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AF447 Thread No. 3

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AF447 Thread No. 3

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Old 1st Jun 2011, 13:30
  #981 (permalink)  
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I am now of the view that the BEA 27 Mai release was bordering on mischievous - almost as if they were looking to see if they could fill PPRune with pages of posts (in which they succeeded).

Why did they miss out the obvious discussion early in the event when the a/c started climbing like a rocket above OPT and probably above MAXALT? Any pilot, even just out of training and on line, would know that that could well be be a one-way ticket to the bottom of the Atlantic, and so where is the "What on earth are you doing" from PNF or "I cannot control the attitude" from PF or whatever? Are we to infer from this omission that
a) It did not happen OR
b) That to tell us is less important than the CVR confirmation that they have duff airspeed, which we already know from ACARS?

What are the BEA playing at?

Last question for AB people - does the reported lack of abnormal law mean a software error here or is it possible the AoA vanes had gone west too? The altimeters/VSIs too? For heaven's sake, was the Pitot heat actually working?
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Old 1st Jun 2011, 13:33
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Another irritating and concerning thing at FL100, when both pulled on the SS simultaneously, I have the bad feeling that they saw the ocean coming close. I think that was just a last try to save something without too much hope.

Back to the technical stuff. AFAIK there is only one SS active at a time. You have to push a button to take over.

Is Alternate Law 2 allowing dual SS input or were they eventually already degraded to mechanical law?
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Old 1st Jun 2011, 13:40
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Originally Posted by MartinM
All I try is to figure out what made him pull after disconnecting the AP.
The right person to answer that would be capt Marvin Renslow as he's the only one known to perform the similar feat. Unfortunately, neither he nor his F/O are able to tell us what were they thinking as their aeroplane pitched up and stalled.

It's debilitating fatigue, suckers!

@BOAC: 1. agree with your view on BEA "report", 2. We'll have to wait for proper report, with full DFDR traces and CVR transcript, to see whether it was simple software mess-up or not 3. pitot heat was almost certainly on - high altitude ice sticks to heated parts, like probes and engine compressors.
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Old 1st Jun 2011, 13:45
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Translating from French means the Captain comes INTO the cockpit but he was no in his seat!
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Old 1st Jun 2011, 13:45
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Hi BluJet,
Originally Posted by BluJet
Your deduction concerning the PF omits that the 800hr F/O was not qualified to fly in the L/Hseat (see first BEAreport). So for me, it could have only been the 32year old, 800hr F/O who was PF.
Yep, I didn't catch that!
About the rudder, I should have expressed something wrongly but I didn't remember what! Then, my intention was obviously not perfectly understood.
Thanks anyway for you nice comments and informative imput.
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Old 1st Jun 2011, 13:53
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How much height would you need to fix it?

PNF took over at 2:13:32 + 15seconds, i.e. 41 seconds before the end and perhaps between 7000-7500 feet.
Even if you did all the right things, when is the latest you can act?
How would that differ if the trim was neutral?

Well, this is Tech-Log
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Old 1st Jun 2011, 13:53
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..If I can make a small contribution to this thread. I have flown the A330 in ALT 2 LAW after a twin ADR incident due to icing conditions. ...
Was this event reported and investigated after landing? Do you have FDR traces that would help understand AF447?
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Old 1st Jun 2011, 13:55
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Originally Posted by MartinM
Back to the technical stuff. AFAIK there is only one SS active at a time.
Wrong. They sum. Google Airbus Sidestick.
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Old 1st Jun 2011, 14:02
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The new report is missing any discussion between the crew related to the stall condition. As written, it appears they did not know for 3.5 minutes that the plane was stalled.

Is that possible?
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Old 1st Jun 2011, 14:11
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@Blujet, takata et al.

With respect to who was flying from where do you now challenge the previous 'agreement' between PJ2 and Lemurian summarized in this old post?

http://www.pprune.org/tech-log/44963...ml#post6452307
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Old 1st Jun 2011, 14:15
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Originally Posted by Capn Bloggs
Wrong. They sum. Google Airbus Sidestick.
They sum *if used together*, this is true. But using the sidesticks together is not normal procedure and the systems will notify the crew with a "DUAL INPUT" annunciation.

Correct procedure dictates that upon passing of control from one seat to the other, immediately following or simultaneous with the "I Have Control/My Aircraft" callout, the stick selector button at the base of the stick is pushed. There is no reason to have two pilots on the sidesticks at the same time.

The evidence so far suggests that but for a second or so, this procedure was followed correctly.

@BOAC : I think the BEA "note" was released purely to alleviate the press "leaks" that were proliferating prior to release. Far better for us internet folks to be speculating with a limited amount of real data (which I suspect is all that they had confirmed at the time) rather than trying to sift through a mountain of press twaddle, don't you agree?
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Old 1st Jun 2011, 14:18
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Originally Posted by paull
How much height would you need to fix it?
- more than that. In my military days it was a given that if you were not starting a successful recovery from a spin (mentioned because of similar descent rates ONLY!) by 10,000 ft you ejected. I suspect it would have been significantly higher for this a/c - 10,000 fpm gives you 1 minute only and I suspect the wings would have come off or the g limited so it would have crashed form 10,000ft. Purely a ball park guess - if a correct attitude change had not been made by 20,000 ft it would be a done deal.
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Old 1st Jun 2011, 14:28
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PNF took over at 2:13:32 + 15seconds, i.e. 41 seconds before the end and perhaps between 7000-7500 feet.
Even if you did all the right things, when is the latest you can act?
We are not told what, if anything, the new PF did after the handover, but the strange thing is that this handover does not appear to have changed much, as vertical velocity at impact (41 seconds later) was still over -10,000fpm.
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Old 1st Jun 2011, 14:29
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Originally Posted by dozy
a mountain of press twaddle
- I have never considered the 'media' here - I am referring to the 'selective' release of inter-crew conversation from the CVR, no doubt, not the media.
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Old 1st Jun 2011, 14:29
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@MartinM, please! Respecting, that non-pilots and even non-experts can add good and valuable inputs to this discussion: Leave answers to questions about technical subtleties of the A330 to the ones who either fly her or know her intimately.

Me, having 10.000hrs+ on A330/A320 am still stunned about what happened there and am still learning a lot of specificities, which I didn't know yet about my aircraft and the environment, I am operating in.

As Regards those who criticise BEA for their restrictive publication-policy:
Having negotiated company agreements regarding data protection for my fellow pilot-brothers in my company and the association:

I pretty much appreciate the strictly factual way they publish: We see what crap newspapers and self-nominated experts already read out of these factual reports and publications. If it was me involved in such an accident, I would really appreciate that it is the real experts, officially tasked by the text, at least spirit of ICAO annex 13, who get the detailed informations, stick to the facts and publish only those after due consideration which explain what happened in order to help making aviation safer.
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Old 1st Jun 2011, 14:30
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@Captn Bloggs: Thanks for the refresher.

There is no obvious advantage to go on dual-input

During normal operation both side sticks are active and associated signals are algebraically added; however, flight control parameters are not exceeded during dual side stick inputs. The pitch control of the electronic flight control system is a load demand system. In clean configuration, maximum pitch up command is +2.5 G and maximum down command is -1.0 G
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Old 1st Jun 2011, 14:30
  #997 (permalink)  
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Originally Posted by robertrbartsch
Is that possible?
- missed the last 50 pages?
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Old 1st Jun 2011, 14:31
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Originally Posted by sensor_validation
With respect to who was flying from where do you now challenge the previous 'agreement' between PJ2 and Lemurian summarized in this old post?
No. At first glance, this is how I deduced that the RHS would be occupied by the FO1 (David Robert) and Blujet shed a doubt on the LHS qualification issue.
From what Lemurian already said, based on AF operations, it was almost certain that FO1 would be PF or PNF (with Captain PF) always from RHS and that the FO2 would take the LHS at cruise as PNF when the FO1 was PF.

This was confirmed by PJ2 also:
Originally Posted by PJ2
Yes, understand - the procedures I am familiar with are the same, except perhaps that for the Relief Pilot position, AF uses First Officers who are licensed to sit in the RHS? Regardless, at some point, the F/Os doing the relief for one or the other two crew members will have to sit in the LHS but this would only be in cruise flight. By your statement I believe you mean that F/O's are not allowed to sit in the LHS for takeoff or landing, and that is the way I am familiar with. The Relief Pilot does not sit in either the LHS or RHS until the aircraft is in the Cruise phase of flight...that would be top-of-climb to top-of-descent.
Consequently, the LHS qualification for this part of the flight should not be taken into consideration: PF could actually have been FO1 (Robert) from RHS with FO2 (Bonin) as PNF from LHS, while the Captain was resting.
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Old 1st Jun 2011, 14:53
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Even if you did all the right things, when is the latest you can act?
How would that differ if the trim was neutral?
If the THS would be in neutral position my gues is that they stood a chance even at 7500 feet MSL. The total velocity unfortunately mostly downward was enough to fly and create lift, if they only where able to get the nose down in the flight pass direction. Sort of in the downward part of a loop. Would not even be a real high G maneuver. They where only in a stall not in a spin.
Unfortunately the THS was still in a 13 degree upward position and if it takes a minute for the THS to get to neutral then they had no chance at all even at 15000 feet.

My 2 cents
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Old 1st Jun 2011, 14:56
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RealQuax wrote:

Me, having 10.000hrs+ on A330/A320 am still stunned about what happened there and am still learning a lot of specificities, which I didn't know yet about my aircraft and the environment, I am operating in.
Sir. As captain of the A330 have you ever yourself experienced pitot tube icing and, if so, what happend and how did you react?
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