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AF 447 Thread No. 5

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AF 447 Thread No. 5

Old 4th Aug 2011, 18:01
  #1541 (permalink)  
 
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PJ2

Well said. Much food for thought - enough to write a book, rather than a post, on current automation, the human/machine interface and line pilot airmanship standards/training. As you say re: FCOM......

Not the time/place for F/Os 32 & 37 to suddenly do their FLT350 hand flying training, under AB alternate law in UAS conditions in that part of the circadian rhythm over the ITCZ, but the CRM shortcomings now disclosed really didn't help matters. The PF tossed his coin, called heads (overspeed) rather than tails (stall), the PNF missed his opportunity early on to reach the right conclusion (I don't like the entire SS concept, but that's my prejudices and I won't impose them upon others) and the CPT never appeared to remotely catch-up with his plane in the apparent absence of any meaningful coherent reporting from his co-pilots as to what had already transpired.

All very sad, over in minutes, but a very long time being made by the industry......

Last edited by Welsh Wingman; 4th Aug 2011 at 23:04.
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Old 4th Aug 2011, 18:13
  #1542 (permalink)  
 
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Air France has formally submitted concerns over the stall warning system in the ill-fated Airbus A330-200 lost over the South Atlantic, after further clarity over the crash of flight AF447 prompted fierce defence of the aircraft's pilots.................Air France said: "At this stage there is no reason to question the crew's technical skills."
Stall warning controversy haunts AF447 inquiry
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Old 4th Aug 2011, 18:43
  #1543 (permalink)  
 
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Third time, first timer,


It was already said by the BEA, there was nothing wrong with the plane and IMHO the same can't be said about the PF. I was under the impression (and for more than two years) until reading the third interim report by the BEA in English, that the younger co-pilot (relief pilot) was the PF. But it never added up completely because, why experience didn't prevail? It did. Also, I couldn't understand why the most experienced co-pilot was screaming for the Captain to return? He didn't, it was the younger one and PNF. It is funny (Life likes that) that the Captain asked if the co-pilot (First Officer) had a pilot license online. This was omitted in the Interim Report #3 for some reason, I think, I can't find it.


FO: But I’ve been at maxi
nose-up for a while = He has been wrong far too long.
Cap: No no no don’t climb = Right but too late. Around under 4000 ft to impact too late.

Relief Pilot: So go down = Yes, but too late and not for long.

I got the complete picture now. I do not see how can we find the mark of a pilot before he/she goes under a real fire event. All the bells, whistles and gadgets won't work if no one pays attention to them or worst yet, decides to disregard them.
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Old 4th Aug 2011, 18:57
  #1544 (permalink)  
 
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VGCM66

You were correct first time. F/O 32 was PF in the RHS throughout. F/O 37 replaced the CPT in the LHS. F/O 37 had been resting (dozing) until not that long before the incident, which may partly explain his initial failure to get on top of the matter (UAS SOPs etc). Back to PJ2 - sitting for hours monitoring systems and then the speed of this emergency requiring instant quality hand flying airmanship skills (why the particular pitot tube model problem should have demanded a more urgent response, given the modern "hand flying" training and operating environment, given the history from Stony Point via Birgenair and Aeroperu)....

Last edited by Welsh Wingman; 4th Aug 2011 at 23:03.
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Old 4th Aug 2011, 19:56
  #1545 (permalink)  
 
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You were correct first time. Bonin was PF in the RHS throughout. Robert replaced Dubois in the LHS. Robert had been resting (dozing) until not that long before the incident, which may partly explain his initial failure to get on top of the matter (UAS SOPs etc).
So the youngster got a hold of the SS and from then on the FO was reluctant to take it back away from him until the very end? In both scenarios it seems that the FO dropped the ball (no assertion). It doesn't make sense from his shoes. So, he was the one screaming for the Captain to return? And the Captain before leaving said at one point: He (FO) will take my place? If so, that kind of place him in charge, doesn't it?

What an innocent mess?
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Old 4th Aug 2011, 19:56
  #1546 (permalink)  
 
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Basic flight instruction and training

I know this is simplistic, but I'm not sure many here are aware of some of these fundamentals.
Knowing what to do and demonstrating that you can do it are two different things.
BASIC FLIGHT INSTRUCTION AND TRAINING
SIMULATOR AND FLIGHT TRAINING
I think there is a basic mis-understanding of what flight training is all about.
Following a pilot's initial training in any aircraft, in upgrading to a commercial airplane there is a series of stages. From basic flight to specific maneuvers visually and under instruments.
Assume the basics are known and understood. Push forward go down, pull back go up etc.
Whenever a training/simulator session is set up, the rules are understood. Altitude: 100 feet plus or minus. Heading: plus or minus 10 degree. Airspeed: plus or minus 10 kts.
Whatever procedure is being attempted, these criteria must be adhered to. It requires extreme focus, and development of feel and touch.
In dealing with an emergency, whether a fire, loss of engine or anything less, it then requires coordination to handle each one. If the pilot flying tries to deal with the procedure, it is not possible to read and follow the checklist at the same time.
The proper protocol is to hand off the flying to the other pilot who is them responsible for keeping the plane under the foregoing limits, while the pilot reading the checklists assures that each component complies.
But well before this, while knowing what these limit critieria are, a pilot must be able to demonstrate a capability of doing so.
Knowing what the plane can/should do is different than doing it and demonstrating it.
Without ever handling a plane/simulator it is not possible to accomplish any of this the first time out. Let alone in a real life situation, with turbulence and stress.
Here, with many different laws and conditions without hands on training in each phase, successful flight is literally impossible, as we are seeing in this last 4 minutes.
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Old 4th Aug 2011, 20:18
  #1547 (permalink)  
 
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VGCM66

CDB even had to check, when he switched with the dozing F/O 37, that F/O 32 was qualified to implicitly take command as the PF (and had been the PF from GIG). Given my vintage, don't even get me started on reinforced crews issues (2 CDBs and 1 F/O, not vice versa!). But save only for the ITCZ (and the CMB that triggered the disaster through the pitot tube failure), it should have been an uneventful systems monitoring leg of the oceanic transit. F/O 37 had not been placed in command as the more "senior" of the two F/Os, and the BEA are criticial of the lack of designated roles for F/O 32 & F/O 37 before CDB departed for his rest break, and note F/O 37's concern at the delays in CDB returning to the cockpit (F/O 37's actions, or lack thereof, are likely to feature further in the final report - psychologists/behaviourists etc).....

Last edited by Welsh Wingman; 4th Aug 2011 at 22:59.
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Old 4th Aug 2011, 20:43
  #1548 (permalink)  
 
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3holelover:
Forgive my ignorance of French please, but is there different language used in French for "Pitching" up/down vs "climbing/descending"? The use of phrases such as "you're going up" and "you're going down", sounds (in the transcript) to me to have added to confusion.
Pitching up is "cabrer".

The PF uses this, at one point:
2 h 13 min 40
PF: Mais je suis à fond à cabrer depuis tout à l’heure
But I'm nose up to the limit since earlier

And then again 2:14:05.

Pitching nose down would be "piquer"

It also struck me how (with the few exceptions just noted), neither PF nor PNF, nor the CDB once he returns, ever speaks of pitching up or pitching down. They constantly speak of going up and going down.
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Old 4th Aug 2011, 21:01
  #1549 (permalink)  
 
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A33Zab-- Selected vertical speed? (Post #1497)

I've deleted this post as I misinterpreted the selected vertical speed (green line) to be intermittant commands in the A/C computer, whereas they are intermittent sampling of commands having continuous effect (as I interpret takata's comments below). I'm leaving this line so as to not change all the following post numbers. --OE

Last edited by Old Engineer; 4th Aug 2011 at 23:14. Reason: Wrong interpretation of chart = no value to discussion
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Old 4th Aug 2011, 21:08
  #1550 (permalink)  
 
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Originally Posted by PJ2
Also, the Airbus side stick does have artificial feel just like a control column/wheel and it works very well.
I thought the Airbus side stick was simply spring-loaded to neutral. I would not call that an artificial feel.

An a/c with mechanical controls sends back two qualitative messages to its pilot as regards the pitch axis.
1/ speed: whether you are fast or slow, the stick is stiff or limp.
2/ trim: the residual force on stick required to maintain an attitude tells you where you are relative to you trim speed
I believe an Airbus side stick conveys neither speed (C* law) nor trim (autotrim). Or did I missed something ?
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Old 4th Aug 2011, 21:13
  #1551 (permalink)  
 
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Hi VGCM66,
Originally Posted by VGCM66
It was already said by the BEA, there was nothing wrong with the plane and IMHO the same can't be said about the PF. I was under the impression (and for more than two years) until reading the third interim report by the BEA in English, that the younger co-pilot (relief pilot) was the PF.
One day, considering that final BEA report will not be published before next year (1st semester 2012), we'll have to make a FAQ about this thread for "First Timers" who seems to be lost in BEA reports translation... but, believe me, I understand perfectly the issue.

So, lets go for one more explanation:

1. "Relief" pilot, in Air France terminology, means "co-pilot (F/O) acting as Captain"; hence, he is the pilot in charge (PIC) when the captain is resting. It is not the same meaning than "limited duty officer", for "relief" at cruise, like many other companies are calling it.

2. Air France longhaul crews are composed of the "commandant de bord" (captain) and two fully qualified co-pilots (F/Os) having the exact same rank (whatever their age).

3. When captain is leaving the deck, he should decide whilch one of his two F/Os will be the pilot in charge (PIC) during his rest.

4. The officer designated as PIC must be the pilot flying (PF) during his rest. (this part was changed after AF447)

Consequently:
AF447 used this system and when Captain (no name please) took his rest:
- Pilot Flying (PF), being the pilot in charge (PIC), was the 32 years old F/O and was seated in RHS (Co-pilot seat in CVR/DFDR table).
- Pilot Non Flying (PNF) was the 37 years old F/O and was seated in LHS (Captain seat in CVR/DFDR table)

Quite disturbing, isn't it?

All along this thread, we are refering to the, Captain, PF (RHS) and PNF (LHS) as at 02:10UTC. But at some point, PNF could be the one flying the aircraft !
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Old 4th Aug 2011, 21:31
  #1552 (permalink)  
 
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takata

Your post should be mandatory for all new joiners to the thread.

As regards your question, you may imply that but I could not possibly comment......
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Old 4th Aug 2011, 21:36
  #1553 (permalink)  
 
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Old Engineer . . .

I don't think we can deduce much from the given fractional positions of the stick. It could just as well have been given as a percentage or in another base. The stick position will have been converted to a voltage, and the voltage then digitized, for input into the computer, perhaps with some cleanup along the way, before being recorded on the FDR. The fractional notation is for ease of digestion by the reader.

Sampling rates are another issue. Could be anything, from the rate you suggest to some artifact of processing the data. The sampling rate, recorded stick position, and other recorded data are chosen for logical reasons, and would not be limited by the speed of the computer.

Perhaps SensorVal or others would care to elaborate.
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Old 4th Aug 2011, 21:42
  #1554 (permalink)  
 
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Bear:
... why would the crew speak twice of Altitude, than finally, "hoping a Pull Up, we are at 4000".
What matters is what they think of what THEY spoke!
"@[email protected]" one second after the other.
I've called out altitudes in a descent as an alert to a PF more than once. Tone of voice will vary with situation.
Does one of them not 'get' the VSI, and someone is trying to REMIND? At 8000, than 4000 feet? To me, and it is a GUESS, it means they are worried about Overspeed, ... why, In my opinion, they were not speaking STALL!

As in: Captain : "N'est-ce pas possible!!" "****in A, we're STALLED"
Indeed, he may have been thinking that, but as I noted above, had to deal with the denial phase of a pear-shaped situation. He went about other tasks, as there were plenty to choose from, or so it may have appeared to him.
Three qualified Pilots ignore STALL WARNINGS and input near constant NOSE UP.
The fellow in the RHS seems to have done most of that, even with Monsieur Robert nagging him about his nose attitude. Somewhere in this discussion, I see some ideas that even after the control change, you had two people trying to move the control stick. That isn't good.
You are not mistaken at all. PF disabled PNF stick, using priority, during the last 10 seconds or so. Note that the last imputs from the PNF reverted also to nose down. The vast majority of his few imputs were ND anyway.
(This is Not Colgan for silly sakes)
I mentioned that to Dozy when he first brought it up. I agree with you on that.
"I think we have crazy speed!"
Is he saying "Way Fast" with no airspeed indication? Disorientation, evidence of.
Originally Posted by [B
HN[/B]] Correct, but don't forget that static pressures are affected also, reading high. Pitot minus static can become negative in extreme cases, as mentioned in one of the BEA reports.
Why is static reading high? Ice, or something else?

Smilin' Ed: OK, I see where you are coming from.

Machinbird:
The computers/ADRs, it appears, cannot be trusted with the data in extreme conditions.
That may be true, but I don't think A330 was designed with "extreme flying" in mind.
Essentially airspeed has been given authority to outvote AOA (which we already knew from the stall warning fiasco) but this is not a good situation for present and future AOA installations in Airbus aircraft. This I consider to be a fundamental engineering error, but one that can fixed, probably by better software.
I use the word error, because AOA and airspeed are both fundamental aircraft performance data, but independent of each other and derived independently. To then mix them together and prioritize them is simply bad logic.
Food for thought.

BOAC
To anyone puzzled by the nose-up 'pull' at 4000', I ask what exactly would you suggest they did instead at 4000' with around 10,000 fpm down? I think we are down to pretty basic human instinct here.
If nothing else was working, revert to basics. I might have done the same, if I didn't realize I was stalled. Try something, anything.
".the copilots had not received any training, at high altitude, in the “Unreliable IAS” procedure and manual aircraft handling."
Is this perfectly normal and would this apply to other airlines as well?
One hopes not.
... I keep wondering about the FD's. As you said, when reengaging, they take the altitude of the time as their new reference, and the horizontal bar will (with the plane diving down ) give an UP order to the pilot, who is trained to follow it.
They(the FDs) should have been switched off on both sides from the very moment when the loss of valid airspeed indications became clear to the pilots : emergency procedure on page 81

In fact they (the Fds) were not cut off, so the bars on the displays kept coming on, then off, and one wonders if the horizontal bar, which one is trained to following, was not one of the reasons the flying pilot kept pulling upwards ?
Food for thought.
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Old 4th Aug 2011, 21:54
  #1555 (permalink)  
 
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Originally Posted by RatherBeFlying View Post
in an ideal piloting environment I could perhaps be persuaded.

But when humans are involved, errors will happen.

PNF may have clued in had he seen his ss sitting on the back stop.

My underlying concern is that when stuff goes wrong, good information is needed for the crew to put things right.

Among other factors, ss position and some red on the altitude/VSI display might have alerted PNF even though it seems he was too nice a guy.

PNF does not seem to have had any positive ideas about what needed to be done -- nor did CDB.
PNF seemed perfectly well "clued in" when it all started to go wrong - he knew PF was over controlling roll and chastised him for it, he knew PF was climbing when he shouldn't have been. In fact PF is the one who seemed unaware of what he was doing with his own SS.

None of them seem to have recognised stall, even when the warning was continuous, no recovery is ever discussed or actioned. With the possible exception of TOGA - not sure about that, I almost get the sense that PF is saying "can't be stalled, I'm in TOGA", but can't be sure (anyone else read it that way ?). In fact looks like PF thinks he's over speed if anything.

Captain I feel sorry for, he comes back in to stall warnings, AOA already so high that instrument data is going haywire left right and centre, no visual reference, and he has to work out what's happened without any info other than "we lost it". He has only 2 mins to diagnose stall and have the confidence to order 30deg or more nose down to attempt a recovery. I don't think hereally had a chance to save it from then.
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Old 4th Aug 2011, 21:58
  #1556 (permalink)  
 
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AF447 used this system and when Captain (no name please) took his rest:
- Pilot Flying (PF), being the pilot in charge (PIC), was the 32 years old F/O and was seated in RHS (Co-pilot seat in CVR/DFDR table).
- Pilot Non Flying (PNF) was the 37 years old F/O and was seated in LHS (Captain seat in CVR/DFDR table
I get more and more confused. Could we agree whether the following was true?

1. The officer who was resting prior to 2am was F/O 37.

2. The officer who 'wasn't sleepy' was F/O 32, who has also been PF from Rio.

3. The Captain woke F/O 37 and said (to F/O 32) that the older officer was to 'take my place'. By this he meant F/O 37 was to sit in the LHS, not to be PIC.

4. The Captain asked F/O 32 if he was certified, presumably to be PIC from the RHS. Presumably this question had not arisen on the outward leg.
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Old 4th Aug 2011, 22:04
  #1557 (permalink)  
 
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Originally Posted by airtren
I've asked the question myself, and have contemplated several speculative explanatory scenarios, due to the limited official information at the time. I've posted one of the scenarios a week, or two, before the BEA report was made available. The posted scenario was that at AP disconnect, the AP was in the process of responding to a drop in altutude, and roll due to heavier turbulence, which was interrupted by the AP disconnect. So the PF reaction was to continue the AP's action with NU, and roll.

The BEA Report made available recently brings more information.
The graphs at the end of the document seem to provide several concurring elements to support the scenario I've considered:

1. there is a slight altitude drop on the Altitude graph, right before the AP disconnect - see page 108 of the English version of the report. The drop is very small, and it's hard to tell how much it is - maybe around 100 ft or so - as the graphs scale corresponds to 35000 ft or so, but Zooming IN, helps seeing it a bit better, within the limits of the graph resolution, and scale.
The altitude drop coincides with a reduction in thrust - see the N1 Actual Eng1% and Eng2 % graphs - and increased roll - see Roll graph.

2. the Normal Acceleration graph, which if I understand correctlty is a reflection of the Turbulence, shows increased up/down air turbulence activity right at that time.

So, I think, turbulence, drop in altitude (with reduced thrust) and roll, were the factors that the PF was responding too with Roll and NU.

I have a vague recollection of seeing posts tangentially, or directly mentioning the same thing, but can't recall exactly which ones.
Very important point. So...

AP disconnects
a/c at 0 deg pitch => will descend
pilot stick back 3/4 causing nose up pitch 11 deg.
climb rate goes up.
after 4 seconds first stall warning
after 15 seconds altitude has not changed (downdraft/reduced thrust?)

So PF was correct to stick back but he over does it.
Stall alarm sounds, he eases off on the stick pushes it fwd briefly, alarm stops.
Then he resumes stick back to maintain altitude.
Now the THS starts helping PF to pitch nose up.
Now he is gaining altitude with help from THS.

Report #3, Page 111, Longitudinal parameters

Notice the insidious influence the auto THS (cyan) has on elevator position. At some points he is stick forwards (red line, 02:12:17) yet elevators stay around -30 deg (purple). Clearly this would add to the confusion of inputs.

Last edited by xcitation; 4th Aug 2011 at 22:29.
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Old 4th Aug 2011, 22:06
  #1558 (permalink)  
 
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Thanks Spagiola. Using those phrases ("going up"/"going down") sure seems to hinder understanding.
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Old 4th Aug 2011, 22:07
  #1559 (permalink)  
 
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overthewing

Yes, save for your final sentence under (4). This was not the same crew that had flown out, if my memory serves me well (e.g. PF had been on holiday with his wife, without their children, on board the flight).
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Old 4th Aug 2011, 22:11
  #1560 (permalink)  
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I've had some complaints regarding French translations and offensive text. Not being a French speaker, I am a bit out of my depth with such problems as, to quote the saying, "it's all French to me".

If you have a problem with French text as posted, by all means send me a PM with details.

Due to the present day job workload, I am a little behind in my monitoring of this thread. I expect to catch up in the next few days.
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