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Old 10th Jun 2009, 14:10
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Disclaimer: I am not involved in any aspect of flight aside from being on occasional SLF.

I've been reading this thread for quite some time now and, aside from the obvious non-informed conjecture, have found it truly informative. Again, I applaud all you professionals who take to the air currents!

One thing I have not seen mentioned which I want to throw out (again, as an uninformed member of the seated public) is some references I have seen to incidents with the 300-series of uncommanded nose-down issues.

could this possibly be related to AF447??? It would seem to me that if
the aircraft entered a nose-down profile whilst entering, or within, extreme
turbulence then this might have an adverse impact on flight control???

Again, it's merely conjecture on my part which I'm throwing out to you professionals.


Last edited by rgbrock1; 10th Jun 2009 at 14:32. Reason: Improve verbiage
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Old 10th Jun 2009, 14:12
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ONLY the CVR (if ever recovered) can give a conclusive answer as to whether the flight crew attempted to make an emergency transmission or not!!!
Not entirely true. The FDR records Mic Keys to the VHFs. Any Mic Keys following a significant recorded failure would be, almost certainly I'd say, distress/May Day.
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Old 10th Jun 2009, 14:15
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Captainflame, can you give me the link for the Air Caraibe incident? I don't mind reading in French.

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Old 10th Jun 2009, 14:37
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the confirmed turbulence message was reported by Brazilian ATC as mentioned during the last radio contact.

I may have to take that back as "confirmed" as I also can no longer find a reliable source. Unfortunately no time now will come back to it though.
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Old 10th Jun 2009, 14:37
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HF Also

Forget: "Not entirely true. The FDR records Mic Keys to the VHFs. Any Mic Keys following a significant recorded failure would be, almost certainly I'd say, distress/May Day."

The FDR also records HF mic key events, which would have more likely been used.

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Old 10th Jun 2009, 14:40
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BOAC said
Indeed, Jetstream - (welcome to the fray!)
This is too much.
This thread has seen more than half a million hits.
At an average of 3 views per day per person for a week, that suggests that about 20,000 people are viewing.
Do you have any idea how many of us are exercising supreme RESTRAINT by NOT posting? So that there is some hope of the thread being useful and informative ?
Literally thousands of us are just as intelligent as even those that post sensibly, hundreds of us I am sure just as aviation-well-informed and knowledgeable. At least dozens of us equally knowledgeable even on the specifics.

We too can see inferences, postulate connections, wonder at possibilities.
But we DONT POST unless we actually have something to contribute.
Even if we come close to posting, we use the SEARCH facility and in almost every case discover the five or six times our question/idea has ALREADY BEEN DEALT WITH? - so we don't.

Unless I am mistaken, you are in your quoted post, BOAC, WELCOMING a PPL with one (non-contributory, already discussed about three times) post to his name to JOIN THE FRAY. And INVITING this person's thoughts on the main issues ?

Shall we ALL join the fray with all our little repetitious puny thoughts and observations ? Shall I ?

Don't you see, that would destroy the threads usefulness entirely ?

PLEASE, everyone try hard to discourage either yourself or others from posting unless you/they have a real, novel contribution to make.
The poor mods are run of their feet, and reading it all is almost more than i for one can manage. If you go on like this, the mods might just throw in the towel and then where will we be?

My suggestions

1 DONT POST unless you have something novel and useful to contribute either to facts or logic. Don't need certainties, though - probabilities are Ok - intelligently weighing probabilities is the name of the investigation game.
2 DONT POST without first conducting a skilled and intelligent search for prior relevant postings, even if you have read the lot, and CERTAINLY if you haven't.
3 DONT POST your feelings, hopes, fears, puzzlement.
4 DONT POST your comments and reactions to the style of other peoples posts. Posting to point out a useless post also just doubles the mods deleting work. It has been suggested that pressing the alert button is better.

In essence, please show RESPECT for the huge SILENT MAJORITY who are exercising excellent self-restraint. By trying to emulate us.

Now, of course, this post totally violates suggestion 4.
Please don't do the same by commenting on it. Let the mods just remove it without having to remove its children too.

Sorry, I have so many times refrained for posting my own puny little thoughts and conjectures and reactions - to have other people endlessly cluttering up my information source because they can't do the same finally made me FLIP !!!!!!

Count to ten before hitting "reply"? Pretty please ?
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Old 10th Jun 2009, 14:42
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ELAC, as to

@ 210T and M.80

Optimum Altitude = FL360
Max. Alt. @ ISA+20 = FL370
Max. Alt. @ 1.4G Margin = FL378
Max. Alt. @ ISA+10 = FL385
Max. Alt. @ 1.3G Margin = FL394
the numbers for AF447 / MSN660 are slightly different (lower MAX ALT):

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Old 10th Jun 2009, 14:57
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Now don't be silly... The PIC of 587 overcontrolled and drove the yaw oscillation to a destructive degree - FACT

Well, there you go, and all this time I thought it was the co-pilot who was flying at the time and initiated the rudder inputs.

Actually Parabellum you were quite correct. The SIC was flying AA 587 when it went down, not the Captain. This may be a repost however. Could of responded earlier but there are several hours difference over here on the other side of the pond.
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Old 10th Jun 2009, 15:01
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Cockpit reported turbulence

Concerns Over Recovering AF447 Recorders | AVIATION WEEK

Mr Arslanian, for those fairly new, is the head of BEA...the French aviation investigation board similar to the US NTSB.

"Data still is limited, Arslanian says. The aircraft departed with no known faults. In the last received communication from the flight deck, the pilot reported turbulence about a half hour before the aircraft is believed to have been lost."

Now..both Brazil and Senegal report no VHF with the aircraft...and it is not mentioned how this message was received by AF but the suspicion is that it was a cockpit generated acars using satcom. The question a lot of folks would then ask is why isn't on the list of acars messages posted thruout this thread...? The answer to that is that those messages posted were Maintenance messages...using the same basic system but routed to a differerent AF user. For instance we have not seen the routine acars messages the aircraft would normally receive and generate such as weights, out times, off times, position reports. and text conversations with dispatchers.... which always occur. I am sure AF and now BEA and probably Airbus have all those messages...they are just not out in the press.
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Old 10th Jun 2009, 15:01
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Muhaha S.F.L.Y. your are right!

Ladies and Gentleman we have ahead new terrorist type which wait for a CB area with severe turbulence, in the middle of the Atlantic Ocean after 4 hours into the flight to get exploding a bomb on board, but, before do that, they disconnect a Toilet Waste Vacuum, then make a trick to the pilots disconnecting A/P, A/THR, not joking enough they also disconnect ADIRU-2, ISIS-1/-2, then cut out TCAS Wires, operate to fail all Flight Controls Computers and keep pilots busy by an ADIRU the end kick a door to get pilot advised by CABIN V/S chime and then, last but not least, Boooom....take exploded! Obtaining to make a hole in the middle of the Ocean putting 228 people and a faitsful of wreackage 6000 m down the water!
Your fantasy is without boundaries. Try with Diseny or Pixar...they are looking for people like you.

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Old 10th Jun 2009, 15:10
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Graybead, PJ2

In regard to the 2:14Z advisory on the Cabin Pressurization Controller, are we looking at a real event or, given the depence on ADIRU input (as visible in PJ2's AOM excerpt, THX!), just at a consecutive error resulting from the loss of consistent air data?

Graybeard's TCAS analysis brought me on this track.

Don't have access to the A330 AMM, therefore can't decode (below ATA chapter level) what the 2:14Z error code means in detail.
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Old 10th Jun 2009, 15:20
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What I was suggesting is that it is a possibility. In my career when I was a first officer (BOAC) I have operated in heavy crew situations where the captain indeed would go back to the bunk with instructions of not to be disturbed unless absolutely necessary. If the crew thought they could penetrate the line they may not have disturbed him. What followed next probably precluded him coming up anyway. And there are certain pilot types who would prefer not to disturb him on principle. It is dangerous to disgard a possibility just because it it not something either I or you would do
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Old 10th Jun 2009, 15:23
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the last message was a Pressurization Controller Fault as stated by A330 AMM...which can means both of your theory. I'm propending for the Pressurization Controller erroneus input by ADIRU.

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Old 10th Jun 2009, 15:29
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"The ACARS also contains protocols to support retry of failed messages or retransmission of messages when changing service providers."

Interfug asked if it's a complete list, So: How often does it retry? We know it got off what? 27 total faults and warns (including 3 mtc status wrns) for four minutes straight, so the acars system had normal DC and was functioning. I don't see how there could be any missing messages between 0210 and 0214z since ACARS breaks the info up into blocks (where's AVspook?, he probably knows the answer to this) This is the world of data bits and verification and secondary resends: only a real "TRON" can verify that when it's got a lock it's streaming fast. Wiki only says:
Its can be programmed for number of retries - This is the VHF ACARS they are talking about, on some AB's will ahve a dedicated provider eg SITA however you may alos have the option to swicth to another provider (Arinc) however it will keep interrogating the SAT until it offload its message.

The company i worked for the VHF had 3 goes at offloading the ACARS before switching to SAT , It figured if it missed 3 offloads it must be out of range of a Line of site VHF station & then switched to the more expensive SAT option.

No HF mesgs - no hf fault same for engines same for Inertial Data from the ADIRU teh ACARS Hit the SAT... It knew where the aircraft was (lat long) it knew where to find the SAT and it beam steered the Antennae to get that hit

at the Maintenance center for both Boeing (Aircraft Health Management option) and airbus (AirMan Option) the messages will pop up allowing access to order parts send repair info to the arrival station while the aircraft is in flight. The LAT/LON of the aircraft also used to show on the screen and on the AirMan option you could view a realtime globe of your fleet
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Old 10th Jun 2009, 15:38
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ACARS Data collection & Offload Description

Good description can be found here

Boxes which have detected their own failure set 3 bits on the Sign Status Matrix The SSM of the ARINC 429 word which Indicates FW Failure warning of the Box

Boxes which are non operational have failures reported by downstream boxes ( lack of incoming 429 data would be an example)

Note If The recovery teams can get the QAR they will have far more data than is presented on the FDR - If AF had the QAR option
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Old 10th Jun 2009, 16:45
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ACARS tranmission was via satcom

Finally - i am glad, that avspook maybe closed the discussion how ACARS messages were transmitted.

I have 3-4 years of expierence woking with HF data trans. and 2-3 years on SATCOM.
So, VHF is limited in range - useful on ground.
HF - not an option. As some documents are stating, it is an option close to poles - where SAT signal is week and angles to sattelite close to 70 deg.
What is left - SATCOM.

Minimum SATCOM link bandwith is 16 kbps - all known ACARS data can be transmitted in 1 sec. SATCOM modem also can take responsibility to repeat data, if not send propertly, so only 2:14z events data can be incompleted\not fully transmitted.
Looking at AF447 antena location, i also can gues, that SATCOM equip. was high power-small antenna-wide beam, antenna can be pointed to geo satelite with 15-20 deg. accuracy and still works.

That also means that at 2:14z the plane very likely was in one piece, airframe intact, and antena pointing to SAT with 15-20 deg. accuracy. If pointing devices were working - pitch\roll angles likely not exceeding 60 deg. It hardly believable, that plane broke apart, but antena was not torn apart from pointig device, and still recieving data and power.

Now - very very speculative part:
SATCOM modem is allowed to transimt data only in its 'time frame'. (to avoid signal inteference with other ground transmitter at geo sattelite end). Time frame is very narrow and very precisely calculated, so if you move antena 100 meters close to the sattelite (because of altidude, air speed, round globe) it is detectable - signal arrives a little bit to early\late. (i was told that SATCOM operators can notice even if i move antena 100 meters on the ground)
If logged, delay data can be used in reverse ingineering - to calculate distance from sattelite to AF447 and can provide coordinates with 100 meters distance (hardly more than 1-3 kilometers on map) accuracy. But only if logged. Signal/noise ratio (S/NR) can give some idea how precisely antenna was pointed and indicate that a/c was not expierencing wild changes in pitch\roll.
Maybe this helps to close some speculiation.
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Old 10th Jun 2009, 16:58
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10/06/2009 - 10h34
Press Release- English


The Brazilian Navy Command and Aeronautical Command inform that until this moment that a total of 41 bodies have been rescued, 25 of these are aboard the Frigate Bosísio.
The first 16 bodies recovered, which are in Fernando de Noronha, will be transported by a Hercules C-130 aircraft to the Recife Air Base this Wednesday, June 10th, in the afternoon.
The search and rescue activities will continue during the night, as has been the norm, and will be concentrated at the spots where bodies have been located.
The French Government has requested entry, into Brazilian territorial waters, of two seagoing tugs contracted by France: the Fairmount Expedition and the Fairmount Glacier, that will bring with them 40 tons of equipment to aid the search for wreckage. In addition, the Nuclear Submarine Émeraude, the Research Vessel Porquoi Pás and the Amphibious Assault ship Mistral, are on route to the search area, in coordination with the SALVAERO Recife.

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Old 10th Jun 2009, 17:00
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The English text below is an automated translation of the press release at the bottom (as officially distributed):

Translation: Portuguese » English

10/06/2009 - 10h47
Note 1 - 09.06.09 (PF / IML-PE)

Federal Police and Department of Social Defense of Pernambuco

The Federal Police and Department of Social Defense of Pernambuco, by the Legal Medical Institute, announced that the redemption of the first bodies of victims of Flight 447 of Air France start joint work of identifying them.

The procedures expert will begin on the island of Fernando de Noronha, where three federal experts, a federal papiloscopista a coroner of Pernambuco and one assist to carry out a visual inspection autopsy, collection of genetic material (DNA), collection of fingerprints and cataloging bodies, clothes and objects redeemed together to each victim.

After this first analysis, the bodies are carried to the IML, in Recife, where medical examinations will be made legal. The examination of DNA, when necessary, will be conducted in the laboratory of the federal police in Brasilia.

All the staff involved in this work of identification of victims deeply regrets this tragedy and ensure that family members will provide expertise to work full speed.

By: Federal Police and Department of Social Defense of Pernambuco

Tel: (61) 2024-8142

10/06/2009 - 10h47
Nota 1 - 09.06.09 (PF/IML-PE)

Polícia Federal e Secretaria de Defesa Social de Pernambuco

A Polícia Federal e a Secretaria de Defesa Social de Pernambuco, por meio do Instituto Médico Legal, informam que com o resgate dos primeiros corpos das vítimas do vôo 447 da Air France iniciarão um trabalho conjunto de identificação dos mesmos.

Os procedimentos periciais terão início na ilha de Fernando de Noronha, onde três peritos federais, um papiloscopista federal, um médico legista de Pernambuco e um auxiliar de necropsia realizarão a inspeção visual, coleta de material genético (DNA), coleta de impressões digitais e a catalogação dos corpos, vestimentas e objetos resgatados juntos a cada vítima.

Após essa primeira análise, os corpos serão encaminhados para o IML, em Recife, onde serão feitos os exames médicos legais. Os exames de DNA, quando houver necessidade, serão realizados no laboratório da Polícia Federal, em Brasília.

Todo o corpo técnico envolvido nesse trabalho de identificação das vítimas lamenta profundamente essa tragédia e garante aos familiares que será prestada total celeridade ao trabalho pericial.

Por: Polícia Federal e Secretaria de Defesa Social de Pernambuco

Tel.: (61) 2024-8142
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Old 10th Jun 2009, 17:08
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You have a confirmed message from the crew that they were in turbulence
What is your reference to write that ?
:: FAB - Força Aérea Brasileira ::

In the estimated timetable for the position TASIL (23h20), the aircraft's AIRFRANCE not made contact with the radio set CINDACTA III, which was reported to the Control DAKAR.

The Company informed the CINDACTA III AIRFRANCE at 08h30 (de Brasília time), that approximately 100 kilometers of TASIL position, the AFR flight 447 sent a message to the company informing the aircraft technical problems (loss of pressurization and failure in the electrical system) .

At 02h30 (de Brasília time), the Recife SALVAERO triggered the search for the means of the Brazilian Air Force - FAB, with 01 C-130 Hercules aircraft, 01 P-95 Bandeirante for maritime patrol and rescue squad Aeroterrestre (Paras)
"de Brasília time" do they mean Paris time?
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Old 10th Jun 2009, 17:14
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After this first analysis, the bodies are carried to the IML, in Recife, where medical examinations will be made legal. The examination of DNA, when necessary, will be conducted in the laboratory of the federal police in Brasilia.

Correct translation would be "where legal medical examinations will be carried out".
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