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AF447

Old 11th Jun 2009, 03:25
  #1121 (permalink)  
 
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Air France hits bad weather

Tonight, French TV TF1 has broadcasted a testimony from a Air France maintenance manager explaining that the pitot tubes issue was well known at Air France and shown internal documents stating that several critical problems has already occurred on AF CDG-NY as well as AF CDG-TOKYO
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Old 11th Jun 2009, 03:31
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Boac, yes, well in that case, only these two:

The PFD flag at 210Z was an "airspeed limit" warning (error code 2283)

The PFD flag at 211Z was a "flight path vector" warning (error code 3412)

fell into the definite bin.

These results were passed along via an exchange of emails so I will try a prearranged phone conversation to see what else can be made more solid in the list.
On the "prototype airliner", the A300, Flight Path Vector, is a PFD presentation that can be selected on the glaresheild to predict on the Attitude Display where the mass of the airplane is going to wind up. You "Fly the Bird" target and it helps you manage energy. I know it would likely be a cascading failure from either the AIDRU, airspeed data loss, or the IRU portion itself. Is the A330 the same?

(A330/340 drivers are amazingly silent today...)
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Old 11th Jun 2009, 04:04
  #1123 (permalink)  
 
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Shocking

Maybe they've had a gutfull, CC.
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Old 11th Jun 2009, 04:37
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Crossbleed said:
Shocking
Maybe they've had a gutfull, CC.
Yeah, maybe you're right CB!

We have been pretty hard on their airplane, and most of us have no clue how it actually works. As a matter of fact, some of the guys I flew with on the original glass bus had no clue how it worked!!! New checklist and procedures would come out every six months, and we had to re-learn everything all over again.... This went on for seven years. But to the guys who memorized the architecture of the systems things were not so mysterious.

Late model glass is extremely complicated and the only way I know to coax the real experts to come out and play is to float trial balloons and see if they get shot down or not.

TWO major corrections to my posts. "Selfin" has pointed out that I'm wrong about the toliets. It was this flight and the date rolled over.... duh... and it was a 06 flight code.... me sorry, Thanks Selfin.

Secondly, the last SITA(acars) position is theoretical at this point. I guess it came from Tim's extrapolation of the last positive position at 0133z. However the last 0214z SITA Sat transmission (not AF) must have a lat/long in the original uplink code or it wouldn't exist.

Also, I noticed, there were big ships hanging out at those coordinates for several days after the accident, ships

so maybe we're not the only ones who think that's the likely spot. What we need is a French TV screenshot of the SITA(acars) report to AOC, about turbulence claimed to have been sent by Air France PR at 0200utc and a SITA trans position at 0214. Dam things encripted, so we're going to need a hacker or a leak

CC - going back to the blue room, you got it.

.

Last edited by Captain-Crunch; 11th Jun 2009 at 07:11. Reason: changed from most to some I flew with
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Old 11th Jun 2009, 05:06
  #1125 (permalink)  
 
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PJ2,

Thank You.

Unfortunately, the lav thing is going to keep cropping up.

Here's the deal for the unknowing:

#1: The message may be considered spurious, the VSC has forgotten how many lavs are attached or where they are. Everything still works.

#2: The toilet system is a vacuum system. Below 16000 feet, there is a vacuum generator back at the waste tanks which creates the suction to remove the effluvia. Above 16000 feet, the job is done by differential pressure.

#3: When you press the flush button, the vacuum system controller takes a quick peek to make sure no other toilet is flushing and if the answer is no, the flush valve (a guillotine type valve, best description, sorry) slides open and voila! If the answer is yes, it delays your flush until the other flush is complete. That's all.

#4: There are no "flush motors" behind the toilet. Nothing dangerous or scary there.

#5: If the vacuum generator still manages to run above 16000 feet, the cockpit will receive many many calls from the gals because the floor will vibrate beneath the floor of the aft galley.

Now that EVERYONE knows how the toilets work, can we move along and try to figure out how a perfectly good airplane managed to find itself in what has to be considered the worst possible weather to find oneself in alternate law?

It's obvious from the ACARS data that they lost more than one ADR. This begets a cascade of failures that are a RESULT of the ADR loss. There is no indication that the failures were independent.

Failure messages are not necessarily chronological. Deciphering the ACARS data is a skill, a black art if you will. Some would troubleshoot the lav faults. Others may look at other faults.

Some have suggested that the crew kicked the tail off.

When the RTL goes, it freezes (hard) at the moment of failure. The range is 31.6º ≤150 CAS to 4º ≥ 350 CAS. Figure the speed when the failure occurred and imagine having enough authority to damage the tail from there. As previously stated, you do get it back at slat extension.

What's left?

TCAS goes with the loss of all 3 ADR's or IR1. If you can get IR1 to work in ATT mode, you can get TCAS back, but not if you are missing 3 ADR's.

How did that happen?

The NAV ADR DISAGREE message.

The message is triggered by the PRIMS either because YOU switched off an ADR and the PRIM(s) detected a difference between the remaining two, or the PRIM(s) detected an error in one ADR and disregarded it.

The A/P and A/T messages?

This warning is displayed only for involuntary disconnection. That will happen when you lose your air data.

Last but not least, the pressurization message. When you lose all three ADR's you lose CPC 1 and 2, so cab press is manual.

Imagine yourself in monster turbulence, lots of red messages in front of you, possibly getting your head knocked on the panel. Are you worrying about cabin pressure?

Is anyone detecting a theme here?

Apologies if I ranted too long or appear snarky, but I'm just saying...

PB
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Old 11th Jun 2009, 05:06
  #1126 (permalink)  
 
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Edit: @ Plastic Bug - It appears we have posted simultaneously. And on the same subject as well.

@Grounded101:

Most transport category aircraft I am familiar with have a panel (usually aft) for cabin crew to monitor potable water & waste tank levels. I don't believe the A330 has a cockpit annunciator for waste/water faults although the the MCDU screens can probably show status.

A VSC/LAV fault related to cabin altitude would be detected after the cabin pressurization system picked it up because the LAV system requires a much lower pressure difference to operate.

@Captain Crunch:

re: Advisory vs Warning. All of the messages other than Maintenance Status messages were either one of the two categories.

It seems a very remote possibility that the crew was completely without ATT data. Loss of air data, specifically airspeed (to a lesser degree altitude) seems to be where all of the clues are pointing.

Who knows, you could be right and if so, that would be a tough nut to crack at night over water IMC or not.

Thank you for the praise but it is undeserved on my part. It is not my sole analysis. I have assistance and will pass along the kind words. The more we look at the data, the more perplexing it becomes.
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Old 11th Jun 2009, 05:27
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It's been more than 24 hours since I posted on this thread so I hope that I'm not overloading it with me-too stuff.

I may have missed it (I do read every post) but do we have knowledge (plots etc.) of where the seats, bodies, Vert Stab and lavatory door were found in a debris field?

I do feel (based on historical experience) that it is unlikely that turbulence by itself would initiate a breakup of a modern large jet. Thus as allways I think that it is important to keep in mind the possible pilot actions in alternate law.

I'm not much of a fan of characterizing out-of-cockpit crew members as critical to an analysis and/or speculation of theories. Pilots qualified to be in the cockpit should be expected to behave in a consistent manner according to their training regardless of seniority.

After we have gained some more factual information about what happened maybe then we can talk about knowledge based pilot experience.
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Old 11th Jun 2009, 05:33
  #1128 (permalink)  
 
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VAPILOT,

No sweat,

The CPC couldn't care less what the VSC was doing. They don't talk to each other. The switch from vacuum generator to DP is done by a 50 cent pressure switch, so nothing there.

I'm telling you man, air data was gone, for whatever reason.

Everything else is eventual.

PB
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Old 11th Jun 2009, 06:47
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Plastic Bug

When the RTL goes, it freezes (hard) at the moment of failure. The range is 31.6º ≤150 CAS to 4º ≥ 350 CAS. Figure the speed when the failure occurred and imagine having enough authority to damage the tail from there. As previously stated, you do get it back at slat extension.
Is there theoretically the possibility, that the RTL got a wrong - much lower - CAS/TAS before it froze?
How does the system work, when data degrades gradually, not instantaneously? Is it possible the RTL got the wrong CAS before it got no CAS at all and froze?

Last edited by Interflug; 11th Jun 2009 at 07:11.
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Old 11th Jun 2009, 07:48
  #1130 (permalink)  
 
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ACARS via Satellite

I work for the subcontractor manufacturer of the major players and we make Inmarsat Classic Aero H+ SATCOM equipment. Here is how it works.

The SATCOM locks onto the P channel signal (600/1200/10500 bps - its dependent on what the network broadcasts and the antenna type) coming from the ground network. This provides the timing reference.

When the SATCOM wishes to log onto the network, it sends a R channel burst (600/1200/10500 bps again dependent as above) to the network using random slotted aloha (and repeats if it does not get a response signal unit back).

When it wants to send an ACARS message, it uses this R channel burst to request resources from the network. The network allocates a timeplan to the terminal, and it then sends slotted T (600/1200/10500 bps) channel bursts on a network controlled frequency to the ground. The size of the bursts are 19 bytes each, so many will be needed to send an average ACARS message.

If the pilot wishes to talk to the ground, then the R Channel mechanism is used to ask for a call setup, then the network assignes a pair of C channels (8400bps), one in each direction, and another tranceiver in the box is turned on to pass voice. 1 or 2 C channels can be supported per plane. The MCDU is hooked up to the SATCOM unit (SDU) and a menu is presented to the pilot from the SDU to allow them to select who to call - the menu is aircraft specific.

Hope this helps.
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Old 11th Jun 2009, 08:05
  #1131 (permalink)  
 
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Crew rest

Do we know what was the rest time the crew had before the flight?

The flights that I did crossing the Atlantic back East, were the most tiring
because it was never easy to get enough sleep although we used to have
minimum 48 hrs rest before flying back.

Can the GPS data be used to establish which ADR is working correctly,
because GPS ground speed is very accurate and will give a very good
reference to which ADR is working correctly?
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Old 11th Jun 2009, 08:38
  #1132 (permalink)  
 
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Hi,

If the loss of valid speed data has been the main factor in this accident (ie. leading to this kind of chain of events: pitot ice in all probes -> all ADRs out -> at the same time encountering a patch of warm air (that made the ice buildup possible in the first place) and thus thinner air, placing the acft a few thousand feet higher (aerodynamically) -> speed marginals decreased considerably -> combine loss or airspeed data, AP, A/T disengagement, performance degradation due to warm air, and possible lower airspeed at the onset (to penetrate turbulent air) -> aircraft approaches coffin corner and very quickly ends up in a high altitude upset / stall because piilot unable to keep speed on the safe side regardless of proper CL PWR + 5deg ANU procedure.)

Consider the above for a moment.

Now my question is: Would the backup speed scale (Pg. 19 -> http://www.smartcockpit.com/data/pdf...able_Speed.pdf) have been complately reliable in assisting dealing with triple ADRs inop and flying without any kind of speed information available? As it's providing guidance through AoA, it should be reliable, but does anyone know if the AF jet was equipped with BSS ?

rgds,
Tero

Last edited by teropa; 11th Jun 2009 at 08:54.
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Old 11th Jun 2009, 08:54
  #1133 (permalink)  
 
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I work for the subcontractor manufacturer of the major players and we make Inmarsat Classic Aero H+ SATCOM equipment. Here is how it works.
Thanks for the insight.

Do you know if AF used Inmarsat, or did they use another provider, e.g. Iridium?
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Old 11th Jun 2009, 09:04
  #1134 (permalink)  
 
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Route deviation

I deviated over 100NM for exactly the same reason.
I transmitted on VHF to others around before telling ATC.

On 447 ...there must have been something wrong and accumulating.
Lets hope we (or the sub) find the boxes.
Joe
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Old 11th Jun 2009, 09:45
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VTP

The Brazilian Navy has some photoes of the recovered tail

https://www.mar.mil.br/menu_h/hot_si...bus/index.html

(see under fotos)

They also have a diagram of the debris field updated on the 9th saying that it's a 46km radius, but that bodies have been found over 85km apart. Saying that there's no specifics for when the bodies were recovered so it's dificult to identify if it could be down to drift.

The tail section detail is not sufficient to identify if any of the lugs on the fin box have been sheared, though there does appear to be a large grey section of structure below where the attachement points would be. This suggest that any structural failure was not in the VTP itself but in the fuselage structure below this.

What I can't find is a picture of the Fin box for the A330-200 as produced in Stade, the only image on EADS is of a A320 box and I'm not sure if the attachement points are common. It does look quite different to the pictures of the AA587 damage http://www.ntsb.gov/publictn/2004/AAR0404.pdf.

This doesn't explain how the tail may have seperated, but should shift some of the focus to the rear structure, which I believe is metal on the A330.
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Old 11th Jun 2009, 10:17
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Question

I just wonder, if we know for sure that the 02:14 msg was the last one; it isthe last one on a page, I have not seen the next page; am I right the acars list was just a leak, no official info?

And just a question for somebody who might know. Am I right that adiru is just a signal processor? And the processed data from the sensors are going from adiru to the flight control comps?
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Old 11th Jun 2009, 10:19
  #1137 (permalink)  
Cool Mod
 
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Please!!

The amount of repetitions, of charts, reports, wx and particularly pictures causes us overworked mods heaps of extra work because they clutter up the thread.

So, before you post any the above do check the thread to see if they are already on show. I can tell you that 9 times out of 10 they are!

You have only 8 days or so to check over and in some cases just one or two.

Thanks.
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Old 11th Jun 2009, 11:38
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The French secret service is investigating whether two passengers on board the doomed Air France 447 flight had links to Islamic terrorism. It raises the possibility that the crash was not an accident.

I really hope they find that box soon,,the speculations starts getting far out of control it feels
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Old 11th Jun 2009, 11:44
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my tuppence half penny....

the aircraft entered an area of severe convective thunderstorm activity skirting the ITCZ.
severe turbulence was encountered as they deviated?
sat's rose from say ISA+10 47C to an incredible 0c
the aircraft at current weight and temperature now cannot maintain current alt
severe icing is now encountered as supercooled water droplets are now super warm as the aircraft is engulfed in ice...wings as well folks. The leading edge was probably destroyed from ice.
aircraft now descending into a TZ( unable to maintain alt)
probes ice over....all the warnings begin
crew try to maintain control with no airpseed, numerous warnings.
lateral/ vertical loads way above certified limits are exceeded.

This may come across as a very simple way of putting it but I have seen SAT's rise along the maritimes to ISA +25 which required reclearances to lower levels as against to what these guys encountered was of bibilical proportions of unrelaible airpseed in a TZ/ sev turb etc etc.....

As for terrorism, I'll think I'll stick with the above. Likewise there is a big runaround going on now changing probes but inreality a ? to our engineers surely any probe would have iced over in the unreal conditions this ill fated flight encountered?
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Old 11th Jun 2009, 12:06
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Cool

Hello,

That's about terrorism ....

Terrorists names cleared by french police ......

QUOTE
PARIS, 10 juin (Reuters) - Les services de renseignement français ont mis hors de cause les deux passagers du vol AF 447 dont les noms avaient paru suspects initialement, a annoncé mercredi le ministère de l'Intérieur.

Deux noms "correspondant à des personnes connues pour leur lien avec le terrorisme islamiste" figurent sur la liste des passagers, avait écrit le site internet de l'Express (LExpress.fr - l'actualité en direct : Politique, Monde ,Economie, Culture, Sport, High Tech, Société, Science, Environnement, Médias et People) en milieu de journée.

Une enquête approfondie a permis de mettre hors de cause ces deux passagers, décédés comme 226 autres personnes dans l'accident du vol Air France reliant Rio de Janeiro à Paris, a dit un porte-parole du ministère de l'Intérieur à Reuters.

Les autorités françaises ont indiqué à plusieurs reprises que l'hypothèse d'un attentat contre le vol Air France 447 n'était pas totalement écartée, même si elle était peu probable.

Elles sont souligné qu'aucune revendication sérieuse n'avait été enregistrée.

Le biréacteur s'est abîmé le 1er juin dans l'océan Atlantique pour des causes non élucidées, sans que l'équipage n'ait envoyé de derniers messages de catastrophe.


Google translation:

QUOTE
PARIS, June 10 (Reuters) - The intelligence services have french exonerated the two passengers of flight AF 447 whose names had appeared initially suspected, announced Wednesday the Ministry of Interior.

Two names "for people known for their links with Islamist terrorism" appear on the passenger list, wrote the website of the Express (LExpress.fr - l'actualité en direct : Politique, Monde ,Economie, Culture, Sport, High Tech, Société, Science, Environnement, Médias et People) in the middle of the day.

A thorough investigation has established beyond question the two passengers, 226 died as others in the crash of Air France flight linking Rio de Janeiro to Paris, said a spokesman for the Ministry of Interior to Reuters.

The French authorities have repeatedly indicated that the hypothesis of an attack against the Air France flight 447 was not completely excluded, although it was unlikely.

They stressed that no serious claim had been registered.

The jet crashed on 1 June in the Atlantic Ocean for reasons unclear, although the crew had sent messages of recent disaster.


Nevertheless .. this statement is ludicrous ...

They stressed that no serious claim had been registered.

When you checkback history of terrorists actions on planes .. :

QUOTE
On 21 December 1988, flight 103 London-New York Pan Am flight exploded in the open and the debris of the Boeing 747 back on the small Scottish town of Lockerbie. After three years of research and 15,000 interviews, the investigators demonstrated that a bomb carried in a luggage container that triggered the tragedy and the deaths of 270 people including 11 people killed on the ground by debris the aircraft. The scenario of the disaster is reconstituted, then suspicion falls on charges of Libyan officials close to the government. Libya's Colonel Gaddafi is bench nations and placed under embargo world.

In France, Judge Bruguière charge of the investigation into the explosion of the UTA DC-10 establishes a similar link with the same authors.

Finally, in 2003, 15 years after the attack, Colonel Gaddafi decided to return to the society of nations and proposes to pay a large indemnity to the families of victims: $ 2.7 billion, or $ 10 million per family. This will be enough to make things in order.


B747 Panam Lockerbie : no claim by terrorists
DC-10 UTA : no claim by terrorists
Air india 182 : no claim by terrorists

Although the terrorist attack seems unlikely, the French authorities in complaisent with absurd and fantasy statements ....

Regards.
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