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AF 447 Search to resume (part2)

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AF 447 Search to resume (part2)

Old 18th May 2011, 06:59
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Originally Posted by RR_NDB
What you think about LF info yesterday?
LF is equivalent to the National Enquirer? Their sensationalistic claims seem to belong within the latter's frame of reference. (That's especially true given their apparent data input they chewed up and regurgitated in a scrambled sensationalist form.)
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Old 18th May 2011, 07:06
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Originally Posted by machinbird
Wasn't that why there was an extended drying time in a specialized oven before reading the chips? It wouldn't make sense unless they had opened the cylinders and taken out the cards holding the memory chips. I would think that the main thing holding the ocean out of the memory modules was a well situated O ring on an end closure.
I thought I remembered that but I was not sure. I, too, figured it was an O-Ring keeping out the water. But I was not sure if they meant a bakeout without opening or after or both. (Again, I'd have done both. I'd not want to open the mailing tube and contaminate what was inside.)

Actually if it got wet inside I'd expect it to be VERY wet. And semiconductors do not like VERY wet at all. I'd expect the memory to have its own packaging. But that would be nothing to 3900 meters of ocean. If the O-Ring leaked an effective hydraulic machining effect would enlarge the hole and fill the tube. Hence, I suspect it was dry inside. Or else they got heroically lucky.
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Old 18th May 2011, 08:14
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I'm posting this because to me it seems very plausible, plus the source is one I trust and have trusted with my life.

I had a rather enlightening conversation today with said source who from another friend who is in a similarly senior position in a relevant and related business has heard the following, and I paraphrase:

The sequence of events leading to this tragedy appear incredibly trivial: Two young F/O's left at the controls, discussing a two day layover in Rio with a couple of flight attendants present on the flight deck (most PAX asleep), are completely unaware of where they are headed weather wise.

Sad if that's what led up to this, and a serious self management challenge...
 
Old 18th May 2011, 08:21
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Le Figaro replies to BEA ...
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Old 18th May 2011, 08:31
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I had a rather enlightening conversation today with said source who from another friend who is in a similarly senior position in a relevant and related business has heard the following, and I paraphrase:
So lets see

YOU ---------> SAID SOURCE --------> SAID SOURCES FRIEND----------> SAID SOURCES FRIENDs FRIENDs (OVERHEARD FROM ANOTHER SOURCE).

Sounds like a game of Chinese whisper
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Old 18th May 2011, 08:47
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Chris and Mac, thank you very much for that info re the CVR.

ZeeDoktor, how sad if you are right. Somewhat reminiscent of delta 1141.
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Old 18th May 2011, 09:03
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Originally Posted by jcjeant
I dont understand this statement ...

So BEA know where find the plane were the greatest ... but anyways and contrary to this knowledge ... they searched firstly in other aeras .....
No, read the search reports

First they searched in the right area but didn't find anything - why is still unknown, either both pingers failed or the search method failed. They didn't fail due to not looking in the right place - they looked and failed to find.

Then they looked in an area calculated from wreckage drift - not a simple calculation, took a lot of people a lot of work to do it, and it wasn't right. Bad luck - not an easy area of ocean.

Then they went back to the first search area, to look again, and this time found the wreckage
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Old 18th May 2011, 09:26
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Looking at what LF and perhaps others others are now pointing at - let us remind ourselves about the sparse communications & reporting for some time before and 'apparent' flight into what looks like an intense area of the storm (with just a small diversion late in the day c.f. other flights that night).
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Old 18th May 2011, 09:34
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HN39;

Le Figaro replies to BEA ...
There's a fair bit of fancy foot work in that story. How to extract yourself from the s**t and come up smelling of roses! On the other hand, the boot is still well and truely being planted into Air France.
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Old 18th May 2011, 09:41
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@Wannabeflyer: Well it is a rumour forum isn't it... ;-)

Still, I'm not in the habit of posting utter nonsense...

If what I heard indeed turns out to be true, there will be a whole new set of self management and CRM issues we all need to address (not just AF).
 
Old 18th May 2011, 09:45
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Having been doing electronics design since the 1970s I am impressed by the survival of the data.

IMHO, either the memory chips are in a separate sealed module (which can itself withstand great pressure) or the cylindrical capsule did not leak.

If the chips themselves got wet, under the 4km pressure, for 2 years, there would be nothing left because the data is stored in the form of microscopic charged capacitors, and the only protection is the ~ 1mm thick plastic package.

If however the PCB was encapsulated in a suitable epoxy, and this was done under a vacuum to avoid any air-filled voids (which would collapse under the 4km pressure and destroy the module) then the PCB could have survived the total immersion.

It would be interesting to know how these things are made.

It's awfully hard to make a watertight package which can hold 4km pressure for 2 years and which uses just o-rings...
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Old 18th May 2011, 09:47
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Well i for one am glad Le Figaro (and ZeeDooktor's friend's friend friend) has very nicely wrapped this up in very simple layman's terms. This convenient leak has absolved the aircraft, airbus/EADS and AF leaving only the crew to swing. Surprised? I'm not. This 'news' of crew screw up will become the one accepted 'fact' with little attention on the before and after (swiss cheese). The real story is the seconds and minutes before and after initial upset, importantly, why were they unable to recover?

This was not an inexperienced crew, even if their actions lead them in, the real story still lies in what they were trained for and obviously how airbus logic and design works when things go pear shaped. Again, these are billion euro questions and answers that may never see the light of day given we MAY have pilots talking about a weekend in Rio w cabin crew (let's hope some mention of sex was included). Much easier to understand and accept by Joe public who want a sound bite or tweet.

This Le Figaro leak is doing exactly Everything needed by those who have the most at risk....BEA is not obliged to respond w any additional information or answer any difficult questions, AF and Airbus the same. The sooner this 'fact' is spread the sooner the story is accepted and forgotten leaving the crew at fault alone. I hope LF digs deeper and does not leave things as they are.
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Old 18th May 2011, 09:57
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This convenient leak has absolved the aircraft, airbus/EADS and AF leaving only the crew to swing.
Not sure if I agree with that! It seems that the actions of the pilots are directly attributed to AF SOP's...which have been under scrutiny for some time. When all is said and done, IMHO the airline will be to blame just as much as the pilots....
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Old 18th May 2011, 10:08
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Joe public doesn't really care... it's those that stand to sue AIB or AF for an epic fail on their part. Of course those parties have a vested interest.

Occam's razor once again: Complex and rare systems failure vs. inattentive crew cockup. It sadly comes back to the latter time and time again.

The problem needs addressed (and has needed addressed for ages) how to avoid these kinds of mishaps. I fear until we are flying 100% automated from gate to gate, there's always ample room for human error of this dimension.
 
Old 18th May 2011, 10:37
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So a first scan of the DFDR data has not revealed a systems malfunction other than those already known from the ACARS messages, at least not one that requires immediate action;

So the BEA is going to have a look at the CVR;

Is that a leak?
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Old 18th May 2011, 10:53
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@ Katlpax (and others)

About the "Leaker) - He was interviewed on TV recently, partly to boost a book he has written whose main theme seems to be to attack Air France as being a creaky organisation with a lot of "old school" people on board, resistant to change and anything which might possibly weaken their own position.
Thus, he seems to have been tempted to use the "Nothing to Report" telex from Airbus to announce that, therefore, the AF crew must be to blame, because of failings within the airline. (And to get attention for his apparently tendendtious book).
No wonder the BEA was incensed.
Personally, I thought Le Figaro was one of the more reliable papers, but then, I haven't read it for a long time. Other papers seem to have held their horses, and rightly so.
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Old 18th May 2011, 11:21
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I note Figaro's graphic borrows from the BEA interactive where one could see the routings of other planes that night. However, for reasons known only to the BEA, the BEA no longer references LH507 which preceded AF447 along the UN873 airway by 20 minutes, nor (if I recall correctly) does the interactive include IB6024 which followed AF447 on UN873 by 12 minutes. Instead, the BEA interactive mostly plots flights on a parallel airway over a 100 NM distant.

Both the LH and IB deviated off the track because of the weather, and one would think their deviations would be the most relevant to what AF447 did not do. The benign explanation for the 'disappearance' of LH507 and IB6012 from the BEA reports is that their experience, including the communication they had with ATLANTICO, is directly relevant to AF447, and the BEA does not want to describe or discuss it further at this time.
___________

The five questions center on the actions of the crew and AF procedures.
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Old 18th May 2011, 11:30
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It's awfully hard to make a watertight package which can hold 4km pressure for 2 years and which uses just o-rings...
4km is about 6000psi, and according to Wikipedia - Hydraulic Machinery:

Elastomeric seals (O-ring boss and face seal) are the most common types of seals in heavy equipment and are capable of reliably sealing 6000+ psi (40+ MPa) of fluid pressure.
I'm not saying that building one of these memory modules is a simple task, but then again pressures in the 6000psi region are common in hydraulic machinery. I believe the A380 hydraulics operate at 5000psi.

As far as checking if there was water in the module prior to powering it up - would not the simplest way be to weigh it?
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Old 18th May 2011, 11:58
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I don't actually think the Le Figaro reply is of any value and worthy of any attention. I did post that human beings do strange and unaccountable things but I am not prepared to assign blame or responsibility for this incident to the flight deck crew based on what has come out. I am also happy to trust BEAs conclusions - I do not buy any of the rubbish posted about bias, it is just that rubbish. BEA has always been a reliable entity on accident reporting and anyone who believes otherwise is a fool (and no I have absolutely no connection with BEA). When I was young I was taught that patience is a virtue and this is something I continue to believe. Let us wait shall we?
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Old 18th May 2011, 12:00
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ZeeDoktor

Still, I'm not in the habit of posting utter nonsense...

If what I heard indeed turns out to be true, there will be a whole new set of self management and CRM issues we all need to address (not just AF).

The third or 4th hand rumor you posted would fit quite nicely in the Rumor and News section.

However, it won't stand up to technical scutiny until it is connected to the loss of flight control itself.

It simply explains a possible reason for the contribution of weather which has been discussed forever in the old thread.

Since day 1 there has always been the question of possible pilot and aircraft reactions to weather.

The mystery continues until facts are linked.
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