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AF447 final crew conversation - Thread No. 1

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AF447 final crew conversation - Thread No. 1

Old 16th Oct 2011, 21:02
  #121 (permalink)  
 
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Lyman . . .

I think most pilots understand what was happening here, and only in hindsight, of course. .
Huh...?
Voice generated stall warning, "STALL, STALL, STALL..." intermittent up to 53 seconds.
My ears are not pots to piss in. I WOULD hear that, and I WOULD respect a stall warning, and I WOULD respond to it! To be sure, I WOULDN'T be pulling back on the stick and climbing 3000 feet, no matter what the Indicated Air Speed says. ...But maybe that's because I'm a captain with 20,000 hours.

They didn't get STALL data such that they followed it in, and not knowing they were STALLED, they did not think to control out of it.
Huh...? They didn't hear the stall warning? Didn't know that it MEANS stall?

From 2 h 10 min 05, the autopilot then auto-thrust disengaged and the PF said "I have the controls". The airplane began to roll to the right and the PF made a left nose-up input. The stall warning sounded twice in a row. The recorded parameters show a sharp fall from about 275 kt to 60 kt in the speed displayed on the left primary flight display (PFD), then a few moments later in the speed displayed on the integrated standby instrument system (ISIS).
At 2 h 10 min 51, the stall warning was triggered again
After the autopilot disengagement: The airplane climbed to 38,000 ft,
the stall warning was triggered and the airplane stalled, the inputs made by the PF were mainly nose-up, the descent lasted 3 min 30, during which the airplane remained stalled. The angle of attack increased and remained above 35 degrees, the engines were operating and always responded to crew commands. The last recorded values were a pitch attitude of 16.2 degrees nose-up, a roll angle of 5.3 degrees left and a vertical speed of -10,912 ft/min.
These were 2 copilots who couldn't fly manual in IMC.
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Old 16th Oct 2011, 22:10
  #122 (permalink)  
 
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Originally Posted by Lyman View Post
He held back stick...... What could go wrong, he flies an Airbus?
Why ? Why did he climb ? His first action should be level off. PNF doesn't know either - his comments seem to imply PF is not aware he is climbing.

And what could go wrong if you climb inexorably - Airbus is the first a/c without a service ceiling ?

He's in ALTERNATE LAW, what could go wrong, he is Alpha protected?
He doesn't know his a/c flight modes / laws then.

Wicked speed, insane descent, He'll wait for the a/c to "raise" the nose.
Nose is already up - so you suggest he isn't looking at pitch either ?

What else could be wrong, it can't be STALLED.
Yep, because otherwise we'd have had a stall warning... oh, we did, for 50odd secs, but that's ok that's gone now because we've recovered from that stall, without ever putting the nose down...

He had it figured, wrong, but figured. His idea of recovery was to allow the a/c to recover, as it always does.
But it doesn't - or at least not as I understand it - in particular if you get into alpha-prot mode, you have to act to get out of it. Leave it there and I think you'll end up in a phugoid around your max alt.

Ultimately, all three figured to PULL was the call. ALL THREE.

It happened another way? Funny thing, Airbus pilots aren't quite as harsh on these three, wonder why? They know something we don't?
Maybe they also had no training (at all says the report), and no practice, in hand-flying at altitude. Maybe they have since had 447 scenario thrown at them in sim, before such training, and it didn't go so well... (or they have had the training and then the excercise and are thinking how they might have done untrained).
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Old 16th Oct 2011, 22:11
  #123 (permalink)  
 
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If every pilot had to be trained for every possible situation he could get into to be a qualified pilot he would be in his 40's to get his first job on his own. Pilots are usually people that learn the basics and understand the results of altitude, type of airplane and how thousands of situations can confront you.

A qualified pilot knows how to deal with never before encountered problems. We all did but some people here believe these FO's were not at fault because they were not taught high altitude full stalls in an airplane advertised as stall proof. Well they got into alternate law and couldn't deal with it because it did stall and they didn't know how to recover. Who is at fault for that? I don't blame AF or AB, I blame the pilots. If AF hired them knowing they were not able to handle a stall at all altitudes then maybe they get some blame too.

If these two were allowed to fly by themselves without the captain in the cockpit they should have been more qualified in my opinion.
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Old 16th Oct 2011, 22:19
  #124 (permalink)  
 
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Originally Posted by Machinbird View Post
Dozy, it isn't exactly a democracy in the cockpit. It is more of a meritocracy. You warn the other person that they are f'ing up if time permits and then act if you hope to be bouncing your grandkids on your knee.

Problem is that PNF did not act, he punted the problem to the Captain. That is as much of a problem as is PF's handling of the aircraft.

The reasons the PNF did not act need to be understood and corrected.
I think (hope) there will be signficant work on that in the HF report. BEA has already expressed opinion and recommendation (see 4.1 of latest interim report)
an absence of training and practice for a crew consisting of
two copilots does not guarantee a level of performance equivalent to a crew consisting of a Captain and a copilot when faced with a degraded situation.
[recommendation] define additional criteria for access to the role of relief Captain so as to ensure better task-sharing in case of relief crews.
AF have already made some changes - 5.1.2 in the report refers.
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Old 16th Oct 2011, 22:33
  #125 (permalink)  
 
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GlueBall. Not like you to be coy. He had a STALL WARN at the drop, and the STALL WARN with STALL was concurrent with NO CUES. He'd been briefed STALL could be bogus with UAS, so let's dismount the high horse?

Immediately with the elevated noise in the cockpit, and what do YOU do?

You and others keep repeating data that is not untrue, but needs to be considered with other data. And you do it to frame the Pilots as stupid, newby, ne'er do wells. ENOUGH.

His screen was not recorded, remember? What did he see? What do you think he saw sufficient to condemn him? Was there no data to be recorded? OR was there data that was corrupted, and after boluxing up the deal, did not make it to the DFDR?

You are stuck on "54 SECONDS OF STALL WARN...bla..bla..bla.." Without completeing the picture with what I just posted.

UAS when this deal happened was a crapshoot. 31 crews landed safely, this one went in the drink.

31:1. You like those odds? I cannot believe an underwriter would indemnify anyone with the state of UAS and the sloppy workarounds given the crews forced to fly with it.

After 447, the AF pilots went on strike to cause the Line to get serious about r/r Pitots. Airbus was later forced to issue bulletins, one of which said: DO NOI RESELECT AutoPILOT, the a/c may climb without command.

Come to think of it, 447 did just that.

This: Your A/P disconnects. What do you do? the a/c is trending down, and rolling right. You don't know UAS is what caused the loss, it may be MET. You do nothing? Or do you risk losing something against which to frame PITCH and POWER, NOT KNOWING that is indicated?

ENOUGH.

Infrequent flyer, I've posted this too many times, you know what I think,. and rehashing it solves nothing.

I believe, Heartr and Soul, that taken with some objectivity, there is reasonable explanation for the mistakes that were made.

Except: With UAS, you get AL2. ROLL is direct, PITCH is not, it is commanded through a filter, and Elevators are subject to AUTOTRIM.

To me, what's left of NORMAL LAW amounts to a half assed autopilot, not FBW, so why would you want partial autopilot sharing command of your controls?

seriously
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Old 16th Oct 2011, 22:51
  #126 (permalink)  
 
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I am not a pilot but I have read this whole thread and would like to get this clarified. The captain was saying 'No, no, no, don't climb'. Doesn't that indicate that he is aware of the stall? And after the computer voice is saying 'pull up, pull up', the captain replies 'Go on: pull'. Is he saying that because he realizes that it is impossible to recover from a stall at below 4000 ft?

Also, why doesn't the captain resume control? Is he just standing there the whole 3.5 minutes?
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Old 17th Oct 2011, 00:19
  #127 (permalink)  
 
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No, he got there in the last minute and couldn't figure out what they had done. He needed to be there in the beginning to know what was happening.
He is the only one I feel had nothing to do with the crash. He was taking his required rest. The two FO's got it into the stall situation it was in. It was too late for him to fix it.
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Old 17th Oct 2011, 00:23
  #128 (permalink)  
 
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No, he got there in the last minute and couldn't figure out what they had done. He needed to be there in the beginning to know what was happening.
He is the only one I feel had nothing to do with the crash. He was taking his required rest. The two FO's got it into the stall situation it was in. It was too late for him to fix it.
Maybe I wasn't clear enough; because that doesn't answer my question: Doesn't the fact that he told the pilot not to climb, point to that he was aware of them being in a stall?

Also the claim you make that he had to be there to know what was happening doesn't really jive what I have read in this thread. Shouldn't he have been able to tell they were in a stall judging from the loss of altitude? And why didn't he resume the control of the airplane? Why did he just stand there?
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Old 17th Oct 2011, 00:37
  #129 (permalink)  
 
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Originally Posted by kweken
And why didn't he resume the control of the airplane? Why did he just stand there?
Correct, it is surprising he did not push to get back on his seat and have control on the sidestick.
Actually he came back 2 min 40 sec before the end.

AP remained disengaged, but could we know if they tried to re-engage one ?
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Old 17th Oct 2011, 00:40
  #130 (permalink)  
 
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What do you mean by "but could we know if they tried to re-engage one"?
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Old 17th Oct 2011, 00:54
  #131 (permalink)  
 
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I don't think any captain with less than one minute of observing what is happening out of sleep could figure out why they are descending 10,000 fpm with the nose up. We normally have competent copilots so don't think this can happen. I always trusted mine. Mine had lots of experience too. These two didn't. We didn't hire people with under 5,000 hrs. It makes a big difference when you hire unqualified people.
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Old 17th Oct 2011, 00:54
  #132 (permalink)  
 
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As the crossbars were visible by intermitence, maybe the crew may have been tempted to re-engage one AP. Would the FDR register an action on either AP pushbutton ?
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Old 17th Oct 2011, 00:55
  #133 (permalink)  
 
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Originally Posted by bubbers44 View Post
... in an airplane advertised as stall proof.
That's a misconception. The protections were "advertised" as being able to prevent stall, this is true - but the "FBW Airbus can't stall" myth came out of press misunderstandings and public misinterpretations. Other modern myths include things like "Apple computers don't crash and can't get viruses" and "ABS in modern cars means braking distances are shorter".

The common thread running through all these myths is that they contain a grain of truth, but have been transmogrified through retelling until they actually become untrue in themselves. Apple computers do crash (and how - believe me!), and in some situations ABS can extend overall stopping distance. People who work with these machines are supposed to know this, but they can't stop the myths from gaining traction.

In the case of the Airbus myth, it is the Normal Law protections that make it almost impossible to stall the thing as long as all systems are functional, but with the failure or disengagement of systems that those protections rely on the aircraft becomes no more difficult to stall than any other airliner in the sky. If the PF was not trained to know that, then it is a massive dereliction of duty on the part of those who trained him. If the PF was trained to know that and in a moment of panic - or under pressure - forgot, then it was a tragic mistake - and one that many more experienced pilots, including senior and decorated Captains, have also made in the past.
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Old 17th Oct 2011, 01:18
  #134 (permalink)  
 
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I don't think any captain with less than one minute of observing what is happening out of sleep could figure out why they are descending 10,000 fpm with the nose up.
He left the cockpit 9 minutes earlier (if I recall correctly). Do you think he had fallen asleep by then?

And what other cause can there be descending 10,000 fpm with the nose up other than a stall?
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Old 17th Oct 2011, 01:23
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My neighbor flies All Airbuses and claims alpha protection would make the Hudson River Sully landing easy. Now you are saying that is not true????
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Old 17th Oct 2011, 01:38
  #136 (permalink)  
 
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The Hudson landing was accomplished with Normal Law active due to the decisive action of the crew in getting the APU going. Had they not done so and relied instead on the RAT, then the ditching would have been in Direct Law, the protections would not have been active, and it would likely have eroded the safety margin somewhat.

That said, I'd take issue with use of the term "easy" regardless of the context - no water ditching could be considered that based on the things I've read and learned over the years.
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Old 17th Oct 2011, 01:51
  #137 (permalink)  
 
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Indeed, what do we know of PF's screens? If a/p was tried, (it had been tried, with uncommanded climb as a result before), and he was confused by his FD, well, who knows? For many reasons, including comment on the second STALL ("pas valide?"), no conclusions re: the right side actions are legit, at this point.
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Old 17th Oct 2011, 02:16
  #138 (permalink)  
 
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Cool

Hi,

Lyman
His screen was not recorded, remember? What did he see? What do you think he saw sufficient to condemn him? Was there no data to be recorded? OR was there data that was corrupted, and after boluxing up the deal, did not make it to the DFDR?
Indeed, what do we know of PF's screens?
May I ask .. what do we know of the NPF screens ?
Recorded ,remember ?
What did he see ? what do you think he saw was sufficient for not bother to take the command of the plane .. and let the PF to condemn him and al ?

bubbers44
than one minute of observing what is happening out of sleep
The captain was not out of sleep .. this is a urban legend
Please check the time chronology .. BEA report N3 and make some maths to know time gap of captain leave flight deck and captain enter again flight deck
How he can be already sleeping in this amount of time ?
I know that during the two last WW there was soldiers who marched asleep and falling on the ground like a ripe apple ..
If the captain was so tired .. I ask questions about his day of rest at Rio

Last edited by jcjeant; 17th Oct 2011 at 02:37.
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Old 17th Oct 2011, 06:36
  #139 (permalink)  
 
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Ok, even though my neighbor gave the Hudson river ditching credit to the autopilot I didn't agree with him because Sully had to manage his speed to stop his descent rate prior to contact with the water. Landing wings level is quite easy so I give all the credit to Sully for making the best out of a bad situation. I always flew Boeing aircraft by choice so know very little about what it is like to fly the AB. I retired before I had to be concerned with it.
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Old 17th Oct 2011, 06:51
  #140 (permalink)  
 
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That's a shame bubba, to have finished your career without experiencing the beauty of flying a FBW Airbus. A truly remarkable airplane.
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