AF447 wreckage found

[JJFFC]

@ JcJeant

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

(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]

@DozyWannebe

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]

Originally Posted by DozyWannabe

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]

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]

@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...

Originally Posted by CONF iture

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]

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]

DW

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?

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]

Originally Posted by DozyWannabe

...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.

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]

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]

Microphone strikes wall

Originally Posted by BEA #3, Page 43

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]

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]

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]

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]

Originally Posted by Fox3WheresMyBanana

OK, after reading the English version

Originally Posted by Fox3WheresMyBanana

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, and

Ok.

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]

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]

stall, or high speed stall?

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...eed-stall.html

[alainthailande]

Pilots pulling out of the BEA workgroup on AF447

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]

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]

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

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]

Originally Posted by DozyWannabe

@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.