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AF 447 Thread No. 9

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AF 447 Thread No. 9

Old 16th Jul 2012, 15:17
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Originally Posted by DozyWannabe View Post
I repeat : JD-EE is an electrical and electronic engineer of 60 years' standing. I think he knows what he's talking about.
^^^ " he's "
Umm...

[not sure JD-EE is still around to correct, but see e.g. http://www.pprune.org/tech-log/44963...l#post6437226] ]
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Old 16th Jul 2012, 15:18
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The PNF may have been absolutely wrong. The PF sensed an odor he did not recognize. Having an answer to a question is not sufficient to close the topic if it may have been wrong. JD-EE was not present, thankfully. PF was, and his question got an answer.

You are easy to please, if it matches your goal. I suggest that more common by far are electrical faults, overheated defrosters, motor spark, and hot wiring, than a smell an experienced pilot cannot identify, and wants input from his partner....

Have electrical problems been eliminated by anyone other than you? Not by BEA.

Last edited by Lyman; 16th Jul 2012 at 15:20.
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Old 16th Jul 2012, 15:21
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I'm pretty inclined to accept whatever JD-EE (female) says about electrical matters and the production of ozone. However I suspect many of us will not be able to reliably distinguish the smell of ozone from the smell of an electrical fault/short. A common misconception is that the this "electrical smell" is a result of ozone production. So did the pilots really smell ozone, or did they smell an electrical problem that they (incorrectly) ascribed to ozone? What may be easily distinctive to JD-EE may not be to many of us.

The timing seems suspicious, and I would not be inclined to dismiss an electrical fault just because this fault should not have produced ozone. It might have produced something that the pilots believed was ozone.

At the same time that both pilots suddenly perceived that the cockpit had suddenly become uncomfortably warm. A sudden updraft of warmer air from below, which was sufficiently rapid to temporarily "overwhelm" the ability of the climate control system to compensate? Maybe. Or maybe something else.
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Old 16th Jul 2012, 15:25
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Somehow, I missed JD-EE's post on electrical smells.

As a long-time Hammond Organ fixer (over 40 years), I can tell you that the so-called "electronic smell" is often the smell of:
a) burning/melting plastic (often insulation)
and/or
b) over-heated transformer components, such as wax, oil, and the like.

Ozone itself is a different smell. Lyman's speculation can never be verified as truth or not. We weren't there; we can't smell it. But it walks like a dog, barks like a dog, etc. etc.

OTOH, burning plastic is generally extremely toxic, so now we can add fuel to the fires of speculation: PF was maybe poisoned by toxic fumes(???).

Off to search for JD-EE's post.
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Old 16th Jul 2012, 15:33
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@Lyman, slats11,

The lack of secondary evidence in terms of items recovered, no cascading series of failures consistent with arcing or fire and no reference to unusual smells, temperature changes (or, indeed, smoke) after the initial query leans heavily towards discounting the possibility, does it not?

@Organfreak - you can click the little arrow next to JD-EE's name in my initial quote above and it will take you directly to her post.

Last edited by DozyWannabe; 16th Jul 2012 at 15:34.
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Old 16th Jul 2012, 15:46
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Yes indeedy, DW, and thanks for that. A post from last year; who knew?

And, I meant to include this photo in order to bolster my own credentials:



(I 'spose this will be removed)
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Old 16th Jul 2012, 16:06
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Perhaps Dozy. However so much of this still doesn't quite make sense. I am certainly not insisting there was a electrical fault. But I am wondering if it is possible.

I just find the timing odd. Confusion about whether PNF had adjusted the A/C. An ozone smell. A significant rise in cockpit temperature. And then a minute later UAS and autopilot drops out.

Yes the explanation could be an updraft of warmer air associated with Cb. This could have produced an ozone smell in the cockpit, and may conceivably have resulted in a transient rise in cockpit temperature. No comment about an updraft or turbulence at that time however.

2 h 08 min 27 Its me who just changed to max eh
Any idea what PNF is saying here? Radar??

2 h 08 min 44 its ozone thats it were alright
Was PF worried about something at that time?
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Old 16th Jul 2012, 16:39
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Originally Posted by slats11 View Post
Perhaps Dozy. However so much of this still doesn't quite make sense.
What in particular is bothering you? I've been hanging around these threads so long I could probably dig up some stuff to help.
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Old 16th Jul 2012, 16:58
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I am not sure I would put much weight on an electrical fire situation, on board the aircraft that is. But outside, think St. Elmo's Fire. A quote from a B757 FO flying from LAX to ATL in high clouds:
As soon as we got into the clouds, St. Elmos fire was blasting off the nose of the airplane, the ozone smell was intense.
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Old 16th Jul 2012, 17:26
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Snoop

@Organfreak
The organ of my church is a traditional organ, but for some months "they" did important work of "renovation" (no need !). The air is blowed with an electrical engine, but they connected the whole to... the speakers already connected on an electronic organ...

the organist found something sounded wrong wenn he played the great organ : his nightmares and earmares are finished : the engine burned last week doing much damage in the church...

Nice cockpit !
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Old 16th Jul 2012, 18:25
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I think the problem warranted a look see at the logs of GZCP. Look for squawks, fixes, and any repetitive maintenance. I'll just go find it in the report.


Sure.
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Old 16th Jul 2012, 18:31
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And since when has any accident report contained maintenance logs for the aircraft when there was no obvious maintenance problem relevant to the accident?

Back when we started this merry dance you expressed a desire to make sure the crew were not held solely responsible for the accident if there was any doubt. The crew have not been held solely responsible. What, ultimately, are you trying to achieve now?

Last edited by DozyWannabe; 16th Jul 2012 at 18:32.
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Old 16th Jul 2012, 18:44
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If you think the logs were not gone over with a magnifying glass, you would be mistaken. Are you always satisfied with what is obvious? You do not consider that which may be hidden?

I am not and may never be comfortable with the finding's accuracy.The conclusion is beyond belief. It stretches the imagination that it could be true.
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Old 16th Jul 2012, 18:51
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Lyman, you're confusing the BEA going over the records (which I'm sure they did) with said records' inclusion in the report (which in all likelihood was unnecessary).

What is it about the conclusion that you find so hard to believe? It fits aspects of several previous accidents and known HF problems. Most pilots aren't supermen and even the best are as prone to bad days in the office as anyone. Combine this with organisational entropy on the part of their employer and the chances of something serious happening increase exponentially.

Contrary to the beliefs of some, the BEA have never hidden anything or covered for Airbus, and I'll cheerfully debate anyone who disagrees.

Last edited by DozyWannabe; 16th Jul 2012 at 18:51.
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Old 16th Jul 2012, 18:56
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Cocophony

Hi Lyman,
The conclusion is beyond belief. It stretches the imagination that it could be true.
It makes perfect sense.
All the holes in the Gruyre cheese simply lined up that night.

At time 2.10.03 the flight deck loud speaker warns of autopilot disconnect, and is heard and acknowledged.
From time 2.10.09.6 the Altitude Alert deviation warning "C Chord" sounds and continues to sound until impact.

It is only interrupted by "Stall Stall", ECAM "dings", crickets, "Priority Left / Right", "Dual Input" etc.

No one on the flight deck mentions hearing anything. No one thought to cancel the "C chord".
The only device attempting to warn them that were stalled was lost amongst the cacophony of other aural warnings.

On previous aircraft, we had both the vibrator noise (unmistakeable) and the tactile feel through the control column.
Why was something similar not thought to be necessary?

Last edited by rudderrudderrat; 16th Jul 2012 at 20:29. Reason: cockpit cocophony
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Old 16th Jul 2012, 19:19
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Revisiting the yoke-stick problem

From the final report:
It would also seem unlikely that the PNF could have determined the PFs flight path
stabilisation targets. It is worth noting that the inputs applied to a sidestick by one
pilot cannot be observed easily by the other one and that the conditions of a night
flight in IMC make it more difficult to monitor aeroplane attitudes (pitch attitude
in particular). In addition, a short time after the autopilot disconnection, the PFs
statement that he had the controls and his reaction to the initial deviations observed
(in particular in roll) may have led the PNF to change his action priorities. Identification
of the failure appeared to become a priority over control and flight path monitoring.
Consequently, he was unaware of the climb.
Control of the flight path does not correspond to what is expected. The amplitude
of the actions may doubtless be explained by the highly charged emotional factors
generated by the unexpected autopilot disconnection in the context of the flight.
From the CVR:
2 h 10 min 30,0 Stabilise
2 h 10 min 30,7 yeah
2 h 10 min 31,2 Go back down
2 h 10 min 32,2
According to that
were going up

2 h 10 min 33,7
According to all
three youre going
up so go back down

2 h 10 min 35,2 okay
2 h 10 min 35,8 Youre at
2 h 10 min 36,4 Go back down
2 h 10 min 36,7
Its going were
going (back) down

2 h 10 min 38,5 gently
2 h 10 min 39,3
Ill put you in in A T
T (*)
So .. the PNF made remarks (give orders) to the PF to go back down and the PF give a positive verbal answer
Anyways .. the PNF can't see if the PF make good actions on the stick ...
How he can be sure that his orders are really followed by PF actions ?
By checking the instrumentations ?
Maybe by looking at the instruments and seeing that these would not show what he expected of them (because his order to the PF" back down" and the positive answer by PF) he began to believe that the instruments were no longer reliable
That can be a additional trouble for the PNF ... and alter momentarily is judgement of the situation ..

Last edited by jcjeant; 16th Jul 2012 at 19:24.
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Old 16th Jul 2012, 20:12
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jc, just to let you know:

When I used to teach instruments, and I gave a flight student a correction, I rarely if ever "rode" the controls, unless the student was badly over controlling.

What I did do, however -- and I suspect that the PNF something similar -- was that after I gave a corrective input to the flight student, I watched the flight instruments to see if he put the correction in or not.

In the fleet, I took that same approach when I was a C/P flying with a pilot who was having trouble while flying instruments. I'd make an oral input and watch the instruments to see if he complied with my suggested correction. A number of my copilots did the same for me, and one talked me out of a slight case of the leans.

(Granted, at night near a the deck of a ship, however, I did tend to guard the controls when the other pilot was flying just in case my call for "power" went unheeded, in which case I'd make the input).

Put another way, I'd say that your line on "watching" the controls may not fit with the primary concern that pilots focus on to see if their suggested correction is acted upon or not.

He migh guard the controls, or ride them. Depends.

Last edited by Lonewolf_50; 16th Jul 2012 at 20:16.
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Old 16th Jul 2012, 20:15
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PNF doesn't make any reference to his instruments (other than speed) being out. Remember it was the instruments on his side being recorded, and the report makes no mention of instrument failure. Also, his rising alarm regarding the Captain's return could suggest that he could see exactly what the aircraft was doing and didn't like it one bit.
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Old 16th Jul 2012, 20:17
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Dozy, that does not relieve a copilot from staying in the problem until the Captain returns.

But it does speak to a problem with "cockpit gradient" that we have only a little to work with.
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Old 16th Jul 2012, 21:14
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Cool

PNF doesn't make any reference to his instruments (other than speed) being out. Remember it was the instruments on his side being recorded, and the report makes no mention of instrument failure. Also, his rising alarm regarding the Captain's return could suggest that he could see exactly what the aircraft was doing and didn't like it one bit.
To be simple:
You are PNF in an C172
You see (instruments) that with no doubts the aircraft is climbing
You ask the PF to stop climbing or more you ask him to go down
The PF answer you "yes ok i go down"
Again you check the instruments .. and see that the plane continue to climb .. and of course as nothing indicate an instrument failure .. you become concerned
For the demonstration only (as you can check your own yoke ) .. you check the PF yoke and see he pull the yoke in his stomach ...
In the A330 ...
It was already an instrument failure (unlike in the C172) ... it was a positive answer of PF (like in the C172) ... and when you check again instrumentation .. the instruments show the aircraft continue climbing
You check your stick ?
You check the stick of PF ?
You put handcuffs on the PF ?

Last edited by jcjeant; 16th Jul 2012 at 21:20.
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