AF447

[ExSp33db1rd]

Boeing 707. BA911 sideswiped by turbulence around Mt. Fuji.1967.

I believe acident report reckoned that the fin broke off first ?

[Lemurian]

FBW, fair enough, but you have to assume first that you have a lateral moment, or why should it break sideways if the moment is fore and aft ?
Further more, IF we assume only accelerations and not aerodynamic stresses, most of your argument goes down the drain, leaving us to guess at where the structure failed.
Mind you, I would tend to agree with an in-flight break-up and lateral streesses on the vertical fin, I'm just playing the devil's advocate for the sake of prudence.

[Willoz269]

A translated letter from a TransAtlantic pilot:

"My friends....I have a theory re possible causes of the Airbus Air France Crash, and it is based on my own experiences.

The Met phenomenon which happened to me was in the general area of the Air France crash, in May 2001, when I was returning to Spain from Buenos Aires in a B743. From overhead Rio, we followed the exact same route as the Air France Airbus, and passing the area of the accident crossing the Intertropical Front at F370, we found moderate to severe turbulence. For around 1 to 2 minutes of the flight we then experienced a sudden increase of outside air temperature, it went from -48C to -19C.

As a result of this temperature discrepancy, we went from flying with a margin of 10,000Kgs to 15,000kgs outside the flight envelope for that flight level, and the aeroplane started an immediate pitch down, with very strong oscillations. I disconnected the Autopilot and we descended, losing 4,000Ft...we were well in the "Coffin Corner", and I am certain had we not disconnected the Autopilot and regained control of the descent, we might be at the bottom of the Atlantic ourselves, as the Autopilot would have tried to maintain altitude and would not have been possible. I have since been flying an A340 in those routes and have not found the same conditions since, which in my 40 years flying I had never ever considered possible. I would describe it as a massive funnel of 40NM in diameter of incredibly warm air with an embedded CB rising at extremely fast rate...after 5 minutes of flying by the seat of our pants, everything started to get back to normal, temp went back to 048C and I was able to regain climb back to F370.

Airbus advises not to disconnect the Autopilot when entering Turbulence, but a situation like the one I described has not been documented before that I am aware of."

[BigHitDH]

Looking at the pictures posted by PJ2 and the pictures on the brasillian website, it does look like there is a lug attached to some ribbed box structure. The A330 has 3 groups of attachment points for the VS, judging by the relative location, this would appear to be the middle one.

Is anyone able to identify this "box" structure from the photograph?

[ttcse]

Lemurian:Don' put words in my typing : My post was just about too-quick interpretations and conclusions and the remarks I made were another possibilityOk,I'm with you.

so between the posters who see a sideways breakage, and you proposing a far more complicated scenario, where do we stand ?
Not quite so complicated if the aircraft was in a spin when it hit. For a brief moment the VS attach junction had to carry increased forces and after failure that rudder section could've been damaged like that.

Yes, like you I only see a number of possibilities and not so inclined to propose what DID happen.

[The Chaser]

For AB Engineering/training/experienced and knowledgeable people

1. What is the maximum rudder deflection (degrees) available for low speed op's (such as asymmetrics)?
2. What is the limited (NORMAL law) maximum rudder deflection (degrees) available at high altitudes at normal cruise type speeds?
3. Is pedal deflection (when rudder limiter is operational, NORMAL law) designed to be the same foot feel (travel in inches/centimetres) across the entire speed envelope?
4. Is pedal deflection (when rudder limit is 10 degrees, ALTN or DIRECT law) the same foot feel (travel in inches/centimetres) as NORMAL law?

The questions are asked without implication or speculation, rather to understand IF degraded control protections might have an impact on high altitude, high speed upset recovery control inputs verses control surface outputs.


Thankyou

[BigHitDH]

For A330-200, max rudder deflection is 35 deg, A330-300 is 36 deg.

[mickjoebill]

During the tail strike of the A345 in Melbourne in March this year, the flight data recorder was dislodged from its bracket.

There is a picture of the bracket on page 20 of the ATSB report. http://www.atsb.gov.au/publications/investigation_reports/2009/AAIR/pdf/AO2009012_Prelim.pdf

Does Airbus designed FDRs to seperate from the fuselage during a crash?
If so, is this based on a rational that the location beacon works better when the recorder is not surrounded by metal?


Mickjoebill

[Dutch Bru]

I'm puzzled by the "crew rest" part.

http://www.fab.mil.br/portal/voo447/FOTOS/070609/foto_2.JPG

Taking into account the letter "E" in front of CR, I gather that it is a part of the perpendicular side of a mobile rest area the size of an LD6 container. Am I right to suppose that in a 330 this is normally situated just aft of the wings section ?

I couldn't find another 330 example, but here is a LH 340 one to indicate what it should look like:

Photos: Airbus A340-313X Aircraft Pictures | Airliners.net (http://www.airliners.net/photo/Lufthansa/Airbus-A340-313X/0437203/L/&sid=30e0ebd4645b20e037a3ad90ff74cc45)

[Kulwin Park]

Sorry if this has been repeated, but I can only read so much in so little time I have as an engineer ... :}

QUESTION: Does it seem like the fuselage fell out of the sky completely intact, as there is very little wreckage or rubble floating on the surface, only large components/interior parts that have risne from the bottom where a tear is maybe in the fuselage??

Also it may seem to me, that very few bodies have been found (17 I've just heard on the news) due to they were all strapped in during the turbulence. Maybe answering my own question, but it seems that it lost control, entered a vertical profile downward, entered the water like a missile, and reached the sea floor. (not speculating, but I have to investigate the facts all the time to make a correct maintenance decision). The fact that little wreckage is evident is due to probably a pin drop impact, and not a belly-whacker impact seperating aircraft fairings and parts & baggage everywhere. AGREE? Just asking??

Also, from working in the EMS & SAR industry, and searching for bodies myself in the past, it is a known fact that a human body that drowns will sink for the first 3 days, and then rise to the surface after that when the acids reflux and create air bubbles, and bloat the liquid cells under the skin, and cause the body to float. ... Not to grouse you out, but hopefully many more bodies will be recovered in the next few days, as they float, so that families can have closure & bury their loved ones, and be at rest.

Maybe the impact was enough to knock many unconscious, and many have drowned still in their seatbelts. Having investigated and been involved in EMS/SAR roles, I do see that there is little to be found that gives rock evidence, but this little info gives clearer information that it was sudden & quick, not a massive explosion or break-up at all due little recovered parts. The way the vertical fin broke off will give many answers as to the side load forces or G-forces that tore it off.

KP

[lhp]

@Willoz469

According to ACAS, the Auto Pilot off is one of the very first messages. SafetyConcern says, the message doesn't indicate whether it's an automatic or manual switch off. Since it was not preceeded by any other material messages, I think it likely that the autopilot was turned off manually. To me, all the messages that follow are just fallout. The real event happened before 02:10 when the AP went off. And since there wereno failure messages before the AP/off, it wasn't equipment failure that made the pilots turn off the AP. It wasn't a VS breaking off, as the hydraulic failure messages would have preceeded the AP/off message.

[Mad (Flt) Scientist]

@Willoz469

According to ACAS, the Auto Pilot off is one of the very first messages. SafetyConcern says, the message doesn't indicate whether it's an automatic or manual switch off.

I believe someone stated much earlier in the thread that an ACARS message would not post for a manual AP selection. Which makes sense, otherwise every flight would trigger an AP ACARS at end of flight when you get to min use height for the Ap.

I'm trying to find where it was stated (there's a lot of junk here!) but that the AP was not intentionally turned off seems more logical.

[cesarnc]

Numbers of bodies updated to 24... Good for the families and I assume it's good for the investigation as well...

[Dutch Bru]

There is indeed a thin line between the clear objective on the Brazilian side to show that they are up to the salvage job so far out on the ocean and the need to protect the feelings of those who are in mourning.

Indeed the Brazilians are (laudably) going out of their way, and not only in the figurative sense. I read tonight in the Brazilian news a report that 8 more bodies were salvaged (indeed upping the total to 24) by the Brazilian Navy, from what is arguable no longer considered "Brazilian waters" (reportedly halfway to Africa east-north-east of TASIL and over 400 km northeast of St Peter and Paul Rocks)

Chapeau!

[Cloud Cuckooland]

lhp (post #782)
The fault reported in the ACARS message (see page 29)
is "AUTO FLIGHT AP OFF" this is generated by an involuntary disconnect - not manual disconnect. In this case it looks like it was caused by multiple ADR disagree and tripping to ALTN LAW.

Dutch Bru:
The portion wreckage showing the Crew Rest compartment labelling - this is called the LDMCR - Lower Deck Mobile Crew Rest and is just as your LH link photo looks i.e in the forward end of the aft cargo (Hold 4).

Im my airline it is used for cabin crew and one of the pilots if 4 pilots are carried. The Captain, when resting, is always in the other rest closer to the flight deck. Interestingly, EK pilots have previously complained in this forum about the distance of the crew rest from the flight deck in case of emergency - (above door 5 in the B777 and mid cabin EY in the A380) - not sure about their A330's. Other operators generally have the Cockpit crew rest close to the cockpit, however you still have the problem of getting through the security door in a hurry when those inside are too busy/distracted to release it. The only airliner I know of that has the optimal crew rest location (bunk room inside the cockpit) is the B744.

[Nakata77]

the tail fin concerns me. it looks like a fatigue fracture across the base of the tail - a perfectly shear split in a perfect line. that is very strange. if the tail fin broke off because of overload then the aircraft would enter a horiztonal spin hence the pitot tubes seeing differing speed indications and eventually the aircraft will throw itself apart. The g forces on the pilots at the front would have been too great to even do anything

[Diamond Bob]

I've been suspect of the A300 and by extension the A330 (though I honestly don't know how much different they are), since I saw these photos of the AA587 VS. I just can't imagine a metal attachment point breaking like these composite lugs did.

http://home.comcast.net/%7Edonjwinters/AA2.jpg

http://home.comcast.net/%7Edonjwinters/AA3.jpg

[Chicago567]

According to Crain's Chicago Business last week, United Airlines has asked Boeing and the makers of Airbus for competing bids for up to 150 planes, a sales contract worth US $10-$12 billion dollars. Whether AF 447 went down because of a relatively inexpensive Pitot problem v. a massive problem with the tail fin/rudder design or something equally challenging may impact United's choice.

I used to work for the NHTSA investigating fatal truck and car accidents. The process for aircraft is the same: one uses the scientific method and sets up competing hypotheses that explain ALL of the existing scenarios, and then rigorously DISPROVES these hypotheses one by one with ALL existing factual data (even the LAV message will be investigated). The last hypothesis that cannot be disproved is most likely to be correct. The Pentagon already followed this process, presumably based on the ACARS messages, when they said a bomb did not bring down the plane.

I wonder why the Pitot icing is already the most likely explanation with so few data. The NTSB, I believe, would have raised the issue, but would have gathered more data before they disproved all other competing hypotheses. In my experience with mechanical systems and autopses, the evidence from the a/c remains and bodies will be equally valuable as the FDR (which may have been filtered) and the VDR.

[Mad (Flt) Scientist]

This may provide a clue as to what broke first.

No it won't. Because it seems most likely that the TCAS was reporting a fault due to erroneous airspeed or altitude data - just like half the systems on the aircraft at that point. (Exaggeration, but you get the idea)

It's already been pointed out that 23 of 24 (at least) ACARS messages share a potential common cause in air data sources. It would be dangerous to assume an independent cause for one of those messages at this point.

[edmundronald]

Here is a nice link about the AA587 crash details and the controversy about composites (http://www.rvs.uni-bielefeld.de/publications/Reports/CrashOfAA587.pdf). As an engineer, I like the writing style.

[Mad (Flt) Scientist]

Would one of the many people taking the idea of a TCAS Antenna fault and running with that idea please provide validation of that interpretation of the reported ACARS line referring to TCAS, i.e.

34 43/06 WRN WN0906010210 344300506 NAV TCAS FAULT 09-06-01 AF 447

Since I've seen a number of statements that this is not an antenna specific fault, and is entirely consistent with a faulty/erroneous/unreliable air data input. (Including one reference to a QRH procedure (http://www.pprune.org/rumours-news/376433-af447-3.html#post4975455))

[bobrun]

Wasn't there more failures than those related to the air data?

Loss of pitot tubes or ADRs wouldn't explained the failures of PRIM1 and SEC1 flight control computers. It wouldn't cause the aircraft to lose pressure either.

Also, the failures were reported by the CMS computer over 2-3 mins, but that doesn't mean they happened over that period of time.

[Mad (Flt) Scientist]

Wasn't there more failures than those related to the air data?

Loss of pitot tubes or ADRs wouldn't explained the failures of PRIM1 and SEC1 flight control computers. It wouldn't cause the aircraft to lose pressure either.

Also, the failures were reported by the CMS computer over 2-3 mins, but that doesn't mean they happened over that period of time.

The search function is a wonderful thing. link (http://www.pprune.org/rumours-news/376433-af447-35.html#post4983320)

From a pilot prospective and arguably by just looking at the failures on the list:

2- One ADR failure is NOT consistant with flags on PFDs. (airbus eliminates 1 erroneous data source if 2 others are the same, transparently to the pilots)
BUT
Two ADR failures is ! and the ECAM message would read:

3- NAV ADR DISAGREE ! which we find in the list.

4- which in turns get the Airbus to revert to ALT LAW without protections (overspeed, and alpha)

5- autopilots, ATHR, NAV TCAS and F/CTL RUDDER TRVL LIM are associated inop items.

6- F/CTL computers (Prim 1 and SEC 1) could then be reset, and recovered (or not) (they receive wrong data from ADRs)

We're left with the STBY probe, feeding directly (no ADR) the ISIS (self contained stby instrument). Which also seems to report faulty info !!

Near Max rec ceiling, the operational airspeed margin on a jet is quite narrow. easy to go to overspeed, or a stall (no protection), especially in very turbulent conditions.
Flight manually assured using good old techniques of "Pitch and Power", in the QRH for "unreliable airspeed"

7- last message on list : ADVISORY pertaining to Air cond/pressurisation MODE Fault, seems to be linked to cab descent rate (unable to cope with a high VS descent to maintain required DIFF pressure !)

The F/CTL computers will report faults if they get enough bad air data info. The only message which doesn't seem to be directly air data driven is the last one - which may be a result of the aircraft having at that stage departed controlled flight. Or could yet be a strange air data driven one, if the cabin pressure controller is being confused by very strange air data.

And someone familiar with ACARS has mentioned that it takes the system fractions of a second to process a message and transmit it, so we can be reasonably sure that the timings are ROUGHLY correct, at least in terms of the to-the-miute timings.

[ChrisVJ]

I declare my amateur status, just another seeker after information.

I would think, in view of the importance of Pitot tubes, that they should be at least of different types so that a common failure did not cause them all to fail at the same time.

Are all the computers packed in the same bay/compartment? If so does not sound too redundant. (I do understand the electronically redundant thing, but physically safe? Chance in a million means sooner or later it will happens, at least that is my philosophy.)

That distance from land would they typically be using VHF or HF? (re HF aerial in vert. stabiliser.)

I understand three pitot tubes and three ADIRUs. Do A330s also have a steam ASI? If not I can imagine that all three pitot failure would be very difficult at high altitude, turbulence, even moderate, and in the dark.

Is/are AoA indicators part of the pitot tubes?

Are the Pitots electronic, ie, are there sensors in the pitot heads or are there still air pressure tubes back to the ADIRUs. Are the static heads duplicated for each pitot head, do alternate static cut in automatically, by electric switch or (like mine) by pulling a plug/ turning an air cock? (Or am I being naive assuming there is alternate static?)

[Willoz269]

LHP

I think you missed the whole point of the story....it is NOT the autopilot, it is the weather phenomenon that we were trying to highlight!

This guy nearly lost the aeroplane on manual, and the Boeing autopilot would have, in his opinion, led to a crash had he not disengaged. He counts himself as very fortunate to have come out of it alive. He questions if AF447 found a similar or more severe upset and didnt make it out alive.

[Captain-Crunch]

Christy Christy Christy,

Wikipedia is not a source either. If you re-read my post slowly again, you will find that I said it is a summary, and that it is constantly changing.

The ACARS list you keep putting up has errors in it. It is an older version of the new list updated by poster "selfin", a regular poster here who was kind enough to take the time and hand-type the leg report. He has updated it several times. We have communicated by email. If you want to put something up, please go to the trouble to get the lastest information. It is here:

http://www.pprune.org/4975386-post42.html

Now I'm sure you're a great pilot in your own right. But that doesn't make you an expert in Accident investigation. I witnessed your vindictive aggressiveness on the 123-Go Airlines thread, and I must say I thought it was detrimental to air safety as all you accomplished over there was to start a which hunt and put the poor slob out of business (as opposed to working with him to fix the problems.) You appear to have a sensationalist agenda. Most of the posters here are not out to smear Airbus or Air France. We understand that Aviation is a challenging endeavor for both employees and owners. We are just trying to get as many EDUCATED inputs as possible.

My hat is off, however, to the French Pilot's Union for taking a stand on defective pitot tubes and refusing to fly. :ok:

:D :D :D :D :D :D :D :D :D

CC

[Captain-Crunch]

Kulwin Park,

It's possible the airplane didn't hit the water intact. But so far, from the scraps of clues we have (lack of a red cab alt warn, tight debris dispersal pattern if that is the case), tends to discount the likelihood that it came apart at hight altitude.

Because of the ACARS transmission requirements and characteristics and need for normal ships power, I feel it's safe to say that the airframe was intact at the time of the last transmission 0214z. Whether that Amber ECAM Advisory was a Cab decent advisory, or, an amber "Excessive Cabin V/S" has not been answered yet completely to my satisfaction by the techs here and other places in an affirmative fashion. They suspect that that's what it is; but the jury is still out even when they are referencing the 330 TSM and AMM's. It's not a red warning however imho.

Again, I don't see any acars evidence that a complete loss of cabin pressure occured prior to 0214z. (Maybe later in the dive at breakup.) But there is evidence of a severe loss of full flight control protections at 0213z caused most likely by loss of Air Data Computer function caused by loss of pitot air sensor data a few minutes earlier. (caused by, if previous airbus accidents reports are any guide: probe icing.)

Disclaimer: I have not flown the A330 and am unfamiliar with FBW.
But considering their wx and weight, a loss of control (jet upset) seems likely. Once you dive tens of thousands of feet in the dark like Adam Air did, high G's in the pull up are going to guarantee that things start coming off the airplane, (Cowlings and Fairing are the first to leave: we had two crews do this) likely followed by major structural damage of the forward and aft main spars in the wings and horizontal stabilizer. If you lose the rudder, then you're in bad trouble. But if you lose the vertical stabilizer (as was floating in the water), the game is completely over. I have examined airliners (as just a line pilot) after evasive flight control deflections, and the counter weights come off the control horns of elevators and large sections at the tips break off (if the stab is designed properly).

Some flyers brought the subject back up of Dutch roll at altitude. Unfortunately, airbus training that I've been in, doesn't demonstrate how to counter the effects of dutch roll if all yaw damper function is lost (the: that's never going to happen mentality). If line pilots try to use the rudder to right the aircraft, they will loose control even if all the flight controls are working properly. The correct way to keep flying at altitude is so tricky with the roll spoilers only (opposing every roll motion AFTER the roll is at it's zenith), that you are strongly advised to slow down and descend to a lower altitude immediately, like say FL290. This is sadly, going to put you is the bad weather were you don't want to be. But if you don't do it, I'm afraid not even old Mr. Neil Armstrong could save this one. Maybe at Edwards on a nice day, but not in the dark, in a storm with failing flight controls and failing instruments at the same time.

If all yaw damp function was lost, this would have quickly become a compound emergency that 90% of line pilots could not control even if they were "sticks".

My experience with rudder limiters is that it is expected that it will fail in its present mode. For example, if it fails at FL350, in high speed/low travel mode, you will loose rudder travel capability at low/slow altitude. If it fails in low speed mode, and now you're indicating fast, you could break the tail off with even normal rudder inputs. The problem is, with AF447, nobody knows at 350 in cruise what mode it failed in with the airspeed all over the place.

Right?

CC

The above, as all my posts are, are just my opinions only.

[Mad (Flt) Scientist]

I declare my amateur status, just another seeker after information.

I would think, in view of the importance of Pitot tubes, that they should be at least of different types so that a common failure did not cause them all to fail at the same time.

Dissimilar components cause as many problems though. If you want to rely on being able to compare the outputs, then the components have to be practically identical. In particular, you're forced to design to at least the same specification, and perhaps the actual same design details (in the case of a pitot probe, geometry for example). So the same extreme conditions which will disable probe A will quite likely also disable probes B and c anyway. meanwhile you have to deal with the nuisance of 2 or 3 suppliers for one part, carrying more spare parts in the maintenance pool, and so on.

This may well not be common failure - in the sense of the probes being at fault - it may be the case that the environment was too much for them.

Suppose you wish to drive your car quickly, and put high speed-rated tyres on all 4 wheels, but to "be safe" you go for one Michelin, one Goodyear, one Bridgestone and one (someone else). Then you drive at 20mph over the rated limit for all the tyres anyway. The fact that they are dissimilar sourced won't do much good, in all likelihood. You're pushing them all outside their design spec anyway.

I understand three pitot tubes and three ADIRUs. Do A330s also have a steam ASI? If not I can imagine that all three pitot failure would be very difficult at high altitude, turbulence, even moderate, and in the dark.

ISIS is the "integrated standby" for when the main three systems fail - but it still has to source pressure from outside, so again, the environment could well be the issue. Not the aircraft components.

Is/are AoA indicators part of the pitot tubes?
No, different component. Some a/c use measured AoA to correct the measured air data - I don't know if this is the case for A330 or not.

Are the Pitots electronic, ie, are there sensors in the pitot heads or are there still air pressure tubes back to the ADIRUs. Are the static heads duplicated for each pitot head, do alternate static cut in automatically, by electric switch or (like mine) by pulling a plug/ turning an air cock? (Or am I being naive assuming there is alternate static?)

Air pressure lines to the ADIRUs, I believe. Most large a/c will have duplicate (left/right) statics for each pitot, to balance sideslip effects; again, I expect that to be the case here. The back-ups are through the multiple ADIRUs and ISIS - I doubt the crew can reconfigure the system beyond selecting which ADIRU they can display data from.

I'll remove my speculative statements if/when someone more knowledgable comes along

[Captain-Crunch]

ChristySweet:
You then wrote; 1 ) asking for any proof of a " turbulence encountered " message, again the link I provide has the list of received messages -and sure enough , there is NOT a" turbulance encountered" message. ( Voice, ACARS or keyboard..)


I don't think so. A message about turbulence is NOT going to be sent on that list to maintenance. Don't you understand this? Those are all AUTOMATED messages sent within miliseconds of the computer detecting the comparator disparities to the MECHANICS. :eek:

A human hand on the keyboard is likely to send a turbulence report to????????
Flight Operations! Assuming he pushed the right ACARS MESSAGE DEST button in turb! :E

CC

[philpop]

CC,

In this scenario, how would you explain that radio was not used for MAYDAY

[bobrun]

The F/CTL computers will report faults if they get enough bad air data info

Been through the FCOM3, and no where does it indicates that an ADR failure (or all of them for that matter) would fail the PRIMs or SECs?

They do receive information from they ADRs, but as the the fault was recognised by the PRIM, (the ADR DISAGREE fault was announced, indicating only two ADR were being used by the PRIMs and these ADR disagreed), ALT LAW would be latch and it would appear to be the end of it. Would you care to explain a bit more?

[Lightning6]

CC,

In this scenario, how would you explain that radio was not used for MAYDAY

Aviate

Navigate

Communicate

Are the priorities.

[lomapaseo]

grizzled

I didn't get the impression that either dani's post or lomapaseo's were referring directly to you or your posts. In dani's case he wasn't at all swatting at flies; he was making (what I thought at least) was an accurate and appropriate comment re some of the speculation of the past day. It seems to me that Lompaseo was doing the same thing.

Grizzled

Thanks for that.

Typically if I intend to counter a single post idea I will quote it. If I intend to offer a rebuttal directly to a person's individual opinion then I will include their name to avoid any other attribution.

PJ2 posts are quite capable of standing on their own and eloquently expressed. I might be adding my own tint of color from time to time on the subject just to broaden the readers outlook :)

[marchino61]

All my posts regarding a theory where an exploding oxy bottle (located in the avionics compartment, where all the computers are located, and very near all the probes as well) would be the root cause of the accident (QF had an oxy bottle explode a few months ago, resulting in a huge hole in the fuselage) have been deleted!! Even the post where I ask what happened with my previous posts has been removed.

Is this thread being censored?

Yes. Posts which speculate on causes not backed up by the facts are being deleted by the moderators, I believe.

There is no reason to suppose any such explosion. There was no explosive decompression indicated.

[Captain-Crunch]

CC,

In this scenario, how would you explain that radio was not used for MAYDAY

Good Question Philpop,

Since you asked respectfully, unlike Christy, I'll answer.

It takes a good number of seconds via any means to get a message off, no matter is it's HF, (high freq), ACARs (even longer) or even VHF on guard.

If the chit hits the fan, and you start fooling around looking for your hand-mike, screaming for people thousands of miles away to help you, then you will die. This wasn't a small thing that happened (Full Pinball TILT). The automation went haywire. The train came off the track. If you start spinning sideways in your car and decide right then, that you need to call for help on your CB..... guess what? Better hope that Channel 16 is the Coroner!

The first thing you must do, at all costs, is Hand Fly the Machine, while the other guy (let's hope he wasn't in the head) gets the train back on the track by restoring Air Data that the autopilot will accept. If you waste even a few seconds scratching your head at 500mph, it's adios controlled flight!

But these poor guys had 3-4 minutes of shear terror to deal with. And it's clear they never got back under control.

Aviate (get it under control, using hand flying and partial panel skills not taught anymore)

Navigate (radar cell avoidance)

and lastly, if you don't have enough to do already with the HAL-9000 going "DingDingDingDingDing"

Communicate.

CC

(see? It's not the Bermuda Triangle out there. It's over-reliance on automation imho.)

[Mad (Flt) Scientist]

Been through the FCOM3, and no where does it indicates that an ADR failure (or all of them for that matter) would fail the PRIMs or SECs?

They do receive information from they ADRs, but as the the fault was recognised by the PRIM, (the ADR DISAGREE fault was announced, indicating only two ADR were being used by the PRIMs and these ADR disagreed), ALT LAW would be latch and it would appear to be the end of it. Would you care to explain a bit more?

Perhaps the IR2 FLR immediately before the two F/CTL warnings in the ACARS list?

[Wytnucls]

No ACARS messages were received after 0214, suggesting a catastrophic airframe failure shortly thereafter. The vertical stabilizer probably sheared off then, either causing the loss of control and break-up, or, more likely, as a consequence of detrimental airloads during departure from normal flight.

[Graybeard]

Airspeed calculation and indication depends on valid altitude calculation. Altitude calculation does not need airspeed, except for fine trimming. If icing the pitot tubes clogged them up, there is no logical reason to kill their companion static data outputs, as appears to have happened with this plane. It would seem to take a lot more icing to clog the static ports at the same time.

The Air Data boxes must have condemned the validity of their altitude outputs as well as airspeed, or the TCAS would not have flagged failed. TCAS does not have an airspeed input. Hence, if the "Pitot tubes are defective" is true, the Air Data boxes are also lacking necessary partitioning in their outputs.

By design, faulty airspeed computation/indication should not affect altitude computation/indication.

If clogged pitot were a not so rare phenomenon, altitude, attitude and ground speed would be used to simulate airspeed, using the last valid airspeed as baseline. But more than one pitot failing at a time is "too rare to consider."

GB

[FE Hoppy]

Just because they have found the fin doesn't make it the prime suspect. There is nothing that indicates when it detached and very little to suggest why.
The speculators are out in force today. We had hot air bubbles 2 days ago and it's airbus composit material failure today. If they find an engine next are we going to blame that?

[spacesage]

FEHOppy,

You should actually read what I posted, I suggested that the state of the vertical stabiliser was the evidence, it did not appear to have been subjected to the extremely destructive forces of impact, suggesting it seperated in flight.

The radar system they are using to discover these components is a very sensitive one. Visual range of the MK1 eyeball is very limited. These large pieces are most likely being discovered by radar. This suggests that is is unlikely they will find anything larger. I know these facts from my experience as a naval air controller, none of it is speculation.

If you wish to make non-constructive comments and wait for the final report I suggest you don't post.

[Wytnucls]

The fact is, we know from previous experience and from Airbus admission that the fin is very sensitive to excessive sideloads.
In very extreme turbulence or in a loss of control situation, it is not unreasonable to expect such high loads on the vertical stabilizer.
It will be important to find out if the possible loss of the fin at altitude contributed to the accident or not.
Of course it could have remained attached until the airframe plunged in the water, but I find that option less likely. Time will tell.

[Capn Bloggs]

In this scenario, how would you explain that radio was not used for MAYDAY
Human nature is at play here also. Whether it be as CC said, crew working too hard to make a call, or mind closing down by the reality of imminent death, I don't know, but aircraft have crashed with what seemed like ample time for the crew to holler something on the radio, but they did not. There's been grunts and groans on CVRs, but not much on the radio.

[Safety Concerns]

ACARS only transmits what it is told. It has no influence on any warning messages at all and acars does not time stamp them.

CFDS sends messages to ACARS for transmitting. CFDS also logs any ECAM warning without filtering. So for the real pilots out there can you now answer the following questions:

I have just tripped the A330 autopilot manually to off. Do I get a warning?
If yes acars will transmit it, if no acars cant transmit nothing?

Hopefully that has cleared up that one.

[vapilot2004]

Would the yaw damper remain operational following the air data disagreements?

IOW -- would it auto-disengage along with the AP and the downgrade to Alternate Law?

@Zeffy - there are reversion modes even in Alternate law where some yaw damping functions are retained. Also, even with a loss of ATT data from the ADIRUs, there are dedicated gyros to assist with yaw control on the A330.

[vapilot2004]

@Safety Concerns:

I had earlier wondered the same thing when deciphering the ACARS messages and had been told (by an amused old fellow) and posted my answer earlier: An autopilot being switched off in the cockpit is nothing the Airbus CMS (Boeing acronym, sorry) will report home about.

To make it even clearer, logging and reporting to home base are two different functions and I have been told the choices of maintenance data sent can be airline-specific customizations.

[Dutch Bru]

A remarkable website of BEA, the French bureau of investigation and analysis for the safety of civil aviation.
No sign of a report on the alleged collision of F-GZCP with another airbus in late 2006, but they do have a report on a similar incident in 2002 between two Italian Airbuses 330 clipping each others wings on French territory. Mmm….
Anyhow, I came across another interesting BEA publication from August 2008, a fully fledged study on “turbulence and air transport”. In French only of course, but never mind. For those who like me want to have go at it, here is the link:
[URL="http://www.bea.aero/etudes/turbulences.en.transport.aerien/turbulences.en.transport.aerien.pdf"]http://www.bea.aero/etudes/turbulences.en.transport.aerien/turbulences.en.transport.aerien.pdf URL]
The 34 pages of the report give a fresh reminder of the treacherous aspects of convective cells naturally also covered in the current pprune thread. The report takes 48 occurrences between 1995 and 2007 with French registered, exploited or produced aircraft in France or abroad as a basis for study. Much more than half of the accidents and incidents have occurred in or next to Cumulonimbus, in which circumstances also the most seriously wounded were registered.
Despite a good flight preparation which includes in many cases an awareness of adverse weather conditions en route, it is stated that many pilots are nonetheless very surprised when they are actually confronted with turbulence. In particular for long distance flights the report points to the aids available to flight crews to stay alert and informed about actual and developing weather conditions en route. The on board weather radar is mentioned in terms of its vital importance, but also the challenges and even shortcomings of its optimal use. And more interesting and useful stuff.One final thing I would like to highlight has to do with the recurrent discussions in this thread about the supposed message that the AF 447 crew sent by ACARS to inform their company that they were experiencing severe turbulence. The report mentions explicitly that some French airline companies, in particular those that fly long distance routes, have dedicated departments that communicate via ACARS on updated weather situations en route. Where those departments are then specifically tasked with providing specific updates on weather to flightcrews. I would be surprised if AF would not have such a dedicated department. In that light an ACARS based exchange sounds very plausible. One of the questions in the AF447 case would then be why it was the pilot informing the dedicated department of the severe weather when they were experiencing it, and not the other way around so that avoiding action could have been taken.

[nyt]

Wytnucls, you mean that it's not overbuilt ? Not surprising since it "only" needs to be up to spec.. I don't get your point.

[LUALBA]

FYI.

Please, be patient.

At this stage of the investigation, there are no new available data
than the messages which have been transmitted automatically from the
aircraft to the airline maintenance center.

The above mentioned messages indicate that there was unreliable
airspeed indication. This unreliable airspeed situation is consolidated
by several messages which show system reconfigurations which are per-
design consequences of the unreliable airspeed indication.

The last transmitted message corresponds to the ECAM Advisory message
indicating a change of cabin altitude at a rate greater than 1800
ft/min, which remains to be explained.

Some messages might be consistent with unreliable airspeed indication
but require further analysis. Other messages likely result from further
aircraft evolution and/or crew actions. Finally system status messages
have also been transmitted but are not relevant for the understanding
of the event.

The data available at this stage of the investigation:
- does not suggest any loss of electrical power supply,
- does not suggest a loss of instrument display,
- does not suggest an ADIRU misbehaviour as encountered in a recent
A330 event for 2 reasons: the ADIRU supplier and the signature of
failure related messages are not the same as on AF447,
- does not explain the complete sequence of events which led to
AF447 accident.

Airbus continues to provide the full technical support to the BEA in
the frame of the on-going ICAO Annex 13 investigation.

Airbus also provides support to EASA (European Aviation Safety Agency)
to assess if there will be the need or not for further precautionary
steps. Airbus will inform operators should either Airbus and/or
Investigation Board and/or Airworthiness Authorities determine the need
for further precautionary measures

Regarding the pitot tube, the fleet is currently fitted with 3
different standards: 2 from Thales supplier (std -AA and -BA, AF447
standard was -AA) and one standard from Goodrich. Concerning the Thales
standard, the latest -BA standard has been developed to enhance water
drainage encountered during heavy rain conditions on take-off or
landing phases.

Pending further investigation inputs, Airbus confirms at this stage
that the fleet in its various pitot tube standards can continue
operations and take the opportunity to recommend operators to remind
their pilots on the applicable and existing operational procedures as
recalled in the AIT n°2.

Airbus understands the need to share accident data with operators in a
prevention objective, while complying with communication requirements
set by the Official Investigation Board. This is why update on the
accident data will be provided as soon as further valuable information
is available and approved for release by the Investigation Board.

[worrab]

Given that no-one has yet indicated where the VS was found, isn't it a bit early to be deciding whether it was cause or effect? If the VS came off at altitude and "floats like a leaf" through the air then it would in all likelihood have been some distance from the main debris field and the Brazillians (who appear to be doing an excellent job) would have had one heck of a job to find it. If (as seems likely) it WAS with the main field then it may have still been attached to the airframe even - depending on attitude - at beyond the point of impact.
It isn't possible to make an infinitely strong aircraft. If sufficient forces apply, something will break, but at this stage we really don't know whether the strong force was aerodynamic or hydrodynamic.

[deSitter]

This is naive. We have on the record another case of turbulent air leading to the pilot-induced loss of the vertical stabilizer and then the whole airplane, under perhaps more forgiving conditions. The problem was in the composites themselves. Before, I think it was always assumed that a pilot could not tear up his airplane just by trying to fly it.

-drl

[Junkers388L]

SafetyConcerns, you asked:


I have just tripped the A330 autopilot manually to off. Do I get a warning?
If yes acars will transmit it, if no acars cant transmit nothing?



On the A320 (and A330/340 will be idem), you will always get

- a flashing MASTER WARNING light
- a red message on the ECAM
- an audio alert (cavalry charge)

irrespective of whether you disengage the autopilot manually or not.

If you disconnect the AP in the nominal way, i.e. via the TAKE OVER PB on the side stick, the warnings are temporary, of shorter minimum duration and can be completely cleared e.g. by a 2nd push on the TAKE OVER PB. On the ECAM, you will get a simple "AP OFF", and no ECAM status message.

In any other case, irrespective of whether the AP disengagement results from other crew action (such as sidestick deflection beyond a certain limit, or using the AP pushbuttons on the FCU for a disconnect) or a failure/exceeded engagement conditions, warnings will be continuous and you will get "AUTO FLIGHT AP OFF" on the ECAM and a status message.

Hope I got that sufficiently correct and clear ;-)

I would suspect that transmitting the manual AP off condition via ACARS is one of the myriad customer options.

[worrab]

If it's naive to be prepared to consider all the evidence before leaping to a conclusion then I accept your criticism.

There is a coherent, plausible chain of events presented in this thread which could explain the entire, sad incident - bad weather, iced pitot tubes, nasty temperature changes leading to a critical need for accurate speed control, perhaps insufficient thrust to overcome problems followed by aerodynamic breakup of the VS. Very neat, very tidy. Someone tell the BEA and we can all pack up and go home. One of the challenges of forensic endeavour is to keep an open mind until the evidence can be seen as a whole. I agree that pitots have become blocked/iced in the past and that there appears to have been a pitot problem, I concur that that would make flying this aircraft in these conditions very difficult and perhaps impossible. The loss of the VS would likely/certainly be terminal and a VS has failed in the past because of excessive aerdynamic force. It may have become detatched at altitude.

Some or all of the above may have contributed to this tragedy but I, for one, am still prepared to wait for the evidence.

[kwachon]

From the pictures released so far, I see a only section of vertical stab, I do not see a rudder!, The CVR and FDR are not located in the VS, go to smart cockpit.com and look up the A330, there you will find a layout of where things are placed within the fuselage. Lets keep things real here and based on facts as they are known thus far.

KW

[Hotel Mode]

I see a only section of vertical stab, I do not see a rudder!,

Take a look at a decent picture of an AF A330. Compare the location of the european stars with the rear of the fin. The bottom of the stars are level with the top of the 3rd blue stripe, exactly as in the photo. The Rudder is still there, its just not visible at the resolution of the photo.

[Wytnucls]

Fact: Most of the red stripe is painted on the rudder section.

[lhr_syd]

It seems most observers are following the pitot malfunction as a precursor to other events (including AB/AF amongst others suggesting a change pitot remedy).

Some posts back (or is it in the closed thread?) there was an erudite suggestion that a spiralling aircraft would give rise to erroneous readings from the pitots. That post suggested VS separation or some other catastrophic event as higher in the event chain.

I have not seen an argument supporting or contradicting that post. Most have followed the 'pitot first' event chain.

[Wytnucls]

That's because the 'pitot first' theory is best supported by the flurry of ACARS messages over a 4 minute period.
The total loss of ADR data is survivable, if handled correctly by the crew, so there may have been more hardship faced by the pilots before they lost control of the aeroplane. Severe turbulence and structural failure comes to mind.
Some strange ACARS messages have not been fully explained yet, like the line about the 'IR2' and the failure of PRIM1 and SEC1.

[BOAC]

It is time to dig out the old, cracked vinyl record and say "PLEASE WAIT FOR FACTS"

ASSUMING 'pan gloss's' first post (this am) stays here I recommend everyone reads the first, second and last paragraphs. My feelings entirely. Just in case it is whisked away I copy here those paragraphs. (EDIT: Too late - it has gone:ugh:)

Keep the good analytical work (and leave the speculation behind)
So far, I have kept quiet on this subject, as I think that many of you provided a great and thorough analysis on the few available facts (e.g. the ACARS messages). I truly dislike all the true speculation, because it clutters up this thread without adding any value.

It would probably be useful to create a new topic which summarizes the thorough analysis performed early in this second thread, as even the Wikipedia summary keeps getting messed up. And this one here is already a true pain to read.

........

One question I have not found anything related to - despite following both threads closely: Do the AF447 messages truly end on top of page 39 of the ACARS summary or were there possibly further messages which were not broadcasted by TF2? Statistically there is quite a small likelihood (e.g. 7.14%) that the last message coincides exactly with a page break (in this case the top of page 29 of 256, as the header indicates).
------------------------------------

Guys and girls, the dogs are again out chasing the hares. We have a grainy picture of a floating fin assembly. Speculation is rife as to what happened to it. We can only be hours away now from major new hard information - the metallurgical nature of the fin failure and an idea of both the cause of death of the recovered bodies and their allocated seats.

For some inexplicable reason, the BEST post since fin discovery is now in JB. (http://www.pprune.org/jet-blast/375943-air-france-jet-missing-14.html#post4984522) Again I reproduce the bulk of arcniz's (current post #263) from JB

evidence of skin-bending, surface contamination and dimpling changes, combined with structural deformations of the vertical tail, will likely give fair evidence to the mode and timing of separation from the airframe proper - whether 'twas in the air or on contact with the water, and whether fast or slow and whether stress-loaded in the forward direction of flight or totherwise.

Futhermore, if those fancy ocean-current models are as smart as some says they be, the position where it was found may point to the position where tail and fuselage were last in close proximity.

Most of us involved in aviation turn to THIS thread for facts, not speculation.

[Interflug]

I guess if the public had seen the picture of the VS first and days later the ACARS report, it would be the other way around and the "established" speculation would center around the VS, trying to "fit" the ACARS in.

Nothing against intelligent speculation, without it mankind would still sit in trees and caves. But there are limits and we must wait for more facts.

[pan_gloss]

After my first post (I usually keep quiet) has gone for inexplicable reasons (thanks BOAC for saving part of it), I would like to introduce back some facts into the game, based on earlier messages from rather reliable sources.

First of all, the only half-way reliable information we have are the ACARS messages (of which I am not sure they are complete after 0214, but maybe someone has an answer to that). They indicate (mostly) the following:

- Pitot probes had disagreeing values
- AP disengaged (automatically, a crew switching it off does NOT cause an ACARS message), which is - according to AB manuals a logical consequence of contradicting true air speed input
- There was a cabin pressure warning (yet not indicating anything severe)

A few more (as I know) related facts:
- The plane had normal power at least until 0214 (otherwise there would have been no ACARS message)
- Free fall from 0210-0214 (or anything close to free fall) is impossible, given the laws of physics
- There were (high probability, as we see messages from the previous day) no other ACARS warnings or faults before 0210

That's my 1/2 cent, delete it or not.

[lhr_syd]

"That would reinforce the idea that the plane broke up in flight," he said. "If it hits intact, everything shatters in tiny pieces."

A quote on the Telegraph (http://www.telegraph.co.uk/news/worldnews/southamerica/brazil/5482798/Air-France-crash-Investigators-recover-29-bodies-in-total.html) by William Waldock, who teaches air crash investigation at Embry-Riddle Aeronautical University in Prescott, Arizona.

I was interested in the assertion itself because the VS from the XL A320 (repainted in NZ livery) at the Perpignan incident was pretty intact although the aircraft hit intact.

[Flyguy2006]

I know the facts state that the tail of the Air NZ was more or less intact after impact but wasn't the altitude quite drastically different from the AF?

[Pinkman]

Is the VS attachment point forward or rear of the rear pressure bulkhead i.e. would its separation lead to depressurization (hence the ACARS msg re cabin press?)

[connector]

STEF
JUST FOR INFO
ACARS COST MONEY!
You have to have the organisation to manage it.
Therefore a lot of "minor" Airbus airlines,
dont use it!:rolleyes:

[lhr_syd]

I know the facts state that the tail of the Air NZ was more or less intact after impact but wasn't the altitude quite drastically different from the AF?

Quite so, Flyguy2006.:ok: 3000m (I think!) vs FL350.

[Dysag]

This is an A300, but I doubt the A330 is fundamentally different. It appears to show the first VS attachment point just aft of the pressure bulkhead.

http://www.flightglobal.com/airspace/photos/civilaviation1949-2006cutaways/images/6668/airbus-a300-tail-detail-cutaway.jpg

Furthermore, fwd of the bulkhead there's nothing to attach it to, except the normal fuselage frames.

[flyboy2]

By: Keith Campbell 5th June 2009

source:-

http://www.engineeringnews.co.za/article/following-air-france-tragedy-airbus-issues-precautionary-telex-to-airlines-2009-06-05

Following the tragic loss of Air France Airbus A330-200 F-GZCP, flight AF447 from Rio de Janeiro to Paris, early on Monday morning, the European airliner manufacturer has issued an Air Information Telex (AIT) to airlines. This AIT is a precuationary measure and reminds the airlines of the recommended procedures flight crew should follow when flying an aircraft in weather conditions which are likely to cause rapid changes in airspeed.

The procedures concerned apply to the operation of all jet-powered airliners, and not just Airbus aircraft. They are already in wide use by most airlines and are incorporated in both initial and refresher pilot training courses.

The conditions concerned typically include flying in the vicinity fo storm cells, in wind-shear, in clear-air turbulence, and flying across jetstreams. These phenomena can all subject an aircraft to volumes of air moving in opposite directions and conflcting with each other. This, in turn, can cause rapid changes in the airspeed of an aircraft.

Airbus reports that the automated measures transmitted by F-GZCP immediately before its loss showed an inconsistency in the different measurements of the aircraft's airspeed. The AIT reminds airlines of the recommended procedures to be followed in such a situation, in which the actual airspeed becomes unclear.

Airbus stresses that this AIT must not be seen as a confirmation of the causes of the loss of AF447. The company points out that the investigation into the loss of F-GZCP is still under way. The causes of this divergency in airspeed measurement by F-GZCP's systems are one of the matters being investigated.

It highlights that, as a manufacturer, it has an obligation, in the interests of safety, to remind its customers of certain procedures. The issuing of this AIT was done in agreement with France's Bureau d'Enquêtes et d'Analyses, which is the agency responsible for the investigation into the loss of flight AF447.

Largely unheralded, Airbus had some good news this week, with the maiden flight of the first A330-200 destined to be converted into a strategic air-to-air refuelling tanker for the UK Royal Air Force (RAF). The aircraft was assembled at Airbus' Toulouse plant but will undergo militarisation and tanker conversion at the Airbus Military plant at Getafe, near Madrid. This specialist RAF version of the aircraft is powered by two Rolls-Royce Trent 700 engines, and 14 are on order in a £13-billion ($20,9-billion) deal.

[nsxtasy]

I have read every single page of the first thread and now this one. You can tell there are some very knowledgable pilots and rubbish.

This information below was just posted 7 hours ago and thought it might be of useful information to a few experts here.

Engineer decodes Air France Flight 447 emergency messages (http://blog.seattlepi.com/aerospace/archives/170669.asp?source=mypi)

Part 2 of a pod cast where a Honeywell expert goes thru all ACARS messages sent from AF447:
Innovation Analysis Group (http://www.iag-inc.com/premium/)

There is also Part 1 in which a long haul commercial pilot explains the pre-flight procedures as well as how the flight tracks its route from departure to destination, picking its way through weather.

Keep up the good work!

[Swedish Steve]

looking at the acars message list there is a line with IR2, IR1, IR3, ISIS.

Which line? I can't see it
There is IR2, as reported by EFCS, IR1 IR3
and below it another message ISIS.

[stezam65]

To Swedish Steve:

Steve, I meant those two lines you have seen....

I am a pilot but not a decoder of acars message.
I can understand the ECAM message when I am in the plane but not what Ecam message have been transcript and traduced in the Operational and Maintenance headquarter....
For that reason I sent my question in this forum just for Acars readers expert.

Ciao
Stef

[robharris999]

Apologies if this issue has been raised previously. I am interested to know if excessive rudder deflection as a result innacurate speed sensing affecting rudder limiters would cause damage just to the rudder or the complete VS. Can anyone enlighten me?

[nsxtasy]

In regards to the ACARS messages has anyone had a chance to preview this link?

Innovation Analysis Group (http://www.iag-inc.com/premium/)

A Honeywell expert goes thru the list of AF447 ACARS messages and tells viewers what has likely happened.

[Swedish Steve]

stef, sorry.
The Warnings as seen by the pilot on ECAM would be IR2.
The rest of the line is the reporting computors.
If you get a warning in flight, produce a PFR when you have shut down. You can then see the original warning, and the reporters. Also in the maint section will be the code generated.

The ACARS sheet you posted contains all this in one line. makes it hard to interpret if you don't see it that way usually, and you never will on the aircraft.

[Swedish Steve]

I have a question.

As a mere engineer, I understand the problems of high altitude flight with the proximity of stall speed and overspeed.

With the known problems of pitot icing (though I have never seen it) why don't you pilots just stop flying so high when there are storms about? Would it not be easy to mandate a descent to a lower FL where the speed range is greater so you have more time to react if something goes wrong?

Yes I know it costs money, but so do crashes.

[oldshuck]

Re the VS and rudder question if you Google F-GZCP there is a good picture of the actual aircraft that will show relationship of rudder to VS

[MLT]

The purpose of a Rudder Travel Limiter is exactly that. As airspeed increases (computed by the air data system) the amount of rudder travel permitted is limited. This prevents excessive loading on the tail structure at high speeds.

If the Rudder Travel Limiting system were to fail, then the travel should be limited at it's last setting eg. if it failed at high speed it would limit to the high speed setting until slats were selected to 'out'.

If the system were to receive incorrect airspeed through the air data system however (due to probe icing??) the rudder travel limiter may be set to allow more travel due to the incorrect computed airspeed vs the actual airspeed. This could mean that the vertical stabilizer might receive excessive structural loading.

MLT

[HarryMann]

robharris

It is not so much the rudder deflection itself as the resulting yaw from that rudder input that would be the issue. The limitation on rudder travel is not so much to limit rudder loads as yaw, which produces all sorts of secondary aerodynamic and structural loading effetcs, ONE of which would be high bending and shear loads on the fin attachment to the fuselage...


The tail fin concerns me. it looks like a fatigue fracture across the base of the tail - a perfectly shear split in a perfect line. that is very strange.

How on earth can you say that... I don't think you'd know a fatigue failure if it landed on your bacon & eggs or sushi dish, whichever is appropriate!

Making judgements from pictures such as this on TYPE of metallurgical or composite failures is just RIDICULOUS... even from sample preparation and subsequent microscopic evaluation it still takes good consideration to say either 'Prior fatigue damage or just one-time overload'


There is some really silly speculation going on here, couched as statements not questions (which anyway would be almost as annoying)

To me, there would need to be a couple of REALLY SOLID pieces of evidence to begin down the 'fin separation' theory - even then without the FDR or VCR the EXACT cause (initiation) of this disaster would still be in doubt.

One of those would be to ASCERTAIN that the fin was found a VERY significant distance away from the bulk of the main mass components of the aircraft - e.g. 25 nm or so, AND in a direction back along the known flightpath

There would have to be other corroborating FACTS to start a good line of enquiry, which as I say, would still need the FDR to conclude the SEQUENCE and TRUE cause of events.

[stickyb]

As a computer guy (not in aero industry) I would question if we are seeing all the ACARS message.

For instance, the line with IR2 EFCS1X, IR1, IR3, would seem to have been truncated after the comma. I have no idea if the truncation is just a result of the printout layout used or if the message was truncated on transmission, but the fact remains we could be miissing some information on several of the lines.


.
http://img197.imageshack.us/img197/3410/acarsaf447e.png

[mixture]

Hasn't the ACARS been done to death by now......:ugh:

Stickyb...

would seem to have been truncated after the comma

The clue is probably in the words "libellé succint du message".

i.e. an abbreviation / brief summary / however you want to put it of the actual message. I would guess any truncations were intented and designed by a large commitee at Airbus, so I would suggest no need to start playing the X-Files theme tune.

[Junkers388L]

FYI, this is how an ACARS message looks when directly received from the aircraft (also an A330 in this case):

#CFB.1/FLR/FR0906091059 23333906PES 1,,,,,,,PCU(200MK)SR24A,HARD

Therefore, indeed, there may be truncation in the list circulated in this forum, whereas the BEA/Air France/Airbus certainly have access to the full picture.

Note: This ACARS message is just an example and totally unrelated to AF447!!!
But decoding of details relating to this ATA23 Communications failure welcome nonetheless :)

[Interflug]

I still don't understand, why the ACARS summary was published at all by AF/Airbus. I mean, being obviously a processed and prepared form of information all it does is deepening the speculations.
Isn't it totally against SOP to publish partial data so early in the investigation?
Has anyone a good explanation?

[Mad (Flt) Scientist]

I still don't understand, why the ACARS summary was published at all by AF/Airbus. I mean, being obviously a processed and prepared form of information all it does is deepening the speculations.
Isn't it totally against SOP to publish partial data so early in the investigation?
Has anyone a good explanation?

Er, it was a leak, not "published"?

AFAIK the only official word on ACARS was that BEA (or AF?) announced that there had been 24 messages, and the overall start and end time. The detailed content is not official, however reliable we might think it is.

Edit to say that the "er" is because I'm ASSUMING that to be the answer, not to disparage the question - as it might have appeared on re-reading

[Dysag]

Mixture: from what I've seen of Airbus, it doesn't work by committee. For one thing, they'd never be able to set a time when one of the nationalities wasn't out for lunch. Over there, one guy decides and the rest execute.

[Rananim]

The fact is it is a lightweight component that floats
Perhaps too lightweight..theres irony in what you say...

[Mudfoot]

Content deleted, erroneous information. My apologies... :(

Cheers, y'all.

[Lost in Saigon]

In regards to the ACARS messages has anyone had a chance to preview this link?

Innovation Analysis Group (http://www.iag-inc.com/premium/)

A Honeywell expert goes thru the list of AF447 ACARS messages and tells viewers what has likely happened.


This "Expert" is suspect in my eyes because he does not mention the "Cabin Vertical Rate" message at any time. He implies that the 02:14z message is just an advisory about the ACARS itself.

It appears he was not given all the information that is available. If not, where does all the talk of "Cabin Vertical Rate" originate?

[infrequentflyer789]

In regards to the ACARS messages has anyone had a chance to preview this link?

Innovation Analysis Group (http://www.iag-inc.com/premium/)

A Honeywell expert goes thru the list of AF447 ACARS messages and tells viewers what has likely happened.

I just had a listen, for a laugh, and switched off about halfway through.

Interviewer and "expert" seemed to get completely confused about what alternate law was, and then appeared to conclude that the mesage about reversion to alternate law must indicate failure in the flight control computers.

Even with my limited and datred knowledge of how airbuses are put together, it is clear that there is far better, clearer, and more credible analysis of the ACARS data on this thread.

[infrequentflyer789]

Perhaps too lightweight..theres irony in what you say...

Not sure what you are implying, unless you don't understand that there is not necessarily a correlation in engineering (particularly in aviation) between weight and strength.

[Tagron]

I have a question.

As a mere engineer, I understand the problems of high altitude flight with the proximity of stall speed and overspeed.

With the known problems of pitot icing (though I have never seen it) why don't you pilots just stop flying so high when there are storms about? Would it not be easy to mandate a descent to a lower FL where the speed range is greater so you have more time to react if something goes wrong?

Yes I know it costs money, but so do crashes.


Steve,
the answer to your question is that the preferred method of CB avoidance is lateral rather than vertical. Best of all one avoids a whole system but when this is not possible (as is frequently the case) the method is to find a route between individual cells, not penetrate any of the cells themselves. Often this is easier when higher because the gaps between the cells
are greater. Also many CBs do not reach cruise altitude. Sometimes lower altitude can involve worse weather.

My own experience is that operating at normal optimum altitudes is satisfactory provided that adequate lateral separation from CB can be achieved. Careful monitoring and readiness to intervene on speed and thrust are part of the process.

The issue of probe icing is one I have not encountered, nor I would guess, have most readers,and it would appear to be type specific to A330/340. It would also appear, judging from the reports from previous contributors, to occur in specific circumstances, notably layer cloud around the CB e.g.the anvil, even though the CB itself has been avoided.

It is of course true to say that if airspeed indications are lost, lower altitude does give a greater range of speed availability, therefore the crew's task is easier. In all cases judgements have to be made according to the circumstances.

[stezam65]

To swedish steve:


A pilot always try to fly at OPTIMUM altitude, which is the altitude where you have the best kilometric endurance and you have a good margin to the low and high stall speed.

In Europe is always quite easy to fly at that altitude because, even if there are many planes flying around, the separation in height between planes are reduced (1000 feet between converging flights). The longitudinal and lateral separation between planes is also reduced because Air Traffic Controllers use the radar.

Across the Atlantic Ocean the longitudinal separations are very big (planes that follow the same route is 10 minutes of separation, i.e.80 nautical miles) and the vertical separation is double (2000 feet between converging flights).

So, at the start of Atlantic crossing if the pilot take the altitude which is not the optimum but nearly the maximum at that moment, is very happy because if there is bad weather in front of him, he will have more chance to overfly it (anyway the pilot, in the evaluation of the chosen flight level always have to think about ahead forecast turbulence).

If there is bad weather, the pilot has to use the weather radar, scans the sky in order to understand if he is able to overfly it or he has to change route in order to circumnavigate thunderstorm cells.

The job of the pilot is to evaluate and mainly take the decisions which are not the ideal but a compromise.

Anyway if the plane enters in a permissible cloud, pilot knows that the plane has a protection against ice built-up using airworthiness antice devices.


After this accident I know that Airbus had some troubles concerning the anticing of the pitots. If there is ice build-up in the pitot the airspeed indicated to the pilot (the speed that show the margin to the low and high stall speed) is unreliable.
See also this link
http://alphasite.airfrance.com/s01/?L=2 (http://alphasite.airfrance.com/s01/?L=2)

Anyway, there is a procedure called: flying with “UNRELIABLE SPEED INDICATION”.
In this procedure the pilot has to fly the plane with precalculated attitude showed to the PFD’s (primary flight displays through IR1, IR2, IR3 and ISIS) related to the phase of flight and applied the correct power to the engines in order to fly predetermined speed.

This emergency procedure is very difficult but I think that the Air France crew was able and well trained to follow, to manage and apply it.

This is the time to do again the question:BUT DID THE PILOTS HAVE THE ATTITUDE INDICATIONS ON PFD’s?

Answering this question will also answer the other: why the rudder could be detached? Without airspeed they didn’t have the Rudder Travel Limiter.
And without attitude indication, the flight could be so unstabilized that if not using the rudder with care the rudder could be damaged and detached
loosing, may be, the pressurization.


Now Swedish Steve, I ask you again to explain me better what you answer me using simple and comprehensive English (sorry, English is not my native language)


I ask again to other professionist people to clarify the line written in the Acars messages: did the AF447 flight also have IR’s failure?

Thanks
Stef

[MLT]

1) With the autopilot disconnected, and flying in the dark, through the ITCZ, with questionable weather conditions (as described by Tim Vasquez), would the rudder be extensively used to help maintain level flight?

2) If the answers to the above is yes, with unreliable airspeed data, and the possibility that the rudder wasn't accurately limited, could it be possible that the crew in trying to control the aircraft in difficult conditions over boosted the rudder which in turn over stressed the vertical stabilizer? From an engineering perspective, I would say yes it is...

MLT

[Graybeard]

The pitot tube probably has a bleed hole for water egress, so icing might cause airspeed to decay somewhat gradually, even to zero. Sorry I don't have access to exact info.

GB

[hefy_jefy]

At the very start of this tragedy it was said in the press that they did not know exactly where this aircraft had ended up. Is the GPS position not part of the ACARS data packet? If not why not? Seems odd that a new aircraft with much sophisticated reporting would not continually transmit its position...

[keithl]

Request for background info: The A320/330 are not brand-new aircraft. Why would pitot tubes / probes start acting up "from May 2008"? Why not throughout aircraft life?

[Graybeard]

ACARS message costs are paid to a service provider, so message length and frequency are kept to a minimum. There is probably one in 100,000 messages where the lat/long would have any value. They have ELT for that.

GB

[augustusjeremy]

Does anyone have the logical diagram(s) for the Rudder Travel Limiter Fault ?

[diddy1234]

from various Acars messages that I have seen they only report position when requested by the airlines maintenance depot.

[wes_wall]

Dutch Bru

The report mentions explicitly that some French airline companies, in particular those that fly long distance routes, have dedicated departments that communicate via ACARS on updated weather situations en route. Where those departments are then specifically tasked with providing specific updates on weather to flightcrews.


Good find, and thanks. I think that potentially solves and puts to rest the question regarding the crew sent turbulence message.

[tubby linton]

I made a comment about rudder travel limiting last night based upon the fcom for my aircraft but another poster found an alternative description of how it works in a different reference.
The trouble with comparing aircraft is that Airbus are not all the same.My airline flies a mixed bag of 320 family that have some major differences in their systems.The manufacturer are always "Improving" the aircraft so unless you know which mod standard your fbw computersare you cannot know which logic applies.I have also expereinced incidents where the computer mod standard was different to that in the fcom and it can take many months for the fcom to catch up.
Unless we know the mod state of the SECs on this aircraft we will not be certain which logic applies.

[Finn47]

The position where the first ACARS message was sent is indicated here on the BEA website:

http://www.bea-fr.org/anglaise/actualite/af447/reconstitued.flight.path.jpg

[411A]

Does the A330 suffer from any dutch roll with the AP disconnected at altitude? If it does then I presume that the rudder would be used quite a bit.


Normally, I wouldn't comment on this type of accident until more facts are known, however...the above statement I suspect is indicitive of a present day general lack of swept-wing aircraft aerodynamic knowledge...IE: if dutch roll conditions should develop (especially, at higher altitudes), the last thing a pilot would want to do, is have pilot applied larger rudder inputs, because....this will make the dutch roll conditions much worse, not better.
A known fact, decades ago, but I now suspect...totally forgotton, or never taught.:{

[Lost in Saigon]

The position where the first ACARS message was sent is indicated here on the BEA website:

http://www.bea-fr.org/anglaise/actualite/af447/reconstitued.flight.path.jpg


That position is only based on a projected track and distance from the actual time of the INTOL position report, and the estimated time of arrival overhead TASIL.

It is probably fairly accurate but could be off by many miles if they were deviating around the thunderstorms.

[ELAC]

@MLT

1) No.

2) No.

3) Anything is possible, but is it probable, no.

As a general note on this thread, despite having flown the A330 for 11 years and FBW Airbuses for 16 years, there are, for me, too few established facts to make for anything other than completely uninformed speculation so far. Hence, I and many of the other frequent contributors to Airbus related threads have withheld most comment.

Most of what your reading here has been generated by those who don't know the aircraft and has more to do with the pet theories of the uninformed/unaware and the usual cranks riding their favourite hobbyhorses than it does with any practical discussion of the A330's systems or operating procedures. How about, before choosing to post each of us asks whether we have sufficient knowledge of either the aircraft or the circumstances to make a meaningful contribution to the thread? If not, and if it's an idle curiosity question based on what you don't know, then don't post.

If I read another contribution that states that the pilots must have been flying too high into "coffin corner" for their weight, or that the automatics must have all "failed" at the critical moment leaving the pilots incapable of controlling the aircraft, or that the aircraft was incapable of being controlled I swear I'll chuck my cookies. There's no information to support any of these premises (unless coffin corner is now more than 50 kts wide) or most of the other theories that have been suggested. When real facts become available let's discuss them based on knowledge of the aircraft and of the conditions our colleagues faced. Till then let's give the meteor/bomb/over-controlled rudder/all automatics lost rendering aircraft impossible to control posts a rest.

ELAC

[mixture]

ELAC ...

I'm glad I'm not the only one that's fed up with all the speculation ranging from the almost delusional people with a vivid imagination to the armchair scientists who think they can analyse metal fatigue from a low resolution digital photograph downloaded over the internet.

Well said ! Remind me to buy you a beer sometime ! :cool:


EDIT :
Just to clarify in public .... I don't know about ELAC, but I just wanted to confirm that contrary to a PM I have just received, I was not targetting anybody in particular with my post above. I was merely commenting on the general "goings on" in this thread !

[overthewing]

I'm assuming there has to be a preliminary report produced - does anyone know what the time limit is on that? And is likely to contain the (official) ACARS messages?

[Celestar]

@Stezam65

Across the Atlantic Ocean the longitudinal separations are very big (planes that follow the same route is 10 minutes of separation, i.e.80 nautical miles) and the vertical separation is double (2000 feet between converging flights).

Atlantic (MNPS) was the first zone worldwide with reduced vertical separation of 1000ft as far as I know, or I misunderstand your comment?

[cesarnc]

@overthewing

French authorities said they will have a preliminary report by the end of June.

Investigation will be carried out by French authorities, while Brazil will help with SAR, debris recovery and identification of the bodies.

[Lightning Mate]

ELAC,

:ok::ok::ok::ok::ok:

:ugh:

[DC-ATE]

Swedish Steve -
As a mere engineer, I understand the problems of high altitude flight with the proximity of stall speed and overspeed.
With the known problems of pitot icing (though I have never seen it) why don't you pilots just stop flying so high when there are storms about? Would it not be easy to mandate a descent to a lower FL where the speed range is greater so you have more time to react if something goes wrong?
Yes I know it costs money, but so do crashes.

BINGO.....you done broke de code !! Unfortunately, conservatism no longer exists in the airline industry. Flights are treated as "missions" now. And I don't want to hear from other pilots on here that "all pilots aren't like that." I know that, but it only takes a few to give us all a bad name.

[overthewing]

@cesarnc, thanks.

I'm hoping the report will clear up the question of how they got the information that the plane was in 'hard turbulence'. If it was via ATC, then they must have been in turbulence a bit before 02.00, I think? If it was via ACARS, should that have been part of the ACARS report that was leaked, or do pilot-entered transmissions get dealt with differently? If it was, in fact, an AF department informing the crew of 'hard turbulence' ahead, wouldn't AF have expected them to change course to avoid?

[Edited to correct time.]

[shawk]

Thanks, ELAC. :ok:

[Lost in Saigon]

LUALBA posted this morning what purported to be a dispatch from Airbus.

It included:

The data available at this stage of the investigation:
- does not suggest any loss of electrical power supply,
- does not suggest a loss of instrument display.

If this is genuine, it seems they missed an opportunity to clarify (if they know from the ACARS) the serviceability or not of the weather radar. Or do I have to decode the above? i.e. "instrument display" includes the radar?


I think far too much importance is being put on these ACARS messages.

ACARS is not required to be onboard an aircraft. It is a handy feature to have, and can be quite useful, but it is also subject to errors and failure itself. At this point in the investigation, there is no way to know how accurate these messages are.


Just so you all know:

1) Many jet airliners do not have ACARS installed or the airline chooses not use the system at all. (cost factor)

2) Many jet airliners that do have it installed do not have SATCOM capability and the system is useless over water.

[ELAC]

@DC-ATE

How about sticking to what you know?

At FL350 and 210 tons my A330-200 (slightly different engines) would have had a barberpole at M.86 of 292 KIAS and a Vls 1.3G of 241 KIAS, a spread of 51 kts. A M.80 cruise would have been at 272 KIAS and the recommended TAPS would have been 260 KIAS. At either speed there would exist an approx. 20 KIAS margin to the nearest limiting speed, let alone the nearest actual buffet speed. That's a pretty wide margin to operate within and hardly anything like a coffin corner. How much more room do you think they should have had? I'd be willing to bet your fine Deisel 8 probably didn't have as much a of margin at the altitudes you routinely chose in similar conditions, unless you liked flying around in the 20's. And if you did, I'll bet you saw a lot more bouncing around than most of your colleagues.

One could make the argument that, possibly, the incident might have been avoided if only the aircraft was flying at a higher level. FL370 would have been well within the aircraft's operating capabilities and if reports here are correct another aircraft following the same route just 10 minutes behind at FL370 reported making no more than normal deviations to avoid weather and no encounters with unusual levels of turbulence.

Was flying lower at FL350 in the junk versus in the clear at FL370 a factor? Who knows, but it's a better theory than suggesting, without evidence, that a 50+ kt. window between limiting speeds at FL350 was an insufficient margin of safety.

ELAC

[borghha]

to overthewing:

the preliminary report is expected towards the end of this month, according to a BEA statement.

[Flap 80]

Dont know about the 330 but on the 320 series all the power for the pitot/static and window heat is channelled through one switch on the overhead panel. Could a simple internal switch failure render all the heating to these components inop.On the B737 the same items are controlled by 4 switches.

[wileydog3]

The fact is, we know from previous experience and from Airbus admission that the fin is very sensitive to excessive sideloads.

WAY back when I was flying the KC-135 (the old water-wagon in the early 70s), the dash 1 cautioned against strong inputs to the rudder noting it could induce significant loads.

It doesn't take but a casual glance to see it IS the largest control surface and thus it can create huge forces. When we were doing hard-over rudder training, it was eye-watering to see how quick a hard-over could roll you through 90deg. BIg surface.. big forces.

[Dysag]

LUALBA posted this morning what purported to be a dispatch from Airbus.

It included:

The data available at this stage of the investigation:
- does not suggest any loss of electrical power supply,
- does not suggest a loss of instrument display.

If this is genuine, it seems they missed an opportunity to clarify (if they know from the ACARS) the serviceability or not of the weather radar. Or do I have to decode the above? i.e. "instrument display" includes the radar?

[Futura Rider]

As most carriers use averages for baggage weight & passenger weight but actuals for the AirCargo units, the most likely area for weight error is not the air cargo (Frt, mail) load but rather in the bgge / pax weights. I know there is a fudge factor built into the W&B but have always wondered how close the average wt was to the actual all up load (Pax, Bgge & Cgo).Actual cargo weights that are usually provided by the shipper.

If they are off, then the mistake goes un-noticed. I just learned of a recent air cargo shipment (on a pax carrier) that was reported under by 1500 lbs and not noticed until customs on the recieving end flagged the shipment for inspection because the wt was off.

That's just one pallet of cargo. Add that to the high probability of pax and baggage weights being off and you have a potential beginning link in the accident chain for quite a few flights every day.

I've experienced quite a few Max Gross takeoffs that barely got off the runway with two engines operating. If an engine had failed after v1, the takeoff would likely not have been successful.

So yes, it is possible that AF447 could have weighed more than the crew thought it did, but so do many flights that are operating every day.
A contributing factor? Maybe.
A direct cause? Probably not.

[tubby linton]

I would imagine that by Display the dispatch means the DMCs (Display management computers)and associated CRT or LCD displays in front of the pilots.There has never been any suggestion that these failed only the data that would normally be indicated on the screens.

[Config Full]

http://www.fab.mil.br/portal/voo447/FOTOS/090609/foto1.jpg

[DC-ATE]

ELAC -
How about sticking to what you know?
I'd be willing to bet your fine Deisel 8 probably didn't have as much a of margin at the altitudes you routinely chose in similar conditions, unless you liked flying around in the 20's. And if you did, I'll bet you saw a lot more bouncing around than most of your colleagues.

[Thank you for your reply, but it's actually DIESEL...picky, picky]

Well, I don't know everything, but I know/knew enough to avoid areas such as the one in question by enough margin that I never really had to worry about it. Did I burn a lot of extra fuel? You bet I did, and we all got home with a safe, smooth ride. And, I did NOT choose those altitudes that did not provide the margin I felt necessary. This is far from an exact science and the sooner some pilots realize that, the better off we'll all be.

As to the remark about flying in the 20's. I once flew from ORD to LNK (about 400 nm) at TEN thousand feet to avoid the chop that EVERYONE was complaining about at just about ALL of the higher altitudes. We never got a ripple. All ya gotta do is listen to others and experience it yourself to know.

And: One could make the argument that, possibly, the incident might have been avoided if only the aircraft was flying at a higher level.

One could make the argument that, possibly, the incident might have been avoided if only the aircraft.....had avoided the area completely.

[Chicago567]

RE: message 842.

Two points of interest from the Honeywell person: The messages are sequential from when the autopilot disengaged. The Pitot errors occured after the main events and could indicate that the heaters went out (electrical) or blockage (ice).

[Interflug]

How about sticking to what you know?

At FL350 and 210 tons my A330-200 (slightly different engines) would have had a barberpole at M.86 of 292 KIAS and a Vls 1.3G of 241 KIAS, a spread of 51 kts. A M.80 cruise would have been at 272 KIAS and the recommended TAPS would have been 260 KIAS. At either speed there would exist an approx. 20 KIAS margin to the nearest limiting speed, let alone the nearest actual buffet speed. That's a pretty wide margin to operate within and hardly anything like a coffin corner. How much more room do you think they should have had? I'd be willing to bet your fine Deisel 8 probably didn't have as much a of margin at the altitudes you routinely chose in similar conditions, unless you liked flying around in the 20's. And if you did, I'll bet you saw a lot more bouncing around than most of your colleagues.

One could make the argument that, possibly, the incident might have been avoided if only the aircraft was flying at a higher level. FL370 would have been well within the aircraft's operating capabilities and if reports here are correct another aircraft following the same route just 10 minutes behind at FL370 reported making no more than normal deviations to avoid weather and no encounters with unusual levels of turbulence.

Was flying lower at FL350 in the junk versus in the clear at FL370 a factor? Who knows, but it's a better theory than suggesting, without evidence, that a 50+ kt. window between limiting speeds at FL350 was an insufficient margin of safety.

ELACAnd you do know the weight was 210 t? Also you do know what the precise temperature was?

Could you just for fun do the math again with 220 t and ISA+15 ?

[bmrider]

Thanks Dysag.

By the way, the bomb threat to an AF flight from BA to Paris has just been clarified. A former AF employee, fired a few days before such flight, called from his cell phone to Air France office and made the threat. I came up in the local news this morning. The guy will face charges.

[Config Full]

@Chicago567 (http://www.pprune.org/members/302369-chicago567)
The Pitot fault is the first event. In the sequence you should read the fault messages first and the warning messages after.

[ClippedCub]

The roll was due to yawing a swept wing - not the rudder. Left rudder, by itself, would tend to create a roll to the right since the vert is above the aircraft Cp, or cg. The resulting roll to the left is due to yaw, or un-sweeping the right wing - increasing lift on that side, and increasing the sweep of the left wing - decreasing lift on that side. Hence the roll to the left. Works subsonically and transonically.

[PJ2]

411A;
the above statement I suspect is indicitive of a present day general lack of swept-wing aircraft aerodynamic knowledge...IE: if dutch roll conditions should develop (especially, at higher altitudes), the last thing a pilot would want to do, is have pilot applied larger rudder inputs, because....this will make the dutch roll conditions much worse, not better.
A known fact, decades ago, but I now suspect...totally forgotton, or never taught.

Concur, 411A. Seen it in major carriers as well and not just the smaller outfits. It's barely bread-and-butter training all the way down. Along with instruction on high-altitude flight, more-than-basic met (thunderstorms, windshear, frontal analysis etc etc etc), anything on swept-wing flight (what's a 'yaw damper?") and how to do a proper visual approach in a transport aircraft, I have never seen a course on radar use either. In a recent conversation with colleagues, I am informed few know how to use the B777 radar either, with recent, "interesting" results in the same ITCZ.

The lo-cost mentality now embraced by all airlines, has taught passengers to expect and demand $1.49 fares in exchange for on-time, completely-safe transportation by highly-experienced, fully-trained personnel. Those illusions are coming home to roost.

Passengers can't have it both ways nor can airline owners or managements.

The industry has driven the airline-pilot profession into a place and into such a state of disrespect and relative poverty where nobody wants to come to it anymore when there are far greener fields elsewhere with far less risk and a more secure future. "Love of flying" just doesn't do it anymore.

The industry is hiring the relatively-inexperienced-and-basically-trained because, as I said two years ago, the pipeline is drying up, and is leaving the training of these issues which rightfully belong in every professional airline pilots' toolkit, to "home-study".

This is NOT a comment on the AF crew. This is a comment on where this profession has been taken/pushed by forces and priorities which do not comprehend aviation but which nevertheless manage large airlines. Back to the thread.

All we know is, the vertical stabilizer came off at some point during the accident sequence. The evidence is, (as I posted) extremely thin so nothing may be concluded except the VS is off the airplane and intact, with rudder, with slight damage to the bottom/rear of the structure and a possible, though not proven, presence of at least one fastening lug. Hopefully photos will emerge soon and that notion can be proven/disproven.

THAT said, the presence of the lug, (should it be there), proves nothing more than "the fin broke off the airplane". Possibly, as has been suggested, analysis of the failure modes (bent sheet metal, tear lines, telltale scratches, torsion and tension fractures) done by qualified engineers may inform us further. Until then, we only know that the fin broke away. We know nothing about pilot inputs or the severity of lateral loads sufficient to break the fin off. It happened and whatever did it had severe force way beyond the design limits of this and, I suspect, any transport aircraft.

In terms of conducting a search for the main wreckage, assumptions must be made in order to use resources efficiently in the large area under consideration so it makes sense to build scenarios and assess reasonableness then begin. It is logical and not merely speculative to expect that the fin's location, given last transmitted aircraft position, winds and currents will be in the main wreckage's proximity. A "radius of action" can be maximally and minimally determined, outside of which the location of the fin would not be possible and a search conducted rationally. One expects that these processes are already either underway or now even complete and a search begun with the advertised deep-sea robotic equipment.

There remains absolutely no evidence whatsoever of pitot or TAT icing, hot-rising-air-in-thunderstorms, (anectdotal testimony is interesting but if it was that hazardous, we'd be hearing a lot more about it) and no evidence whatsoever of "coffin corner" issues. I know that specialists have contributed a great deal of knowledge regarding interpreting the messages but the ACARS messages do not place such conclusions beyond reasonable doubt. All notions remain entirely unsubstantiated theories. There is nothing anyone can post that will change this state of affairs. Because we know so little and there is so little "trace", we must demand very high standards of any new evidence and be careful not to wander beyond what that evidence can tell us directly.

ELAC;

As usual, first class call - spot on.

[BreezyDC]

Just FYI, the recently released CVR report from USAir 1529 (http://http://www.ntsb.gov/Dockets/Aviation/DCA09MA026/420471.pdf) notes the CVR pinger did not activate as it should have when shorted by water.

The underwater locator beacon (ULB Dukane Model DK100, s/n DM1661, battery expiration date October, 2009) did not function when tested. After shorting the center electrode to the case, no sound was detected using a Dukane Ultrasonic Test Set Model 42A12. The beacon was also tested using a Dukane Test Set Model TS100, which indicated “Open Probe/Batt.”

Hopefully not a problem with those on AF447.

[gilot]

as a AF B747 captain,i do confirm that we have a dedicated weather departement which occasionaly send some infos via ACARS in case of turbulence.
the last one i received (about turbulence)was when we were heading to FAI (AK, USA).
as long i can remember it was something like;
severe turbulence forecast from XXhrs valid till XX hrs.
position X° N X°W to Y° N Y°W.
from FL 250 to FL 410.
RIP

[Interflug]

is "forte turbulences" common terminology with AF pilots to communicate the strength of turbulence? Thank you.

[Config Full]

@ PJ2
I read in the Air Caraibe (ACA) Report which was posted here that actually the rise in air temperature is due to ice build-up on the pitot and the TAT probe. The TAT probe picks up the temperature of the ice, which is higher, rather than actual air temp.

[jimpy1979uk]

There has been a lot of attempts to decode the ACARS messages. The messages that have been sent are normally then fed into the companies version of AIRMAN which is a maintenance tool. The ACARS transcript is raw data.

This data would then take the look of the Post Flight Report. In fact it looks exactly like what you get out of the flightdeck printer with cockpit effects on the left and maintenance messages on the right.

[PJ2]

Config Full;

Thanks - taking a look at the report - my French is poor but one can get a gist of it.

I see the fin is ship-board so perhaps soon we'll see a photo of the area where the attach points are.

[gilot]

hi interflug.
yes the term severe is standard.as they gather their information with sat survey or any other informations sources.

like this one.
http://www.star.nesdis.noaa.gov/smcd/opdb/aviation/turb/tidaily/TIAVN18a.GIF
.
but it s obvious that we don t received any messages from them if we re crossing the ITZ or the the bengal gulf during the monsoon.cause it will be useless .

[ELAC]

@DC-ATE

DIESEL, not DEISEL... absolutely right, thanks for the correction.

Well, I don't know everything, but I know/knew enough to avoid areas such as the one in question by enough margin that I never really had to worry about it. .... This is far from an exact science and the sooner some pilots realize that, the better off we'll all be.

And what makes you think the AF pilots didn't think the same? We really don't know what sort of deviation they chose except that there's no record of them making a request to ATC. But, on a bad night with HF communication that in itself means nothing. Until data proves otherwise it's unfair to suggest that these pilots were using any less diligence than you would have. Remember all the plotted tracks we've seen are assumed, not actual. And, as you say this is far from an exact science, which means that even when you are certain you are making prudent choices there is the chance you may still be wrong, no matter how smart one may be.

One could make the argument that, possibly, the incident might have been avoided if only the aircraft.....had avoided the area completely.

Which area? The entire South Atlantic in the vicinity of the ITCZ as my last taxi driver suggested? Perhaps they should have just stayed in RIO until the weather was better, but then if they did they'd probably still be there wouldn't they? The ITCZ's a fairly continuous phenomena. Without knowing what route they took through the area and where they were relative to what they could see of the weather (visually and/or on the radar) we don't know enough to draw any conclusions as to the wisdom of their choices.

ELAC

[golfyankeesierra]

411A;
Quote:
the above statement I suspect is indicitive of a present day general lack of swept-wing aircraft aerodynamic knowledge...IE: if dutch roll conditions should develop (especially, at higher altitudes), the last thing a pilot would want to do, is have pilot applied larger rudder inputs, because....this will make the dutch roll conditions much worse, not better.
A known fact, decades ago, but I now suspect...totally forgotton, or never taught.
Concur, 411A. Seen it in major carriers as well and not just the smaller outfits. It's barely bread-and-butter training all the way down.

Sorry Guys, you have to stop.
It really gets annoying that after every accident someone needs to point out that younger pilots can't fly and and training isn't what it used to be.

This was an experienced crew!

And even after and despite this tragic accident, aviation still remains safer then it has ever been.

[avspook]

PJ2

r. In a recent conversation with colleagues, I am informed few know how to use the B777 radar either, with recent, "interesting" results in the same ITCZ.

Until recently I used to run the engineers through the FFS (747/A320/777) showing them Radar Operation typical screens & failures.
I used to teach radar maintenance for one of the OEM's
I have never done it or had it requested by the Crew, or the airline

This thread has had a few drivers knocking on my door over the last week that awareness HAS to be a plus

[727gm]

Back in the aftermath of the JFK AA accident, it was interesting to read in Aviation Week the article comparing the various manufacturer's philosophies on cockpit design & rudder force limitation.

I don't have a link, but as I recall, the Airbus design included both a relatively small breakout force to get the pedal to move, coupled with an surprisingly small displacement(travel) and low (additional) pedal force required to reach full input.

Imagine a loss of autopilot in severe turbulence/IMC/at altitude coupled with a loss of rudder load-limiting.......with a cockpit rudder control that requires very little pedal force and travel to apply maximum inputs. The means of load limiting vs. airspeed at the control surface varied between manufacturers, I don't recall the Airbus system.

If this were the case, the tail departing the airplane may be the cause of all the other error messages. The engines would depart shortly after.......

[BOAC]

Sorry Guys, you have to stop.- well said.

One mention of 'Dutch Roll' and out come all the gum-bashers from under the stones - "ee - when I were a lad....".

Did they get any? Possibly.
Did they not get any? Don't know.
Is it really pertinent? No.

NEXT! Relevant posts would be nice.:ugh:

[worrab]

Even the media have backed off. Given that there's NO new electronic messages, NO new met, NO CVR, NO FDR and precious little new evidence it will be interesting to see the next relevant post that has something new to say.

[Joss]

This is reaching a point where it is becoming apparent that the information available at this time does not offers any answers. For every theory there is another one that goes in the opposite direction and is as good as the first one.

Why don't calm down a little bit a try to piece together what we really have so we have a place to start when new evidence shows up?

Anyone cares to try?

[testpanel]

Sorry Guys, you have to stop.
It really gets annoying that after every accident someone needs to point out that younger pilots can't fly and and training isn't what it used to be.

This was an experienced crew!


Is a F/O with (ar.) 3000 hours, experienced in wide-body long-haul?
If I look back to myself now, sorry, i was not......

I teach/exam in the sim and the real-a/c, crm-thing I use the last 3 months is the bufalo and the amsterdam; they both stalled a perfectly good airplane..........(i do agree a little with the (not-so-)-old guys:ok:)

[DC-ATE]

ELAC -
Without knowing what route they took through the area and where they were relative to what they could see of the weather (visually and/or on the radar) we don't know enough to draw any conclusions as to the wisdom of their choices.

Fair enough. However, other flights apparently got through that area, not only that night but other nights as well, without problems. As we keep saying, we'll know when we know and even then, we probably won't !!

[Safety Concerns]

The messages also showed that the autopilot was off, though it was impossible to say whether it had disengaged itself, as it is designed to do when it receives suspect data, or whether the pilot had decided to turn it off, Arslanian said.Can we now stop the uninformed chat about manually disengaged autopilots not appearing on ACARS or are the investigators also badly informed?

It would be far more useful if people would investigate rather than opinionate

[wileydog3]

BIg surface.. big forces.
The roll was due to yawing a swept wing - not the rudder.

I understand the aerodynamics of roll solely from rudder and I had demonstrated to me in the tanker that one could be in 60 degrees of bank and roll out on a heading when starting only 5 deg from the desired roll out heading.

And as I remember the tanker dash 1 said that a hard rudder could put the airplane beyond 90deg bank in less than 3 seconds. That is a very big force.

[Rockhound]

ELAC,
Correct me if I misunderstand you, but it seems to me that you're implying the AF crew did deviate from track? Doesn't the evidence (comms from the crew, ACARS transmissions, location of wreckage and debris) indicate that AF447 stayed on track and flew into, or found itself in, a major storm cell?
Rockhound

[ketuomin]

So many questions/theories flying around anyone interested to compile some FAQ with possible threads and at least some facts which has been surfaced so far. In any cases major accidents this forum discussion comes easily bloated with various sides and opinions and only by reading whole thread you can follow thru what's the opinions / findings.

Any volunteers who has followed thru things along this thread to do some FAQ for things to look for ?

[kbootb]

So many questions/theories flying around anyone interested to compile some FAQ with possible threads and at least some facts which has been surfaced so far. In any cases major accidents this forum discussion comes easily bloated with various sides and opinions and only by reading whole thread you can follow thru what's the opinions / findings.

Any volunteers who has followed thru things along this thread to do some FAQ for things to look for ?


already done at Air France Flight 447 - Wikipedia, the free encyclopedia (http://en.wikipedia.org/wiki/AF_447)

[ELAC]

And you do know the weight was 210 t? Also you do know what the precise temperature was?

Could you just for fun do the math again with 220 t and ISA+15 ?

@Interflug

See, this is my point about uninformed comment & questions. These questions reflect a lack of understanding about the aircraft and the nature of its indicating systems.

No, I don't "know" that the weight 210T, and I don't know what the "precise" temperature was.

What I do know, however, is that the MTOW of this A330-200 was 233T, and that according to my handy-dandy FCOM 3 the initial fuel flow at FL350 at 230T and ISA+15 is 6730 K/hr. and at 210T is 6165 K/hr. (actually slightly different due to different engines, but only slightly). As the aircraft was, according to the records, airborne for at least 4:11 (22:03-02:14?) I can deduce that its weight at the time of the accident was no greater than 233T - (4.2*((6730+6165)/2) = ~205.9T. Probably it was less than this, but I don't know the actual TOW nor do I have the desire to try calculating a climb fuel burn, but in any event 210T is a conservative value, unless you want to revive the baseless overloaded aircraft theory again.

I also know that the speeds I quoted to you for the weight are KIAS (Knots Indicated Air Speed), so they themselves will not change with a change in temperature.

As per the above calculation the aircraft's weight could not be 220T after 4 hours of flight unless the aircraft was very grossly overloaded, and the speeds I quoted do not vary with temperature. So what I do know is that there is no meaningful answer to your questions.

A question you didn't ask, but which might be relevant is the aircraft's altitude capabilities at its assumed weight at the time of the accident. For my aircraft with slightly different engine performance they are:

@ 210T and M.80

Optimum Altitude = FL360
Max. Alt. @ ISA+20 = FL370
Max. Alt. @ 1.4G Margin = FL378
Max. Alt. @ ISA+10 = FL385
Max. Alt. @ 1.3G Margin = FL394

So, again, given that the weight was if anything less than 210T, the choice of FL350 was an entirely reasonable one from a performance perspective and, in fact, probably below the optimum altitude (which as displayed to the pilots would also be modified by temperature, wind speed/direction and cost index) for the aircraft at that weight. This would go some ways towards explaining why I find suggestions that they were flying too high in a coffin corner so ludicrous.

ELAC

[etesting2000]

There had been some talk earlier that we as humans did not have the capability to search to the depths where this incident occured. This has recently changed. Woods Hole Oceanagraphic Institute demonstrated 6.8 Miles at the bottom of the Mariana Trench on May 31, 2009.

link to press release

News Release : Hybrid Remotely Operated Vehicle “Nereus” Reaches Deepest Part of the Ocean : Woods Hole Oceanographic Institution (http://www.whoi.edu/page.do?pid=7545&tid=282&cid=57586&ct=162)

[Lost in Saigon]

ELAC,
Correct me if I misunderstand you, but it seems to me that you're implying the AF crew did deviate from track? Doesn't the evidence (comms from the crew, ACARS transmissions, location of wreckage and debris) indicate that AF447 stayed on track and flew into, or found itself in, a major storm cell?
Rockhound

We have no idea if AF447 stayed on track. All we have is their last position report at INTOL. That is their last known position.

Everything else is speculation.

Correction: The last known position would have been when they went out of radar coverage approximately 15 minutes past INTOL.

[PJ2]

golfyankeesierra;
Sorry Guys, you have to stop.
I agree with you if you mean those who extrapolate small amounts of evidence into broader theories/conclusions about what occurred.

It really gets annoying that after every accident someone needs to point out that younger pilots can't fly and and training isn't what it used to be.
Why does it "get annoying" for you? A comment about the level of training and relative absence of experience in high-performance transport aircraft is not about offending or annoying, it is about informing and even challenging the present circumstances in which both airlines and new pilots find themselves. Who is going to come to this profession for sixteen-thousand a year and the kind of training regimes new pilots must accept from their employer who themselves are only trying to make a buck and stay in business? This is much, much more than about stars in one's eyes about aviation, that wonderful love of flying that drives many to arrest all other activities in their lives to follow their dream.

This is a complex matter about the present practicalities of the career which I and other poster have dealt with thoroughly in other threads and which, if you haven't, I kindly invite you to read and consider. We cannot and should not deal with it here.

This was an experienced crew!
No disagreement there given that this was Air France. I have already stated (in bold font), that "my comments do not apply to this crew".

And even after and despite this tragic accident, aviation still remains safer then it has ever been.
I and all who fly (past tense in my case) professionally understand this very well and would agree, so I'm not certain what you're trying to convey. The larger message from the post you're quoting from is, while you're observation is correct, the accident trend and issues outlined elsewhere are not pointing to a continuance of that trend, (low accident rates, safest means of transportation etc etc), and a lot of safety specialists "have their radar on" as it were and are speaking out, loud and clear. The issues I describe above and more thoroughly in other threads are serious, immanent issues in this industry which, if left unaddressed, have the potential to turn the industry's admirable safety record around.

Let me ask in the face of the accidents since the tragic and avoidable MD80 one at Madrid, where are the "Sully's" of professional transport aviation? Such a statement is perhaps quite a direct and pithy way of stating the issue, but there it is - sometimes "pithy" is the shortest way to communicate overarching concerns. We have three accidents, (Madrid, Buffalo, Amsterdam) which have resulted from basically stalling an airliner and which have killed a lot of our passengers. That's unacceptable.

PJ2

[Swedish Steve]

already done at Air France Flight 447 - Wikipedia, the free encyclopedia

But makes me wonder who considers themselves authorised to write in there.
There is a nice diagram of a pitot/static probe and a description of how it works, despite the fact that the A330 has pitot probes, and separate static ports. The guy that wrote it should have twigged it when he wrote 3 pitot/static probes and 8 ADMs.

[augustusjeremy]

Transcription: "In relation to the Rudder Travel Limiter (RTL) if the violent storm theory holds then it is probably as a result of structural failure due to massive yawing forces induced by turbulence. The F/CTL RUD TRVL LIM FAULT message has been generated due to the NAV ADR DISAGREE message and NOT due to a fault in the Rudder Travel Limiter itself NOR due to a failure/separation of the rudder. If the problem lay in the unit itself, a F/CTL RUD TRVL LIM 1 / (2) FAULT would appeaer. This is due to the Rudder Travel Limiter requiring an airspeed input from the ADR’s to function properly."

[vapilot2004]

This information below was just posted 7 hours ago and thought it might be of useful information to a few experts here.

Engineer decodes Air France Flight 447 emergency messages (http://blog.seattlepi.com/aerospace/archives/170669.asp?source=mypi)



@NSXTASY:

From the link:
Then the rudder exceeds the limits of normal flight.


This is utter rubbish. The message sent by the central maintenance computer was that the limiter was flagging itself - most likely due to the lack of airspeed data (ADIRUs) and nothing whatever about any rudder limits that had been reached as this 'engineer' suggests.

@727GM

Once again we have no indication that any of the ACARS messages were
related to a loss of VS. To say otherwise is not helping this thread. The
aircraft in question would not have suddenly started wagging its tail for lack
of ADIRUs, nor has there been any demonstrated sane reasoning shown so
far that would support our PF to have suddenly had an urge to start
stomping away at his rudder pedals.

[ELAC]

ELAC,
Correct me if I misunderstand you, but it seems to me that you're implying the AF crew did deviate from track? Doesn't the evidence (comms from the crew, ACARS transmissions, location of wreckage and debris) indicate that AF447 stayed on track and flew into, or found itself in, a major storm cell?
Rockhound

@Rockhound

I'm implying that we don't really know what path they took after their report at INTOL. To my knowledge the ACARS transmissions don't include location and the position of debris found in the ocean means very little with respect to the specific track flown, particularly after days of drift.

Regarding communications, HF radio in oceanic airspace is not like you experience with VHF over land. At times atmospheric conditions can make HF communication impossible and it varies from place to place. Just because comms were good at the last position report doesn't mean they'll work 20 minutes later. If deviating without a clearance oceanic procedures would have required a broadcast on 121.5/123.45 but there is no record of anyone having heard one. Again, that doesn't mean that a broadcast wasn't made (severe electrical storms can interfere with VHF reception). So, that a request to deviate wasn't received does not prove that a request wasn't transmitted or that a deviation from track didn't occur.

Until those facts are known it's not really possible to conclude whether they attempted to deviate, and if so by how much, or whether they flew directly through the MCS shown in the satellite image or not.

ELAC

[WNcommuter]

ELAC wrote:

Until those facts are known it's not really possible to conclude whether they attempted to deviate, and if so by how much, or whether they flew directly through the MCS shown in the satellite image or not.

Point taken and much appreciated. The mystery deepens.

Did we ever confirm whether or not the crew sent a text message about turbulence? I'm confused by recent posts on that subject.

[A33Zab]

?? asked this question: (deleted)?


If speed indication fails (for whatever reason) then rudder limitation stops. Am I right? if that's the case, how on earth (on air) a pilot would know how much rudder could apply without breaking it? Even more, in FBW a/cs, where pumps and fluids can creat a LOT of force, wouldn't this become super critical? Same question applies to the case of using "alternate law".



Because besides the RTLU (Rudder Travel Limiter) there is also a PTLU (Pedal Travel Limiter) - limiting mech(cable) pedal input to rudder servo jacks - in this 'classic' Yaw control system.

In the 'Enhanced' version there is no mech(cable) backup so also no RTLU/PTLU.
Art feel and Trim is directly on Pedals by a PFTU.

RTLU/PTLU in this 'classic' version and also PFTU 'in the enhanced version' are driven by SEC1 (SEC2 as backup) an this has nothing to do with - LAW- configuration.

Rudder Travel Limiter is mounted on the VS rear spar above the upper servo jack (so is retrieved within the VS and last position soon to be known by the investigators)

The Pedal Travel Limiter however is mounted in the THS compartment.

A330 tech.

[FrequentSLF]

PJ2

has taught passengers to expect and demand $1.49 fares in exchange for on-time,

I always read your post with great attention because are part of the few ones with some meaning on most threads in PPRuNe.
However let me disagree on the PAX demanding $1.49...they are offered such fares and they will take it, note that I am not a LCC PAX therefore my mindset on the topic might be bias.
What disturb me is inferring that low fares are lowering the safety standards....where are the Control Boards?
Could be that competition have brought to the flight systems ways to save costs and become more efficient? Following your rational we could also state that the special fares for the crews and employees of an airline are the cause of the lower safety standards.
Thanks for your great contribution
FSLF

[Config Full]

http://img229.imageshack.us/img229/3378/94605963.jpghttp://www.fab.mil.br/portal/voo447/FOTOS/loc_fotos/foto_1.jpg

[pax2908]

Apologies again if this is silly or off-topic.

There is a possible chain of events, being discussed, that starts with the failure of the Pitot probes. Does this imply that at least two probes must have failed (almost) simultaneously? I saw mentioned "EFCS PROBE 1+2/2+3/1+3" sitting next to "F/CTL RUD TRVL LIMIT FAULT". How exactly is it determined if a probe is failing: is it some low-level status related to the probe itself (heating?); or is it determined e.g. by comparison with the other (one or two) probes? Also, I assume that power for the 3 Pitot heaters comes also from different buses?

[LUALBA]

FYI again:


As reported in AIT reference "AF447 Issue 3 June 8th 2009", there are 3 standards of pitot probes in
service on the A330/A340 family aircraft:

- Thales (ex Sextant) PN C16195AA and PN C16195BA
- Goodrich (Rosemount) PN 0851HL

It is reminded that the 'BA' standard probe was made available to address low altitude water ingress
events that generated a number of RTO on the A320 family program.

AF447 aircraft was equipped with Pitot PN C16195AA.

The intense speculation regarding these pitot probes has led many Operators to contact Thales or
Airbus to:

- request an immediate replacement of the Thales 'AA' probes with 'BA' (Service Bulletins A330-34-
3206, A340-34-4200, A340-34-5068)

- report recent and past (previously unreported) events of Unreliable airspeed.

These events, after analysis and confirmation, will allow to determine if any corrective action is
warranted by the findings.

In this context, all Operators, equipped with Goodrich (Rosemount) or Thales (Sextant) pitot probes,
are requested to report all confirmed in-flight Unreliable airspeed events.


2/ TYPICAL SIGNATURE OF UNRELIABLE AIRSPEED

To be sure that Unreliable airspeed events are correctly identified, please report events corresponding
to the criteria as follows:

- Crew report indicates loss or discrepant IAS (Indicated Airspeed) on CAPT and/or F/O PFD and/or
Standby Airspeed indicator (ISIS).

- Typical ECAM Warnings were seen:

NAV ADR DISAGREE
NAV IAS DISCREPANCY
F/CTL ALTN LAW
F/CTL RUD TRV LIM 1(2) FAULT
AUTO FLT AP OFF
AUTO FLT A/THR OFF
STALL WARNING (audio call-out)
AUTO FLT REAC W/S DET FAULT


- Fault Message "PROBE-PITOT 1+2/2+3/1+3" was possibly also seen.

[Safety Concerns]

Any probe heating issue would have been flagged by the PHC's. (PROBE HEAT CONTROLLERS) They are able to determine whether a probe is being heated or not.

Any issue with probe heat and you would have a different selection of messages although there would be some overlap.

The probes have their own independent PHC.

Manual autopilot disconnects are logged on acars as well just in case some haven't seen post #915

[DC-ATE]

A lot of talk about the rudder on AF447. I asked this in the Tech Forum but got no reply. What indication is given the pilot when they are in other than 'Normal Law' on an Airbus as to how much rudder to apply or NOT to apply, if needed, to keep the rudder attached to the airframe?

Is the Airbus of such a design that one needs to accually use the rudder in flight, even in turbulence? I only flew Lockheed, Douglas, and Boeing aircraft (Transport-wise), but don't recall ever using the rudder except on the ground. Oh, maybe during crosswind take-offs and landings, but NEVER enough to cause any kind of problem, with or without boost. Thoughts anyone?

[sumi]

Interesting little detail on the picture lifting the fin onboard: The top of the fin / rudder seems intact, but only one static discharger remains attached. At least 3 are missing.

Of course, they could have gone during impact (but looks not damaged), or during handling by the Brazilian team in the water, or due to lightning...

[Config Full]

DC-ATE,

My thoughts are that AA587 cannot be compared with AF447 with regard to the rudder use. AA587 was flown on a A300-600 and according to the NTSB investigation this type of aircraft, in comparison to others, has the lightest pedal forces as well as among the shortest pedal travel, making it harder to gauge the right force applied to them.
To my knowledge no Airbus A330/A340 have reported issues similar to those that eventually brought down AA587.
Instead I have read a report by a AF Concorde pilot who said that in its early tests the A300 displayed weaknesses in the rudder, and I always wondered whether that was somewhat related to AA587. But nothing with the A330/340. And there is no evidence to tell here at this time. Simply wait for the investigation.
If I find the AF pilot quote I'll post it here.

[Desertia]

:: FAB - Força Aérea Brasileira :: (http://www.fab.mil.br/portal/capa/index.php?page=voo447)

[sumi]

to chefrp:

That's unlikely but possible. Static dischargers are here to discharge static electricity, and when you get a lightning strike (can be anywhere on the fuselage, sometimes one or more "burn away", that's what they are installed for. So this could be a sign of (very) intense lightning action, if the 3 were gone due to lightning. But as I mentioned above, could also be during the water-impact or during handling later.

[Fly-by-Wife]

One very obvious difference between AA587 and AF447 that I haven't seen mentioned is that in the former, the rudder and VS had separated at some point prior to discovery, while in the latter the entire assembly has been recovered intact.

Significant? I don't know.

FBW

[DorianB]

09/06/2009 - 10h49
Press Release- English
PRESS RELEASE 21

The Brazilian Navy Command and Aeronautical Command inform that, from the beginning of the search until now, the total of bodies recovered from the ocean is 24, all now aboard Brazilian ships.
The last eight bodies recovered, in a joint effort of the Brazilian Navy and the French Navy, will be in due time be sent to Fernando de Noronha, where they will receive initial preparation and afterward transport by plane to the city of Recife (PE).
The Frigate Constituição is around 400 kilometers from the Archipelago of Fernando de Noronha, with the 16 bodies previously rescued. The meteorological conditions have not interfered with the search and rescue operation this day, still there are meteorological formations that indicate bad weather in the proximity of the Archipelago.
Currently the Operation counts with 255 military personnel from the Brazilian Air Force, moved to Natal (RN), Recife and Fernando de Noronha (PE), and 14 aircraft, with 12 being Brazilian Air Force and 2 from France. The H-34 helicopter (Super Puma - FAB) flew from Natal to Fernando de Noronha, in order to directly support the rescue operations.
The Brazilian Navy now has 570 military personnel on board the ships. The Patrol Boat Guaíba substituted the Patrol Boat Grajaú that returns to Natal (RN) to resupply. Thus, five Brazilian Navy ships and one French Navy Frigate, continue in the area of operation.
The search and rescue missions continue, without interruption, and are concentrated on the areas where the bodies were located. The search for other clusters of wreckage continues to be carried out by the R-99 aircraft, and during the night, visual search aircraft work on the transport of supplies to Fernando de Noronha.

NAVAL SOCIAL COMMUNICATION CENTER
AERONAUTICAL SOCIAL COMMUNICATION CENTER

[pax2908]

Safety Concerns,

Thanks. I understand/extrapolate from your answer that the PHCs are powered independently; and also that you expect to see a specific message if there is any problem including the loss of power. So then what could cause all 3 to go at once (IF that's what happened).

I suppose there is still a possibility that the recorded list of events is incomplete and some earlier items did not go through for some reason?
Somebody reading these logs regularly, could perhaps tell, what is the max. number of messages per second one could expect?

[RobertS975]

Does anyone have any info as the the location where the VS was found in comparison to the other debris and victims that have been discovered? If the VS was found many kms away from the other debris, that would imply that it separated from the rest of the aircraft at some altitude rather than by surface impact.

[protectthehornet]

I thnk the coffin corner business is part of the airspeed problems. it would have been easy enough to stumble a bit closer to the regime called coffin corner if you are way off your airspeed.

stall speed is changed a bit under heavy G loading...and we don't yet know what the turbulence did to G loading on a plane that might have been flying too slow due to poor airspeed information.

if the airspeed was off 35 knots (unknown) and the flight envelope was 25 knots on either side...one could easily stumble.

I want to make it clear that in normal operation with normal instruments etc. FL350 was probably a normal choice.

[DorianB]

Somewhere care to translate? Their English version isn't up yet:

09/06/2009 - 11h52
Nota 22 - 09.06.09
INFORMAÇÕES SOBRE AS BUSCAS DO VOO 447 DA AIR FRANCE

O Comando da Marinha e o Comando da Aeronáutica informam que a Fragata Constituição chegou às 6h15 (horário de Brasília), a um ponto distante 55 quilômetros a nordeste do Arquipélago de Fernando de Noronha. Nesta manhã, um Helicóptero H-60 Blackhawk e um H-34 Super Puma, ambos da Força Aérea Brasileira (FAB), decolaram para recolher os primeiros 16 corpos a bordo da fragata.

Após a liberação em Fernando de Noronha, uma vez cumprida a atividade pericial inicial pela Polícia Federal, os corpos serão transportados para Recife em uma aeronave C-130 da Força Aérea Brasileira. O tempo estimado até Recife é de uma hora.

Uma linha de instabilidade na região de Fernando de Noronha atrasou a operação de transporte de corpos e poderá limitar os vôos que partem do Arquipélago ao longo do dia. No entanto, as condições meteorológicas na área de busca não interferem nas operações em andamento.

Nesta Manhã, foram resgatados mais quatro corpos pela Fragata Bosísio, da Marinha do Brasil, o que eleva para 28 o número total de corpos resgatados até o presente momento.

O efetivo e os meios empregados na missão permanecem sem alteração. As ações de busca e resgate continuarão de forma ininterrupta, concentradas nos pontos onde foram localizados os corpos.

CENTRO DE COMUNICAÇÃO SOCIAL DA MARINHA
CENTRO DE COMUNICAÇÃO SOCIAL DA AERONÁUTICA

[22 Degree Halo]

09/06/2009 - 11h52
Note 22 - 09:06:09
INFORMATION ON SEARCHES OF THE AIR FRANCE FLIGHT 447

The Navy Command of the Air Command and the Frigate Constitution report that reached the 6:15 a.m. (schedule of Brasília), at a point distant 55 kilometers northeast of the archipelago of Fernando de Noronha. This morning, a helicopter H-60 Blackhawk and a H-34 Super Puma, both the Brazilian Air Force (FAB), off to collect the first 16 bodies on board the frigate.

After the release in Fernando de Noronha, once met the expert initial activity by the federal police, the bodies will be transported to Recife in a C-130 aircraft of the Brazilian Air Force. The estimated time to reef is an hour.

A line of instability in the region of Fernando de Noronha delayed the operation of transporting bodies and may limit the flights leaving the archipelago throughout the day. However, the weather in the area of search will not interfere in the operations in progress.

This morning, four more bodies were recovered by Frigate Bosísio, the Brazilian Navy, which brings to 28 the total number of bodies recovered so far.

The effective and the means employed in the mission remains unchanged. The actions of search and rescue will continue on an ongoing, concentrated in places where the bodies were located.

MEDIA CENTER OF MARINE

Text and Web - Google Translate (http://translate.google.com/translate_t)#

[SPA83]

http://nsa08.casimages.com/img/2009/06/09/090609101258388563.jpg (http://www.casimages.com)

[ClippedCub]

Would like to point out that vertical leading edge is in fantastic shape. Not even the paint is chipped. This would rule out an intense hail encounter. So the radome debris impacting the pitot tubes can be ruled out.

[Trash_Hauler]

Well ClippedCub, I would offer that from a DISTANCE in a small(ish) photo it looks to be in good nick... It's way too early to rule anything out!

[Lost in Saigon]

Cropped and enhanced from: FORÇA AÉREA BRASILEIRA - Asas de um povo soberano (http://www.fab.mil.br/portal/voo447/fotos.php)

http://i2.photobucket.com/albums/y17/msowsun/Airline/af447_tail1aa.jpg

[727gm]

@727GM
Once again we have no indication that any of the ACARS messages were
related to a loss of VS. To say otherwise is not helping this thread. The
aircraft in question would not have suddenly started wagging its tail for lack
of ADIRUs, nor has there been any demonstrated sane reasoning shown so
far that would support our PF to have suddenly had an urge to start
stomping away at his rudder pedals.

Not saying ACARS messages are related to loss of VS.

Not saying anything about ADIRU's, or sudden wagging of tail.

Not saying anything about anyone "stomping" on anything.

Doesn't help thread to try to put words in other poster's mouths.

[Flying Frenchman 2000]

I am not a great fan of these tabloid style threads,

But when I see dead colleagues being criticized, I feel I have to react.

441A, Who are you to judge without any knowledge of what happened?

Have a little respect for the victims and let the pros do their work.

[Config Full]

DC-ATE,

In alternate law the damper function is limited to +/- 4° rudder in CONF 0 and +/- 15° in other configuration, while the maximum rudder angle will be locked at +/- 10° in CONF 0. (Its full travel value is regained with the slats extended.)

[ClippedCub]

Trash_Hauler, with all due respect, I would postulate that smallish pictures can depict significant hail damage from a distance,

(Edit; thanks Saigon, Photo two doors down.)

in poor light.

Granted, the vert leading edge is composite, so dents wouldn't occur, but significant hail would have scarred/chipped the paint.

[Flyinheavy]

There is much talk about it here. Could anybody explain why the report of the Air Caraibe incidents of lst year August & September states the following:

Conrol Alternate Law:

la valeur maximale du debattement est gelee a 10°

means the value of max rudder travel is locked at 10°

The ACARS msg refers to exactly that situation, they were at Controls 'Altn Law'. I think those pilots would need no other indication, they would know what Altn Law means. Just for those who keep asking, if there is any indication.

Let me say more, I am before retirement, I have been flying with a lot bright young pilots over the years, who did a very good job. Insinuating that todays young pilots are less trained or do not have the experience required is an assumption which should not be generalized. Just my oppinion...

[Lost in Saigon]

Trash_Hauler, with all due respect, I would postulate that smallish pictures can depict significant hail damage from a distance, in poor light.

Granted, the vert leading edge is composite, so dents wouldn't occur, but significant hail would have scarred/chipped the paint.


Snopes doesn't let you hotlink their photos but here it is:



http://i2.photobucket.com/albums/y17/msowsun/Airline/af447_hail.jpg

[etsd0001]

The NY A300 fin failure was because the rudder was cycled back & forth without a pause and the forces just multiplied with each reversal

[captainflame]

Let's put this one to rest once and for all ! :ok:

The message F/CTL RUD TRV LIM Fault is justified by the loss of the ADR data.

As said previously in this thread, the rudder travel is then limited to 10 degrees and full deflection is only recovered at slats extension.

An Air Caraibe A330 incident report is circulating (in french) which describes a (survived) event sounding very similar to the AF447 event.

In the air Caraibe event (which I will try to find in english)....icing over of the Ptot probes and TAT probe at FL 350, in transoceanic equatorial WX, with severe turbulence, occured.
The following ECAM messages, flags and system reversions are consistent with the ones reported ont the AF447 ACARS report.

As decribed earlier in this thread, the TAT increase from -14 to -5 degrees typical of an iced up probe measuring the ice temperature instead of the Ram Air.
At some point in this event the CAS, MACH and ALT go respectively from 274Kts, M0.80 and FL350 to 85kts :eek:, M0.26 and FL347.

At the same time the cascade of ECAM warnings and cautions include NAV ADR Disagree, F/CTL ALT LAW, F/CTL RUD TRV LIM, ENG EPR mode faults (different engines there), Speed Flags on PFDs, loss of FDs, A/THR, etc....Including at some point STALL STALL audio warning (no protection in ALT LAW) :{

Summarily, the PF flew "pitch and power" with PNF on QRH unreliable speed indication, disregarding the STALL warning and using backup info of GPS Ground speed and Altitude (ND and FMGC).

Air Caraibe has modified all the 330 probes earlier this year.

Again, the Air caraibe report is VERY similar to what is now known of the AF447 troubles. (Weather, turbulence, airspeed data problems)

[eagle21]

etesting2000There had been some talk earlier that we as humans did not have the capability to search to the depths where this incident occured. This has recently changed. Woods Hole Oceanagraphic Institute demonstrated 6.8 Miles at the bottom of the Mariana Trench on May 31, 2009.

link to press release

News Release : Hybrid Remotely Operated Vehicle “Nereus” Reaches Deepest Part of the Ocean : Woods Hole Oceanographic Institution

Thanks for the link, very informative. Let's concentrate in recoverig the FDR/CVR instead of speculating so much about things we do not know.

Cost should not play a part in a possible recovery mission , it has not been made public any plans about having suitable deep sea exploration vehicles on standby in the area not to waste time should the boxes be located towars the end of their battery life.
How fustrating would it be to locate the pinger and then by the time the exploration vehicles arrive not to be able to find the boxes due to the drift caused by currents?

[Flyinheavy]

@captainflame:

That's exactly what I mean, the link had been posted yesterday by Svarin.

What caught my attention was, that they had contraversial documentation regarding to follow or not a possible Stall Warning. It's been the correct decision of the Cpt to NOT FOLLOW. The ACA crew was avoiding a CB flying in a Cirrus. Imagine this scenario surrounded by CBs at night.............

[cesarnc]

French ship Pourquoi Pas left Cape Verde this Tuesday to help in the search for A330's black boxes.

The ship carries three submarine robots, two of which are able to dive down to 6,000m. The other is capable of operating for 12 hours, navigating in triangles and is able to get signs and point towards the exact location of the black boxes, according to the French Embassy in Praia, Cape Verde's capital.

Translated from Brazilian news website Terra.

[KC135777]

curious.....do the A330s have AOA vanes?

If so, do they have AOA indicators on the pilot's instrumentation?

If so, does the data get interpreted by the ADC, and then transmitted/displayed on the indicator? or another means?

Thanks, KC135777

ps...sorry if this has been discussed already.....it's just too long to go through.

[etsd0001]

Originally posted by sumi (reply 940)

Static dischargers are here to discharge static electricity, and when you get a lightning strike (can be anywhere on the fuselage, sometimes one or more "burn away", that's what they are installed for.

They are not installed for that purpose -

Airbus MM -
During flight the aircraft can become charged with static electricity. If the discharge of this static electricity is not controlled, it can cause interference in the communications and navigation systems. Static dischargers are installed on the aircraft to decrease the interference.

Boeing MM
Static dischargers are installed on the airplane to reduce radio receiver interference. This interference is caused by a corona discharge emitted from the airplane surfaces as a result of precipitation static and engine charging. Precipitation static results from an electric charge accumulated by the airplane striking charged air and moisture particles.

Static usually discharges at the wing and tail extremities and is coupled into the radio receiver antennas. The static dischargers are designed to discharge the static at points which are a critical length away from the wing and tail extremities where there is little or no coupling of the static into the radio receiver antennas.

[mm43]

Transition from air density at sea level to the density of salt water results in an increase of the mechanical leverage on the VS by a factor of 742.

Basic photographic evidence seen so far points to a clean parting from the airframe structure on the forward end of the VS and compression damage on the aft end, consistent with a high speed entry of the a/c.

mm43

[BigHitDH]

Interesting that the shot of the tail being hoisted from the ocean shows quite clearly 2 white box structures attached to the lugs. There should be three of these, but I can't tell from the photos if it's the fore or aft one that's missing.

[Lost in Saigon]

I feel that this thread may need a re-focus. Many of the comments seem to be bogged-down with minutiae....

Why would an experienced crew venture (with presumably expertise and w/x radar into a 'no-go' w/x storm CB soup such as this?).

I was trained to avoid this sort of weather by many miles. Experience taught me via various incidents that 20nm (min. trained) avoidance from CB tropical should actually be 100nm avoidance.....Full Stop! AAAC (Avoid at all costs).

If fuel is a worry; divert/turn back.

The weather indicated and discussed fully in all manner of prior posts was not; repeat NOT an area where any passenger aircraft should even have attempted to go anywhere near. Full Stop!


There is no proof that they went anywhere near a CB. Only speculation based on their planned route. They could have deviated a hundred miles around the nasty weather then crashed as they were returning to course.

Other crews transited that same area and there is no reason to expect that AF447 would have any trouble on the same route.

Be patient and deal with the known facts.

[TvB]

"There should be three of these, but I can't tell from the photos if it's the fore or aft one that's missing."

It is the fore part which is missing. The middle and aft lugs seem to be there and the bolts still in place.

[PJ2]

A detail of the "boxes" referenced earlier. Given access to the AMM, I suspect these are the middle and aft attach points for the vertical stabilizer. In fact, one can observe a hole where the front attach point would be - we have seen this kind of failure mode in the AA587 lugs.

These structures attached to the VS would be within the tail structure itself, further attached to the fuselage structure. The "ears" and "lugs" with which some are familiar here from the AA587 accident photographs can be clearly seen attached to these box structures, except the front one, I surmise.

The "ears" which form a part of the CFRP structure of the VS remain intact. Whatever separated the VS from the tail structure had to be strong enough to tear this entire structure away from the fuselage section itself. We still do not know whether the main loads were lateral or fore/aft.


http://i277.photobucket.com/albums/kk76/batcave777/VertStabBaseDetail.jpg

[scarebus03]

But why did the following IB aircraft divert 56kms to avoid the same storm?

Don't shoot the messenger, it's from the Spanish press three days ago,

Brgds
SB03

[BigHitDH]

TvB, PJ2,

Thanks for the clarification, that's what I suspected.

One would have to assume if the tail did part company with rest of the airframe while in flight, this would have created one hell of a hole.

As far as I am aware, all of these lugs are aft of the pressure bulkhead?

[TvB]

BigHitDH!

affirm. they are aft the rear pressure bulkhead which - I believe with the new A330's is from composites too, such as the tailcone and tail section... Pls. correct me if I'm wrong.

[ankh]

The crewed submersible that will be used:
Nautile (http://www.ifremer.fr/fleet/systemes_sm/engins/nautile.htm)

The remotely operated vehicle that will be used:
Victor 6000 (http://www.ifremer.fr/flotte/systemes_sm/engins/victor.htm)

The researcher who answered some questions about this equipment, detection ranges, etc.
Air France 447 | Deep Sea News (http://deepseanews.com/2009/06/air-france-447/)

[eagle21]

scarebus03But why did the following IB aircraft divert 56kms to avoid the same storm?


BS! You don't know what information was available to the AF crew, or their circunstances!

Is good that IB avoided this WX, let's find out why AF didn't and whether this had an impact on the outcome.

Wait for the FDR\CVR , until them we should all pay respect to our colleagues who ended up in the ocean.

[BigHitDH]

Thanks TvB.

Scarebus,

But why did the following IB aircraft divert 56kms to avoid the same storm?

Don't shoot the messenger, it's from the Spanish press three days ago,

I'll avoid mentioning the loaded name...

There is no evidence to suggest that they didn't divert around weather. Their track may be vastly different from another aircraft 30 mins ahead/behind, the weather that night was clearly very dynamic and changing.

[PJ2]

BHD;
As far as I am aware, all of these lugs are aft of the pressure bulkhead?
Yes, well aft. This tells us nothing of the condition of the pressure bulkhead but permits some thought only, towards the rest of the structure ahead of the VS to the area overhead the pressure bulkhead. Because we cannot know about the rest of the structure, nor does this tell us nothing about the DFDR/CVR location or that it remained fastened to the structure.

What is on my mind I will now confess, is, what is the nature of the forces capable of doing this kind of damage? I find it difficult to accept that any rudder deflection in and of itself, could do this. Such forces may and will be calculated as a matter of engineering sleuthing as can the mode of failure through the aforementioned tell-tale marks, bent/torn metal, etc so we can know at least in terms of "foot-pounds" what it takes to uproot the VS thus.
this would have created one hell of a hole.
Yes - an examination of this area either by drawings or physical inspection of other 330's may tell us what else "left" with the VS, pulled by piping/cabling/wiring/ancilliary structure etc - pure conjecture but at least "reading" the trace.

[DorianB]

Força Aérea Brasileira is reporting a max distance of 85km between retrieved bodies. 46km radius (92km max distance) for 'large piece' debris.

I'm no expert in ocean currents...but that seems pretty far apart for an intact water entry...




http://i635.photobucket.com/albums/uu79/DorianBanks/slide2.jpg



http://i635.photobucket.com/albums/uu79/DorianBanks/slide1.jpg


(edited to add images)

[w1pf]

this is probably a noise post.. but..

AF447 found itself in a certain space and time - and we need to understand the information and decisions that led to that space and time.. and what the conditions were at that space and time.

AF447, craft and crew, then had to deal with what they were dealt - and we need to understand what both did, what the results were, and why.

That's what needs to happen for the future of aviation and closure for the deceased. The rest is fluff.

Pilots don't intentionally do 'stupid' things, engineers don't intentionally design 'fragile' aircraft, and companies don't intentionally sell 'fragile' aircraft... The crew was experienced, the aircraft and the airline have good records. Let's back off on the character assassinations and pet theories and try to understand what clues we have.

As you were,
...tom

[spannerhead]

Here's my thoughts on the photographic evidence. The forward mount of the VS appears to be missing and the aft mount appears to have torn away the supporting structure within the fuselage. The forward mount may have failed (either in controlled flight through turbulance or during the uncontrolled decent) tilting the VS rearwards (causing the damage to the lower part of the rudder on contact with the top of the APU bay). The VS would then be ripped from the aft mount area and rather like a sycamore seed falling from a tree, gently (reletively speaking) 'helecoptered' it's way to earth. This would account for the small amount of damage to the VS/rudder structure.

[ClippedCub]

We still do not know whether the main loads were lateral or fore/aft.

There is a major difference between this damage and AA587, all of the composite tabs on the vertical failed. Here, most of the attachment fittings, I would guess both sides, departed from the empennage, with some cross-over structure. And the crossover structure is sans empannage skin. Also, the rudder on AA587 was substantially damaged and removed from the vertical. Were the vertical attachment tabs redesigned to be stronger after the AA587 accident.

If the recovery ships rushed to the site of the first body recovery, then this would imply the vertical was in the same general area. (There are some maps on the Brazil site, but couldn't bring them up.)

Can visualize a case of inverted entry into the water where the vertical sliced through the surface, and the empennage structure was ripped away from the submerged vertical.

We need a structural engineer to chime in.

[Will Fraser]

PJ2

Fairly certain I see three attach/systems. the forward hole (missing the pin) is 'shading' a bulkhead cap similar to the most aft structure. All three towers seem present, though what would be the port side of the forward carriage is in darkness. The fairing at the emp/VS mate is gone, uncovering the primer in the shape of the fillet. (That may help some locate the assembly in the above picture of the a/c)

??

[BigHitDH]

PJ2,

an examination of this area either by drawings or physical inspection of other 330's may tell us what else "left" with the VS, pulled by piping/cabling/wiring/ancilliary structure etc - pure conjecture but at least "reading" the trace.

Agreed. It would be a reasonable assumption that disruption of the airframe at this scale and location would have some impact on the structure of the THS also. In fact, could those white box structures be directly connected to the spar structure of the THS. Any A330/340 mechanics care to offer an opinion? PJ2, you appear to have access to the A330 AMM, is there any info in there?

[HarryMann]

Força Aérea Brasileira is reporting a max distance of 85km between retrieved bodies. 46km radius (92km max distance) for 'large piece' debris.

I'm no expert in ocean currents...but that seems pretty far apart for an intact water entry..

Many thanks for that... tend to agree, but noe expert either.

The missing information is where in that circle the fin (VS) was found!

[SaturnV]

DorianB, the number of bodies recovered is now reported as 41. As bodies are identified, they will be matched to seat assignments, and the coordinates where they were recovered.

If clusters of bodies are found up to 85 km apart, that would seem to be a greater distance than what might be expected from an intact aircraft crashing into the sea.

[Backoffice]

Returning to the subject of pitot tubes.
The manufacturers, I believe in this case Thales, will probably be following a pattern that has been used successfully for years.
One must then ask, why are the A330/340 subject to contamination, if that’s the right word. Could it be their location ? i.e. high/low pressure in the wrong place preventing the drain from functioning correctly.

[Lost in Saigon]

But why did the following IB aircraft divert 56kms to avoid the same storm?

Don't shoot the messenger, it's from the Spanish press three days ago,

How do you know that AF447 did not divert the same 56kms?

Please explain how you, or anyone else would know this......

[ClippedCub]

Fairly certain I see three attach/systems. the forward hole (missing the pin) is 'shading' a bulkhead cap similar to the most aft structure. All three towers seem present, though what would be the port side of the forward carriage is in darkness. The fairing at the emp/VS mate is gone, uncovering the primer in the shape of the fillet. (That may help some locate the assembly in the above picture of the a/c)


Excellent point. The forward 'hole' is in the wrong location in the photo. It would be lined up with the other two, and located more forward. The attached, forward empennage structure is creating the illusion, or shadowing, looking like a hole. Also notice that tab transitions into the vertical box have a radius, but the forward does not. We're looking at blocking from another piece of attached structure.

I'm beginning to think the vertical didn't separate in flight. If it did, it was part of a package, including the empennage. Experience with AA587 would make us jump to that conclusion, (guilty as charged in the beginning), but there are too many dissimilarities, e.g., failure characteristic, intact rudder.

[Mad (Flt) Scientist]

Returning to the subject of pitot tubes.
The manufacturers, I believe in this case Thales, will probably be following a pattern that has been used successfully for years.
One must then ask, why are the A330/340 subject to contamination, if that’s the right word. Could it be their location ? i.e. high/low pressure in the wrong place preventing the drain from functioning correctly.

There's nothing particularly special about pitot probes icing up - if thats what happened. They all can be iced up, and are all heated accordingly. So any extreme weather conditions outside the qualification of the probes could ice up ANY probe design.

There's nothing special about the probes being damaged by hail - if THAT is what happened. Hail doesn't play favourites between manufacturers.

There's nothing special about probes ingesting water - many (all?) pitot/static systems have drain lines to allow moisture to be removed. Again, extreme weather conditions ...

The foregoing all to say that there may not be anything special about the probe design or location.

Without looking into the SB about these probes in detail one cannot say whether the specific issue that its supposed to correct is a likely, unlikely, or negligible factor in any possible probe problems. it's suspicious that an aircraft with possibly suspect probes had a problem which might relate to the probes. But I'd be loathe to make the direct link. After all, if it were a serious deficiency then I'd have expected stronger action by Sb and/or AD AND many more issues in service.

[PJ2]

Will Fraser;
Fairly certain I see three attach/systems. the forward hole (missing the pin) is 'shading' a bulkhead cap similar to the most aft structure. All three towers seem present, though what would be the port side of the forward carriage is in darkness.
'k, I can take a further look by bringing the shadows up a bit, thanks. We'll know soon enough I'm sure.

BigHitDH;
I have access to a 340/330 AMM and tried for a while to find drawings of these structures but ran out of time. The AMM is not the easiest nor friendliest document to navigate in so it is very time-consuming.

I strongly suspect the boxes are near or perhaps part of the THS structure but can't say so.

[eqd]

SaturnV (http://www.pprune.org/members/29239-saturnv) @1000,

It's theoretically possible that two piles of objects separated by only a few hundred meters could be in diverging current streams (especially as the North and South equatorial currents meet and diverge in that area of the Atlantic). 85 km over several days is less than 1 km/h relative difference velocity.

[BigHitDH]

PJ2,

Yep, been trawling through some stuff myself, I appreciate it's not the easiest.

ClippedCub, others.

I can't make out what you describe in the picture, I see no box forward of the middle one. I can't see it in the image below either.

http://img229.imageshack.us/img229/3378/94605963.jpg

Can you elaborate? Sorry if I'm missing the obvious!

[Backoffice]

Thanks BigHitDH and Mad Scientist.
My doubts were raised by the comments that the replacement tubes may not completely cure the problem, implying (to me) that Airbus might be aware of another issue, purely conjecture on my part.

[PJ2]

ttcse;
Don't forget the vertical possibility, say from impact while in a spin or stall.
With respect, transport category aircraft do not "spin". Cubs, 172s and light twins "spin". The NTSB animation of the Colgan accident is as close to "spin" as an airliner might get - more like a spiral dive quickly achieving very high speed with high nose-down pitch attitudes and requiring significant altitude to recover, if at all.

While transport aircraft stall as has been amply demonstrated of late, the results are almost always catastrophic, the exception being the slow-speed Amsterdam accident, ergo, an intact vertical stabilizer with essentially-unscathed internal mounting structures, would not obtain in such a vertical accident.

Any high-speed impact with water is the same as hitting a rock face thus the exhibited wreckage distribution pattern and disintegration would be like SW111 if anyone is familiar with that investigation, (I am, but only very much on the periphery). With the greatest of respect for the victims and families and apologies for a terribly indelicate observation, the condition of the remains found thus far almost certainly indicates an in-flight breakup at some point during the accident sequence.

[ClippedCub]

Thanks for the new perspective BigHitDH, your photo indicates a lack of forward attachedstructure, which is helpful. Go back a couple of pages for PJ2's photo I was describing. Don't think that forward 'hole' is a hole in PJ2's photo. Customary attachment is to line the holes up, as shown below in the A310 photo, (also shows relation of rear attachment to the horizontal, for the A310 anyway),

http://www.bst.gc.ca/eng/rapports-reports/aviation/2005/a05f0047/images/a05f0047_photo_2.jpg

The missing rudder was due to a flutter, in the photo case, due to a fault in the rudder structure.

[SaturnV]

egd, theoretically yes.

In Air India 182, they recovered 131 bodies of the 329 on-board. I do not know the radius of the area from which the bodies were recovered, but it may be in the accident investigation report.

From the post-mortems (on Wiki), eight of the recovered bodies had been ejected from the aircraft before it crashed. Other causes of death (at least contributory) included explosive decompression (those sitting near windows), hypoxia, asphxia (one child and one infant), vertical force injury, and three who died by drowning.

[HarryMann]

Hopefully they won't blame this on the pilot too.

Now don't be silly... The PIC of 587 overcontrolled and drove the yaw oscillation to a destructive degree - FACT

Not a good or useful contribution IMHO :ugh:

[PJ2]

ttcse;

Thanks - I had forgotten that photo - but we cannot see a damage pattern. PJ2

[mseyfang]

eqd stated:

It's theoretically possible that two piles of objects separated by only a few hundred meters could be in diverging current streams (especially as the North and South equatorial currents meet and diverge in that area of the Atlantic). 85 km over several days is less than 1 km/h relative difference velocity.

This seems logical to me; it is a small difference in velocities given the times involved. Unless an expert weighs in with some knowledge of oceanic drift patterns, I would be cautious in reading too much into these distances. In addition to ocean currents, certain objects may be affected by surface winds as well. One would expect a difference in motion between objects which are partially above the water (and thus exposed to wind) versus objects that are more or less level with the surface.

[PJ2]

jmig29;
My experience tells me something very terrible happenned in cruise, that did not give the crew any reaction timing, which leads me to think maybe other "non spoken" aspects may have to be considered. Looks to me that the "ACARS automatic reports" were just the final part of the problem, when there was allready no hope left for those souls.
This has been what my experience has been saying to me all along (structural breakup due over-stressing during entry into a CB, ACARS messages recording the effects of subsquent failures, unrelated to cause), but there was simply not enough evidence to state it and so I remain uncommitted to any conclusions still. The Perpignan intact fin (we don't know what the same structure looks like however), keeps the question suspended somewhat.

[wes_wall]

This has been what my experience has been saying to me all along

No doubt there are many who share the same thoughts, but there is nothing which has been discussed that offers any credible evidence to any onset of trouble. What ever happen occured prior to the first ACAR.

[gem1]

I am suspicious of the early fault message of the TCAS system antenna.

Where in the A330 TCAS antenna located?

My guess is TCAS is partially driven by GPS, and the antenna may have been located on the rudder, humm. If it was located there, the big event was over in the first seconds?

[Lost in Saigon]

I am suspicious of the early fault message of the TCAS system antenna.

Where in the A330 TCAS antenna located?

My guess is TCAS is partially driven by GPS, and the antenna may have been located on the rudder, humm. If it was located there, the big event was over in the first seconds?


Haven't we already discussed this? Deja Vu all over again?

http://i2.photobucket.com/albums/y17/msowsun/Airline/AF447_TCAS.jpg

[augustusjeremy]

Consider the A320 crash near Perpignan. Apparently they failed to recover from slow flight around 3000-3800msl and descended into the sea.



By the way the interim accident report for this flight seems to be very worth reading.

http://www.bea.aero/docspa/2008/d-la081127ea/pdf/d-la081127ea.pdf

[SaturnV]

mseyfang, the Brazilian map showing where bodies were recovered was generally along a SSW-NNE axis. The current at 4N 30W is from east to west. The prevailing surface winds in that area would also be from east to west.

http://i136.photobucket.com/albums/q199/tahitiplage/SNAG-0264.jpg

Chart from Wiki.

[Rananim]

This isnt the time for internal squabbling.I dont know about others but I find posts from the self-appointed experts just as annoying as repeated enquiries about the ACARS LAV message.And they want to restrict contributions to this type of thread to pilots only..Last 2 constructive posts came from A330 tech and Fly by wife(#765) so go figure.Its all guesswork,all speculation,we know that.What is the alternative?Enforced silence.Is that better?

Naturally,the picture of an almost pristine and complete VS bobbing in the Atlantic and the report that bodies have been found 85kms apart seems like a smoking gun but I'll go along with ELAC(for now) and accept that they may not have encountered weather,lost airspeed and perhaps attitude reference and got their VS torn clean off in the ensuing upset.I see 411A was shot down in flames but what he said is correct.Use rudder(significant amount) for anything other than x-wind/asymmetric flying in a commercial transport and you do so at your own peril.Not suggesting AF crew did this(just in case ELAC
is still in"police" mode).

The Air Caraibe incident needs to be examined(the value of a precedent in any investigation is immeasurable) and focus maintained on the ACARS messages.

[Lookleft]

The AA acident was not the only occasion that a rudder separation was a major factor in an accident. There was another incident when a significant section of either rudder or V/S come off on an A310 somewhere in the Caribbean. What was of interest in the photo of the AF V/S section is that it was not attached to anything else. This leads naturally to speculation (which is what all these posts are) that the V/S may have separated from the rest of the aircraft. Its obvious that there is much more that needs to be looked at but I could well imagine that the investigators will be instigating another line of investigation.

[PJ2]

wes wall;
No doubt there are many who share the same thoughts, but there is nothing which has been discussed that offers any credible evidence to any onset of trouble. What ever happen occured prior to the first ACAR.
Yeah, I don't think we're alone by any stretch - probably most crews here are quietly expressing the same thing when they discuss it, but there's just nothing to peg the "sense of it" on yet.

ttcse;
I also believe it keeps the af447 tail discussion inconclusive.
Yep. It's as inconclusive right now as it was a week ago last Monday. All we have are some disparate facts which cannot be placed in the accident sequence, and a few knowns such as the condition of remains, and of the vertical stab.

I might observe that the "CREW REST" wreckage may likely be from the F/A crew rest module, not the cockpit crew rest area. I say this because the cockpit crew area is not labeled, it generally being near the cockpit. But the F/A module is, in some cases, removable and as such, labeling makes a bit more sense, (when stored...not when 'in use'). The location of this module varies with airline - some are mid-wing, others near the tail section; to the best of my knowledge, all such modules are below the main cabin floor.

[Graybeard]

Thanks for the diagram of antenna locations, Saigon Lost. It gives evidence that the vertical fin was intact throughout the period of the ACARS reports, else there would have been HF Fail reports, too. The VOR antennas are not monitored, but the HF antenna couplers, in the leading edge of the vertical fin, are active LRU, Line Replaceable Units, that are powered, and provide fault reporting to the transceivers, which would, in turn, report to the ACMS, and from there to ACARS.

GB

[Finalapproach9L]

Respectfully, I submit the following:

I was wondering about specific change points , and inflight shift change. And if there was a crew change once it was at cruise? I recall awhile back mid 1990s, ARSR report referencing some LH transition issues.

[Lost in Saigon]

Respectfully, I submit the following:

I was wondering about specific change points , and inflight shift change. And if there was a crew change once it was at cruise? I recall awhile back mid 1990s, ARSR report referencing some LH transition issues.

How can there be any "issues" with crews taking breaks?

At my airline we have 3 pilots on flights over 9 hours. Typically on a 10 hour flight all 3 pilots are in the flight deck for 30 mins after T/O and 30 mins before landing.

The remaining 9 hours would be split into 3 hour breaks for each pilot. Junior guy usually takes the first break and the flying pilot takes his choice.

Longer flights would sometimes get a long and short break for each pilot.

[pool]

How can there be any "issues" with crews taking breaks?

The issues might be somewhere else. No problem with breaks, it only depends WHERE the crew can rest and HOW.

First, if you need to rest right after beginning duty, you'r rather sit, eat, read or watch a movie to relax, because you can't sleep just having barely gotten up. Some airlines just provide a sleeping tube, that's it! You can't eat or sit up for hours!! Rest is reduced to torture and basically not giving what was intended, you'll get red-eyed pilots. Safety compromised.


Second, if the crew rest facility is way back in the aircraft (especially if it is a mobile one), then access confines you to travel through the whole cabin, during service, or worse, during a uncontrolled flight phase and panicking passengers. Why would this be an issue? Simply because in a 3 man cockpit, the captain will also rest, typically in the middle of the flight (!) and would want a rapid access to his seat in case of trouble. Furthermore it has been proven over and over again, that in trouble all hands on deck helped save the flight. 3 men are better than 2 with increased and emergency workload. Placing crew rest away from the cockpit might save money, but you compromise safety again. This is not only a Airbus issue, mind you.

Two questions arise here:
- When was the skipper resting? Was he in the cockpit?
- Where was the crew rest bunker placed? Could the 3rd pilot access the cockpit in due time to help?

[WNcommuter]

Thanks for the diagram of antenna locations, Saigon Lost. It gives evidence that the vertical fin was intact throughout the period of the ACARS reports, else there would have been HF Fail reports, too. The VOR antennas are not monitored, but the HF antenna couplers, in the leading edge of the vertical fin, are active LRU, Line Replaceable Units, that are powered, and provide fault reporting to the transceivers, which would, in turn, report to the ACMS, and from there to ACARS.

Awesome post. A perfect example of why this board rocks! You just crossed the early breakup hypothesis off the list.

[Graybeard]

Re-thinking the TCAS Fail report, and inputs that could have caused it:

Airspeed: airspeed has no input to the TCAS, so possible clogged pitot is unrelated.

Altitude input fail: Altitude data goes to the transponder, not the TCAS processor. Transponder would report Altitude Fail, but that is redundant with the ADIRU air data fail message, so may be suppressed. Transponder would revert to Mode A, making the TCAS inoperative, which would trigger a TCAS message. It's hard to tell from the ACARS reports if the Altitude function of the ADIRU was inoperative as well as airspeed.

Attitude Fail: Pitch & Roll are fed to TCAS, so IRU Fail would trigger the message.

Heading Fail: used only for smoothing target movements, so not worthy of a TCAS report.

Radio Altimeter: unlikely that both could fail at this time, although they can lock onto really heavy rain, but not at FL 350.

Antennas: A TCAS antenna fail would trigger TCAS Fail. Hate to say it, but one cause could be lightning.

GB

[SaturnV]

Air India 182 was restricted to 35,200 feet and 290 knots as it was ferrying an engine. The bomb detonated while the plane was at 31,000 feet and 296 knots. The plot of the wreckage on the sea floor revealed that it was mostly scattered along a NW-SE axis over a distance of 6.5 NM, or generally between 12.49W and 12.41W. The westernmost definitively identified portion of the wreckage was found at nearly 12.50W. Lighter and smaller pieces constituted most of the wreckage on the easternmost portion of the axis.

Plot can be seen here on the last page of the pdf.

http://www.publicsafety.gc.ca/prg/ns/airs/_fl/CASBai-en.pdf

All the bodies were recovered within five days, which may have been more a function of the plane being tracked by radar, and relative proximity to the Irish coast. The report does not indicate there was significant dispersal of floating wreckage by current or wind. Between 3 and 5 percent of the plane was recovered as floating wreckage.

[lhr_syd]

I admire the way you deduce and reason, Graybeard :ok:. Makes this thread worth following. Thank you.:D

[GE90115BL2]

POOL..........this is NOT an Airbus or Boeing issue ( crew rest location )

It's the AIRLINE that specify where the rest is located depending on how cheap they are.

The 777 has an overhead crew rest for the cockpit crew above the first class cabin available, BUT some Airlines choose to go with a cheaper option instead. ( down the back cargo hold )

So don't blame Airbus or Boeing.:ok:

[condorbaaz]

In my understanding

tropical storms have a lot of energy esp at lower levels.

Like Tagor sys, Lateral separation is often the best.

While at low altitudes, the speed margin is more, so is the severity of turbulence and icicng esp at SAT above -40 deg C

Further in Europe and in any monsoon type of weather, at lower levels one would definitely be in icicng conditions for a longer period of time .

I suppose it would be a calculated risk at the time to go around a storm (if you can vertically?) vs through it.

Hope this helps...

[zekettledrum]

Mods please...Some of these first time posters obviously have no knowledge of aviation! I suspect some of them are media.That is why the forums have a report this post function. Replying to (and quoting!) the offending post is not likely to be spotted by the mods as quickly as reporting a post will be. You click on this - http://static.pprune.org/images/buttons/report.gif - just over in the left hand area, beneath the poster details, to report a post.

[pool]

GE90115BL2 wrote:

It's the AIRLINE that specify where the rest is located depending on how cheap they are.

The 777 has an overhead crew rest for the cockpit crew above the first class cabin available, BUT some Airlines choose to go with a cheaper option instead. ( down the back cargo hold )
So don't blame Airbus or Boeing.http://static.pprune.org/images/smilies/thumbs.gif

It's precisely for guys that have a problem with AB vs. B that I wrote:

Placing crew rest away from the cockpit might save money, but you compromise safety again. This is not only a Airbus issue, mind you.

:ugh:

[ELAC]

Naturally,the picture of an almost pristine and complete VS bobbing in the Atlantic and the report that bodies have been found 85kms apart seems like a smoking gun but I'll go along with ELAC(for now) and accept that they may not have encountered weather,lost airspeed and perhaps attitude reference and got their VS torn clean off in the ensuing upset.

@Rananim

Now hold on a minute there Sunshine. I stated absolutely nothing of the sort. The only thing I have stated is that there is no evidence available from which the actual track of the flight relative to the weather can be determined. Did they deviate or not, I don't know and neither do you. Did the accident occur from inadvertent penetration of a CB causing an upset? Or, was it the result of circumstances similar to those experienced by the Air Cairibe flights while deviating around convective weather but while still in cloud compounded by an ensuing incorrect pilot response? Or, is it possible that the accident resulted from an extreme turbulence upset while deviating clear of the storms?

Three different possibilities (at a minimum) with different implications regarding potential failures of the aircraft or the crew. None can be proven without the requisite evidence, so what's the point of pre-judging on the basis of the limited bits of information we do know?

ELAC

[Captain-Crunch]

Captain Flame posted:


Let's put this one to rest once and for all !

The message F/CTL RUD TRV LIM Fault is justified by the loss of the ADR data.

As said previously in this thread, the rudder travel is then limited to 10 degrees and full deflection is only recovered at slats extension.

An Air Caraibe A330 incident report is circulating (in french) which describes a (survived) event sounding very similar to the AF447 event.

In the air Caraibe event (which I will try to find in english)....icing over of the Ptot probes and TAT probe at FL 350, in transoceanic equatorial WX, with severe turbulence, occured.
The following ECAM messages, flags and system reversions are consistent with the ones reported ont the AF447 ACARS report.

As decribed earlier in this thread, the TAT increase from -14 to -5 degrees typical of an iced up probe measuring the ice temperature instead of the Ram Air.
At some point in this event the CAS, MACH and ALT go respectively from 274Kts, M0.80 and FL350 to 85kts , M0.26 and FL347.

At the same time the cascade of ECAM warnings and cautions include NAV ADR Disagree, F/CTL ALT LAW, F/CTL RUD TRV LIM, ENG EPR mode faults (different engines there), Speed Flags on PFDs, loss of FDs, A/THR, etc....Including at some point STALL STALL audio warning (no protection in ALT LAW)

Summarily, the PF flew "pitch and power" with PNF on QRH unreliable speed indication, disregarding the STALL warning and using backup info of GPS Ground speed and Altitude (ND and FMGC).

Air Caraibe has modified all the 330 probes earlier this year.

Again, the Air caraibe report is VERY similar to what is now known of the AF447 troubles. (Weather, turbulence, airspeed data problems)


Guys I'm on the other side of the world, so while most of you are posting and moving on to other subjects, I'm counting sheep and then still responding to the "resolved" posts the day before! Forgive me if I'm five pages behind. :8

I hadn't read this A330 report earlier even though I downloaded it. Even though it is in French, It's clear most of the "events" logged about the accident/incident are almost identical. As the good "Captain Flame" stresses the engine EPR differences are moot, they are just airline customer engine selection options: For example on the previous gen aircraft the A310, you could order with Pratts w/EPR or GE's w/out EPR. In the latter case, since all you have is N1 for thrust settings you wouldn't get EPR (engine pressure ratio) errors logged (since you don't have those gages), you wouldn't see those EPR faults or warnings into the mtc computers. The aircraft system then reports these conditions to ACARs, and ACARs would then bundle this information into a data packets and beam it to the satellite or HF if, that service was paid for.

To oversimplify for non aviation types: ACARS is a telephone. If the Cable Guy (Installer) has problems with your TV/black box, he's going to ask you to use your telephone (ACARS) to report the faults to somebody back at his company (AOC/Maintenance Control) who is smarter than he is. Previous posters asked where the location coordinates for the last 0214z acars report came from since it didn't show up in the acars report. This is a good question. It appears the images on the first few pages of this thread from Channel2 France, are of a finished "environmental" report constructed for AF maintenance. We are not seeing the actual data packets (which would have sat broadcast coordinates,) which are broadcast line-of-sight to the satellite in a different computer language.

Here are excerpts from Wiki on ACARS:

SATCOM and HF subnetworks
SATCOM provides worldwide coverage, with the exception of operation at the high latitudes (such as needed for flights over the poles). HF datalink is a relatively new network whose installation began in 1995 and was completed in 2001. HF datalink is responsible for new polar routes. Aircraft with HF datalink can fly polar routes and maintain communication with ground based systems (ATC centers and airline operation centers). ARINC is the only service provider for HF datalink.
[edit]Datalink message types
ACARS messages may be of three types:

Air Traffic Control (ATC)
Aeronautical Operational Control (AOC)
Airline Administrative Control (AAC)

ATC messages are used to communicate between the aircraft and Air traffic control. These messages are defined in ARINC Standard 623. ATC messages are used by aircraft crew to request clearances, and by ground controllers to provide those clearances.
AOC and AAC messages are used to communicate between the aircraft and its base. These messages are either standardized according ARINC Standard 633 or defined by the users, but must then meet at least the guidelines of ARINC Standard 618. Various types of messages are possible, and these include fuel consumption, engine performance data, aircraft position, as well as free text data.....

(Each airline must tell its service provider(s) what messages and message labels their ACARS systems will send, and for each message, where they want the service provider to route the message. The service provider then updates their routing tables from this information.) Each type of message sent by the CMU [Communications Management Unit - CC] has a specific message label, which is contained in the header information of the message. Using the label contained in the message, the DSP looks up the message and forwards to the airline’s computer system. The message is then processed by the airline’s computer system.
This processing performed by an airline may include reformatting the message, populating databases for later analysis, as well as forwarding the message to other departments, such as flight operations, maintenance, engineering, finance or other organizations within an airline. In the example of a delay message, the message may be routed via the airline’s network to both their operations department as well as to a facility at the aircraft’s destination notifying them of a potential late arrival.

Those who claim that the ACARs data doesn't mean anything, are incorrect.
These messages are the best information we have thus far and they appear nearly identical to other A330 known mishaps. If history is any guide, since billions are on the line in Aircraft Ops and Sales, it may be years before the findings of this investigation are made public.

All my posts are just my opinion only.


CC

[vapilot2004]

Not saying ACARS messages are related to loss of VS.
............................................Doesn't help thread to try to put words in other poster's mouths.

Actually your post appeared to have alluded to this indirectly. I responded, but relented and was deleted.

No harm done I hope. It was getting tiring hearing about vertical stabilizers and the loss of AF447. The two are unrelated at this point as a causal factor according to the information, scant as it is, provided so far.

Even the Seattle Post had an 'engineer' claim the Rudder TRVL Limit message was not a reported fault of the limiter, most likely due to the loss of ADIRU data, but an actual rudder over-excursion.

I had previously posted a correct interpretation by a retired but qualified A330 engineer to the contrary and explained it in this post (http://www.pprune.org/rumours-news/376433-af447-47.html#post4985889) of mine earlier.

Sorry if I was a bit too harsh 727gm.