.

The PNF starts very rightly to 'nag' towards the end of this period, and what happens afterwards seems to me uncannily like what instructors recognise as 'freeze' when a student is unintentionally overloaded. (My compliments to BEA for their very helpful combination of CVR and FDR events).

I am neither willing nor able to seek to apportion any blame - I have never flown a sidestick aircraft, nor indeed any without the 'luxury' of tactile feedback on the controls - can Airbus drivers please comment on the significance or otherwise of the early roll-axis traces?

CONF iture
7th Aug 2011, 22:49
Well who cares what I'm doing for a living.
As you demonstrate some difficulty to accept anyone to be critical on the Airbus sidestick philosophy, it is fair to ask if you have any practical experience, preferably in a multi crew operation ... You don't have to answer, of course, but it could help to put some weight behind you statements.

SIDE STICK INDICATION ON PFD IN FLIGHT :
Another gadget that would require direct visual attention.
Don't you think AF crew had already too many direct visual things to look at ?
Nothing like fully visible yokes, visible by all, and so, without direct visual attention.

But you don't have to trust me. Still, I'm talking by experience ... what about you ?

In fact, because nobody using those aircraft seems to be very concerned about such an "obvious" need or it would have been made possible from two decades.
You are misinformed.
See earlier reply (http://www.pprune.org/3193246-post35.html).





On the other hand, you just hate this brand, whatever their reasons being to do it like that. I can't remember a single feature you actually liked about an aircraft you are supposed to fly. On my side, I'd like to know why is your grief so deep? Personnal vendetta?
Is it supposed to be an argument ?
I'm sure you'd be better talk about the FDR data you like to claim as "NORMAL"

takata
7th Aug 2011, 22:54
Other than the test-flight at Toulouse, two Sri Lankan A330s were shot up at Colombo airport, a Malaysian A330 was written off by a chemical spill, and the loss of AF447 and Afriqiyah 771 makes six.
Right and thank you.
Hence, as the original poster was talking about "air transport safety related to type", and not about insurances fees, it looks to me that war actions are irrelevant (or any terrorism/criminal act), as well as cargo hazards on the ground/ maintenance issues or manufacturer test flight programs (same for the long list of supposed "major accident").

Hence, one won't refrain from increasing by 200% those (statistically) close to zero figures in order to scary as many people as possible.

The reality is that, hopefully, there was only two operational transport losses : AF447 and Afriqiyah 771, none of which, so far, revealed a potential tendency of the type to fall from the sky per dozens in the close future, while it did not also during the last 20 years.

Regardless of the number of representative hull losses (which could be much worse for the 320/330) {vs 777} the reality is that its B = 0 and A = to many.
More than zero is always too many.
Concerning your proposal, why not adding all Airbus (A300 + 310 + 320 + 330 + 340 + 380) for comparing them vs. B777 exceptional service records inside the entire Boeing fleet?

I'm sure that your point will be even more telling about the danger of boarding such an Euromade flying garbage. Most of you guys, are sounding like your worst press makers each time an Airbus is lost; whatever the reason, the question of the type "safety" will be raised first, even before a single fact would be established concerning the circumstances.

Today, I don't find this obvious behavior anymore chocking but quite succesful after reading occasionnally a couple of post from here. There is no more objectivity remaining concerning such matters and our lawyers are the only one to win, everytime, at this little game.

Nonetheless, I can also predict that Airbuses accident statistics will increase in the future, until we'll run out of gas, as their share of the skies is also increasing daily. Consequently, it's everyone interest - pilots, crews and passenger - to stick more to the facts rather than pre-digested opinions.

JJFFC
7th Aug 2011, 23:03
The chronology below clearly shows that the crash has nothing to do with the pitots tubes, nor the stall warning, nor the sidestick : the LS and the Capt. were fully aware of the stall and of the solution to the stall. It is prooved by the fact that only 21s after the pilot in the RS took control of the plane, the pilot in the LS was urging him to go down and was asking for the Captain because of the RS attitude.

Untill the end, the LS and the captain tell the RS to go down and keep the wing horizontal.

But the RS' brain was unable to do it, even when he said that he will obey and go down !

In fact, the chronology shows a real fight between two pilots, the "devil" in the right seat (RS) and the "good" in the leftseat.(LS)

The crash occurs because the LS could never took the priority over the RS. When he did, either the RS re taked immediatily the control either there were dual inputs !

Had the RS or the Captain a solution to stop the RS for giving inputs ?

It seems that a "knock down" would have been the right solution.

But, how can the designer or the AF management predict in which seat is the good or the bad ?

IMO, there is NO solution to the case in a commercial plane if a pilot don't obey to the Captain.

Even in an Army, a martial Court is necessary to decide this kind of debate.

And NOBODY can predict if the Capt or the copilot is the devil.

I really think this crash has nothing to do with A vs B or AF vs any other flagship.

____________________________________________________________ ___

In the following:
· LS using the Captain sideslick: left seat is PNF except if he is mentioned as PF
· RS using the copilot sideslick: right seat is the PF except if he is mentioned as NF
2 h 10 min 06 The flight control law changes from normal to alternate. RS : “I have the controls”
2 h 10 min 25: Wing anti-ice
2 h 10 min 26: The FD 1 and 2 become available again (HDG and V/S modes).
2 h 10 min 27 to 2 h 10 min 31 : LS “Watch your speed Watch your speed” RS “Okay, okay okay I’m going back down” LS “Stabilise” RS “Yeah Go back down”
[Only 21 s after RS took the control, the LS understood that the RS is not flying properly BUT has to wait for the Capt.]
2 h 10 min 49: LS “(…) where is he er?”
2 h 10 min 51: SV : “Stall, stall” + cricket continuously
2 h 11: LS “Above all try to touch the lateral controls as little as possible eh”
2 h 11 min 06 : LS : “(…) is he coming or not?”
2 h 11 min 32 (…) I don’t have control of the airplane any more now I don’t have control of the airplane at all
2 h 11 min 38 : LS “Controls to the left”
[ 1 mn and 32s after RS took control, LS takes control, BUT only for 2 s because the RS re takes control without announcement : a huge fault !]
2 h 11 min 40 : RS takes over the controls. The RS sidestick is positioned:- left in stop position - nose-up to two thirds of the stop position.
2 h 11 min 43: Capt “Er what are you (doing)?” LS “What’s happening? I don’t know I don’t know what’s happening”
[ The RS has been flying like a fool for 1mn and 37s BUT the LS doesn’t dare to tell to the Capt. that the problem is actually the RS]
2 h 11 min 45 : End of “Stall, stall” warning + cricket
2 h 12 min 04 2 h 12 min 07 : The airbrakes are controlled and deployed.
2 h 12 min 07 : LS “No above all don’t extend (the) “
2 h 12 min 17: SV : “Priority right”
[ It looks like the RS and the LS were fighting for the control, unfortunately the RS took the priority]
2 h 12 min 19 : Capt “The wings to flat - horizon the standby - horizon -The horizon (second)”
2 h 12 min 27: LS “You’re climbing” SV : “Stall, stall”
2 h 12 min 30: RS “Am I going down now?” LS “Go down”
2 h 12 min 32 : Capt :”No you climb there”
2 h 12 min 33: I’m climbing okay so we’re going down
2 h 12 min 45 : RS “On alti what do we have?”- LS “What do you mean on altitude?” – RS “Yeah yeah yeah I’m going down, no?” – LS “You’re going down yes” Capt. “Hey you’re in … get the wings horizontal Get the wings horizontal”
2 h 12 min 59: Capt “The rudder bar”
At 2 h 13 min 23: SV : “Dual input”
[ From now, a series of dual input shows that the fight between the two PF is going on until the end with the Capt. Giving (good) advices]
2 h 13 min 25: RS : “What is… how come we’re continuing to go right down now?”
2 h 13 min 38: Capt : “Careful with the rudder bar there”
2 h 13 min 41 : SV : “Dual input”
2 h 13 min 43 : SV : “Dual input”
2 h 13 min 45 : SV : “Dual input”
2 h 13 min 47 : SV : “Dual input”
2 h 13 min 40 RS: “But I’ve been at maxi nose-up for a while” – Capt “No no no don’t climb” – LS “So go down”
2 h 13 min 45 LS : “So give me the controls the controls to me” RS : “Go ahead you have the controls we are still in TOGA eh”
2 h 14 min 05 Capt “Watch out you’re pitching up there” LS “I’m pitching up?” RS “Well we need to we are at four thousand feet”
2 h 14 min 21: The RS seat takes over the controls.
2 h 14 min 26 : The LS sidestick is positioned nose-down and right. The RS sidestick is in stop position nose-up and around neutral in lateral.
2 h 14 min 28,4: End of recordings

Mimpe
7th Aug 2011, 23:19
Hi Karsten

my point is that egalitarian CRM proceedures miss the glaring fact that in an incipient major aircraft upset, your most experienced pilot will, on average, give your aircraft berween 25 - and 225 percent increased risk of survival.This is a resource not used by the crew . In this accident the least experienced pilot retained (ineffective)control of the aircraft from autopilot failure zoom climbing to 38000 ft , stalling, then down to 4000 ft .

The Aircraft was hand flown from a stable configuration into a stall situation, albeit unwittingly complicated by the autotrim..... leaving the best aviation experience/resource in the non control role , or absent from the cockpit and not decisively involved throughout.

The problem was being in a thunderstorm at is worst locus of intensity and widest diameter, thence a skill, perceptual (including spatial disorientation) and CRM one on the pilot/company side, worsened by design faults with the aircraft ( pitots, autotrim, stall warning parameters useless in a mjaor attitude upset, no A of A display, digital readouts vs analogue readouts worsening performance in emergency environment, unobserved sidestick)

SLFinAZ
7th Aug 2011, 23:24
takata,

I simply viewed this from the perspective of equivalent models. My perception is driven by my belief that modern airline design is systematically driving the aviator from aviation. I'm sure others will disagree but overall I feel that the overall quality of professional pilots is in serious decline.

I recognize that profound differences exist between the private (student, sport, recreation, PPL) and professional ratings (commercial up). However the world can be easily divided into two categories...those who have soloed and those who haven't. Overall safety specific to this are constant. There are very few accidents specific to student pilots....in fact I believe we have more accidents involving low time PPL holders who prematurely graduate to complex singles or fly in conditions for which they are not fully qualified (or both).

The harsh reality at the commercial level is that the continuing development of automated systems is financially driven. When you contemplate that the average pilot now spends more then 85% (closer to 95% in many cases) observing and often has only 300 hrs of total time prior to type rating on a commercial airliner a pilot with 3,000 total hours may have less then 200 hours of actual lifetime flying experience when you factor on the amount of automated flying involved in the initial 300 hours. The PF had roughly 2,900 hours total and much less in an A330. I bet he had less then 10 hours of actual hand flying experience in the A330 in the year prior to the accident.

jcjeant
7th Aug 2011, 23:49
Hi,

JJFCC
It is not A vs B but PF vs PNFThank you :ok:
You nail it very well (incompetency)
Some may ask how this pilot (PF) obtained his license and if any test flights (and in what conditions) has been performed for verify if he was able to replace and take duties of a captain ...
That's all for the human side
Now we can concentrate on other matters .. if any :8

bubbers44
8th Aug 2011, 01:33
It is not A vs B but PF vs PNF

Thank you
You nail it very well (incompetency)
Some may ask how this pilot (PF) obtained his license and if any test flights (and in what conditions) has been performed for verify if he was able to replace and take duties of a captain ...
That's all for the human side
Now we can concentrate on other matters .. if any

I think the captain could have flown out of this situation with attitude and cruise power for their weight and altitude. 2 degrees nose up and about 80% N1 would be a starting point. Leaving the 2900 hr pilot in charge was probably their procedure even though the Left seat guy had a lot more experience.

The PNF should have taken over when the RS pilot panicked and pulled up but didn't. When I was flying 8 years ago this would have never happened. We could all hand fly at any altitude it didn't matter if the FO or Captain flew.

Now we train systems managers to fly a computer so things are a lot different. I loved the way it was when pilots could physically fly the airplane. My airline still has only old school capable pilots not needing a keyboard to fly. 90% of my flying is with a competent crew with us.

bubbers44
8th Aug 2011, 01:40
It is not A vs B but PF vs PNF

Thank you
You nail it very well (incompetency)
Some may ask how this pilot (PF) obtained his license and if any test flights (and in what conditions) has been performed for verify if he was able to replace and take duties of a captain ...
That's all for the human side
Now we can concentrate on other matters .. if any

Sorry, I don't know how to do quotes yet, attach this to the post prior. Thanks.

MountainBear
8th Aug 2011, 03:30
The chronology below clearly shows that the crash has nothing to do with the pitots tubes, nor the stall warning, nor the sidestick

What rubbish. If the technology can't correct for pilot error then it's rubbish technology. That's what FBW is all about. What part of the word "protection" in "flight envelope protections" doesn't you understand. The software is to protect the pilot from screwing up. It didn't. It failed.

People keep talking about pilot error as if that's the conclusion of the matter. Pilot error is just the beginning. Every single major advance in flight safety over the last hundred years has happened because "pilot error" was not an acceptable answer. The fact that the pilots in AF447 screwed up is as obvious as it is irrelevant. The pilot is just one cog in the system. If the system cannot compensate for errors in the system then it isn't a robust system.

jcjeant
8th Aug 2011, 04:28
If the system cannot compensate for errors in the system then it isn't a robust system.

A common mistake that people make when trying to make something completely foolproof is to underestimate the ingenuity of complete fools...

Zorin_75
8th Aug 2011, 07:39
If the technology can't correct for pilot error then it's rubbish technology.
It's a little hard to keep up, did I miss the memo that we're bashing Airbus for providing not enough automation now?

BOAC
8th Aug 2011, 07:51
Zorin - I think the general drift is that when you sell a package that supposedly protects those silly humans from themselves, it should.