Air France A330-200 missing

[wes_wall]

The report said the pilot sent a manual signal at 11 p.m. local time saying he was flying through an area of "CBs" — black, electrically charged cumulo-nimbus clouds that come with violent winds and lightning. Satellite data has shown that towering thunderheads were sending 100 mph (160 kph) winds straight into the jet's flight path at that time.
Ten minutes later, the plane sent a burst of automatic messages, indicating the autopilot had disengaged, the "fly-by-wire" computer system had been switched to alternative power, and controls needed to keep the plane stable had been damaged. An alarm also sounded, indicating the deterioration of flight systems, according to the report.
Three minutes after that, more automatic messages indicated the failure of two other fundamental systems pilots use to monitor air speed, altitude and direction. Then, a cascade of other electrical failures in systems that control the main flight computer and wing spoilers.
The report repeats a detail previously released by Brazil's Air Force: that the last message came at 11:14 pm, indicating loss of air pressure and electrical failure.

This is what I was trying to get to in my earlier post. It would seem that the ACARS transmitted painted a grim picture of what was going on with the airplane. Since all my flying was in Boeing equipment, and that sometime back, thanks to the info provided thus far, I am beginning to understand the potentially poor conditions during this time frame, and the integrity of the airplane is certainly in question. No doubt, cabin pressure was showing an acceleration in altitude, not a loss.

I also think there is a good chance the airplane may have gone down more intact. An in-flight breakup at altitude would have made for a very large footprint of debris, not what has been found and reported.

[delta092b]

I remembered and dug up the link to the AAIB report in to an A319 that had several electrical failures during the climb out of LHR. I know this isn't the same A/C type or identical errors but it makes you think about the challenges the crew may have had, especially with loss of comms, lighting and having to use visual references to fly.

http://www.aaib.gov.uk/sites/aaib/cms_resources/G-EUOB%202-2008%20Section%201.pdf

[OntarioCopper]

Bomb Threat called in on May 27 for an Air France flight from Buenos Aires to Paris as reported by CNN. Unconfirmed of coarse but one should suspect this is an initial cause until proven otherwise, even if for another destination.

``Air France had received a bomb threat May 27 for a flight from Buenos Aires, Argentina, to Paris, sources in the Argentine military and police told CNN on Wednesday.``

[peter we]

I suspect that they are trying to keep expectations low, as there is a fairly good chance he may be right. If they are actually found, they will look like heroes.

Based on the history of these types of incidents, searchers have been able to find the recorders in circumstances that seem equally difficult more often than not. They also want to find the recorders, since if another similar unexplained incident happens, it would wipe out orders not only for the A330, but also for the A350 and any chance at keeping the tanker program. (Think deHaviland Comet)

The A330 has flown successfully for 15 years or so without loss of life. One going down in a severe storm is no way comparable to the Comet.

[fermented herring]

As usual when airbus and france are discussed there are a number of posts concerning hidden info and conspiracies.

I believe that accident statistics does not provide and statistically significant difference between airbus and boeing aircraft of the same generation (don't know which direction it would point actually).

If this is the case, I assume that all those that suggests that the french/airbus etcetera are hiding info in the interest of the company (nation ...), also suggests that such a behaviour would be able to achieve aircraft with basically equal level safety even if they do not support business practice such as sharing info in the best way to avoid repetition of causes.

Personally, I believe it would be impossible to reach current safety levels if information was not efficiently used to avoid repetion of incidents and accidents.

[Gary Brown]

probe icing
This French publication (in French) is reporting that AF knows of ACARS messages from AF447 indicating icing of the probes. There's an AD for the A330 about this starting from 2001 I believe. Can anyone else confirm the existence of these messages?

AVION D'AIR FRANCE DISPARU : Du givre localisé sur les sondes de l'Airbus A330, actualité Société : Le Point (http://www.lepoint.fr/actualites-societe/2009-06-02/airbus-d-air-france-disparu-du-givre-decele-sur-les-sondes-de-l-a330/920/0/348732)



The source you point to there is saying something perhaps a tad different:

" Ainsi, selon nos informations, sur l'AF 447, des sondes extérieures sont signalées comme ayant givré. Première question : l'excès de glace est-il lié à une défaillance électrique du réchauffage de ces sondes ? C'est très vraisemblable, car, comme nous l'avons écrit lundi, des pannes électriques ont été signalées lors de la dernière transmission automatique de données de l'Airbus, à 04 h 14. (http://www.lepoint.fr/actualites-societe/2009-06-01/airbus-a330-d-air-france-228-personnes-portees-disparues-les-recherches-s-intensifient/920/0/348390)"

"So, according to our information, on AF 447, the external probes signalled that they were iced-up. First question: was the ice build-up associated with an electrical failure of the heaters for these probes? This seems very probable, for, as we reported on Monday, the electrical system failures were specified in the last automatic data transmission from the Airbus, at 04 h 14."

My reading of this is that they are speculating that the electrical system failures on AF447 caused the failure of the probe heaters, and that the probes then reported that the were iced-up.

AGB

[Litebulbs]

I cannot believe that so many people have bet on the complete left field, long shot, outsider, as the cause of this accident. How many times has weather brought a plane down from the cruise? I would suggest that 1000's of aircraft have encountered CB's at altitude over the years, for one reason or another and survived.

What is more likely, something that has not happened before, or some form of mechanical failure, either latent, or caused by something either not doing what is should do, catching fire or blowing up on board the aircraft. That has happened many times and brought aircraft down.

[PJ2]

I thought this thread was about an AF A330 crash, not about sub details and unrelated stories of same, sleeping captains or the continuing unfounded speculation regarding electrical or flight control or pressurization or airframe icing/explosion or airframe failures.

The thread is now repeating itself as new entrants arrive without reading, with their pet "theories" and just plain nonsense. No wonder it's culled regularly.

At this point, nobody, including Air France, even knows the exact lat/long of the accident site let alone the status of the aircraft from entry into the area until disappearance. And if AF or any authority knows, they certainly haven't told anyone here.

We only hear (but have no evidence or confirmation that it is "A330" wreckage) of "pieces" found and a 20km "oil slick".

In the absence of an accident site, the DFDR and the CVR, the only evidence that is certain but which has yet to be released and described here is,

a) the dispatch status of the aircraft under the MEL, (was the radar working, were there any other MEL items?),

b) the exact nature/content of the ACARS messages we are told were received by the airline (and not just by ACARS amateur hackers).

Specifically, what data needs to be confirmed on the ACARS messages are the time stamp of the message, the ATA Chapter reference of the fault, and the exact wording of the fault.

The ACMS and/or AIMS collates and transmits such faults including ECAM messages.

These messages are very specific and targeted for maintenance which then have fault-handling procedures. The messages will, if the aircraft and its systems were capable of sustaining such transmissions, be accurate and sufficient evidence upon which to proceed, again in the absence of an accident site.

Even the path through the satellite-weather images put together and referenced/linked four or five times here is speculative in terms of the aircraft track and timings. We just do not know this information. It is all we have.

[Dysag]

I'll try to keep it simple. Engineers cannot design a plane to withstand the highest loads that nature could ever impose on a structure. Those loads will break the plane.

[Litebulbs]

They have done a pretty good job up till now.

[Flight Safety]

protectthehornet, probe icing and the ACARS reported degradation of the flight control systems could be connected. Besides the electrical busses, the probes are also in common with the ADIRUs and the ISIS. I'll admit however that this scenario requires certain unusual assumptions to be plausible. However consider the possibility of trying to maintain control of the aircraft with degrading flight controls caused by probe icing, in severe turbulence. Since an AD exists for the A330 regarding probe icing, it is a known issue with reported effects and degradation of the flight control systems.

[icevane]

The German news source Der Spiegel just posted an overlay of the A330 track with that of the IR sat image at the time of the accident.

If one where to judge by that, they flew right through the worst CB activity in the region.

[Flyinheavy]

@PJ2:

I agree with what You write,but:

'We only hear (but have no evidence or confirmation that it is "A330" wreckage) of "pieces" found and a 20km "oil slick".'

How many planes are missing at the South Atlantic?

Brazilians are pretty sure about having found the A330

[22 Degree Halo]

Found this

PY0FF assists in search for flight AF-447 | DX World of Ham Radio (http://dx-hamspirit.com/2009/06/py0ff-assists-in-search-for-flight-af-447/)

Appears this radio operator was told to "keep quiet" even though communication was scare at the time. From one of the links translated:

But he upheld the reprimand. The fact is that, having disclosed the recorded conversation between the crew of two Hercules C-130 which were searches, along with an airplane house, had no access to any other communication


:confused:

[wes_wall]

Officials have released some details of these messages, ..... The report said the pilot sent a manual signal at 11 p.m. local time saying he was flying through an area of "CBs"

Why would the Captain do this? A question to those still flying. Do you periodically, or ever, send a manual message to a maintenance center advising in-flight conditions? I know that I might advise center what my current flight level ride was, particularly if it was rough, but I don’t ever recall forwarding such info to flight ops. Now, if damage was suspected or potentially occuring to the airplane, then that’s a different matter. I just find it strange.

[safetypee]

Re ‘pitot icing’ (TAT probe icing) see http://www.pprune.org/tech-log/375784-pitot-icing.html#post4963257
Presumably any TAT anomalies could affect the ADC and ultimately the flight control system. However many of these systems have internal monitors, data cross comparators and validation routines which could eliminate erroneous information, although possibly degrading control system performance.

The links above primarily relate to engine ‘rollback’, which if the particular engine variant was susceptible (always a first time) would be a viable event in the reported atmospheric conditions. However, even with the loss of both engines the aircraft should be capable of flight to a lower altitude where, with improving conditions, systems and engines could be reinstated.

[Lost in Saigon]

"

Why would the Captain do this? A question to those still flying. Do you periodically, or ever, send a manual message to a maintenance center advising in-flight conditions? I know that I might advise center what my current flight level ride was, particularly if it was rough, but I don’t ever recall forwarding such info to flight ops. Now, if damage was suspected or potentially occuring to the airplane, then that’s a different matter. I just find it strange.


It can be quite normal. The message from the pilot would have been hand typed on the keypad and sent to Air France Flight Dispatch.

Separate function from the auto maintenance function.

[greuzi]

PJ2

My personal opinion on the cause of the accident has not been offerred. As I said, the cause of previous accidents was often proven not to be related in any way to terrorism. To promote this theory was not my point.

I simply point out a change in behaviour from a few years ago by the important people in front of the cameras.

To eliminate the subject in the early stages over anything else? They could have picked many possibilities, or denied them, yet they really seemed to promote the idea that a thunderstorm broke up the aircraft.

Our colleagues who fly these machines every day they work now tell us that the theory is at the extremes of possibility.

The irony is that facts are facts, regardless of the reason. Whatever caused this tragedy, your odds of encountering the same problem if you fly on one of these are now considered the same whether freak of nature, a one-off, or anything else. That is why it makes no sense to exclude or promote an idea over another. The statistics of dying remain the same if you are SLF or crew.

I'd rather fly 6'000 miles (and often do) than drive, sail, walk or run. I will live longer by flying so I will continue to do so.

[RoyHudd]

Recently flew an A330 at night through a massive and therefore unavoidable stormy area in the Med, painting green, no red/purple, climbing, lost airspeed indications, A/P disconnected, ditto A/THR, into Alternate Law, flying raw data. For about 16 minutes. No CB's, just icing and mod/severe turbulence. AOA discrepancy acc. QRH. Demanding.

Had this happened in a CB area, with wx radar u/s, things would have been even more awkward.

Had the AF crew experienced a reversion in bad weather, it is conceivable that the a/c could have been difficult to control. No difference in this situation between Airbus and B777.

All conjecture. But sadly much amateur guesswork posted here. I cannot comprehend why amateurs would wish to post their "ideas", any more than I would start posting my thoughts on neurosurgery on a dedicated website.

Many fools on this site. Pity the media pay it such attention. Perhaps that is why our PPL/SPL/aviation enthusiast pals feel the need to post. Devalues the discussion.

[efatnas]

Looks like they lost some navigation equipment, the radar among others. I personally don't like Airbus with all their fly by wire stuff... I think they might have been just overwhelmed by the failures and went into somewhat of a strong return which they couldn't see. Can't imagine handling a level 5 on standby instruments. That said, knowing the lousy WX enroute, without radar they should have made a precautionary landing in Recife or Fortaleza. A few hours into the flight, the copilots were probably flying and they might not have had the nerve to turn around without the captains permission. I was in this situation before; I'm just speculating, but me, without my radar working and other funny failures, considering the forecast......wouldn't have gone on. But then I'm a chicken. It is a big loss, and whatever happened, it seems like the crew was loaded up max.....well my five cents worth.....
Ciao

[vapilot2004]

Buoys might have limited value in this search.

The pingers can nominally be heard for about 2 miles (10,000 ft) The depth of the ocean in this area appears to be about 10,000 feet, but varies between about 8,000 feet and 12,000 feet. It would be pure luck to drop a monitoring buoy in a position where it heard a pinger, given the depth in the area, and the fact that at the surface, the radius of success is substantially smaller than 2 miles..

The distance the pinger can be heard will also be affected by any thermal layers in the ocean, and the terrain where the wreckage came to rest, both reducing the range..

The search won't begin to be effective until towed sensors that work below the surface are deployed. I suspect they are being flown in as we discuss this.

The type of sonobuoy that the P-3 carries is an improved version of the type that has allowed us to track Soviet boomers around the world using only the passive-type sonar, that is listening only.

Generally, these are laid out in a pattern-grid field for SAR use. An Orion can typically carry over 4 dozen of these things or more for that purpose. They don't just plop one in the water in a random fashion.

As Bubbers correctly pointed out earlier, for effective active sonar searches, a side-scan array is the best option as would be for finding a DFDR/CVR using passive hydrophones. The aforementioned sonobuoys are most often used for SAR operations for temporarily marking a location at sea.

As an aside:
At the frequency of the DFDR/CVR pinger (37.5khz) the average absorption rate in sea water is between 6-10 dB/km. This does not take into account thermal layers. The relationship between absorption and frequency is more on a log scale rather than linear. Lower frequencies can travel further than higher ones, not unlike the audio range in air.

[iptamenos]

Planning: did the crew evaluate the severe weather developing in the ITCZ? Were well informed?
Severe Weather Recognition: did they identify the problem of severe weather early? did they have the onboard equipment (WX radar, Comm for sigmets etc) functioning? The sat wx shows fast change in the wx situation the time of the accident.
Electrical Failures ACARS reports: did the onboard equipment gave the proper responce to the crew for the electrical failures? could the AF maintenance ground team help the situation? (HF and other links are available available)?
Decision Making: were well informed, not overloaded, to make the right descision and take proper action? did they have any option or there was no way out due to too late reaction after lost of all redundances of control?

We have to hear answers from the investigation board to questions of the circumstances how and why it happened and lessons learned.

[bigdunc]

ditto A/THR, into Alternate Law, flying raw data

Royhudd, why/how did you end up in alternate law exactly?

[Mercenary Pilot]

Details of F-GZCP ground collision in 2006.

DATE: 17.08.2006 LOCAL TIME: - LOCATION: Paris-CDG Intl AP (LFPG) COUNTRY: France
AIRLINE1: Air France TYPE: Airbus A321-211 REGISTRATION: F-GTAM C/N: 1859 AGE: 3 y + 9 m
AIRLINE2: Air France TYPE: Airbus A330-203 REGISTRATION: F-GZCP C/N: 660 AGE: 1 y + 5 m
OPERATION:1 ISP FLIGHT No.: - FROM: Paris-CDG TO: Rome-FCO VIA: -
OPERATION2: ISP FLIGHT No.: - FROM: Paris-CDG TO: Ouagadougou VIA: -
OCCUPANTS1: PAX: - CREW: x
FATALITIES: PAX: 0 CREW: 0 OTHER: 0
INJURIES: PAX: 0 CREW: 0 OTHER: 0
DAMAGE TO AIRCRAFT: minor
OCCUPANTS2: PAX: - CREW: x
FATALITIES: PAX: 0 CREW: 0 OTHER: 0
INJURIES: PAX: 0 CREW: 0 OTHER: 0
DAMAGE TO AIRCRAFT: minor

Both aircraft suffered damage in a ground collision at Charles de Gaulle Airport.
The tail of the A321 was substantially damaged when it was hit by the taxiing A330.

Damage to the latter was considered as minor.

[agusaleale]

Admiral Ackbar:

I know that Air France has been spewing too much stuff (lightning, pressurisation ,electrical failure, etc.) that they shouldn't in these early stages of the investigation but a retired Air France pilot (Jean Serrat) on France 2's main news broadcast last night stated that internally at Air France people are talking about extreme icing conditions in the time period preceding the crash...

As I said, I think AF should be a lot quieter than it is about this incident but thought people might like to know

Sounds very similar situation to the Austral accident in Fray Bentos, where the pitot probe iced and caused the crash, when the plane entered a CB.

[McGinty]

Here is the track referred to above, from the BBC web site. His weather radar must have been u/s.

http://news.bbc.co.uk/nol/shared/spl/hi/pop_ups/08/americas_enl_1244067525/img/1.jpg

[TripleBravo]

Red Paddy:
To me there is only one thing that could cause a shutdown that would leave non essential items operating while essential items such as the ADIRU's and ISIS shut down and that would be a fire in the avionics bay knocking out essential systems in an erratic manner and not shutting down non essientials first.

Paddy, my absolute sympathies to your neighbours, I understand that search for "the truth" is priority to them. There are multiple scenarios possible for that sequence of ACARS messages. I did not have the time to clearly verify how the mentioned systems are interconnected, but it is clear that PRIM1 and SEC1 are both at DC ESS as well as HOT BAT. So a massive failure at those could possibly lead to the picture we have and strike the aircraft at its very heart.

The computer systems are placed in a way in the e-bay that a local physical damage (bomb blast / fire) would not render e. g. all PRIM unservicable. This has been taken care for by design.

On the other hand, this alone does not render the plane uncontrollable. In essence, even only one backup ISIS could provide enough navigational aid to bring it back to earth in one piece (providing PFD or ND on its front), albeit I imagine the workload would be quite massive. If it were only the computers that were mentioned in the ACARS messages, it could possibly even still execute an automated ILS approach, if I'm not mistaken.

If the timing of the ACARS message correspond to the occurrence of failures over time is not sure at the moment. It could well be that the Maintenance Computer System, which collects these data, waits for several occurences of failure reports before relaying them to the home base. So for me it is not sure that really the AP disconnected at first, then the PRIM1 etc. It was not designed as a real-time DFDR backup, just for maintenance information and action, eliminating false alarms.

RWA:
In an Airbus, you can go to 'Direct Law' (I think!). But, also as far as I know, that means that you won't have elevators or ailerons to fly with, just the rudder and the trim controls.......
Direct Law delivers full authority. But other than Normal Law, the Sidestick commands real rudder movements without limits, as opposed to protected roll rates / g-loads etc. (Saw it afterwards, was already answered by khorton and GlidingAerobats.)

Quote:
As an add-on, if ADIRU and ISIS are completely non-functional, and you have no external horizon reference - is that even recoverable?
There is a gyroscopic horizon in the cockpit, if that's what you mean...
There is even 3 ADIRU (one would be enough), 2 ISIS (which can in a way replace the 3 ADIRUs), 3 PRIM (one would be enough), 2 SEC (which can provide backup to PRIMs) and so on... As said above, the ACARS messages alone do not indicate a helpless bird.


Lost in Saigon:
One very important piece of information is missing though. Was the cabin vertical speed indicating a climb or a descent?

I would very much argue this to be a climb, i. e. pressure loss. If it would be a descent, there had two independent computers to be failed *and* a source of overpressure to be present (aircraft descent, increased bleed air pressure), because the outflow valves would have to be stuck in their present position or being closed. But still to be verified, agreed.

Jo90:
Q. Which part of your aircraft is most likely to be struck?
A. The nose. No, lightning bolts do not come from upfront like birds.

J2P:
We only hear (but have no evidence or confirmation that it is "A330" wreckage) of "pieces" found and a 20km "oil slick".
As press has it, I think Brazil authorities confirmed that these were of AF447. But then, no information about where they derived this from...

icevane:
If one where to judge by that, they flew right through the worst CB activity in the region.
To me, Spiegel is not exactly known as a sound aeronautics treasure of wisdom, so I would not bet my money on their published charts.


If anyone could provide me with the MSN number of the cited Qantas A332 (AF447 being MSN660), then I could check the make and model of the ADIRU of these two.

[Zeffy]

************************************************************
NTSB ADVISORY
************************************************************
National Transportation Safety Board
Washington, DC 20594
June 3, 2009

************************************************************
NTSB TO ASSIST FRENCH WITH AIRBUS A-330 ACCIDENT
INVESTIGATION
************************************************************

The National Transportation Safety Board has accepted an
invitation from the French aviation accident investigation
authority, the Bureau d'Enquˆtes et d'Analyses (BEA), to
assist in the investigation of Air France flight 447, the A-
330 that crashed in the Atlantic Ocean off the Brazilian
coast on Monday morning.

NTSB Acting Chairman Mark V. Rosenker has designated senior
air safety investigator Bill English as the U.S. Accredited
Representative. The U.S. team will also include technical
advisors from the Federal Aviation Administration (FAA),
General Electric and Honeywell.

Information on the progress of the investigation will be
released by the BEA. The agency's phone number in France is
(33)1 49 92 72 00; their website is
http://www.bea.aero/index.php (https://mail.granitelp.com/OWA/redir.aspx?C=7cb51442d51b4886ba037586e06b7f5d&URL=http%3a%2f%2fwww.bea.aero%2findex.php), and their email address is
[email protected] ([email protected]).

###

NTSB Media Contact: Peter Knudson
(202) 314-6100
[email protected]
************************************************************
This message is delivered to you as a free service from the
National Transportation Safety Board.

[edmundronald]

SLF query:
Wouldn't it make sense to add a GPS position header to the ACARS messages? As ACARS seems to just be company-internal, non-navigating instrumentation, this ought to be possible without a lot of certification/red tape and might speed up the search for a missing or even ditched plane the next time around ...

Edmund

[protectthehornet]

the weather channel has just reported that two independent lightning observation newtworks say that the nearest lightning to the flight path was 150 miles away.

[Lost in Saigon]

Lost in Saigon:

I would very much argue this to be a climb, i. e. pressure loss. If it would be a descent, there had two independent computers to be failed *and* a source of overpressure to be present (aircraft descent, increased bleed air pressure), because the outflow valves would have to be stuck in their present position or being closed. But still to be verified, agreed.




I disagree with your assessment. Nothing would have had to fail as you describe.

Even if there was no failure of any system at all you would still get a "advisory regarding cabin vertical speed" once the aircraft descended in a dive below the pressure altitude of the cabin (6000-8000 feet)

You would have "caught the cabin" in descent resulting in a very high descent rate for the cabin.

The fact that the "advisory regarding cabin vertical speed" was the last message sent prior to impact tends to support my theory.

Does it not?

[ByteJockey]

The Associated Press: A summary of the final messages from Flight 447 (http://www.google.com/hostednews/ap/article/ALeqM5hma2MjmwBmMeHXoGEbr84hYuTXjAD98JFJR80)

French and Brazilian officials have described a "burst" of messages from Flight 447 just before it disappeared.

A more complete chronology was published Wednesday by Brazil's O Estado de S. Paulo newspaper, citing an unidentified Air France source, and confirmed to The Associated Press by an aviation industry source with knowledge of the investigation:

11:00 p.m. local time — The pilot sends a manual signal saying the jet was flying through CBs — towering cumulo-nimulus thunderheads.

11:10 p.m. — A cascade of automatic messages indicate trouble: The autopilot had disengaged, stabilizing controls were damaged, flight systems deteriorated.

11:13 p.m. — Messages report more problems: The system that monitors speed, altitude and direction failed. The main flight computer and wing spoilers failed.

11:14 p.m. — The final message indicates a loss of cabin pressure and complete system failure — catastrophic events in a plane that was likely already plunging toward the ocean.

[torquebox]

Jo90:

Quote:
Q. Which part of your aircraft is most likely to be struck?
A. The nose.
No, lightning bolts do not come from upfront like birds.



Actually from experience lightning pretty much always hits at the front of the aircraft. Normally strikes in a pattern along the airframe but definately starts at the front. Radomes seem to cop a lot which is why they have such massive lightning diverter strips.

[Lost in Saigon]

A more complete chronology was published Wednesday by Brazil's O Estado de S. Paulo newspaper, citing an unidentified Air France source, and confirmed to The Associated Press by an aviation industry source with knowledge of the investigation:

_ 11 p.m. local time — The pilot sends a manual signal saying the jet was flying through CBs — towering cumulo-nimulus thunderheads.

_ 11:10 p.m. — A cascade of automatic messages indicate trouble: The autopilot had disengaged, stabilizing controls were damaged, flight systems deteriorated.

_ 11:13 p.m. — Messages report more problems: The system that monitors speed, altitude and direction failed. The main flight computer and wing spoilers failed.

_ 11:14 p.m. — The final message indicates a loss of cabin pressure and complete system failure — catastrophic events in a plane that was likely already plunging toward the ocean.



The final message was "advisory regarding cabin vertical speed". Everyone seems to be making false assumptions of what this means.

The problem is that this and all other "reports" are not reporting facts. They are simply interpretations of the various news media trying to put it into layman's terms.

[wilyflier]

Small point you say lightning strike doesnt come on the nose.Sorry, ive had one like that, build up of static ,then a discharge explosion straight forward off the nose , broke the radome and disabled weather radar.

[PJ2]

Lost in Saigon;
The fact that the "advisory regarding cabin vertical speed" was the last message sent prior to impact tends to support my theory.
[removed comment]

I know that there are a number of reports "out there" concerning such messages but they are not "fact" until they are in-hand and available. If you have an actual source, perhaps it could be provided? As I posted earlier, any ACARS message will have a time stamp, a reference to the ATA System Chapter and a text message describing the failure(s).

I'm not disputing that they exist but am disputing, until we see these messages, their timing and content. I simply don't trust the media, Air France's press information or anyone else's information. There are too many guessers, speculators and interested parties to trust anything but original sources.

On a related matter upon which I earlier posted, hopefully too, the copies of the last logbook page were pulled before departure as is standard procedure, so we can learn what, if any, snags the aircraft had and either cleared or MEL'd before departure.

We have absolutely no other evidence upon which to base speculation so everything is possible and therefore nothing is privileged as probable.

The actual aircraft course and position has still yet to be determined. The Vazquez presentation itself states that the line shown is "extrapolation".

PJ2

Lost in Saigon - post edited to respond to your last message:
They are simply interpretations of the various news media trying to put it into layman's terms.
Precisely, and very poor layman's terms at that. The imprecision is entirely misleading and distracting and is of no use whatsoever.

[Lost in Saigon]

Lost in Saigon;

When you say "the fact that..." in reference to the ACARS messages, to what documents do you refer as "fact"?

I know that there are a number of reports "out there" concerning such messages but they are not "fact" until they are in-hand and available. If you have an actual source, perhaps it could be provided? As I posted earlier, any ACARS message will have a time stamp, a reference to the ATA System Chapter and a text message describing the failure(s).

I'm not disputing that they exist but am disputing, until we see these messages, their timing and content. I simply don't trust the media, Air France's press information or anyone else's information. There are too many guessers, speculators and interested parties to trust anything but original sources.



I agree. No one has shown us the actual ACARS reports yet. The initial reports simply said "advisory regarding cabin vertical speed". It appears to me that many(but not all) subsequent reports added "loss of pressurization" on their own.

[PJ2]

Lost -Sorry, we're overlapping one another here. It appears to me that many(but not all) subsequent reports added "loss of pressurization" on their own.

Yes, I think so.

I suspect when the ACARS messages are finally released in some form, there will be dozens of them trying to keep up with a degrading situation and therefore all within a very short period of time. The FWC's (flight warning computers for others) would be generating these until the power was no longer available. Such a point may or may not be a structural failure point - we just can't determine that yet.

[md-100]

does the ACARS transmit in VHF or HF?

[captplaystation]

Am I the only one that thinks WTF? ? the PIC or indeed anyone in the flightdeck is doing bothering to send a "manually entered" message to some ops bod sat in an office several thousand km away in CDG saying they are having a rough ride ? with the greatest of respect so F? W ? Did they expect them to call Sarko and ask if he could ask Obama to have the clouds eliminated ? this strikes me as either so much BS. . . OR I am seriously worried that any crew of an A 330 could waste valuable time "texting" OPS instead of concentrating on where they were pointing the airframe. . .Pleeeaase tell me this isn't true.
Jeezuz, what next, beam me down Scotty it's rough up here. . . . Nah ? you are joking , right ?

[blueloo]

I agree with captplaystation: never once going through turbulence have I thought of ACARSing ops to let them know its bumpy. Why would you? It doesnt achieve anything. ... Seems very bizarre.

re Huck reply below: Yes I agree - but it is a different story advising Air Traffic control for Weather deviation purposes, compared to the company. As for other company traffic on that route - maybe - but I would be surprised if they operate that route that frequently to make it worthwhile.

[PJ2]

md-100;
The ACARS transmits on VHF frequencies when in range of VHF reception and automatically switches over to SATCOM when required.

The SATCOM antenna is on the top of the fuselage and can transmit to satellites in all but very high roll angles.

The ACARS is powered by the AC1 bus. The #3 VHF is powered by the DC1 bus.

Only #1 VHF is powered by the DC Essential bus. There are no communications equipment powered by the Hot Battery Bus.

[Huck]

never once going through turbulence have I thought of ACARSing ops to let them know its bumpy. Why would you? It doesnt achieve anything. ... Seems very bizarre.

1. Maybe he was advising ATC via datalink that he was deviating.

2. Maybe he wanted to warn other company aircraft.

[wes_wall]

I agree completely - thats why I asked the question. It sounded strange to me, and it still does. More over, this information surfaced very late in the thread, leading to suspicion that it is even factual.

[Phalanger]

There is no information of a message being sent out of a radar or any WX related failure. I'm sure that by now AF would have said so if they had it, cause then it would only help their cause. So for now I am disregarding anything to do with that idea.

It's interesting that spoilers are reported as failing in the last set of messages. This would suggest they were still intact till this time (and other things were not falling off). Personally the biggest hint lies with the Qantas/Unknown Airline events. These reports stated while the incorrect readings started the chain, the computers analysing them failed as well. While there maybe be three different types of computers, but they are all progamed to operate the same algurithims. So if there is a problem in thier reasoning, all three computers will act on it (which is was the Qantas incidents have showen). Turbulents can induce strange reading, and if these computers algurithims has some error in them or do not account for cirtain inputs, then it will create uninticapated outputs (like the systems turning off).

[Will Fraser]

I noticed very early the "report" concerning the ride, was that the pilot reported "hard turbulence". He obviously thought it important to get it on the CVR and apprise company of his situation. I know the "hard" was the word used, as I thought it may have been a mistake in translation.

[bond7]

Whatever happened...it's obvious to all now that the crew didn't have enough time to address the problem in hand on time. So please, to the Mr. know it all :ouch:...please reserve your smart comments to yourself or at least help shed some light to the crash investigation agency as to what might've happened...or at least help in locating the ELT!!...
And with ACARS?!?...I wonder how long before a better system is implemented?

[ED13]

Given all (little) evidence avaliable i'm not discounting anything, but given the flight path and the weather info, the fact that af447 flew into a storm cell which as i understand it was at or approaching peak intensity it seems logical that the weather is the primary candidate for the cause/contributing cause/s of the crash.

Must say however that the public relations annoucements of AF re: early call of lightening as cause and the 'the black boxes may never be found' does not sit well with me........:mad:

[Phalanger]

Must say however that the public relations annoucements of AF re: early call of lightening as cause and the 'the black boxes may never be found' does not sit well with me........http://static.pprune.org/images/smilies/censored.gif
It does not sit well with me, along with the fact they kept information about the messages close to them and away from Brazil for a long time after the aircraft went missing. I think there is something in these messages that is important and they may just be delaying their release. These message are details, and in 4 minutes there is enough time for them to create a picture of what is happening,

[KRviator]

If anyone could provide me with the MSN number of the cited Qantas A332 (AF447 being MSN660), then I could check the make and model of the ADIRU of these two.The aircraft involved in the QF72 incident is VH-QPA, MSN 0553, according to the preliminary accident report (http://www.atsb.gov.au/publications/investigation_reports/2008/AAIR/pdf/AO2008070_interim.pdf).

Also from the ATSB report, the ADIRU's fitted to the aircraft at the time were as follows:
Model name: LTN-101 Global Navigation Air Data Inertial Reference Unit (GNADIRU).
Part Number: 465020-0303-0316.
ADIRU 1 Serial Number 4167
ADIRU 2 Serial Number 4687
ADIRU 3 Serial Number 4663.

[etesting2000]

I imagine they are responding to some political as well as industry pressure but also trying to get all of their ducks in a row for the investigation. Every scrap of Mx, crew training, ops manual, everything. I do not understand a partial non transcript release unless some one said "just give me something to keep them off our backs for a bit". I would find it hard to believe that the data they had did not tell them the bird was down.

I saw a note above about two sources of lightning data. I'll dig into the NASA site tonight to see what data they have.

[AMF]

blueloo I agree with captplaystation: never once going through turbulence have I thought of ACARSing ops to let them know its bumpy. Why would you? It doesnt achieve anything. ... Seems very bizarre.

It doesn't seem bizarre to me at all. Giving met PIREPs of severe weather conditions that could affect other aircraft (turbulence, ice, etc.) should not only be considered a professional obligation, but mandatory in some during some ops, including crossings.

This ACARS message from the AF pilot that reported they were experiencing "hard" turbulence came 10 minutes prior to the auto-ACARS mx messages was one of the first things brought to light on this thread which quickly drifted off into lightning-and-techie talk with great abandon. This info isn't "new", and it's easy to imagine where a bad situation got worse with regards to turbulence and convective activity if their hands got full.

If the aircraft had slowed to Max Turb Air Penetration speed, someone else pointed out that at 35,000 with it's probable loading at that point for an 11 hour flight there existed approximately 15kts between Max Turb speed and clean low-speed cue, and only 25 kts between Max Turb and Low Speed buffet. NOT a good place to be in with anything more than moderate turbulence.

I assume the pilot (if he thought the turbulence severe enough to report it) would also have slowed to Max Turb Air Penetration Speed so things on the aircraft didn't begin to break, which puts it closer to the low speed buffet boundary and at FL350 with heavy weight, unfortunately it becomes more difficult to accelerate out of a gust/shear/convection-induced deteriorating low-speed condition due to relative-reduced engined performace.

Trying to maintain q-corner limits at high altitude while experiencing severe turbulence and updrafts/downdrafts of varying amplitudes can be an impossible situation for the A/P, or the pilot when the A/P disengages due to an exceedence of one of it's pitch/roll/etc parameters. What I gather from the Airbus drivers here, an out-of-parameters A/P disengagment such as would happen if the aircraft were being pitched or rolled past A/P limits will revert the flight controls to Alternate Law, which means hand-flying with no FBW stall protection or limtiting to half/low bank even at FL350. Please correct me if I'm wrong.

The greatest danger of high altitude flying ANY (Airbus, Boeing, whatever) aircraft through severe turbulence isn't that the aircraft will break up and lose control, it's that it will lose aerodynamic control and perhaps be impossible to recover from if it begins breaking on the way down or can't exit the severe conditions. Then the issue of engine-flame out looms large. In jet-upset incidents, engine flameout can come early and without engines electrics and pressurization are also suddenly added to the largest problem of re-gaining and maintaining aerodynamic control.

The fact that there were reports that little or no lightning was detected in the cells the flight track was shown going through or near points to the worse possibility it may have entered an area of developing cells which are where the most severe updraft and airmass convection is taking place, and least detectable moisture for the radar to paint. Aircraft have deviated themselves into a corner this way when snaking their way between cells and into "soft spots" and finding a developing cell instead of avoiding the entire area because it's too dynamic and unpredictable, or not visible due to it's imbedded nature or at night.

Mature and dissipating cells emit the most lightning, and attempting to (or inadvertantly) flying above a developing cell is a non-option, since the updraft turbulence rises to a mile or more above it's visible top.

[Captain-Crunch]

Good point "Lost in Saigon". "Catching the cabin" in say, a jet upset would indeed cause an unpleasant cabin vertical change down low. (Don't ask how I know.) (catching the cabin that is, not an upset!)

I was an early generation bus cpt (A300/310 some of the first of the long series of electric jets by bus.) The radars in the 90's we had were useless for a time in auto. A declutter mode of some type would see a huge red cell and erase all but the worst part. Several of us penetrated huge cells, so everybody started flying in manual until, a year later, a new "load" showed up, and the problem mysteriously disappeared. I object to the secrecy and stealth of aerospace companies, "finishing" the design in the field by slipping new software loads into the fleet without line pilot and union input. Just denoting a revision is not enough information in my opinion.

It was quite common for us to dispatch with an inop generator or APU. The big concern was that our APU's really weren't that great, so the specter of possibly tripping the yaw damper off was real in some scenarios.

This means that if the yaw damper cannot be regained, that, to avoid losing control in wicked dutch rolls, you had to descend and slow down pronto, or else go into combat with the roll spoilers to keep it right side up (not really a line pilot skill?) Not a nice thought threading a squall line at night after you've just been blinded by a huge flash. Could really put you in peril.

To A330 drivers: I know it's unlikely, but If both gens pop off the line due to a strike, do you have something analogous to our aux green system gen? (off of hydro) Will it cover buses for yaw damper and radar?

Thanks

Crunch

[blueloo]

It doesn't seem bizarre to me at all. Giving met PIREPs of severe weather conditions that could affect other aircraft (turbulence, ice, etc.) should not only be considered a professional obligation, but mandatory in some during some ops, including crossings

Absolutely - but I would tell Air Traffic Control this. Not operations/my company. My company is (i wouldnt say not going to but very improbable) unlikely to ring up British Airways, KLM, Air France United, etc etc etc to advise them individually of turbulence enroute.



As an aside, my post and capt playstations post are referring to the rumour that Air France Ops were ACARS' a report on turbulence - NOT Air Traffic Control. So far nobody appears to have verified where the msg was addressed to. Telling someone at my company is the last thing on my mind whilst flying an aeroplane through presumably moderate to severe turbulence. Trying to type it wouldnt be much fun either.

[Space Monkey]

The speculation on ACARS seems founded on far too unreliable information.
L'Express and Le Figaro (see Les navires brésiliens s'approchent de la zone du vol AF 447 (http://www.lexpress.fr/actualites/2/de-nouveaux-debris-de-l-avion-disparu-apercus-dans-l-atlantique_764843.html) for example) are citing some anonymous source denying that there was any loss of pressurisation message. In other words, concerning these messages, given that different sources are giving opposite statements, we simply know nothing at all. I know that it is a rumor forum, but when the information available lets you with a 50% chance for one thing and 50% for the opposite, there's not much rumor you can build from that (sources citing a depressurization and sources citing no such messages seem equally reliable a priori (maybe all equally absolutely not reliable) given that they come from major newspapers)

I don't see why Air France should publicly release the detailled sequence of ACARS messages, it seems inappropriate to throw this information out now which belongs to a preliminary report from the BEA later (and given how Air France screwed it up by initially speculating about lightnings, it's no wonder that they are a little bit more careful now). I do not see why this should be interpreted as "hiding" something, it seems professional and responsible, doesn't it?

[NSEU]

Lots of reports about the Radar possibly being unserviceable. I don't know about the Airbus, but on our Boeing aircraft, if the radar is unserviceable, it tells you so (in the form of various messages on your displays .. e.g. Antenna Fail, Weak, etc)... and ACARS registers this, sending a message via VHF or SATCOM to our maintenance centre.

If the Airbus is the same, and the radar failed, I'm sure it would already be public knowledge.

[AMF]

blueloo Quote:
Absolutely - but I would tell Air Traffic Control this. Not operations/my company. My company is (i wouldnt say not going to but very improbable) unlikely to ring up British Airways, KLM, Air France United, etc etc etc to advise them individually of turbulence enroute.

I have no doubt that the crew would be intending to advise ATC since their next reporting point wasn't that far away, and perhaps they found themselves too busy dealing with increasingly averse conditions in an extremely dynamic weather situation. Perhaps AF SOPs require they notify the Company of adverse conditions, especially if there can be sick passengers, damaged food carts if they aren't secure, or whatever.

Whatever the reason, I find the notion that AF is making up fantasy messages ludicrous, and there's nothing "bizarre" about it. In fact, if it helps shed more light for investigators, it was a very pertinant and timely message that may dissapoint the spark-chasers playing Electrical Sherlock Holmes here and conspiracy theororists, but may point the most direct way to the non-complicated truth.

In a case where a reliably-designed aircraft quickly quit flying, perhaps more people should be spend some time becoming versed in high-altitude aerodynamics of jet aircraft and upper level atmospheric conditions where they fly, and less time following and dissecting electrical schematics. If you don't fly up there, for a first lesson go stand and balance on a basketball and you'll get an idea of what an airplane does on a good day, let alone when things get rough. Of the consiracy theories......no comment.

[vapilot2004]

Those who are questioning the AF crew's ACARS message to flight ops:

HF communication is often degraded within hundreds of miles of an active storm cell let alone being right on top of one. Over the ocean there is no VHF communication, which has the advantage of being less prone to the electrical arc noise that lightning produces. An ACARS communique would be the best way to pass along this information.

[DanAir1-11]

>> Barbies Boyfriend "Is there anyone on here with intimate knowledge of the A330 structure that could refute this? Is it a particularly 'strong' a/c, like the Bae 146 for example? I suspect not."

Being 'particularly strong' is not comprehensive insurance against structural damage / in-flight break-up in an encounter with exceptionally severe turbulence, or, if mis handled within severe turbulence.

There are two examples of "strong" aeroplanes breking up that spring to mind, both occurring in 1966.

03/05/66 - BOAC Boeing 707-436 broke-up in flight and crashed near Mt Fuji, after a violent encounter with turbulence (mountain lee waves) that imparted structural loading significantly in excess of the design max.

06/08/66 - Braniff BAC 1-11 203AE broke-up in flight and crashed after traversing a strong squall line shortly after departing Kansas city. Subsequent investigation into the accident determined that the a/c would have to have encountered a gust in excess of 140ft/sec. at an upward angle to cause the catastrophic failure of the tailplane that was determined to be the trigger to the break up.

I am sure that you will agree that both the 707 and 1-11 are 'strong' aeroplanes, and having personally accumulated a significant amount of hours on the 1-11 I can attest to it being an exceptionally robust piece of equipment, however, I was fortunate never to have experienced the absolute upper limits of that robustness.

[blueloo]

AMF: I have no doubt that the crew would be intending to advise ATC since their next reporting point wasn't that far away, and perhaps they found themselves too busy dealing with increasingly averse conditions in an extremely dynamic weather situation. Perhaps AF SOPs require they notify the Company of adverse conditions, especially if there can be sick passengers, damaged food carts if they aren't secure, or whatever.

Think I'd rather get to a smooth weather free spot, have the aircraft under control, before advising ops I have a broken cart or sick passengers, or flying through hard turbulence.

Something about aviate, navigate communicate rings a bell.

Who knows maybe they did get to a relatively clear area - but this is all going off on a tangent - nobody knows where the msgs where sent, and what the wx situation was when they were sent.

[division1]

The final message was "advisory regarding cabin vertical speed". Everyone seems to be making false assumptions of what this means.

Funny my maintenance notes and vacbi make no reference to any such ecam msg.
Cabin vertical speed indications can pulse when the rate is >1800 ft/min or <-1800 ft/min.
An advisory regarding cabin pressure would make more sense.

[NSEU]

HF communication is often degraded within hundreds of miles of an active storm cell let alone being right on top of one.

Do Satcom voice communications suffer similar degradation in these conditions? If there was any sense of urgency, I'm sure I wouldn't be tapping at a keyboard for several minutes :bored:

[vapilot2004]

Do Satcom voice communications suffer similar degradation in these conditions? If there was any sense of urgency, I'm sure I wouldn't be tapping at a keyboard for several minutes


@NSEU:

No not from lightning, but SATCOM is known to unreliable when the aircraft is pitching about from any turbulence encountered. Did this aircraft have SATCOM voice capabilities? My first thought would be no as it is not common.

Typing an 80 character message on the FMS for ACARS transmission takes me and crew about 30-40 seconds.

[hellsbrink]

Ahh yes, our infallible satellite tracking/transmission/receiving systems.

You do realise how often up/downlinks to/from satellites drop out because of things like storms, don't you. Let's just say they are not as reliable as you would love to think, especially as to get a signal from A-B can mean a few "jumps" from satellite to ground station and back before it reaches it's destination. A good storm in the vicinity of any of these up/downlink stations means no signal, as I'm sure we have all seen with TV signals.

Just because a GPS works in an aircraft when the weather is good does not mean it is possible for the system to be 100% reliable, and that is something anyone who has used such a thing or has any knowledge of sat systems knows.

[Wiley]

I wonder if this tragedy might convince at least some of the many pilots who fly around in the cruise, sometimes at night or in IMC, in 'TERRAIN' mode that it's really not a good idea? (...and those trainers who teach this practice?)

Mods, I appreciate that you have had a gigantic task deleting posts on this thread that don't pertain to this subject, (as you did my earlier post on this subject), and I appreciate that over the sea, the AF crew would definitely not have been using this mode.

However, more than one person has suggested the possibility that the AF aircraft entered an area of severe turbulence where for whatever reason, the radar returns did not show them how serious the weather immediately ahead of them was.

Pilots who fly along in TERRAIN mode, relying on the other pilot's display for weather radar returns, in my opinion at least, are throwing away an important 'last slice of cheese' in Dr James Reason's model.

Every one of the professional pilots posting on this thread is doing so hoping we can come up with some plan to ensure something like this tragedy can be prevented in the future. My comment about the (I think ill-advised) prolonged use of TERRAIN mode is made with that in mind.

[protectthehornet]

has a nifty little feature

position

wx...including ice, turb, other...just highlight and enter...

and takes about 10 seconds or less to send a pirep...and if one guy is flying witht the plane on autopilot it doesn't take long for the other guy to send a message...perhaps hoping that OPS would send back some knowledge like: company reports ride 50 miles west good

[DanAir1-11]

Having been out of 'the game' for quite a while, and having only ever operated 'older' types, I am not au-fait with the types of wx radar currently in use. An issue that we used to endure with the old 3cm band and to a lesser degree the 5cm band was that if attenuation due to precip was sufficiently great, it generated a contour hole or suckers gap on the display by effectively supressing the return from any convective cells immediately behind the area of high precip and thus potentially lulling the uninitiated into a false sense of security.

Has modern equipment eliminated or reduced this phenomena?

I ask only simply because with avoidance being the name of the game, there would surely be some mitigating factor why (IF in fact they did) the crew attempted to traverse a CB? The obvious reason could be that they simply couldn't see it? There will be a myriad reasons as to how one could lose wx radar, and I am not at all qualified to speculate re the electrical side of what could possibly go awry, but would appreciate a head's up from those significantly more informed than myself.

[Gary Brown]

SpaceMonkey wrote:

The speculation on ACARS seems founded on far too unreliable information.
L'Express and Le Figaro (see Les navires brésiliens s'approchent de la zone du vol AF 447 (http://www.lexpress.fr/actualites/2/de-nouveaux-debris-de-l-avion-disparu-apercus-dans-l-atlantique_764843.html) for example) are citing some anonymous source denying that there was any loss of pressurisation message.

That's not quite what the Figaro report says:

Paul-Louis Arslanian, invité du journal télévisé de France 2 ... a aussi affirmé qu'à "(sa) connaissance", aucun message automatique n'indiquait de dépressurisation, contrairement à ce qu'affirmait Le Point mardi.


"-Paul-Louis Arslanian, interviewed on the TV France2 news program ... also stated that to his knowledge, there was no automatic message regarding depressurization, contrary to what was reported in La Point on Tuesday."

Arslanian is the head of BEA, the French air accidents investigation bureau.

AGB

[LaOnda]

Air Traffic "Control" in that area? HF! 20mins spacing with same M-number! Anachronism! That's why all smart pilots northbound ask for max FL within Recife (Radar), because they won't get FL-changes from Sal or Dakar within the next 3 hours or so. As AMF correctly posted: Here you are, heavy at maxFL, in the coffin corner, close to low and high speed limits. If you get positive windshears/updrafts, Auto Thrust/Auto Throttle will reduce power. In a strong positive shear that might not be enough. The airplane enters into overspeed. At about 6 knots (?) in the overspeed regime, the Auto Pilot disengages and overspeed protection mode let's the airplane climb to avoid a further possible destructive speed increase. Normally, when airspeed reduces below "barber pole", the auto pilot should be engaged again (FL-CH/Open-Descent), and will smoothly descent again. Airbus pilots should know this ( is this trained by AI and AF?).
If you decide to fly manually- still slightly in overspeed- sidestick inputs (e.g. down) are restricted, until you come out of the overspeed range. Manual flight at that altitude, may it be with a Boeing or Airbus, is never an easy task and not really recommended.
If the pilots decide to give a sidestick-down-input still in overspeed, to descent back or to reduce pitch, the manual inputs are dampened, until the aircraft comes out of overspeed. Coming out of overspeed, the (now not any further restricted) input might be too large, resulting in possible minus-g , and possibly many hurt passengers, as has happened before in incidents. Structural damage might be possible, depending on g-force.
Let's hope they find the Red Box(es).
Be safe.

[Space Monkey]

AGBagb, indeed I was going to post this, since I missed at first that the source was actually the head of the BEA.
He declared that "to his knowledge" there was no ACARS message about depressurization, but I would trust his knowledge, since he is at the head of the bureau responsible of the investigation, more than Le Point, which is a newspaper.
The point is: different ACARS messages are discussed here, but it seems to me that the only fact really confirmed by the BEA is that there were some ACARS messages. All the rest seems to come from newspapers. Do we really know that there was an ACARS about the autopilot being disconnected, what are the sources for that, beyond some journalist referring to unnamed sources?

Paul-Louis Arslanian also declared that the preliminary report shouldn't be expected before the end of June, and before that I would guess that the content of ACARS message will remaing pure speculation. Paul-Louis Arslanian also said that the current phase of investigation was consisting in sorting out the ACARS messages and working on their chronology - you wouldn't expect an investigation bureau to release details about some data they're still working on.

I also note that it was often reported that he said that "the flight recorders might be never retrieved" and many people use this citation as a way to feed conspiracy theories, but this was taken out of context. He said that there was no way to know for sure whether the flight recorders would ever be recovered, because no attempt has ever been made to find flight recorders at the potential depths found in this area. Quite a different statement.

[pattern_is_full]

Several people have asked why a malicious act has not been mentioned - much - as a possible cause.

First, because the only hint of it was a single bomb threat - against a different flight - in a different city - two countries and 1000nm away - 3 days earlier.

Second, because there was a clear and obvious threat to the flight from the tropical storm line across the planned, reported and airway-defined flight route - and close to the wreckage site.

If someone walks into busy traffic and falls down dead, the general response will be to try and figure out which vehicle hit him - not look for a possible sniper on a surrounding building. What are the odds?

Third, because there is not much that pilots can do, outside of barring the cockpit door, against terrorism or a bomb that got through security. A pilots' forum is naturally going to focus on the things within their speciality and experience that could go wrong and could be fixed in future. Procedures, skills, planning, equipment, and aircraft design.

@PJ2: I'm not sure why you are so doubtful about the route of flight as plotted against the weather charts. It was the route planned, it followed an airway, it was confirmed en route by the aircraft reporting INTOL and expecting TASIL in 50 minutes, on that airway, and the wreckage is fairly consistent with an extension of the line INTOL/TASIL, allowing for wind and other drift. It is possible that the aircraft diverted, or even turned around. But there is no evidence of it, and the other evidence is in favor of the plane following the route as planned. Best evidence rules.

On the subject of lightning, yes, The Weather Channel did check 2 lightning plotting networks which both recorded no strikes near the AF447 presumed flight path. At the same time the meteorologist also said that lighting bolts can follow CB anvils up to eighty miles horizontally (in his experience) - and that the networks occasionally miss strikes. So it is absence of evidence, not evidence of absence. Not persuasive either way.

[etesting2000]

Data from the Tropical Rainfall Measuring Mission (TRMM) spacecraft Lightning Imaging Sensor. I have not caught the Wx channel sources in the last half hour so don't know who they are quoting. Correction, caught it, source World Wide Lightning Detection Network. The data below shows none near the area. I looked at prior and post date also, same. But here could be gaps.

Lightning and Atmospheric Elelectricity Research at GHCC (http://thunder.msfc.nasa.gov/data/index.html#TRMM_DATA) Data source

Lightning and Atmospheric Elelectricity Research at GHCC (http://thunder.msfc.nasa.gov/data/query/2009/2009.149.html) Data

[bugg smasher]

Has modern equipment eliminated or reduced this phenomena?

A very reasonable post, Dan.

I fly with the latest radar units, dual installations, pulse Doppler capability, lightning detection, vertical slicing of the target, and so forth. With a cell of sufficient size and water content, however, such as those present in a well-developed line along the ITCZ, attenuation is inevitable, at least as far as I know. The tell-tale radar shadow behind the scan is a place most of us fear to tread.

In our experience, a thorough weather brief from a competent dispatcher, an appropriately cautious flight plan routing, even at the cost of precious extra fuel, plus the very recent addition of an in-cockpit internet connection that provides us near real-time satellite and radar composite snaps of severe weather areas, has proven most effective where avoidance becomes key.

That is not to say Air France does not have this already in place. One can only speculate at this point.

[llagonne66]

This equipment is selectable SFE on A330.
QFA : Northrop/Litton
AFR : Honeywell

[727gm]

Why would the Captain do this? A question to those still flying.

Some companies require a position report sent manually to Ops, every so often(e.g. every 3-4 hours), in addition to ATC positon reporting. Fixed format, with spaces for wind/temps, and toggle-able WX condition:

SKY: CLEAR/SCATTERED/BROKEN/OVERCAST/UNDERCAST/IMC

TURBULENCE: SMOOTH/LIGHT/MODERATE/SEVERE

If this was their practice, then it wouldn't be execptional, just routine....

[silverelise]

There is an AF pilot in one of the papers today claiming it "has to have been" a bomb, because "I have been flying these aircraft for 10 years and a lightening strike would not bring one down". He also mentions the bomb threat received a few days before which caused a 2 hour delay whilst the aircraft was searched, although he acknowledges that this was on a different route. The pilot wished to remain anonymous - I wonder if that is because of the airline's previous MO for dealing with pilots who speak against the party line following an incident, or if the paper is just making the whole thing up.

Either way, as has been mentioned elsewhere on this thread, the airline were unusually quick to come out with a likely cause IMO.

[PJ2]

pattern_is_full;
Best evidence rules.
I'm not convinced there is any such thing as "best" evidence, yet - that's my main point. I concur with all your points but that doesn't yield an accurate position - it only surmises.

The point regarding the routing is minor but the claim of the Vazquez preso for example, is that the route depicted IS the route taken and it's not necessarily so. He himself cautions that all positions after INTOL are "extrapolations". Videos and animations are very powerful tools these days but can be quite incorrect depending on a number of factors. The Vazquez animation is very good as is his analysis and may turn out to be highly useful if not accurate but we should not permit ourselves to assume that such is the case at present, at least not without supporting data. We do not know where whatever-happened-to-the-aircraft, happened. The unreliability increases with time after the last position report of course, but you knew that... ;-)

In the end we may not have the luxury of much data and will have to draw conclusions based solely upon what we are seeing today. I truly hope that that does not turn out to be the case.

Normally (over land or closer to land), we would have a wealth of other information such as radar/transponder plots and ADS positions (in areas so equipped). We would have ATC records and we have always had an accident site. The evidence (this, the ACARS and anything else), is so thin that it is important to verify all of what is available as strongly as possible.

That's all...I realize and understand the kind of informal rule-making regarding evidence that's going on at present. In the end it may be all or partially correct but at the moment no one can say. At the same time many here and elsewhere are drawing conclusions anyway. Go figure.

With such little evidence, the extreme desire to determine what happened by a number of "interested" parties carries, I think, a certain risk, the first of which among many, is hind-sight bias.

[Phalanger]

This equipment is selectable SFE on A330.
QFA : Northrop/Litton
AFR : Honeywell
The Qantas incident reports says that faults also run in systems above this.

[straightfeed]

I'm wondering if the preflight planning or any discussions the crew had preflight might reveal the start of the chain that caused them to accept the flight plan.They must have studied the ITCZ wx and based their plans on that.

1. Would a flight plan rerouting direct to say west Africa then north be unavailable to 2 engine ops due to the long overwater leg ? Maybe not.

2. This leaves an alternate route to the north west of South America, with an enroute fuel stop which may have flightime limitations or even be impossible to reroute around the ITCZ considering its forecast size.

3. Have a go using radar to find a hole in the ITCZ. Maybe closer inspection will see if AF447 made any deviations. Nearest airways are along way away (UN866 and UB623). Crews turn off airways for a few miles without contacting ATC in a non radar environment. Especially allowing for the hassle of using HF radio when flying the aircraft is priority No.1.

4. If no luck in getting through then the possibility of dropping into Recife ( an AirFrance station in my days) for a replan.

SFD

[NotAnExpert]

I'm not familiar with the FBW systems on any of the Airbus models, but hopefully someone can help me with this question. If the pilots were to manually shut down the flight computers (suspecting they were going haywire and compromising the safety of the a/c or to try to put the aircraft into Direct Law to contol it themselves), would ACARS send error messages stating that the computers had failed?

[PJ2]

NotAnExpert;
would ACARS send error messages stating that the computers had failed?
No, the message sent would be that the computers had been turned OFF. ACARS reports of failure modes are almost always accompanied with text messages of the fault(s).

That said, there are no procedures in place for the crew to turn the flight computers, (PRIMs, SECs) off to "gain control of the airplane" - it doesn't work that way on any 320/330/340 type. The QF experience may or may not modify that.

[NotAnExpert]

Thanks for your insight. I'm just trying to figure out how the computers could have failed in rapid succession, provided the unofficial reports of the ACARS messages are correct.

[RAD_ALT_ALIVE]

Those who talk/ask about re-routing at the flight-planning stage aren't fully aware of the operational realities of a longhaul operation.

If pilots were to ask dispatchers to route them around all the forecast areas of ISOL/OCNL CB activity that is in every SIGWX chart, there'd be absolute bedlam in every dispatch office. Some airlines even persist in choosing a route that takes you straight through an enroute cyclone/hurricane/typhoon.

It falls to the flight crew to assess the weather and order enough fuel to allow them to divert around individual/clumps of TS cells as they encounter them enroute; if your planned route takes you through an area of forecast ISOLated Cumulo nimBus, then you'd expect to uplift enough extra to go around one or two cells - not hugely inconvenient. But, however, if your flightplanned track looks like it will go through an area of OCcasioNaL CB, then it's time to think of taking a decent extra amount, in case the forecast is accurate and you wind up quite a way off track.

Some system failure or multiple failures of an extremely complex nature has befallen the crew on this occasion; I personally would very much doubt whether lightning had any contribution to play. My money is on probe icing or a dud ADIRU. The QF crew were fortunate enough to have been in day VMC for most of the event - which made their excellent handling of the failure that much easier. Night IMC would make it an entirely different proposition.

[Captain-Crunch]

I've seen tops above 60,000 ft at the equator. :uhoh: Accidental penetration of shorter columns can be violent. On the A310, you can loose both tat probes and loose Sat for a time with ice. This happened to us once going through a benign looking arm of weather a hundred miles from a typhoon near Borneo. The yaw dampers popped off followed by the autopilot. The Airbus autothrottles went bezerk so had to disconnect those. All airspeed was lost. It got very noisy from HAL screaming about wind shear and other incorrect imagined problems. All three Altimeters disagreed so we didn't know which was right. A few minutes later in clear wx everything came back. Like nothing happened!

My theory: I never had this happen in any boeing or douglas aircraft. I beleive airbus probe heating is occasionally weak (again, just compared to boeing.) I feel airbus automation actually increases pilot workload (AW&ST) Aug 1995, which is of course, exactly the opposite of how this equipment was originally marketed.

Composite tails are a concern also. FAA certification does not require full deflection capability in both directions I was told as was the case with AAL A300 in New York attributed to pilot error. Old Boeing iron however, has this capability: engineering far exceeding the minimum FAA certification specification. A few 747 era Boeings and DC-8's survived jet upsets that resulted in supersonic dives. I'm not sure todays composite airframes could do it? Are you?

These are just my opinions only. I never flew the A330.

Crunch - Out

[ByteJockey]

I've seen a few suggestions that the weather radar may have failed. However, the crew is supposed to have sent an ACARS message saying they were flying through CB. Bearing in mind the flight was at night, doesn't that suggest that the weather radar must have been functional? Or could they have detected the CB visually even at night?

[GMDS]

There is too much fixation on what exactly must have happened in this accident. Experience shows that it takes up to 5 contributing factors to end up in a fatal accident. One might be governing, but the others, if sequential or additional, contribute the rest to make it unsurvivable. Accidents like this one, with so little hard evidence up to now, and most probably for a very long time, are extremely hard to analyze in this respect.
Another thing we see is the debating of one single factor on a general, sometimes theoretical level. Sure enough every pro has his view of the things, but even he is basically a Monday morning quarterback, as the decision during the game is required on the spot, without handy close-up replay function. Any action or decision might be the third best option theoretically, but could be the best, worst or only one in real time.
The Swiss cheese model tells us that the holes might become lined up and that we must constantly try to mitigate this. The holes might look random from all our different angles, but they might have just aligned for the poor crew in question. Their angle of the circumstances is very difficult to duplicate.
Such factors/ holes would typically be: Crew training, crew experience, crew composition, sops, aircraft design. Subsequently flight planning, severe weather, fuel/load decisions, company pressure, fatigue and on top of that your bad day and simply bad luck.
There is the tendency to try to blame one or maybe two factors, but to actively forget the others.
It is a matter of perspective and interest. Keep that in mind.

[Cacophonix]

One hypothesis that has been raised in this forum is that severe icing might have had a role to play in a series of events in this disaster. How severe would airframe/pitot icing have to be to overwhelm the A330’s anti icing and de-icing systems? Are there any icing case studies on the A330 or other Airbus aircraft? What weight do the Airbus pilots on this forum give to this hypothesis?

I am hard pressed to find any reportable severe icing cases on medium to large commercial jets (of any type) in the last ten years (regional turbo props etc. being the exception).

[crjo]

Hello all,

Quote from bugg smasher:

a thorough weather brief from a competent dispatcher, [...] the very recent addition of an in-cockpit internet connection that provides us near real-time satellite and radar composite snaps of severe weather areas

I fly for Air France, and both these things are NOT available to us...

We do have SATCOM though, and regularly receive wx advisories from our Ops during flight, warning us of CAT, severe wx or other flight risks ahead of us.

There seems to be no doubt that the A/C entered a monstruous CB, but the only question, to which we probably will NEVER have a definitive answer is : How did they end up in there ?

ALL crewmembers were very thorough professionnals, one of the F/Os even had responsabilities as a "Pilot-on-watch" at our Operations center, and was extremely aware of the dangers of such flights (as were - no doubt - the other two, which I didn't know personnaly...).

As we all know, it's never just one thing... It's a sequence of events...

[BOAC]

While PJ2 sleeps, may I inject yet another call on his behalf for some sanity on this thread?

We need more reliable info on the supposed 'ACARS' messages and MEL items for starters. Regarding 'catstrophic event' theorists, the info on the 'ACARS' messages we have indicates a slow but steady degredation of the systems over some 14 minutes (at least) with ACARS system power for all of that time.

I find it surpising that there has been no mention here of 123 (or even 121) chat regarding the ride and weather cells which I would have expected (and made myself) on that route. Do none of our posters have any info on actual route conditions at the time? Did any 'similar' traffic make significant route deviations?

[Farfrompuken]

I still think people are losing sight of the fact that when transiting the ITCZ, sometimes there is NO ideal way through. You've gotta punch your way somehow and that route depends on what looks better on the radar and outside.

But we don't, and may never, know what happened

Let's wait to see what the profesional crash investigators say, rather than rattle off all manner of tosh.

[Captain-Crunch]

rubik101,

Why do you keep saying the "B" word? There is no evidence at all of that. There is, however, evidence of severe convective weather on the route. There is, however, evidence of the aircraft being rather High in Coffin Corner early in the flight (FL350 candidate for jet upset.) There is radar evidence of an enormous mature cell (and almost all, mature cells have associated lightening contained within them whether or not a lightning detector on a spacecraft or a weatherman in Atlanta can see it is unimportant.) All of us who have penetrated them can tell you they are full of lightening, St Elmos fire, extreme turbulence, massive up/down drafts, ice beyond normal design limits... etc, and when you exit a big one don't just punch out at a 90 degree angle or you might break the wings off. It is my humble opinion, as a guy who flew before wind shear was even a word, that you should exit at a 45 angle to the cell wall.

Naturally, don't penetrate and you won't ever have to make that choice. But riding around on autopilot all the time pushing buttons does nothing to sharpen your hand flying skills for a possible situation like this when you will need it the most. I am simply appalled by the autopilot-dependent culture in many flight departments.

Crunch

[Munnyspinner]

ADFS,

This is probably one for a new thread anyway and there is every chance this ppost will also be deleted. However, the seemingly arbitrary removal of perfectly reasonable postings speculating as to the cuase of this accident gives the impression that the mods are exerting editorial control.

It would appear, at the moment, that the wreckage trail is pointing towards a sudden and catastrophic failure in the airframe. The ACARS message indicates an sudden depressurisation but this may have been triggered by factors other than that which has been suggested by a senior AF pilot. A lightning strike that may also have disabled the radar and comms could caused a breach in the fuselage which would iniate an explosive decompression.

It is assumed that the crew were unable to broadcast any mayday and it was therefore a sudden event that caused the loss of A/C and all on board. If Comms were damaged by lightning the crew may have had no means to relay a message in any event. Even with the highest workload, there were three crew and it is inconceivable, in my mind, given their location over the sea and hundreds of miles form the nearest landfall, that communication would not have been one of the highest priorties, irrespctive of what else was going on. Only recovery of CVR will confirm actual circumstances.

Everything here points to a freak accident caused by a confluence of events - the perfect storm. The sooner that the variuos theories are ruled out and the causes are identified the better for everyone.

[etrang]

the 'ACARS' messages we have indicates a slow but steady degredation of the systems over some 14 minutes (at least)

Why 14 mins? The first and last messages have been reported 4 mins apart.

[MikeAlpha7]

I have worked on installing the latest ACARS system in my airline and the amount of information that one can get from ACARS is mind boggling. In fact I would dare to say that is as good as FDR , but obviously lacks the CVR capability of recording voice.

ACARS works with VHF or SATCOM , there is also a HF data solution but it is not common and only few airlines use it.

As far as the AF A330 is concerned , I have no doubt that they had SATCOM as the postion of the A/C over the ocean was away from any ground base recivers . hence MCC or Operation Control could get all the messages from the stricken aircraft.

One thing that remains to be seen is how Air France has selected to operate the ACARS on this route. Transmissions using SATCOM are expensive, many airlines are selctive in the amount and the frequency of information that is transmitted by ACARS using SATCOM. Some configure the system to collect all the data and when they reach a VHF station , it dumps all that data to base using the much cheaper rate.

A very good question was raised about the G force . YES , ACARS can send this information as well and it will be quite helpfull in the crash analysis. Whether the G force was recieved by Air France or not is not clear.

ACRAS is the primary tool for Aircraft Tracking with many airlines operations control centers. However , again it depends on how the airline has configured the system. Obviousley it is a waste of money to send postion fix every five minutes (specially under SATCOM) , neverthanless ACARS is second best flight tracking system after Radars with an added advantage that a Radar has certain range while ACARS is not necessarily bound by range limitation.

.

[Phalanger]

'There are five electricity supplies on the plane and they would all have to fail.' He said a bomb was the only logical reason for why the captain failed to send out a mayday call.

I wrote the same hypothesis at 0223 yesterday but that and two further posts were deleted. As will this one, I have no doubt.Because the messages from the computer are relevant, not the chance of some occurrence. De-pressurisation was the very last, along with vertical speed. There was 4 minute spread of computer and system failures before that.

I'm sure he has also flown those same number of years without a bomb on his aircraft. But there has been system failures before, as well as bombs. So you must look at just the information on this crash.

[ByteJockey]

@BOAC, I can't remember where I saw it, but there was a report that other flights were in the area at the time, both ahead, behind and parallel - if memory serves, one was a DHL freighter. The report also said that none of the flights that might have heard from AF447 picked up anything. It does seem a little puzzling that the crew sent out an ACARS message but no radio traffic was heard, although the fact that the first ACARS message was sent on the hour suggests it may just have been a SOP-scheduled message.

[AMF]

For you Airbus 330-200 drivers out there (or anyone else who actually flies for a living at the higher flight levels)....

FL 350 and still heavy with weight of 8 hrs of fuel plus reserves remaining for the trip.

Autopilot disconnect (for whatever reason, the ACARS says this was the first event) , now hand flying in Alternate Law. No overbank or (my understanding) buffet protections. Moderate, or possibly severe turbulence in the mix if that's what kicked off the Autopilot in the first place due to pitch or roll overlimits. Now your prime consideratoin is to keep the aircraft within the aerodynamic buffet boundaries.

Have any of you hand-flown an Airbus (or other aircraft heavy with fuel) at those flight levels even in smooth air? What about in rough air and may have to maneuver...or outside forces are doing the maneuvering/airspeed fluxuations for you and you're fighting to stay withing the (small at FL350) flying envelope/Q-corner?

The problem with > moderate turbulence when you're high and heavy isn't about shearing off parts of the aircraft that in turn cause it to come down, it's about being able to keep it flying especially if the Autopilot gives up due to conditions exceeding it's capability to keep up with changes of axis/and or airspeed and suddenly hands control over directly to the pilots, where that pilot may have little or no experience controlling his wallowing aircraft in that high-altitude, small margin for error realm of fight on a good day, let alone a dark and stormy night.

Perfectly good airplanes have succumbed to the Laws of Aerodynamics with no faults, structural failures before the fact, lightning strikes, b-word events, etc. etc. etc. in the mix. Just because in normal conditions we don't run up against the boundaries of those Laws doesn't mean they disappeared...they're still there waiting to bite. And we are paid NOT to run up against those boundaries and avoid situations where we might, and this is what we routinely do as professionals.

Take a jet aircraft and put it high, heavy, and run it through rough enough air and the Laws of Aerodynamics are waiting. I assume they still teach these things for those that haven't experienced it. They really aren't kidding.

[MikeAlpha7]

It seems many people here are looking at the weather as a probable cause.

I have flown the A340 (but not A330) for many years in similar tropical weather on the other side of the world , Africa , Far East and India where the same weather pattern exists.

Towering CB's , Massive CAT's , rain and precipitation of huge magnitudes are quite common. No pilot in his right frame of mind will attempt to penetrate the worst of such weather and in this day and age , the pilot has plenty of information and warning to prevent him from going through such weather.

If , and I say a BIG IF , weather is considered as a major factor , then surely there must have been a failure in the cockpit mainly the weather radar, that sent the crew into a very active cell. OR , the radar failed to pick up these activities !!!!

Our old A 340's ( no more flying) had a problem with weather radars. If I can remember rightly , we had problems with the shallow band of vertical coverage of the radar. It could not pick up the significant weather when it was tilted beyond certain degrees , up or down. Apparently it was a software issue , which was supposed to be fixed in the newer generations of A340 and A330.

[OleOle]

MikeAlpha7

does the ACARS "know" whether the SATCOM uplink is working, and would it buffer the mesages if it "knew" the link is unservicable for the moment and sent them at a later point in time when it "realises" the link is up again?

Or in other words: If messages are received during a four minute period of time by the operator, does that necessarily mean, the technical incidents which triggered the messages did happen also within a four minute period of time?

Can messages be lost during transmission, such that the message set received by the operator is actually only a subset of what was sent by the a/c?

Probably that kind of questions is what people in Paris are trying to sort out in the the moment.

[Fly747]

Quote;
"I still think people are losing sight of the fact that when transiting the ITCZ, sometimes there is NO ideal way through. You've gotta punch your way somehow and that route depends on what looks better on the radar and outside."

I have to disagree with Farfrompuken's comment above. In extremis if there is no way through then you have to divert or go back if you can't go around the storm. That is what we are paid to do if necessary.

[jauh]

Presumably any TAT anomalies could affect the ADC and ultimately the flight control system. However many of these systems have internal monitors, data cross comparators and validation routines which could eliminate erroneous information, although possibly degrading control system performance.

Not when your ports are frozen over and only to a degree - remember Aeroperu 603 (http://en.wikipedia.org/wiki/Aeroperú_Flight_603)? Granted, that was a B752, but you can only do so much with conflicting info... I had mentioned pitot-static failure before (http://www.pprune.org/rumours-news/375937-air-france-a330-200-missing-10.html#post4970960) AF did, purely based on ACARS messages, but nobody paid any attention to it...

[REO]

As an ex 340 "operator" and now a happy -400 "driver", I must aggree with AMF's post...
Put all that together, and now add "dual input" as both guys upfront grab the stick, as the autopilot kicks out, and try to correct the jet upset!!
As you know, "dual input" doubles, or cancels out the actual stick position

A bad day for all.

RIP.

[AIEXPATS]

For the A330/340 rated - a question.
This will be the next A330/340 sim LOFT session once the facts come out!
Is this "advisory" an ECAM message also?
Looking at all these ACARs messages prior - what electrical power losses would cause the Controllers to default/fail?
If for example all power is removed - does the system enter in FAILSAFE closed position for the valves (operating the Ditching Valve)?
Is there an situation you can think of where the Outflow Vlv/s would not close fully to control the cabin altitude - perhaps causing this vertical speed advisory?
Meaning if the sequence of events, ECAM warnings, etc. has the 3 cockpit crew dealing with all the previous issues, now comes an eventual CABIN HIGH ALTITUDE.
The next problem for the Crew would have been a "controlled" expeditious (2-3000 ft/min) or maybe even an emergency descent (shy of MMO with Speed-brakes)?
As we know that would make it extremely difficult to avoid and very easy to literally drop right into even more severe weather and the eventual turb., icing, spacial orientation and performance issues.

[dougydog]

AMF,

How much above `optimum` do you think he was at the time?

On the 767 entering an area of severe turb you are recommended to be 4000` below optimum for max comfort away from stall mach buffet etc...What is it on the 330?

I remember in the early days of the 76 some of the older chaps would go as high as possible- sometimes 4000` above optimum- used to feel like being on a knife edge. Doesn`t happen on my flt deck I can tell you!!

[Knutsford]

The "failure" of the Captains TAT probe would cause a double ADR fault.

The result of this is the disconnection of the autopilot and a reversion to Alternate (2) Law.

This was quoted in an earlier post as the first two symptoms transmitted via ACARS.

As I understand it, the health of the said TAT probe is not monitored, so this would not be evident.

[fireflybob]

Until they (hopefully) get the FDR and CVR who knows?

However we do have a proven a/c (ok yes there have been a few incidents as with any type), an experienced and mature crew who presumably were well familiar with long haul ops across the ITCZ and the hazards associated with large CBs working for an established company with a good track record.

My opinion on the scant evidence we have so far is that something happened extremely quickly - no distress call was apparently made.

So if I was a betting man I would go with the bomb theory. I just hope and pray they get the recorders from the ocean.

[jauh]

I had mentioned pitot-static failure before AF did, purely based on ACARS messages, but nobody paid any attention to it...
Wow maybe you should contact BEA and tell them you've figured it all out already.

Iced up pitot/static probes on a modern airliner at FL350, lets get real please.


Well, what will knock off a/p, switch the opmode of FbW and lead to a stream of ADIRU failures? If you're gonna dismiss ideas, at least do that constructively...

[BOAC]

Why 14 mins? The first and last messages have been reported 4 mins apart. 11:00 p.m. local time — The pilot sends a manual signal saying the jet was flying through CBs — towering cumulo-nimulus thunderheads.

11:10 p.m. — A cascade of automatic messages indicate trouble: The autopilot had disengaged, stabilizing controls were damaged, flight systems deteriorated.

11:13 p.m. — Messages report more problems: The system that monitors speed, altitude and direction failed. The main flight computer and wing spoilers failed.

11:14 p.m. — The final message indicates a loss of cabin pressure and complete system failure — catastrophic events in a plane that was likely already plunging toward the ocean.Purely based on what we have on this thread, the first possible indication of 'difficulties' at 11:00?

[deltayankee]

My opinion on the scant evidence we have so far is that something happened extremely quickly - no distress call was apparently made.


I am not convinced that this opinion is the only explanation. Several posters have already expressed that in the case of extreme trubulence and/or an upset they would be busy trying to fix it and not make distress calls a priority. Just a few posts back someone pointed out that when you are in the cruise with headsets off you might not be able to find the hand mike. And frankly at three hours from the nearest land I don't see what an urgent distress call could do. It is different close to landing where you need ATC help.

[Klauss]

Hi,
does anyone know where the accident happened (lat/long) ?

Hand flying: rarely done at altitude, but not a problem at all.

ITC: seemed stronger 15, 20 years ago, but still well worth keeping an eye on.

Radar: can be difficult to interpret. Remember, radar shows essentially water.
Water falls down when the sun goes down (mostly). What remain are weak
echos of possibly still strong turbulence.

Satellite-pics: not available in real time in the cockpit. Don´t know if
they were available to the AF-Crew before departure.

Best, Klaus

[MartinM]

Purely based on what we have on this thread, the first possible indication of 'difficulties' at 11:00?

I believe that the problems already started earlier. But during this 4 minutes, there was the total loss off control. The cabin VS warning would light up if the pressurization system is not able to maintain indicated cabin altitude, this either to a high rate of decent or ascent. I haven't ever stressed the A340 Level_D Sim that way. So i cannot really tell you how much V/S (positive or negativ) is necessary to force it. I recal some earlier statements, +/-1800. Well. I guess that was the moment were the aircraft was falling out of the skies and the reason why V/S was exceeded and why the cabin V/S popped up.

11:14 IMHO was the moment when the aircraft on its way down from 35'000ft broke up in parts. Thats when there was nothing to comminicate anymore by ACARS

ACARS unfortunatly is not telling us what happened in the minutes before loosing control.

Cheers
Martin

[eazyflite]

I am wondering about that there is no discussion about that within 2hours more than 5 Airlines flying on the same track through or better to say around the tropical system eg. IB there were scheduled 10min later. How they did manage the circumnavigation around the storm? Or did they delay the departure? Was there no air to air talking?

[Gergely Varju]

About 14 minutes between messages theory: If there is a problem, a long typed message isn't priority, and it is sent at 11:00, which would make it even more likely that it is something sent on regular basis. If there would be problems at this time, when they have time for typed messages, they would have time to decide deviate, return, etc. with many options. And if things would get worse (slowly) in the next 14 minutes we would have reasons to expect to see more communication attemtps, etc.

Why no MAYDAY or PAN-PAN message sent to ATC? We don't know the exact reasons, even if we assume they could contact ATC somehow, and the storms didn't make it impossible, their radio was working, sending such messages are urgent if you expect ATC can offer some assistance.

[DVD]

To eazyflite (http://www.pprune.org/members/110512-eazyflite);

From what I hear in another spanish forum, the IB flight was just a couple minutes behind the AF in the same track, although I think they were I little higher 370, they didn´t go thru the TS, the deviated a lot to avoid it, and the ride was quite smooth....

[theballetbrusque]

ALTERNATE LAW If Multiple Failures of Redundant Systems occur, the flight controls revert to Alternate Law.
The ECAM displays the message: ALTN LAW: PROT LOST Ground
Mode The ground mode is identical to Normal Law. Flight
Mode
In pitch alternate law the flight mode is a load factor demand law similar to the Normal Law flight mode, with reduced protections.
Pitch alternate law degrades to pitch direct law when the landing gear is extended to provide feel for flare and landing, since there is no flare mode when pitch normal law is lost.
Automatic pitch trim and yaw damping (with limited authority) is available.
Turn coordination is lost.
When pitch law degrades from normal law, roll degrades to Direct Law - roll rate depends on airspeed. Protections
All protections except for load factor maneuvering protection are lost.
The load factor limitation is similar to to that under Normal Law.
Amber XX's replace the green = attitude limits on the PFD.
A low speed stability function replaces the normal angle-of-attack protection
System introduces a progressive nose down command which attempts to prevent the speed from decaying further.
This command CAN be overridden by sidestick input.
The airplane CAN be stalled in Alternate Law.
An audio stall warning consisting of "crickets" and a "STALL" aural message is activated.
The Alpha Floor function is inoperative.
The PFD airspeed scale is modified:
VLS remains displayed
VALPHA PROT and VALPHA MAX are removed
They are replaced by a red and black barber pole, the top indicating the stall warning speed VSW
A nose up command is introduced any time the airplane exceeds VMO/MMO to keep the speed from increasing further, which CAN be overridden by the sidestick.
Bank angle protection is lost.
Certain failures cause the system to revert to Alternate Law without speed stability.
Yaw damping is lost if the fault is a triple ADR failure. ABNORMAL ALTERNATE LAW Abnormal Alternate Law is activated if the airplane enters an unusual attitude, allowing recovery from the unusual attitude.
Pitch law becomes Alternate (without autotrim or protection other than Load Factor protection).
Roll law becomes Direct law with mechanical yaw control.
After recovery from the unusual attitude, the following laws are active for the remainder of the flight:
Pitch: Alternate law without protections and with autotrim.
Roll: Direct law
Yaw: Alternate law
There is no reversion to Direct law when the landing gear is extended.

[eazyflite]

well, also a lot of Flights ex GRU were flying the same Track, if they were all deviating the TS, it seems to me either the WX Radar was U/S, or maybe the Pilots felt into sleep. Nobody would fly into the red Patches. Nobody could overfly the TS. (Tops up to FL500)

[nyt]

For what it's worth, "Le Monde" claims through a unnamed source that the plane was overspeed and that an airbus directive will be published ASAP regarding speed management in rough weather.

[carzerdan]

Please, can you tell me what is the FL limit for an A330 with one airconditioning pack trip off?

Do you know how much would be the cabin rate change in that condition, at FL 350

Another question: does de ACARS send message if the A330 is losing power in one or two angines (eg. due to ice build?)

Hard turbulence, with ice build up is a very bad scenary. Is is not?

Cheers, Carlos

[NARVAL]

I take the liberty of posting my previous message again, if I may...
Although the initial failure report in the automatic message seems to have been about electrical problems (I do not know which) and the "tree" of possibilities of systems degrading from there is a vast one, I have kept in mind since the sad news ot the accident the following facts:
the A330 is a beautiful aircraft but it has shown, again and again , very susceptible to probes icing, with the deicing system on auto (numerous reports). This leads to very rapidly presenting the crew with a very lame aircraft to say the least (I give you a factual example below, recent, on an A330, without comments). This has happened at high cruise altitudes, with no ICE alarm, with the heating on AUTO, and out of clouds in some cases...
"Light tutbulence. The speed indication on the right PFD falls suddenly from 280 to 100 knots in red tape for a few seconds Almost immediately the speed on the left PFD falls to green dot minus 15 knots with a speed trend of minus 50 knots. Red alarm A/P OFF ADR
DISAGREE, IAS DISCREPENCY, ALTN LAW PROT LOST, REAC W/S DET FAULT.
Then amber alarm RUD TRV LIM FAULT.
Then STALL STALL STALL with Toga Lock indication.""
The crew changes flight level, the captain pilots with the stand by instruments,
The speeds become normal again.
The status after that:
amber crosses on PFDs
W/S DET FAULT, ALT LAW PROT LOST, ADR DISAGREE et F/CTL RUD TRV LIM FAULT (2
NOGO).Plane in Alternate law
This shows how an unconfortable event (loss of airspeed indication) that would have been minor in, say , an A300, becomes a major headache in those very sophisticated cockpits. Just for information and not saying that is
a possible explanation...but lose electrics, and apart from dealing with retrieving the generators, you may have that kind of thing loaded on top...
This failure has happened not once but at least four times in the previous year on the fleet.Why do heated pitots ice? In non severe icing conditions, and even out of clouds?I have flown a lot and I would have said that was impossible but the facts are there. It is a documented fact at least on this type of aircraft.We learn from facts and this could very possibly have a direct bearing to this tragic accident.

[Shaka Zulu]

@ carzerdan: can't comment on the pack off max alt for an a330. I know on the 777 if the pack trips off during flight and after appropriate checklist remains off there is no operational limitation. If it is an ADD on the ground than the MEL will give a ceiling restriction for 1 Pack operation.

Cabin Rate will not change IMHO.

ACARS will send a message when it senses abnormal N1/N2/EGT/Oil pressure/Vib/Temp readings (and many more) during any phase of flight.

@ nyt: overspeeding a modern jet is very easily done. The wings are supercritical (another word for extremely slick in layman's terms) and we fly reasonably close to Mmo (max operating mach number under normal conditions). The aircraft however is tested well beyond this Mach No. I know for my aircraft type Mmo is 0.87, the a/c has been tested to M0.95 and it doesn't need any other checks until M0.91 is reached.
Has to be quite an extreme upset with no flight crew actions to get that carried away.

Of course in a vertical up/downdraft situation with no autopilot and 20deg nose down in the coffin corner we are in a WHOLE new ball game.

@ all: long briefs by dispatchers have been removed from most big airline ops. Personally we get a range of maps/charts given to us and it is up to us to decide on the best course of action/possible re-route if it looks bad. Personally it has happened to me that the ''planners'' routed me through an area of possible severe turb for the sake of a 20min quicker flight time.
Although tempting from one angle and sometimes lightly pressured in the current climate and the ''cost is king'' mantra these days, it is easy to accept the routing. We all know that 90% of the time these areas tend not to be that bad. Gladly I did decide for a re-route that day.....

@ all: TAT probe icing is very incipient and extremely hard to diagnose when you haven't been confronted with it before.
(I've had it happen to me but the post will get too long)
BUT: if it happens inside towering Cu/Cb, IMC, Auto pilot disconnect, A/S and Alt anomolies and severe turb....
well that's a situation I rather not contemplate being in....

[Roller Merlin]

Reported today in The Age Newspaper, Melbourne:

Pilot saw 'white light' where Air France flight lost
June 4, 2009 - 8:22PM

The captain of a Spanish airliner claims to have seen "an intense flash of white light" in the area where Air France Flight 447 was lost, the El Mundo newspaper said today.

The co-pilot and a passenger on the Air Comet flight from Lima to Lisbon also saw the light, it said, adding that a written report from the captain has been sent on to Air France, Airbus and the Spanish civil aviation authority.

"Suddenly, we saw in the distance a strong and intense flash of white light, which followed a descending and vertical trajectory and which broke up into six segments," the unidentified captain wrote.

The Air Comet flight's position at the time was at seven degrees north latitude and 49 degrees west longitude, whereas the Air France flight was estimated to be on the equator and 30 degrees west longitude, El Mundo said.

"Given the coincidence of time and place, I bring to your attention these elements so that they may be, possibly, useful in casting a light on the facts," the captain wrote.

The Air France jet went down on Monday during a flight from Rio to Paris with 228 people on board.

Air Comet is a Madrid-based airliner that mainly flies long-haul routes between Spain and Latin America.

AFP

[Rananim]

Practically impossible to say anything constructive with what is available but surely speed(low or high)must figure highly.

For what it's worth, "Le Monde" claims through a unnamed source that the plane was overspeed and that an airbus directive will be published ASAP regarding speed management in rough weather.

This must be their starting point for this investigation..As you approach rough air,you reduce to Va which puts you halfway between low speed and high speed buffet on the speedtape.The higher you are the closer these two will be(hence the reason for flying 2k below opt alt when turbulence is expected).So less margin to counter any speed excursion caused by turbulent air penetration.If you lose electrics concurrently,then you will have to rely on standby ASI which will give IAS only,so one of the first things a pilot should mentally check approaching rough air is the IAS equivalent of Va in case he has to fly it manually.The key is accepting alt excursions and concentrating on att vs speed.CWS R and CWS P are recommended but of course you need the AP.As with so much in flying,speed is often the killer.

All comments made with reference to Boeing aircraft.I cant comment on how the scenario plays out in a scarebus.But a plane is a plane is a plane.

[vetles]

In response to nyt regarding overspeed?

" For what it's worth, "Le Monde" claims through a unnamed source that the plane was overspeed and that an airbus directive will be published ASAP regarding speed management in rough weather. "

I believe the point was that the A/C might have reduced its speed too much:

"The first thing you do when you fly into turbulence is to reduce speed to counter its effects. If you reduce speed too much you stall," retired pilot Jean Serrat explained to AFP."

Crashed Air France jet flying at 'wrong' speed: Report- Politics/Nation-News-The Economic Times (http://economictimes.indiatimes.com/News/PoliticsNation/Crashed-Air-France-jet-flying-at-wrong-speed-Report/articleshow/4616809.cms)

[averow]

Very interesting point. One could envision such a system being created, then acquiring mostly benign information up to the point of the very rare catastrophe, at which point the parameters we really need (when reconstructing events or faults in a post-hoc fashion) are not acquired due to electrical catastrophe on the vehicle or in the immediate environment of a thunderstorm.

NASA was able to glean a lot of information after the Columbia and Challenger accidents from data telemetry but those were obviously densely instrumented vehicles with dedicated data acquisition facilities groundside. The bandwidth and storage issues with trying to do the same for hundreds of routine passenger flights would be staggering IMHO. :cool:

[Farm gate]

A previous poster stated that probe icing in the A330 was not likely. I have experienced what i think now was TAT probe icing in the A330 whilst deviating around a CB. The TAT increased by 30 degrees C, the FADECs limited the amount of thrust available and the VLS and MMO limits moved towards each other limiting the range of speed available. Last year two A330s operated by an asian carrier suffered air conditioning pack shutdowns within an hour of each other within a couple of hundred miles of each other. The failures, i understand, were blamed upon a large increase in the TAT, the aircraft were deviating around a typhoon at the time.

[OleOle]

I have been talking with the captain of the IB flight that was 10 minutes behind the AF. Here you can find my conversation. Apuestaforo - Ver post - Accidentes aéreos (http://www.apuestaforo.com/showpost.php?p=7792&postcount=82)Interesting. When the IB 10 minutes behind reached TASIL everybody was allready calling out for the AF, so it must have been clear quite early that it was missing/lost.

[Wiley]

Whilst I agree with Klauss' comment that hand flying is rarely done at altitude, I can't agree that it presents "not a problem at all".

Even for a pilot with high handling skills - (a descriptor that I think, if we were being honest with ourselves, very few of us, in these days of maximum use of automation, would lay claim to) - flying at high altitude, even if not in Alternate Law, can be a very mushy can of worms, even in smooth conditions.

In an area of severe turbulence, hand flying at high altitude is not something I'd like to have to do, particularly with such a narrow speed band as the unfortunate Air France crew presented with.

[fireflybob]

2 or 3 days ago on BBC Radio 4 they were interviewing someone (can't recall name etc) from one of the organisations who have previously recovered FDR/CVRs from the ocean. Whilst admitting that the recovery was challenging he was confident that recovery was not only feasible but could and would be achieved. At the end of the interview anyone listening would be left in no doubt that recovery of the recorders was a certainty.

On a slightly different tack who has title (legally) to the recorders? If the official body deemed that recovery of the recorders was not possible and would not be pursued, could others parties do so and if they did are they legally obliged to hand them over to the official investigation?

[md-100]

I guess if FDR/CVR cannot be found.. maybe a new rule for the future could be a mandatory use of ACARS reporting problems with a lot of parameters.... (like a limited online FDR/CVR)

[theballetbrusque]

Air France flight 447 delayed by bomb threat
By Editing Staff http://forums.canadiancontent.net/articles/photos/phpjVxnci.jpg
Media sources have learned that Argentine media reported on May 27 that an Air France (http://www.canadiancontent.net/profiles/France.html) flight traveling from Ezeiza Airport in Buenos Aires, Argentina (http://www.canadiancontent.net/profiles/Argentina.html) to Paris, France, was delayed after the airline reportedly received a bomb threat, just days before Air France Flight 447 crashed into the Atlantic Ocean.

According to momento24, on May 27, authorities boarded Air France Flight 415, a Boeing 777 en route to Paris and searched the plane for a bomb, but found nothing. They were acting on a threat that had been phoned in. The search lasted for nearly two hours and none of the passengers were evacuated from the aircraft. Air France issued a statement saying the threat was later proven to be "false" and that the plane had only taken 32 minutes to search, and was then allowed to proceed to its destination.

Air France flight 447 delayed by bomb threat (http://www.canadiancontent.net/commtr/air-france-flight-447-delayed-bomb-threat_955.html)

[Optimus-Prime]

Flight 447 crashed and there was a bomb threat days earlier somewhere on the same continent. How the :mad: do they put that together to 'Air France flight 447 delayed by bomb threat' ??? :ugh::bored::confused:

[BOAC]

Relevant? - no. AF447 was NOT delayed for a bomb threat as far as we know.

[OVERTALK]

in his post #718 (http://www.pprune.org/4971555-post718.html)

See the link in that post.

Investigators are saying the aircraft stalled into a loss of control at height (inference being too heavy too high too early)......

in this Timesonline link (http://www.timesonline.co.uk/tol/news/world/europe/article6430398.ece) just released

[MartinM]

Air France flight 447 delayed by bomb threat

No really

Press is kind of dumb sometimes :ugh:

[S.F.L.Y]

I think it is time to stop referring to the bomb issue which is basically incompatible with the ACARS messages: the pressurization fault was the last message and came 4 min after it all started.

The recurrence of control losses due to ADIRU faults and the lack of solutions from the manufacturer is a serious issue still valid today. If this is not the cause of this accident I'm still wondering how these aircrafts are still flying under such circumstances. The sequence of faults generated by ADIRU faults is a major risk of upset aircraft situations, especially at night, in turbulences and IMC. What are we doing about it?

[theamrad]

Posting the b*m* story AGAIN might have been relevant - if it hadn't been posted about a dozen times in the last 20 pages. Same as the link to the meteorological data.
Then again - might not happen if people were A**ed to actually READ the thread.

BOAC - agree with your comments re ACARS messages.

[Safety Concerns]

just for those who are undoubtedly going to run a million miles in the wrong direction with the acars information.

Autopilot disconnect will show on the data regardless of how it was disconnected. So although we know it disconnected we still don't know if the disconnect was manual or automatic.

However considering the multiple ADIRU fault messages less than a minute later one could be forgiven for assuming it disconnected automatically due to the increasing amount of failures for whatever reason.

But this then leads to another issue. Multiple ADIRU faults are unheard of. It doesn't happen unless the aircraft has suffered some extroardinary event.

Make what you will of this FACTUAL information.

[wileydog3]

I will ask this differently...

from the posts, it seems the string of events is
a/c slowed to penetration airspeed in severe/extreme turbulence
loss of pitot input due to icing
failure of ADIRU1 due to lack of input
disconnect of autopilot and reversion to ALT law (no stall protection)
failure of PRIM1 and SEC1 and ISIS
loss of control, possible stall
ACARS message about cabin pressure due to inflight breakup.


(no attribution!)

[skywreck]

"Pues nada, lo prometido es deuda. Aquí os dejo esta primicia mundial recien sacada del horno.
He hablado con el comandante del vuelo de IB que iba junto al AF. Os resumo lo que me ha dicho.
Estuvieron hablando con la tripulación del AF en el aeropuerto de Rio, en la cola del control de pasaportes. Dice que eran muy simpáticos y que se estuvo riendo con la sobrecargo. Eso ha sido más palo todavía para él. Ya en el despacho de vuelos vió que la zona en cuestión estaba complicada por el mal tiempo y decidió echar 2000 kilos más de combustible previendo que tendría que desviarse bastante. Despegaron unos minutos detrás del AF, como casi siempre y ellos subieron un poco más, hasta 350. El AF se quedó a 330. El vuelo iba como siempre sin problemas. Al llegar cerca de esa zona ellos ya estaban a 370 y el AF a 350. Entre INTOL y TASIL había un area muy grande de cumulonimbos que subian hasta 50000 pies, es decir tormentas muy potentes. Él se desvió muchas millas de su ruta para evitar la zona y no sabe lo que hizo el AF porque no lo tenía en el radar, pero cree que se metió en el berenjenal. Su vuelo fué tranquilo y sin turbulencias resaltables. Al pasar TASIL, que ya entras en espacio controlado por Dakkar, todo el mundo estaba llamando al AF por la radio y pensó que se habrían despistado, en nigún momento se imaginó lo que había pasado, por que su vuelo no había sido complicado. No hubo ningún mensaje por radio del AF.
Ha sido un palo para él, haber conocido a la tripulación. Yo le entiendo porque me pasó lo mismo hace años. Estaba en BCN cenando y entraron dos guapas pilotos rubias que conocía. Todos volabamos el avion Fairchild Metro con carga aerea, ellas en una compañía y yo en otra y despues de cenar saliamos a volar, ellas a Bruselas y yo a MAD. Despegaron unos minutos antes que nosotros y cuando despegamos nosotros nos enviaron por un sitio que no era el normal, por lo que pensé que algo ocurria. Al llegar a MAD me enteré que se les había parado un motor y que volviendo a BCN se estrellaron a dos kilometros de la pista."


Oh well, what was promised is a debt. Here a I leave you a world exclusive just taken out of the oven. I have spoken with the captain of the Iberia
flight that was flying near the Air France flight. I will give you a resume of
what he told me.

They spoke to the Air France crew at Rio airport, while in the passport contro queue. They said they were very likeable and were laughing with the "sobrecargo"?, which made this more of a shock for him. While in flight
despatch he saw that the area in question was very complicated due to
bad weather and decided to 2000 extra Kgs of fuel, foreseeing that
he would have to deviate quite a lot. They took off some minutes after
Air France, as usual, but they climbed a little further to FL350. Air France
remained at FL330. The flight went as usual without any problems. When
reaching the zone in question they were already at FL370 and Air France at FL350. Between INTOL and TASIL the was a huge area of cumulunimbus that reached up to FL50, that is to say very potent storms.
He deviated many miles away from the route to avoid the zone but didn't
know what happened to AF because he didn't have it on his radar, but
believes it went into the storms. His flight was quiet and without much
turbulence. After passing TASIL and just entering into Dakar airspace, everyone was calling the Air France flight on the radio and he thought
that perhaps they had lost their bearings, but never for a moment did he
imagine what had actually happened, because his own flight had not been
complicated. There were never any radio messages from Air France.
It has a been a real shock to him having met the crew.
I can understand it, for something similar happened to me some years ago.
I was in BCN having dinner when two very attractive blonde female pilots that I knew arrived. All of us flew cargo on Fairchild Metros but for
different companies.After dinner we went flying our separate ways, they to Brussels and I to MAD. They took off some minutes before us. After our take off ATC sent us on an unusual route and I thought something was
happening. On arrival at MAD I found out that they women pilots had one engine failure and while returning to BCN crashed 2Km short of the
runway.

[Gary Brown]

Overtalk wrote:

Sounds like Belgique was on the right track....
in his post #718 (http://www.pprune.org/4971555-post718.html)

See the link in that post.

Investigators are saying the aircraft stalled into a loss of control at height (inference being too heavy too high too early)......

in this Timesonline link (http://www.timesonline.co.uk/tol/news/world/europe/article6430398.ece) just released


That's not really what the Times story to which you link says; and nor does the Le Monde story on which the Times report is based. In both cases the newspapers are stating that Airbus, with the support of BEA, will issue a recommendation regarding speed. But they don't quote anyone from either Airbus or BEA (except to say that Aibus had "no comment").

Here's the Le Monde original:

L'Airbus d'Air France volait à une vitesse "erronée" et s'est désintégré en vol, selon les messages captés au sol - Société - Le Monde.fr (http://tinyurl.com/p8qyc4)

Airbus devrait publier une "recommandation" validée par le Bureau d'enquêtes et d'analyses (BEA), jeudi 4 juin, destinée à toutes les compagnies utilisant des biréacteurs A330 et rappelant que, en cas de conditions météorologiques difficiles, leurs équipages doivent conserver la poussée des réacteurs et l'assiette correctes pour garder l'avion en ligne.

"Airbus is to publish a "recommendation" approved by BEA, on Thursday 4th June, aimed at all airlines that use the twin-jet A330, reminding them that, in difficult weather conditions, their aircraft must maintain proper engine thrust and attitude to keep the aircraft under control."

Note: I'm no expert in aviation French, so I'm not certain whether "assiette" and "en ligne" are the usual aviation terms for "attitude" and "under control", or whether the journalist is "interpreting" what he or she heard.....

AGB

[ste1ste]

i know about the warnings for the failures of electric's and also the pressure issues what other warning where given by the acars system. how about warnings to the AOC or the AAC?

[protectthehornet]

wileydog


now that scenario I believe...

sometimes you just have to set the power to a known setting(to maintain turb pen speed) and try to keep the wings level and the nose somewhere near the horizon and accept the changes in altitude.

riding the waves as we call it out west.

[TripleBravo]

Lost in Saigon:
You would have "caught the cabin" in descent resulting in a very high descent rate for the cabin.
I admit I did not check the maximum cabin pressure descent rate compared to emergency descent. So - right.

torquebox:
Radomes seem to cop a lot which is why they have such massive lightning diverter strips.
Sorry, I had to be more precise: For sure the radome is subject to lightning (didn't want to say that), but I never came across evidence that this part is more prone than others. The reinforcements of conductors present in the radome is because it is made of glass fibre, which is an insulator. (Would it be conducting, the radar beam would be immediately reflected by the radome.) Similarly the vertical tail leading edge is partly glass fibre, because of the antennas behind.

Phalanger:

It's interesting that spoilers are reported as failing in the last set of messages.
This must be overinterpretation by media with a sound half knowledge. The cited ACARS did report SEC1 to be failed, which controls the spoilers. But: SEC2 is just as cabaple and not reported to have quit. Similarly, I read that the plane would have run by "alternate power" - which they simply mixed up with "alternate law".

blueloo:
Absolutely - but I would tell Air Traffic Control this. Not operations/my company.
If you get through, that is. We only know that there was no chatter recieved. At least I don't know whether they attempted and weren't heard. Perhaps the message - if true - was typed by the third pilot just when they changed shifts?

[One Outsider]

AGBagb

I think you should see the posts by OVERTALK and Belgique, as more of a plug for a certain organisation than anything else.

[wileydog3]

safety concerns wileydog you sum up why pilots shouldn't be making technical decisions.

That is why I ask questions. Not a technical decision but rather a question about the sequence of events.

At PPRUNE we have THE EXPERTs including from pilots with vast experience and experts in other fields related to aviation ( meteorologists, engineers, etc). We also have lots of a lot of wild speculation and that comes with the territory.

But the often made critique of the media is they don't know **** about airplanes. But when questions are asked, they are also berated as some type of goon searching for quick answers. I hope I don't fall into either category but just trying to learn.

I fully respect the sequence of an accident investigation and acknowledge that without the FDR this 24 page thread and other forums will be just speculation and theory but here it can be informed theory.

Thanks for the correction. I appreciate the input.

[Safety Concerns]

wileydog I apologise unreservedly

[wileydog3]

no apology necessary.

But if I remember my A320 and from reading on ADIRUs, there are 3 and one input to the ADIRU is from the pitot/static system. Losing that input would cause a fault and require selecting ADIRU3 to regain information IF ADIRU3 had good info. Correct?

I realize all accidents are the exception to the rule and I have no axe to grind about any manufacturer. I have flown Boeings, Airbus, Fokkers, McDougs along with a number of businessjets. I understand that engineers at one company may have a different philosophy and approach to building an airplane. Not necessarily better but different. I also have yet to find one that fits the scaremongering some offer as to Airplane X is a flying death trap. I also recognize there are personal preferences and parochial biases. But I also remember the two caveats... all airplanes are compromises and all airplanes have strengths and weaknesses. Play to the strength. Respect the weakness.

yes, now maybe a bit trite but ancora imparo

[XB70_Valkyrie]

The recurrence of control losses due to ADIRU faults and the lack of solutions from the manufacturer is a serious issue still valid today. If this is not the cause of this accident I'm still wondering how these aircrafts are still flying under such circumstances. The sequence of faults generated by ADIRU faults is a major risk of upset aircraft situations, especially at night, in turbulences and IMC. What are we doing about it?

Best post of the day.

If conditions (ice, CAT, whatever) overwhelm the ADIRU and upstream systems and cause a reversion to alternate law (and distract the cockpit with error messages) and remove the very protections (overspeed, stall) you really need in those conditions, isn't that a pretty bad situation to deal with?

There are going to be two big questions for the investigation to answer:
1) why did the crew get so close to a CB (wx radar etc)
2) why was the crew unable to prevent the a/c from entering an aerodynamic condition (overspeed?) where it broke apart

[Safety Concerns]

One should be clear on what an ADIRU actually does.
The air data part does not directly affect flight controls.
The Qantas scenario was cause by the IR part.

3 completely separate and independent ADIRU's and 3 completely separate and independent pitot probes and 6
(3 pairs) of completely and independent static ports.

Under normal circumstances a complete failure of one air data system in flight would be of no significance whatsoever.

Furthermore the air data part is completely independent from the IR part. So losing all air data on one system has no effect on control and stability as far as the flight controls are concerned. In fact you can even switch off the IR part or the Air data part independently.

The reason for it being called an ADIRU is that both independent parts are in the same physical housing.

[Wader2]

Severe turbulence can be experienced 10 miles from the Cb either to the side or above. To assure safe ITCZ penetration and keep 10 miles clear of the severe turbulence would require a corridor in the region of 30 miles wide.

As you enter the valley between Cb who knows what may happen as you get further into the system?

[hellsbrink]

Am I the only one having trouble believing that "report" from The Age?

According to my reckoning, it would mean the "witnesses" were able to see not only a "white light" but 6 distinct objects falling at a distance in excess of 2000km when, by other things said, the AF craft was in the middle of a very big cloud.....

That's some eyesight...


(Added.. Translation of the El Mundo report says the co-pilot saw a "white flash" which then descended and faded after 6 seconds, not something that broke up into 6 segments. That could be a lot of things, and shows how pee-poor reporting can make people go "THIS IS WHAT HAPPENED!!". Don't believe everything in the press)

[MartinM]

According to my reckoning, it would mean the "witnesses" were able to see not only a "white light" but 6 distinct objects falling at a distance in excess of 2000km when, by other things said, the AF craft was in the middle of a very big cloud.....


Who said 2000 Km?

Iberia was flying behind the AF

Cheers
Martin

[Dutch Bru]

04/06/2009 - 10h08 (Brasilia time=15h08 GMT)


Air Command announced that during the searches conducted in the early hours of today (04/06), an R-99 aircraft of the Brazilian Air Force (FAB) has identified new items of debris near the cliffs south of St Peter and St Paul.


During the night, five other military aircraft took off from Natal-RN into the search area (three FAB C-130 Hercules, one USAF P-3 Orion and one French Falcon 50).

For the first time during the operation, a H-60 Black Hawk helicopter, based in Fernando de Noronha (PE), takes part in the search missions 110km northeast of the archipelago.

Besides the visual exploration of the area in which new debris has been detected, the aircraft involved will coordinate the direction of two Brazilian Navy vessels that are in the area to retrieve debris.

[thcrozier]

"la sobrecargo"

That is spanish slang for a female flight attendant.

[Brosa]

It has been suggested that an iced up pitot/static probe could have caused erronious values being sent to the ADIRU's.

Couldn't a lightening strike have damaged a probe, causeing similar problems?

[FRACharley]

ATSB TRANSPORT SAFETY REPORT
Aviation Occurrence Investigation AO-2008-070
Preliminary
In-flight upset
154 km west of Learmonth, WA
7 October 2008
VH-QPA
Airbus A330-303

I have this doc in PDF format but don't know how to get it to you.

[hellsbrink]

Who said 2000 Km?

Iberia was flying behind the AF

Cheers
Martin

Positions stated in the "report" (7°N 49°W for Air Comet, 0°N 30°W for AF) plotted on Google Earth gives you a separation of around 2112km with the AF at around 96° to the right of the AC position.

Check it yourself if you don't believe me. And, after all, I can't see anyone leaving Lima and being able to be on the same heading as the AF craft which had left Rio.....

[Lost in Saigon]

ATSB TRANSPORT SAFETY REPORT
Aviation Occurrence Investigation AO-2008-070
Preliminary
In-flight upset
154 km west of Learmonth, WA
7 October 2008
VH-QPA
Airbus A330-303

I have this doc in PDF format but don't know how to get it to you.

Try here: http://www.atsb.gov.au/publications/investigation_reports/2008/AAIR/pdf/AO2008070_prelim.pdf

[el_visigodo]

Un piloto dice que vio caer un 'destello de luz blanca' donde desapareció el avión francés | Mundo | elmundo.es (http://www.elmundo.es/elmundo/2009/06/04/internacional/1244097992.html):

"Air Comet estaba a siete grados al norte del ecuador y en el meridiano 49 oeste."

This is 7N 49W.

According to Tim Vasquez http://www.weathergraphics.com/tim/af447/ the estimated crash site is near 3.290N, 30.357W

[Dutch Bru]

The French investigation bureau BEA has denied any forthcoming publication, as announced in Le Monde, of a recommendation to A330 operators and crew on the aircraft speed handling during turbulence. "It is not a matter for today", denied a BEA spokesperson. "The BEA has announced that it intends to communicate regularly and not to delay publication of information that the investigation team has validated" but today "there is no information", the spokesperson said.

[spagiola]

Who said 2000 Km? Iberia was flying behind the AF

There are two reports from Spanish pilots being discussed, hence the confusion.

One is from the pilot of an Air Comet flight from Lima to Lisbon (http://www.pprune.org/rumours-news/375937-air-france-a330-200-missing-88.html#post4973668), quoted in The Age, who claims to have seen "an intense flash of white light" in the area where Air France Flight 447 was lost. This is the one whose distance from AF447's position is being questioned.

The other is from the pilot of an Iberia flight from Rio to Madrid that departed just after AF447 (http://www.pprune.org/rumours-news/375937-air-france-a330-200-missing-89.html#post4973956), quoted from a personal e-mail of unknown provenance. This flight was obviously much closer, though the pilot mentions deviating quite a bit to avoid the cbs. This pilot reported a lot of calls to AF447 once he was on Dakar's frequency after passing TASIL.

[Lost in Saigon]

Un piloto dice que vio caer un 'destello de luz blanca' donde desapareció el avión francés | Mundo | elmundo.es (http://www.elmundo.es/elmundo/2009/06/04/internacional/1244097992.html):

"Air Comet estaba a siete grados al norte del ecuador y en el meridiano 49 oeste."

This is 7N 49W.

According to Tim Vasquez Air France 447 - AFR447 - A detailed meteorological analysis - Satellite and weather data (http://www.weathergraphics.com/tim/af447/) the estimated crash site is near 3.290N, 30.357W

This is what the relative positions would look like.

Great Circle Mapper (http://gc.kls2.com/cgi-bin/gc?PATH=lim-n7w49-lis%0D%0Ario-cdg%0D%0An7w49-n3.29w30.4%0D%0A&RANGE=&PATH-COLOR=red&PATH-UNITS=nm&PATH-MINIMUM=&MARKER=1&SPEED-GROUND=&SPEED-UNITS=kts&RANGE-STYLE=best&RANGE-COLOR=navy&MAP-STYLE=)

http://gc.kls2.com/cgi-bin/gcmap?PATH=lim-n7w49-lis,rio-cdg,n7w49-n3.29w30.4&PATH-COLOR=red&MARKER=1


LIM (12°01'19"S 77°06'52"W) 07°00'00"N 49°00'00"W 2028 nm
07°00'00"N 49°00'00"W LIS (38°46'53"N 09°08'09"W) 2875 nm

RIO (22°54'S 43°14'W) CDG (49°00'35"N 02°32'52"E) 4950 nm

07°00'00"N 49°00'00"W 03°17'24"N 30°24'00"W 100° 1135 nm

That is too far to see anything other than a metor. (probably was a very big exploding meteor)

[MartinM]

Thanks. Thats explains it.

[selfin]

The Brazilian Minister of Defence suggests this would tend to rule out a bomb.

http://img231.imageshack.us/img231/2645/afa332fgzcpatlantic0906.th.jpg (http://img231.imageshack.us/my.php?image=afa332fgzcpatlantic0906.jpg)

Kerosene slick, photo by Força Aérea Brasileira.

[Gary Brown]

Dutch Bru wrote:

BEA denies advisory notice "today"
The French investigation bureau BEA has denied any forthcoming publication, as announced in Le Monde, of a recommendation to A330 operators and crew on the aircraft speed handling during turbulence.These "chinese whispers" are getting worse! Here on PPruNe someone quotes The Times as saying investigators are concerned with AF 447's speed. The Times doesn't actually say that, but gives as its source for a similar story the French newspaper Le Monde. Reuters run the same story, with the same reference to Le Monde. Le Monde doesn't source the story to "investigators" either, but gives as its source the Brazilian "serious newspaper" 'Estado de Sao'. But the Estado de Sao Paulo doesn't give any "investigators" as a source either. Indeed, the Estado story is datelined Paris and *gives Le Monde* as its source for the "investigators" and "speed" story!

:ugh:

[Will Fraser]

selfin #914

With respect, and no wish to even bring up the possibility, I would point out that TWA 800 experienced an "explosion" at ~15,000 feet, with a full load of fuel (except for the Center tank). The debris field included massive amounts of jet fuel and many fires on the Ocean's surface. While it wasn't a "device", I would suggest that even a small explosion (of any kind) at the altitude and environment 447 found itself may have opened the Belly, produced the "debris field", and while not "catastrophic", it could have caused an upset in aerodynamic integrity, and a loss of control.

[TripleBravo]

KRviator:
The aircraft involved in the QF72 incident is VH-QPA, MSN 0553, according to the preliminary accident report (http://www.atsb.gov.au/publications/investigation_reports/2008/AAIR/pdf/AO2008070_interim.pdf).

Also from the ATSB report, the ADIRU's fitted to the aircraft at the time were as follows:
Model name: LTN-101 Global Navigation Air Data Inertial Reference Unit (GNADIRU).
Part Number: 465020-0303-0316.
ADIRU 1 Serial Number 4167
ADIRU 2 Serial Number 4687
ADIRU 3 Serial Number 4663.

Thanks KRviator. Then it does not seem to have changed since then, Part Number still being identical today (April 09), alternate P/N is -0315. Vendor is Northrop Grumman for both.

Unfortunately, the Maintenance Manuals (AMM, IPC, etc.) for A330 MSN550 went offline in the meantime, but for the other recent A330 of AF, MSN 501-510 are fitted with ADIRU by Vendor Honeywell (two different P/N possible). So I expect this to be the case for MSN550 / AF447 as well.

Hence - no obvious interconnection between QF72 and AF447 because of different manufacturers.

[BeechNut]

Will Fraser

How then would you explain that the pressurization ACARS message was the last in the 4 minute sequence, and not the first, or at least, earlier in the sequence? If an explosion breached the hull, ISTM that loss of pressure would have happened well before 4 minutes of time had elapsed.

Beech

[Unusual Attitude]

Not familiar with the Bus so forgive me if this seems a simple question to someone.

Would the Mach Trim have been affected by the loss of the ADIRU, PIRM 1 and SEC 1 etc ? I'm assuming given a loss of Pitot input the systems will have no idea where the aircraft is in relation to MCrit / MMO etc and would therefore not be able to adjust the Mach trim as Mach increases? I'm thinking Mach Tuck as another possibility to the stall / spin scenario?

[Will Fraser]

Not so much here, but I sense a lessening of popular context of the power of a Thunder head, and its potential for disaster.

I mean no disrespect and I don't wish to appear flippant, but if the Fates presented me with the certainty of flight directly through a cell, or a bomb detonating in the hold, I would be tempted to inquire, 'How big a bomb?'

[Phil Space]

I think this map says it all.
http://newsimg.bbc.co.uk/media/images/45858000/gif/_45858989_plane_crash_weather2_466.gif

[Jet A1]

I'm on the A320 so not that clued up on A330 system differences, so if you went into EMER ELEC you would expect the RAT to deploy. If the RAT was to fail/damaged in wx/not deploy - How would that leave you power wise ? Would be down to 30 mins BAT only ?

If you were down to BAT only - that would put you in ALTERNATE LAW.

How quickly on the A330 would the cabin pressure become an issue ? The A320 leaves you with enough time to descend down.

Once the batteries are dead - I presume the ISIS would fail too ?

[Will Fraser]

Beechnut- Good question. I would say, merely to entertain your question, that the position of the explosion and its strength would be important, and also whether ACARS was in real time, or Int. and 'bunched'. (Compressed)

[ttcse]

A number of pages back I stated that charted depictions of ocean currents in that are would have to rule-out currents placing debris to the right, south-east of route. After further reviewing what these charts are and their omission of necessary detail for that area of the ocean, I'd have to retract the previous. It appears entirely possible currents could be a factor but can't say they were. I would think currents would be a factor in why debris locations are so widely displaced. For what its worth.

[DenisG]

@ Phil Space,

is there any confirmation on the accuracy of the map posted by you?

@ everybody

I have two questions I wonder about:

1. The debris has been found in some distance away from the last reported location and in different spots; debris will find no trouble making it that way in 30 hours considering the current (4 km/h), although it is said to have been headed northwest at the time. While debris can spur around quite a bit due to winds etc. the oil/fuselage marks would be much more coherent. Is there any indication that there have been different spots of oil/fuselage being spotted, say 50 km apart or so? If that were the case, it would point to different impacts.

2. As far as I followed this thread and the news, last radio was with INTOL. Would it be possible that an event occurred before the flight came into the storm but after INTOL, possibly disabling any human actions (unconsciousness etc.) and that the plane followed via auto pilot its set path and only then later switched off? Or would there be electronic checks or alarms indicating that?

Thx for your reply and thanks for this great forum.

Regards,

Denis

[mstram]

"I still think people are losing sight of the fact that when transiting the ITCZ, sometimes there is NO ideal way through. You've gotta punch your way somehow and that route depends on what looks better on the radar and outside."

How about the option of turning back and returning to base ?

IMO, that is the root cause of this accident, "press-on-itis", along with possible complacency / over confidence re: extremely severe weather.

Just a coincidence that another AF flight tried to land during a T.S. at CYYZ ?

ASN Aircraft accident Airbus A340-313X F-GLZQ Toronto-Pearson International Airport, ON (YYZ) (http://aviation-safety.net/database/record.php?id=20050802-0)

[etherate]

Just continuing with the weather theory, there have been some interesting posts on Flight International's site regarding AF flights and weather avoidance in the past.

Perhaps some of the long haul drivers may know whether on an ETOPS flight crews may be reluctant to go too far off course avoiding weather to stay within required ETOPS diversion times? Just a thought, if this crew did not in fact deviate around what looks like (from the satellite images posted) a pretty extensive belt of Wx.

[Phil Space]

Despite the wealth of informed comment on this thread trying to pull it together in to a synopsis is difficult.

However the UK Daily Telegraph has this:

Details have emerged of the moments leading up to the disappearance of flight AF 447 with 228 people on-board, with error messages reportedly suggesting the plane was flying too slowly and that two key computers malfunctioned.

Flight data messages provided by an Air France source show the precise chronology of events of flight AF 447 before it plummeted into the sea 400 miles off Brazil on Monday.

These indicate that the pilot reported hitting tropical turbulence at 3am (BST), shortly before reaching Senegalese airspace. It said the plane had passed through tall, dense cumulonimbus thunderclouds.

At this stage, according to a source close to the investigation cited by Le Monde, the Airbus A330-200's speed was "erroneous" - either too fast or too slow. Each plane has an optimal speed when passing through difficult weather conditions, which for unknown reasons, had not been reached by flight AF 447.

Airbus is expected to issue recommendations today to all operators of the A330 model to maintain appropriate thrust levels to steady the plane's flight path in storms.

At 3.10am, the messages show the pilot was presented with a series of major failures over a four-minute period before catastrophe struck, according to automatic data signals cited by the Sao Paulo newspaper, le Jornal da Tarde.

At this time, the automatic pilot was disconnected – either by the pilot or by the plane's inbuilt security system, which flips to manual after detecting a serious error.

It is unclear whether the pilot wanted to manually change course to avoid a dangerous cloud zone – an extremely difficult manoeuvre at such high altitude.

At the same moment, another message indicates that the "fly-by-wire" electronic flight system which controls the wing and tail flaps shifted to "alternative law" – an emergency backup system engaged after multiple electricity failures. This system enables the plane to continue functioning on minimum energy but reduces flight stability. An alarm would have sounded to alert the cabin crew to this.

Two minutes later, another message indicates that two essential computers providing vital information on altitude, speed and flight direction ceased functioning correctly.

Two new messages at 3.13am report electricity breakdowns in the principal and auxiliary flight computers.

At 3.14am, a final message reads "cabin in vertical speed", suggesting a sudden loss of cabin pressure, either the cause or the consequence of the plane breaking up in mid-air.

Despite the precise details, sources close to the investigation contested the chronology and denied that the two computers providing altitude, speed and directional data malfunctioned.

The suggestion that the pilot gradually lost control of the plane appears to counter reports that the plane exploded in mid-air.

These were lent more weight today after a Spanish pilot in the vicinity at the time reported seeing an "intense white flash".

"Suddenly we saw in the distance a strong and intense flash of white light, followed by a downward, vertical trajectory which broke up into six segments," the chief pilot of an Air Comet plane from Lima to Madrid told the Spanish newspaper, El Mundo. He has reported his observations to investigators.

Some experts have supported the theory that the plane exploded, given the wide area where debris has been found.

However, Brazil's defence minister, Nelson Jobim, said an explosion was "improbable" given the 13-mile trail of kerosine spotted on the sea. "If we have fuel slicks, it's because it didn't burn," he said.

Paul-Louis Arslanian, the head of the French air accident bureau in charge of the investigation, also said there were other possible reasons for wide debris area, such as high winds and choppy seas.

Yesterday he warned against hasty "speculation" and said that the search would take time.

Four naval vessels and a tanker are in the area around 400 miles off Brazil's northeastern coast. Some 11 spotter planes are searching for more debris, after finding a seat and a 23-foot metal object thought to be part of the fuselage. A French mini-submarine will arrive in the zone next week.

[Gergely Varju]

Will Fraser: Even if bunched / compressed messages are used, you would send you the already waiting message about cabin pressure with the other messages. So, the order of messages should be considered as relevant factual information.

[PJ2]

From a post by "nyt":
For what it's worth, "Le Monde" claims through a unnamed source
With the exception of a few contributions by those who actually know their stuff and who are recognized as such by others who know their stuff, this statement summarizes the serious shortcomings of this entire thread.

We have "stories" being quoted about speed control, stalling an Airbus, going 'too fast', going 'too slow', getting bombed ad nauseum, with absolutely no basis in fact, "no attribution" as one poster honestly states and no documentation.

All we have are "layman's terms" everywhere, which are not only disrespectful to a general audience but which do great violence to real understanding and comprehension of the airplane, the environment it was operating in and what the crew did and did not do.

We've seen this all before. Decades ago, Randy Sohn on AVSIG very pointedly used to ask the question all the time: "Does anybody actually read the thread?", or are they just interested in hearing the noise of their own voice?

In the eight pages growth while I slept, there is precisely nothing new or even interesting; what I read is manufactured, regurgitated (because someone was too lazy to read the thread - the Vazquez presentation is cited at least five times) or picked out of thin air.

The thread is bulging with explanations to the newly-curious about why in many cases their wild notions about what happened are wrong.

I'm not saying "wait for the report". I'm not that naive and I think informed speculation is a good learning exercise. But for the newbies and others who talk and never listen/read, please - respect what has happened and think before you write. This thread is a deep embarrassment.

[wes_wall]

If one is to lend credence to the reports of the wx experts in lightning using NASA lightning strike data, the storms in the area were not emitting much lightning activity. In fact the closest strike at the time the airplane was in CB area was located some 70 miles away. This being the case, then a strike can all but be discounted, and if true then, it begs the question – what caused the electrical failure alerts?

Once again, I believe the ACARS, which if can be trusted to be fact, are the only few bits of information that have surfaced, and provide a brief insight into what may have occured. Can the dots be connected? They indicate the initial problems which immediately faced the crew.

[Phil Space]

http://www.weathergraphics.com/tim/af447/af447-0215-track.jpg

http://www.weathergraphics.com/tim/af447/af447-0215-zoom.jpg

[CargoOne]

Up to my best knowledge this part of Atlantic is well within ETOPS120, I presume AF and their 330 are ETOPS180 approved? ETOPS180 leaves basically no black spots in Atlantic so whatever en-route deviation is very unlikely to put aircraft outside ETOPS restrictions.

[q100]

Take everything you see in the media regarding aviation in general and this accident in particular with several grains of salt. After all, the media was very quick to make a lot of noise about icing in regard to Colgan 3407...

As a long haul pilot myself, what I want to know is this: Did this flight somehow get itself into WX so extreme that it caused in flight loss of control and/or structural failure? If so, how? And how can the rest of us avoid this happening to ourselves? And, if not WX, what did happen, and how might it be prevented in the future?

50 odd pages of speculation (so far) is not providing an answer to these questions. That will come (hopefully) with time, as this investigation will undoubtedly be difficult and time consuming.

IMHO, these tidbits about QANTAS, Air Comet, Bomb threats to flights from Buenos Aires, etc. are red herrings and useless distractions. What I've heard about the ACARS messages isn't much more helpful and won't be until the actual messages themselves are made public.

Let's all step back a bit and respect the memory of those aboard by refraining from posting "information" that is unverified, or irrelevent, or misleading, etc.

Q.

ps: Those of you are posting relevant, verifiable, germane facts: I thank you.

[Will Fraser]

For obvious reasons, and regrettably, principals in the accident are demonstrating a predictable bent. From the instant "Lightning" (AF) to "incorrect penetration AS", (neither of which are remotely demonstrable at this time) it seems that there is an effort to drop the responsibility anywhere but with the a/c, or the line. Nothing is more apparent than the "massaging" of the public's "opinion". It is disgusting.

[Just wondering]

No Captain is going to go through thunderstorms to stay within a theory based planning stage paperwork excercise calculation.

[Gergely Varju]

Will Fraser: I know well, that it is essential to examine multiple theories, but in this case we not only have an "order of messages", but we also have information about when the messages were received.

And while investigating many possibilities are important the key is, if one theory can't explain some facts, the theory should be adjusted, and if it cannot be adjusted to match the known facts, the theory can be droped.

This is why I think incing, software problems, etc. can be discussed but bombs are unlikely.

Not only because lack of threat, lack of organizations taking responsibility, but also because all the security present at airports, etc.

[M.Mouse]

Well said PJ2, I have never read so much endlessly repeated utter drivel.

Anyone would think that the ITCZ, large and active Cbs and the ability to fly an aeroplane safely were all new!

We don't know what happened and no amount of endless fantasising here will hasten the eventual discovery of what caused the tragedy.

M.Mouse.

(Current widebody longhaul captain)

[Misterredmist]

Just a point about these sequential "ACARS" reports - if the aircraft
was in fact terminally damaged or breaking up, would'nt the computer
systems automatically "report" all sorts of breakdowns, simultaneously,
and yet, these immediate transmission could have been received over
a longer time period by the Paris base due to conditions at the time
and the fact that atmospheric conditions can and do interfere with
such radio transmissions ?

[22 Degree Halo]

The 00:00 UTC rawinsonde report from Fernando de Noronha (http://en.wikipedia.org/wiki/Fernando_de_Noronha), Brazil (below) indicated that the tropical tropopause level was probably located near the 100 hPa pressure level (at a height of 16,649 meters, or 54,623 feet), where the minimum temperature was -77.7º C. The presence of cloud top IR brightness temperatures colder than -80º C on the METEOSAT-9 imagery suggests that many of the strongest thunderstorm updrafts were penetrating the tropopause — and such overshooting thunderstorm updrafts have been known to initiate strong gravity waves aloft that have generated moderate to severe turbulence.


http://cimss.ssec.wisc.edu/goes/blog/wp-content/uploads/2009/06/090601_00Z_SBFN_RAOB.GIF

CIMSS Satellite Blog Blog Archive Air France Flight #447: did weather play a role in the accident? (http://cimss.ssec.wisc.edu/goes/blog/archives/2601)

[DC-ATE]

Just wondering -
No Captain is going to go through thunderstorms to stay within a theory based planning stage paperwork excercise calculation.

You simply do not know that.

[ribt4t]

Just a point about these sequential "ACARS" reports - if the aircraft
was in fact terminally damaged or breaking up, would'nt the computer
systems automatically "report" all sorts of breakdowns, simultaneously,
and yet, these immediate transmission could have been received over
a longer time period by the Paris base due to conditions at the time
and the fact that atmospheric conditions can and do interfere with
such radio transmissions ?

I'm not a pilot but more of a computer / communications person. Wouldn't the reports include a time stamp of when the failure occurred ?

[bbrown1664]

There are a lot of theory's and one of them at least is likely to be correct. One that keeps getting dismissed too quickly is the b word. People keep saying the the Argentina incident a few days before is not linked and therefore not relevant. Is that true? Was the same airframe involved?

Either way nobody knows what happend yet as the CVR and FDR have yet to be located and the wreckage has only just started to be picked up for examination. Lets hope they find the cause of this loss soon to help all of us (and you) understaand if this was just a terrible acccident or something that could have easily been avoided.

[barrymung]

It has been stated that one "expert" said that there could not have been an explosion on board due to unburned patches of kerosine on the sea. Yet eye witness reports from pilots suggest that there was a "bright flash" and around six burning objects falling through the sky, which suggests some sort of explosion.

Either the "expert" is wrong or the pilots who witnessed the event were wrong.

[Frankie_B]

It is my understanding (based on an A320 and an assumption that the A330 architecture is similar) that a loss of one or all ADIRUs does not lead to the failure of the FCC [Flight Control Computers]. If there is no information from the ADIRUs or it is invalid, the FCCs switch to Direct Law. Therefore, it is unclear why PRIM and SEC failures were indicated if ADIRU failed.

The Emergency Electrical Configuration theory also looks sketchy to me. ACARS/SATCOM was operational at the time of the failures, and as far as I know they are supplied through the AC1 bus (which will have to be lost to get to EMER ELEC).

[barrymung]

QUOTE: "There are a lot of theory's and one of them at least is likely to be correct. One that keeps getting dismissed too quickly is the b word."

I personally don't buy into the bomb theory. The possibilty of their being a bomb on board and the plane encountering abnormal adverse weather conditions at the same time is streching things a bit far.

Surely it's far more likely that the weather started a chain of events that brought the plane down?

[bbrown1664]

I personally don't buy into the bomb theory. The possibilty of their being a bomb on board and the plane encountering abnormal adverse weather conditions at the same time is streching things a bit far.

Surely it's far more likely that the weather started a chain of events that brought the plane down?


I like many others agree with this. The questions do remain valid though. Were teh two events linked by the fact that the same airframe was involved?

[Lost in Saigon]

It has been stated that one "expert" said that there could not have been an explosion on board due to unburned patches of kerosine on the sea. Yet eye witness reports from pilots suggest that there was a "bright flash" and around six burning objects falling through the sky, which suggests some sort of explosion.

Either the "expert" is wrong or the pilots who witnessed the event were wrong.


The Pilots were wrong. They were over 2,000km from the AF flight. They probably saw a large meteor. They did not see AF447.

See this post: http://www.pprune.org/4974157-post912.html

[overthewing]

Yet eye witness reports from pilots suggest that there was a "bright flash" and around six burning objects falling through the sky, which suggests some sort of explosion.

A mistranslation, anyway, later corrected to state that the object fell for six seconds.

[TripleBravo]

Either the "expert" is wrong or the pilots who witnessed the event were wrong.
Both are wrong. The "witness" would have been able to see around the earth curvature, as has been stated several times here.

And the "expert" with the kerosene ruling out a fire on board is wrong as well with his conclusion: If he would be an expert, he would know that there are several tanks on board. Burning the one would not automatically imply the others would burn as well. They sure can get to the surface in one piece, breaking there at impact.

I personally do not believe in an on-board fire or explosion as well, but the way of conclusion above is downright wrong.

"Experts" and witnesses... :ugh:

[Danny]

This thread is now closed. The main reason being one of too many uninformed speculators relying on unattributed media quotes which are so far beyond the realms of anything sensible that it just makes the posters look as stupid and ignorant as the media themselves.

I have taken the liberty of quoting a recent post by P2J which emphasises what I am trying to get across. I have highlighted it in a feeble attempt to get those incessant posters who obviously haven't read the whole thread and in particular, those who are relying on sources other than faactual and authoratitive ones.

With the exception of a few contributions by those who actually know their stuff and who are recognized as such by others who know their stuff, this statement summarizes the serious shortcomings of this entire thread.

We have "stories" being quoted about speed control, stalling an Airbus, going 'too fast', going 'too slow', getting bombed ad nauseum, with absolutely no basis in fact, "no attribution" as one poster honestly states and no documentation.

All we have are "layman's terms" everywhere, which are not only disrespectful to a general audience but which do great violence to real understanding and comprehension of the airplane, the environment it was operating in and what the crew did and did not do.

We've seen this all before. Decades ago, Randy Sohn on AVSIG very pointedly used to ask the question all the time: "Does anybody actually read the thread?", or are they just interested in hearing the noise of their own voice?

In the eight pages growth while I slept, there is precisely nothing new or even interesting; what I read is manufactured, regurgitated (because someone was too lazy to read the thread - the Vazquez presentation is cited at least five times) or picked out of thin air.

The thread is bulging with explanations to the newly-curious about why in many cases their wild notions about what happened are wrong.

I'm not saying "wait for the report". I'm not that naive and I think informed speculation is a good learning exercise. But for the newbies and others who talk and never listen/read, please - respect what has happened and think before you write. This thread is a deep embarrassment.

No doubt a new thread will spring to life within minutes of this post. However, be aware that from now on, any posts with content that is considered by the moderators to be based on un-attributed sources or more importantly theories from anyone without a proper understanding of LH, heavy metal flying will be deleted and the poster banned from the thread for future posting. We will decide on who has a realistic understanding of those criteria by reading what is posted and using our own experience as current airline pilots and crew who do LH flying on heavy metal.

If you don't sound right then you will be toast. Hopefully that will lower our workload and stop this incessant theorising by people who only know what they read and hear in the media.

1897 posts of which 947 were deleted!