AF447

[FatherStorm]

As a non-pilot, but a denizen of the web since '89 I would argue that though discussion of posting rights, or posting rankings *may* have merit. Locking the forum to pilots only is not in the best interests of anyone. The purpose of the http protocol was and is the providing of information to all without qualification of their *right* to access it. I still long for the day long past when I could "talk". (Old unix cvommand) to anyone with a email address and logge on and receive an expert opinion. Yes the uneducated tend to offer bad info, but good info comes with sources and supporting arguments. Allow me a source of knowledge, my government and my media do enough to protect my fragile mind already .

[Dysag]

The first Airbus cockpit crew rest (A340-300) was two bunks accessed directly from the flight deck. It wasn't popular because there was no sitting area and it tended to be noisy.

On current A340s it normally occupies part of the bulk hold space, so a long way from the flight deck, but equipped with proper seats. I'm not sure if this is available on the A330-200. Maybe an AFR person can tell us.

The debris from AF447 with "crew rest" on it almost certainly indicates it's an LDMCR - lower deck mobile crew rest. This container-like module, primarily intended by Airbus to be for cabin crew rest, occupies the forwardmost position in the rear hold. Again, maybe someone from AFR can tell us whether this was being used as cockpit crew rest.

[Graybeard]

Agreed on the inputs to TCAS, Plastic Bug. I believe the TCAS Fail came before the IR Fail, though. Not so?

I'm from the planes of separate DADC and IRU, where the failure of one, or a component of one would not condemn the output of the remainder. Is that still not true? Can you not get Airspeed Fail out of the ADIRU without Altitude Fail? If not, it's a giant step backward.

I suppose it's possible for the airspeed word to go Fail Warn, with Altitude reporting Normal (condition), and getting lumped together in the ACARS message as ADR Fail. After all, MTC just needs to know which box to change..

GB

[jmig29]

TCAS is just a visualization and warning processor based system to the pilots. If you loose it, you will still have Mode S ATC XPDRs, but the opposite is not true, if you loose ATCs, you won't have TCAS.

[paull]

Unless I missed the times at which these two bodies were found then we can conclude nothing. If one was found at A and the other days later at B then all we need is that they were far enough apart for the second one not to be seen when the first was recovered and normal currents would then move it somewhere else in the intervening period. We do not need diverging currents at all.

Of course, the Brazilian Navy have the data, they can superimpose the drift and decide if the data is inconsistent with intact entry to the sea. We can make no such inferences at present.

[Captain-Crunch]

Greybeard said:
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

:D

Great Work Greybeard! The HF was most likely operational until 0214z (we say this, because of the absence of a LRU ACARS message of it being faulted). Therefore, the vertical stablizer was intact and had not left the airplane before 0214z.

This Means that the ACARS messages probably preceded the fatal loss of control event.

(recall, that my high dive estimate is 60 seconds from jet upset FL350 to 10-14K recoverable air. Please challenge this if you can prove a different elapsed time from FL350.)

Again, outstanding work guys.

This board is way more than speculation with guys like Greybeard posting.

CC

[Interflug]

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.we say this, because of the absence of a LRU ACARS message of it being faultedI just wish we knew:

-the complete unfiltered information as transmitted by AF447 (what was transmitted)
-a list of all possible failure and warning items specified by AF for immediate transmission. (what qualifies for transmission)

[CaptKirk]

.... This Means that the ACARS messages probably preceded the fatal loss of control event. Again, outstanding work guys. This board is way more than speculation with guys like Greybeard posting. CC So you\'re saying the plane encountered trouble before it went out of control? And VS detach wasn\'t the cause?

[jmig29]

The A330 AMM looks very similar to the A320’s.

So, for all experts here goes the “chapter decoding” of the ACARS messaging.

Please note that all lines stating “maintenance status” at the end of the line are Class II faults, therefore not critical.

And yes, the Aupilot will disengage if it feels it’s not able to control the A/C in severe weather.

2723………. Rudder travel limiting
2283………. FMGEC
2283………. FMGEC
3443………. TCAS
2230………. A/THR
2283………. FMGEC
2283………. FMGEC
2791………. EFCS
2262………. FMGEC – FLIGHT ENVELOP
2210………. AP/FD
3831………. (WASTE) LAVATORY CONFIG
3831………. WASTE VACUUM SYSTEM GENERATOR

2131………. CPC (CABIN PRESSURE)
2283………. FMGEC
3410………. ADIRS MAINT STATUS
2790………. FCSC 1 FAULT
2790………. FCPC 1 FAULT
3412………. ADIRU 2 INOP
3412………. ISIS (ELECTRONIC STBY HORIZON)
3410………. AIR DATA DYSAGREE
3412………. ADIRS
3412………. ADIRS
2793………. FCPC 1 FAULT
3411………. PITOT 9Dax PROBE INOP
2790………. EFCS MAINT STATUS
2790………. EFCS MAINT STATUS

[CaptKirk]

Thanks JMIG29 But is it staggered or is it a complete disengage, and what are the parameter for partial? I ask because maybe the pilots found themselves with incomplete control after a partial AP disengage. [brk] And maybe they weren\'t aware of it- wouldn\'t be the first time.

[jmig29]

Complete pitch and roll auto comand is lost. Rudder comand is always present from FCPC's (I think, remember I'm not familiar with this A/C) which acts pretty much the same way of FAC's and ELAC's, on A320.

Unless it moves out of normal law, down to direct law.

[PJ2]

The information provided on Alternate Laws 1 & 2 from an A330 AOM ATA Chapter 27. While the ACARS message 2791 indicates "F/CTL ALTERNATE LAW, we do not know what caused the flight control reversion The potential causes are listed in the previous post:


ALTERNATE LAW 1

PITCH CONTROL

Ground mode
Identical to normal law ground mode.

Flight mode
Flight law is a load factor demand law, similar to normal law, with limited pitch rate feedback and gains, depending on speed and configuration.

Note : When the yaw dampers actuators are not available (hydraulic G + Y failure for example), the yaw damping function is made through the ailerons and the BYDU.

Flare mode
Flare law is identical to normal flare law.

LATERAL CONTROL
Lateral control is similar to normal law, except that alterations of positive spiral static stability will not occur due to the loss of high AOA and high speed protection.

PROTECTIONS
Low speed stability
At low speed, a nose down demand is introduced in reference to IAS, instead of angle of attack, and alternate law changes to direct law.
It is available, whatever the slats/flaps configuration, and it is active from about 5 knots up to about 10 knots above the stall warning speed, depending on the aircraft's weight and slats/flaps configuration.

A gentle progressive nose down signal is introduced, which tends to keep the speed from falling below these values. The pilot can override this demand.
Bank angle compensation is provided.

In addition, audio stall warning (crickets + “STALL” synthetic voice message) is activated at an appropriate margin from the stall condition.
The PFD speed scale is modified to show a black/red barber pole below the stall warning.

Vα prot and Vα max are replaced by Vsw (stall warning speed).
The α floor protection is inoperative.

ALTERNATE LAW 2

PITCH CONTROL
Identical to ALT 1 law.

LATERAL CONTROL
Roll direct law
Provides a direct stick-to-surface position relationship. The gains are automatically set according to the slats/flaps configuration.

The maximum roll rate is approximately 20 to 25° / second, depending on the speed and
configuration.
Spoilers 2, 3 and 6 are inhibited, except in case of some additional failures affecting the lateral control.

Yaw alternate law
The dutch roll damping function is available, and damper authority is limited to ± 4° rudder (CONF 0) and ± 15° (other configuration).
Turn coordination is also provided, except in CONF 0.

PROTECTIONS
Identical to protections in ALT 1, except that :
1. There is no bank angle protection in ALT 2 law.
2. In case of failure of 2 ADRs, there is no low speed stability.
3. In case of failure of 3 ADRs, there is no high speed stability.

[Boomerang_Butt]

Just a couple of questions (no expertise aside from being CC flying on the Airbus family)

I've tried reading through but this thread has gone from page 33 to 43 in the time I've been reading.... so, apologies if this has already been answered.

I know there are a couple of posters here involved in SAR operations... would use of satellite imaging be at all useful in helping to locate debris/people and so on... I mean some posters are saying there is a lack of a 'dense debris field'.. but how can we really know that in such a large area? (currents/winds prediction aside) Could there be other areas of debris/people which will not be found for days/weeks/months/ever? So would there be any coverage to a degree which would give any help in finding (large) areas of debris, or is it kept to the old grid/search pattern method by air/sea vessels? Would anyone in possession of such pictures likely not be willing to admit it (for political reasons)?

and 2.

Why is everyone getting so hung up on radios/comms/maydays etc, when we may not ever know if the crew did, or did not, communicate... simply put, (and I'll ask as a question to refrain from 'speculating') could they have been trying multiple times to have contact and it was never heard? I gathered from earlier postings this could be the case given the remote area & being out of the radar coverage/difficulties with HF etc in weather... not to mention having their hands full.

Again, I leave it to those with more experience than I, was just wondering about the satellilite thing today while looking out the window thinking what a wide area the ocean is from that high... :(

[BOAC]

May I just interject to let you know that the JB thread (as ever, well-moderatedin a JB sort of way:)) has a lot of good stuff on it and may be worth keeping an eye on. You'll have to ignore the usual JB crap, the Comet crash stuff and the immoderate rantings of Captain Stable against Arcniz, but a few reasoned posters appear to have sought refuge there from this jungle. A couple of unseen pics there too.

[Professorrah]

Interesting, where did you find that info, I was looking at the site but found nothing?

[BOAC]

My apologies to the 'newbies'. Here is the link (http://www.pprune.org/jet-blast/375943-air-france-jet-missing-16.html)

2 more:

Can we stop asking about whether the Captain was in bed at the time/issues of crew rest etc? I cannot envisage ANY captain faced with crossing the active ITCZ and with 6-7 hours of 'peaceful' cruise thereafter, retiring to bed and leaving the rest of the pilots to 'get on with it'.:ugh:

Are there any AF pilots here who can elaborate on the (supposed) crew report of 'turbulence fortes'? Is that an established AF description?

[Kerosene Kraut]

Apologizing if I missed it up here -
There seems to be a new EASA recommendation concerning unreliable airspeed indications. Airlines are requested to keep crews current and checked on the procedures.

Source (german)
EASA gibt nach Absturz im Atlantik Sicherheitsempfehlung an Airlines heraus - FLUG REVUE (http://www.flugrevue.de/de/zivilluftfahrt/airlines-flugbetrieb/easa-gibt-nach-absturz-im-atlantik-sicherheitsempfehlung-an-airlines-heraus.11400.htm)

[ManaAdaSystem]

I don't buy into the; "They lost the VS and crashed" theory, but would a missing HF antenna coupler/LRU trigger a HF fail message? Is this a monitored device, or does it transmit an error message itself?

[Professorrah]

Interesting link Kerosene but hopefully crews are kept current and checked on the procedures anyway:)

[Kerosene Kraut]

I agree. It looks a bit like EASA blaming airline flight ops/training instead ot it's own certification standards. I mean if tropical weather conditions go beyound the ones used for certification maybe the standards should be modified?

[PapaEcho]

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


Sorry GB,
but with 3 IR Fault, ADIRU-2 Fault and so on ADIRU-1/-3 Disagree...any doubt why TCAS had fault? NO IR no Position NO ADR no Attitude, the TCAS become a $ 13.000 mirror with black bright glass! :}

Cheers,
PapaEcho

[etsd0001]

but would a missing HF antenna coupler/LRU trigger a HF fail message? Is this a monitored device, or does it transmit an error message itself?

1. You can't fly with a componant missing

2. A faulty coupler sends discretes to the HF T/cvr which in turn reports to the CMC. An ACARS msg will then be sent.

The only msg;s ECAM will give you are

HF 1(2) Data Fault

HF 1(2) Emitting

[parabellum]

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

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

[poison]

Dear Ladies and Gentlemen,

The following information that is posted in this reply is something that may interest you all. The scenario was conducted several times and the results at the end of each scenario produced consistent findings.

In an A330 simulator at FL 350 with a gross weight of 210 tonnes in ISA+10, with icing selected, the aircraft approaches a thunderstorm with a high intensity of turbulence. Due to the extreme turbulence, the autopilot disengages. Shortly thereafter a malfunction is selected to block both captain and first officer's pitot tubes to replicate extreme ice formation.

The airplane reverts to alternate law with protection lost. There is a speed flag on both the captain and fo's PFD. The severe turbulence activates repeated stall warnings. Manual thrust is being used at this time. The speed on the standby altimeter is reading 240kts or thereabouts with MACH .72. From the GPS the ground speed is 350 kts or thereabouts. It is very difficult to read the instruments and ECAM warnings.

Updrafts take the aircraft up to FL 370 and produces a negative G of .2. The aircraft then enters severe downdrafts and the rate of descent averages more than 19,000 fpm. The instinctive reaction is to pull on the stick to arrest the rate of descent. The aircraft shakes and buffets violently. The G force on the SD reads +5 but the instructor's panel shows +8. The aircraft breaks up in flight around 20,000 ft.

After several attempts at this with all results being equal one could not see AF447 sending out any distress signals if this is what happened to them. Applying an unreliable airspeed memory item would have proven to be very difficult because of the violent shaking and opening a QRH for an ADR check procedure even less likely.

[Graybeard]

Thanks for the acknowledgements regarding the HF. It relieves me after having some posts deleted from the prior thread, and to me they were hardly less valid.

Why have ACMS? Why have ACMS reporting via ACARS? It's to reduce delays on the turnaround. So yes, dual HF, being required for overwater flight, will be reporting to the ACMS and linking via ACARS. It's common sense that a Failed HF won't be transmitting its own failure, btw.

Here's what I replied to a PM from a doubter: Cut the wires between the HF transceivers in the fuselage and the HF antenna couplers in the fin, and the HF will send a Fail message to ACMS. The coupler is actively tuned to resonance with the antenna each time the frequency is changed, and reports Tune in Progress and Tuned to the transceiver before transmit is allowed.

If you've used airborne HF, you know the Tune Tone. It's quite short, however, with the new electronically tuned couplers of the last ten years, but still occurs.

GB

[Nicolaus Silver]

With constant cross examination of many facets that eventually may not be applicable in this incident, we are still exposing safety considerations which could be included in future equipment, design, operational practices and commercial integrity. If foul play was the cause then that will need to be managed in the industry and politically.

As a passenger I am reassured and intrigued by the debate on this site and my kid entering aerodynamic engineering is learning heaps.

Humans have been flying for barely a 100 years and will continue to learn by mistakes. As a passenger I accept that risk BUT to short cut safety to save 1% or reduce a fare by $50 is not what shareholders or consumers need.

Thanks to everybody for your input.

[Graybeard]

Somebody questioned if HF Fail reports had been deleted from the ACARS messages. That would need a conspiracy.

GB

[ManaAdaSystem]

If the VS was missing, the coupler would be missing, hence my question.

Thanks Greybeard, for your answer.

[Mad (Flt) Scientist]

Somebody questioned if HF Fail reports had been deleted from the ACARS messages. That would need a conspiracy.

GB

I believe BEA have stated that there were 24 messages received from the a/c, but not what they were.

The "unofficial" ACARS list has 24 entries for AF447.

Unless it's a total red herring list planted to divert everyone (just how paranoid are you prepared to be?!), it seems likely we have the messages, and all the messages, that were sent.

[Safety Concerns]

We do all understand the differences between ACMS, CFDS, CMS and ACARS don't we.

Would hate to think there are some amateurs out there pretending to be professional

[nsxtasy]

Poison:
Dear Ladies and Gentlemen,

The following information that is posted in this reply is something that may interest you all. The scenario was conducted several times and the results at the end of each scenario produced consistent findings.

In an A330 simulator at FL 350 with a gross weight of 210 tonnes in ISA+10, with icing selected, the aircraft approaches a thunderstorm with a high intensity of turbulence. Due to the extreme turbulence, the autopilot disengages. Shortly thereafter a malfunction is selected to block both captain and first officer's pitot tubes to replicate extreme ice formation.

The airplane reverts to alternate law with protection lost. There is a speed flag on both the captain and fo's PFD. The severe turbulence activates repeated stall warnings. Manual thrust is being used at this time. The speed on the standby altimeter is reading 240kts or thereabouts with MACH .72. From the GPS the ground speed is 350 kts or thereabouts. It is very difficult to read the instruments and ECAM warnings.

Updrafts take the aircraft up to FL 370 and produces a negative G of .2. The aircraft then enters severe downdrafts and the rate of descent averages more than 19,000 fpm. The instinctive reaction is to pull on the stick to arrest the rate of descent. The aircraft shakes and buffets violently. The G force on the SD reads +5 but the instructor's panel shows +8. The aircraft breaks up in flight around 20,000 ft.

After several attempts at this with all results being equal one could not see AF447 sending out any distress signals if this is what happened to them. Applying an unreliable airspeed memory item would have proven to be very difficult because of the violent shaking and opening a QRH for an ADR check procedure even less likely.


This could then explain why debris being located at present is both away from the flight plan, hard to locate, and now surfacing. The VS for example being in relatively good shape could have fluttered down like others have suggested. Considerable numbers if +5 or +8 g is reached.:eek:

[bobrun]

The G force on the SD reads +5 but the instructor's panel shows +8.
In alternate law 2 (ADR DISAGREE), the load factor protection is still available, so I don't see how this scenario is likely. Pulling full aft stick wouldn't result in +8G.

The A330 Air Caraibes incident report is interesting in that it clearly points out that the Unreliable Airspeed procedure may need some more "thoughts".

The procedure instructs to "Respect the Stall warning, and disregard the Risk of Undue Stall warning status message, if displayed on ECAM". However, in the A330 Air Caraibes incident where the pitot and TAT probes were iced up, the crew did receive two Stall warning that were actually false. Had they "respected" the stall warning and applied TOGA while lowering the pitch, you can imagine what might have happened. There's also the issue of the confusion that comes from the ECAM saying one thing, and the paper procedure saying the opposite.

The full report is available online, for those who can read French. The description of the warnings they received are very similar to those apparently received by the AF crew, so a parallel can easily be drawn.

[Graybeard]

SC: "We do all understand the differences between ACMS, CFDS, CMS and ACARS don't we."

Yes, I used the abbrev. ACMS, a Boeing term, when it should have been CFDS. At least it was CFDS at A/B back in the beginning of condition monitoring. The two systems differed in construction, but the resulting output to the ACARS is effectively the same. Has A/B replaced CFDS with something else when I wasn't looking? ACMS and CFDS required different outputs from the LRUs, and so unique part numbers.

GB

[Captain-Crunch]

PJ2,

Thanks for the great scans. :8

Almost certainly. As we examine the ACARS messages for the traces of failure and/or system degradation, we must accept also, that either parts of the same systems remained operational without serious fault or the ACARS did not report any such faults in time.


Yes, I should have said operational HF antenna, since that is what Mtc monitors in the tail. In my readings I came accross a comment that when the ACARS transmission fails (which Greenspinner says is attempted in microseconds after "Mother Computer" tells it what's wrong with the ship), then:

"The ACARS also contains protocols to support retry of failed messages or retransmission of messages when changing service providers."

Interfug asked if it's a complete list, So: How often does it retry? We know it got off what? 27 total faults and warns (including 3 mtc status wrns) for four minutes straight, so the acars system had normal DC and was functioning. I don't see how there could be any missing messages between 0210 and 0214z since ACARS breaks the info up into blocks (where's AVspook?, he probably knows the answer to this) This is the world of data bits and verification and secondary resends: only a real "TRON" can verify that when it's got a lock it's streaming fast. Wiki only says:

It should be noted that the majority of ACARS messages are typically only 100 to 200 characters in length. Such messages are made up of a one-block transmission from (or to) the aircraft. One ACARS block is constrained to be no more that 220 characters within the body of the message. For downlink messages which are longer than 220 characters, the ACARS unit will split the message into multiple blocks, transmitting each block to the RGS (there is a constraint that no message may be made up of more than 16 blocks). For these multi-block messages, the RGS collects each block until the complete message is received before processing and routing the message. The ACARS also contains protocols to support retry of failed messages or retransmission of messages when changing service providers.

System redundancies may or may not mitigate controllability issues.

What is the likelihood for example, that both TAT's would ice over at the same time? I realize that the theory on emergent warm air could make this question immaterial but we dont' know that and must ask the technical question.

Very high, if you know how to "sinc the props" and trim it straight, :}, unless the fuselage is in a sideslip. It's an airmass issue. You've just hit humid icy warm (less than -40SAT) air. When it happened to me on the A310, all hell broke loose at once. Red Zippers, Stall Warnings, A/P disconnect, A/T to Thrust Latch. And no believable a/s anywhere. This was in the day. Ice was visable on both wipers. If the cause is warm air bubbles from King Neptune, then why aren't B747 guys loosing control? I'm suspicious it's more than just luke-warm/poorly designed pitot probes and static ports. It's gotta have something to do with the Airbus logic (born in the A300) when "Mother" the computer, encounters an event that engineers taught her was impossible.

Side note: we had alternate static port valves near your knee that could be opened on the A310. We didn't since I was hanging on for dear life and the F/O turned into Frosty. 3degrees and 90% worked and several minutes later in the clear probes melted it off and we wrote up a Aviation report and nobody believed us.

Has it been established beyond doubt that all three pitot heads failed within the four minute period and may be considered causal vice an outcome, in any theory? Even then, we do not know the failure mode...a complete loss of data or residual but degraded data?

Greenspinner seems to think so consulting his TSM. To me this means no loss of power to the ADIRU's but loss of just the Air Data half that makes "Mother" think it's failed. But Greenspinner said it looked like to him complete loss of the unit's power..... gulmp. (if I am quoting him right.)

Do the PFD faults indicate a serious failure or do the four (I think), ACARS messages indicate only one or two of the 24 possible fault messages concerning the PFD's?


Good Question. No PFD "Faults" that I can see. PFD Warnings on the Cpts and F/O's PFD's. (Flag: something quit), (Flag: Something else quit) But if the IRU's went off line???????? Uh Oh.

I happen to think you're correct on the messages preceding the fatal loss of control but that is slightly redundant in the sense that a broken airplane can't send any more messages, (as per GB's comment on the fin), so what it DID send becomes extraordinarily important.

Yeah I know. You're probably right. But what's really stumping me, is: Can't a spiraling bus transmit a cabin decent ADVISORY out on ACARS through HF? I mean ACARs doesn't know it's in deep doodo. Power should have been good. HF should have been good down to break up (VS fin loss) or dual flame out. Right? Really high G's don't come till the attempted pull out?

Now we just need an Air France guy to confirm they have the HF ACARs augmentation option, and as you and Interfug said we need confirmation of any more messages from French TV2.

We need more leaks.... :E

.

[CharlieBrem]

With reference to the Sky news report on possible terrorism, here are the facts: Sky and other British media have merely picked up and embroidered a short unsourced report that appeared yesterday on L'Express news magazine site (www.lexpress.fr (http://www.lexpress.fr)). This said that two Arabic names on the AF447 passenger list were similar to those of two suspected jihadists who are on the French intelligence watch list. The French report pointed out the high chances of simple coincidence. In other words, British media exaggerating again....

[BOAC]

While we wait (hopefully) for the FDR/CVR is it possible for someone ?!WHO KNOWS!? to summarise what can be deduced from the 24 ACARS messages we have seen? Perhaps the best place would be the Tech Log thread for this. At the moment we seem to have disputes over the meanings of the various warnings. A clear indication of the most likely sequence of events would be of interest.

I (briefly) saw a reference on one of the 3 threads to what must be preliminary autopsy reports and referring to Wiki, but I cannot find that now. If I saw correctly, some of the findings were a little surprising (to me). Anybody any more?

The Sky News report from Brian M is interesting and might cause folk like 411A to take a breath.

[nsxtasy]

BOAC:
I (briefly) saw a reference on one of the 3 threads to what must be preliminary autopsy reports and referring to Wiki, but I cannot find that now. If I saw correctly, some of the findings were a little surprising (to me). Anybody any more?



I believe this was in reference to the other plane crash that contributor was referring to (post#997 Air India 182). There is nothing reported anywhere regarding the state of the recovered bodies for AF447...just that they have been transferred to Recife and that the Brazilian teams sole job is recovering more.

[hawker750]

The scenario nsxtasy illustrates is IMHO quite feasable. What would be interesting to find out, but probably impossible, is who was on the flight deck?
It was a heavy crew so it is likely that one crew member was in the bunk. Was it the Captain? Where is the crew bunk on a 330? If nsxtasy's scenario had to be sorted by the first officer and a relief pilot chances of success are reduced.

[poison]

Bobrun,

I fully understand what you are saying and I am well aware that in Alternate law 2 that load factor protection is available. However this test was carried out several times with simulator engineers on the IOS.

Anyone who has access to an A330 sim should be able to replicate this. As mentioned after the aircraft breaks up and the visual goes red, the load on the IOS shows around +8G and the SD at +5.

[nsxtasy]

hawker750:
The scenario nsxtasy illustrates is IMHO quite feasable. What would be interesting to find out, but probably impossible, is who was on the flight deck?
It was a heavy crew so it is likely that one crew member was in the bunk. Was it the Captain? Where is the crew bunk on a 330? If nsxtasy's scenario had to be sorted by the first officer and a relief pilot chances of success are reduced.


Nope...I haven't illustrated any scenarios...you may be referring to "poison's" post.

[Brian Abraham]

From AVweb today

Air France Speeds Airbus Pitot Replacements After Pilots Complain

Air France has accelerated its effort to replace pitot tubes on its Airbus aircraft after members of one pilots union threatened to refuse to fly the unmodified airplanes, the New York Times reported on Tuesday. The airline had said over the weekend it would replace the sensors on all Airbus A330 and A340 airplanes over the next few weeks. But on Monday, Alter, a union representing about 12 percent of Air France pilots, posted a notice on its Web site urging its members to "refuse any flight on an A330/A340 which has not had at least two pitot sensors modified," according to the Times. SNPL-ALPA, which represents the largest share of Air France pilots, made no such suggestion, but union spokesman Eric Derivry told the Associated Press: "What we know is that other planes that have experienced incorrect airspeed indications have had the same pitots. And planes with the new pitot tubes have never had such problems."

A U.S. Navy ship and the French nuclear attack submarine Emeraude are both en route to the crash site of Air France Flight 447 to aid the search for the cockpit voice and flight data recorders. The Navy also flew two devices called Towed Pinger Locators to Brazil on Monday. The five-foot-long devices can detect the signals from emergency beacons from as deep as 20,000 feet. They will be towed behind French tugboats. Crews so far have recovered 28 bodies from the crash site. They have been flown via Blackhawk helicopter to Fernando de Noronha, an island 400 miles off the coast of Brazil, and later will be taken to the mainland in a C-130. Identification by fingerprints and dental records is expected to take some time. A total of 228 people died in the crash. On Monday, the airplane's vertical stabilizer was recovered, the largest piece of the aircraft that has been found so far. The piece showed no evident signs of fire or explosion.

[Interflug]

The scenario nsxtasy illustrates is IMHO quite feasable. What would be interesting to find out, but probably impossible, is who was on the flight deck?
It was a heavy crew so it is likely that one crew member was in the bunk. Was it the Captain? Where is the crew bunk on a 330? If nsxtasy's scenario had to be sorted by the first officer and a relief pilot chances of success are reduced.How much experience of hand flying the plane at altitude in alternate law in a stormy night without (reliable) instruments would the pilots of an A330 have
a) in simulator?
b) in real world?

I'm not questioning their ability. I'm questioning, if statistically it would make much difference who handled the plane. And one F/O had more experience on type than the captain.

AF press release Nr. 2: ...The flight captain had a record of 11,000 flight hours and had already flown 1,700 hours on Airbus A330/A340s.

Of the two first officers, one had flown 3,000 flight hours (800 of which on the Airbus A330/A340) and the other 6,600 (2,600 on the Airbus A330/A340).

[BOAC]

I believe this was in reference to the other plane crash - thanks - on a re-read I (think) I can see that now.

[arrffaa]

I couldn't agree more with DC-ATE post of 6th june.

More and more we, as Air traffic Controllers, are being sunbjected to the computer. Electronic flght progess strips, conflict alert when there isn't any, AMAN working out false and stupid EATs, computers telling us when to turn you on to the base and closing headings. Flashing that, coloured this, you can't do that, you MUST do this - all by a machine!

My brain works quicker than any computer when it comes to actually doing stuff. Let's keep computers simply for monitoring eh?

This is one of the saddest and most frightening accidents I have ever read about. I really hope that the FDR and CVR can be found. However, after the Concorde accident report, I also have MANY doubts as to the accuracy of the future BEA report, whether they are found or not.:sad:

[hawker750]

The point is that the Captain is more likely in his 11,000 hours of being caught in a monster before and to have reacted correctly. As has been said before 3 degrees works but you have to ignore height loss/gain. If the 2 F/O's had never experienced this terror before it makes it more difficult to envsage a sucessful outcome. I have been in the middle twice and as anyone who has experienced it, it is frightening, not only the violence but the noise. One really questions the integrity of the airframe

[etsd0001]

We do all understand the differences between ACMS, CFDS, CMS and ACARS don't we.

ACMS is system monitoring, not directly related to the CMS

CFDS is A320 speak for the CMS

CMS is A330/40 speak

[Graybeard]

Cap'n Crunch: "Yeah I know. You're probably right. But what's really stumping me, is: Can't a spiraling bus transmit a cabin decent (descent?) ADVISORY out on ACARS through HF? I mean ACARs doesn't know it's in deep doodo. Power should have been good. HF should have been good down to break up (VS fin loss) or dual flame out. Right?"

FWIW, The ACARS MU, Management Unit, is powered by 115 vac. I don't know which electrical bus on the A330, but it wouldn't be high priority.

I came to understand from prior posts that the ACARS was transmitting via the Satcom, and not HF. It would be tough for a spiraling plane to keep lock on a satellite, whereas the HF wouldn't much care. Why have both capabilities? Message cost on HF is lower.

GB

[SaturnV]

BOAC, the post mortem summary for bodies recovered from Air India 182 can be found starting on p. 19 of this report:

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

The mapping of recovered bodies to assigned seats (recognizing that passengers may change seats once airborne) indicates that the further aft a passenger was seated, the higher the percentage of body recovery. No bodies were recovered from the most forward sections of the 747. Also, few of the Air India recovered bodies showed evidence of significant trauma from having seat belts fastened. (That's not likely to be the case of bodies recovered from AF 447.)

A similar mapping of trauma and seat location was done for the victims of TW 800.

[BOAC]

Hawker - you claim to have been "in the middle twice" - are you seriously suggesting that you or anyone would NOT be in the left seat in the ITCZ as it was? .......and, incidentally, it will be EXTREMELY easy to determine who was where if we ever get the cockpit section back. I my opinion this line of questioning is a complete distraction.

[Graybeard]

Further to post above regarding ACARS message routing, Satcom or HF. The lat/long of the last transmission was provided in the listing. That should have been part of the preamble of every satcom message, showing where the beam was pointing, whereas I believe it would not be part of an HF ACARS preamble.

I've been going blind looking for the most accepted raw picture of the stream of ACARS messages. Does anybody have a quick link?

Thanks,
GB

[Safety Concerns]

can we keep this sensible.
You have a confirmed message from the crew that they were in turbulence.
You have released acars messages confirming a serious of faults.
You have an aircraft fitted with pitot probes that have been confirmed to cause problems in certain conditions.
You have weather reports confirming that those conditions were in that very area at that very moment AF447 flew by.
The acars messages confirm air data issues on an aircraft flying with known dodgy probes in an area with known bad weather that night.

What does it take for some people.

[flying brain]

The Sunday Herald
Key figures in global battle against illegal arms trade lost in Air France crash

Claims such as this are common in the period after the passenger list has been released and before any technical evidence emerges.

A week or so after the Lauda Air B767 300ER crash, caused by uncommanded reverser deployment, a passenger involved in anti drugs activities was identified and headlines appeared along the lines of the Sunday herald claims.

The Family was called by the press and asked how they felt that their relative was responsible for the death of 228 people. It was appalling.

Once the final facts emerge, everyone has forgotten the other claims........

[gilot]

http://www.sita.aero/file/1124/AIRCOM_Coverage_Maps.pdf (http://www.sita.aero/file/1124/AIRCOM_Coverage_Maps.pdf)
for all

[TripleBravo]

Lost in Saigon,

if the expert talking here: Innovation Analysis Group (http://www.iag-inc.com/premium/) is not talking about the CAB PRESS advisory, then I would refer to him as a real expert. ;) (Had no time to actually watch the video.)

It appears he was not given all the information that is available. If not, where does all the talk of "Cabin Vertical Rate" originate?Simple: Because this is the interpretation the audience wants to hear. You know, yellow press is telling what touches people, so does PPRuNe. Steep dive? How scary, yet sensational.

In reality, the last message is simply stating that something is wrong with the measurment of cabin pressure. It does not specify what exactly. It will be sent just as well when one of the sensors is wrong. One of the sensors this message is relying at is one of the ADIRUs - which were erroneous, as we know. => Faulty ADIRUs are enough to trigger this advisory.

More in-depth here: http://www.pprune.org/tech-log/376345-air-france-a330-accident-3.html#post4982977

[Graybeard]

Bloomberg.com has a fresh set of articles on the crash, and updates to prior articles. Their reporting seems credible.

GB

[Junkers388L]

A bomb would be the only way of explaining the lack of even a brief mayday on behalf of the pilots.



Bingaling, this is jumping to a conclusion and irresponsible speculation.

The facts are, to the best of my knowledge:

No mayday call (or other voice communication indicating problems) by AF447 was received by anyone after 2:10Z on June 1st.

This does not necessarily mean no transmission was made. Potential interpretations are (the list below does not claim to be complete):

Flight crew did not make an emergency transmission: e.g. because they stuck to the Avigate, Navigate, Communicate principle and tried to sort out the problems in controlling the airplane and dealing with system failures they had; flight crew incapacitation might be another reason (ref. Helios accident)
Flight crew made a transmission, but nobody received it: nobody was within range and tuned to the frequency they used, atmospheric conditions degraded or garbled their transmission
Flight crew attempted to make a transmission, but was unsuccessful: we essentially do not know what happened to the aircraft after 2:14Z, except that it crashed, so by the time they decided to make the call, systems/components required to achieve a successfull transmission might have been lost, ... (myriads of reasons)ONLY the CVR (if ever recovered) can give a conclusive answer as to whether the flight crew attempted to make an emergency transmission or not!!!

Edit: As thankfully pointed out by "forget" and "Graybeard", the FDR also records mic keys, i.e. one would be able to see whether the crew made attempts to transmit a message over the radio (and I think even if it was the CPT or F/O).

[CONF iture]

Safety Concerns, fully agree with your post, except for one point :
You have a confirmed message from the crew that they were in turbulence
What is your reference to write that ?

[wes_wall]

Bobrun
The full report is available online, for those who can read French. The description of the warnings they received are very similar to those apparently received by the AF crew, so a parallel can easily be drawn

Would you mind posting a link. Thank you

[Jetstream67]

The received ACARS messages are clearly facts as the system saw it.
That some or all came via SAT - suggesting power and a 'fairly' steady/level antenna as they were sent some minutes after the start of the incident seems to be a fact. Other /later messages may presumably have been generated but never actually sent if/as this changed.

The lack of HF /VHF messages appears to be a fact

The flightplan, no notified diversion, and passing through the CB at night over water appears to be fact

The challenges of the ITCZ generally are a fact

The known pitot tube issues appear to be facts

The 'difficulty' of flight around the coffin curve with instruments not working is a fact.

We don't KNOW a lot else . .

Wandering off these facts to speculate about bombs and bermuda triangles and various similar (?) incidents may be 'human' but perhaps another thread called "unsupported theories" might be a better place for them ???

Just my new-boy penny-worth :-) . . better duck now !

[Gary Brown]

The link someone helpfully posted a while back to the Air Caraibe report is:

http://www.eurocockpit.com/docs/ACA.pdf

It’s an internal Air Caraibes discussion document dated December 2008, and issued by their Flight Safety Manager. It refers to two near-identical incidents in August and September of 2008, each one happening to a different A330-200 in the fleet. It then goes onto describe in detail one of those incidents, the case of F-OFDF operating from Martinique to Paris. Note that it doesn’t say where these incidents occurred, nor give more than bare details of the weather encountered.

It’s clearly a scan of a photocopy of the document (and therefore not an “official release” by anyone), and is in 8 sections. Most of those sections are effectively in English, and they go through in detail the instrumentation displays, alerts and checklists which are all given in “Aviation English”, as are all the diagrams. The sections are (I’m translating here):

1 – Avoidance of the area of turbulence

2 – Application of the procedure “SEVERE TURBULENCE” QRH 5.01

3 – Icing of the probes

4 – Reaction of the flight crew

5 – Analysis of the events and their consequences

6 – “RESETS”

7 – Modification of the “PITOT” probes

8 – Meeting at “AIRBUS”
[my note: this meeting is about conflicts between alerts and checklists, especially relating to “STALL”]


My own sense is that only the very beginning of the document really requires that you read French, so here’s my translation [btw, everything in CAPITALS is in capitalized English in the original]:


Dear Colleagues,

At the end of August and the beginning of September our two Airbus A 330-200s ran into severe icing conditions. The causes and consequences were near-identical. Please find below a detailed account of the flight of F-OFDF between Fort de France and Paris Orly.

Phase 1 - Avoidance of the area of turbulence

At 2211hr “HDG” mode was selected on the “FMA”. At 2212hr, as the “WEATHER DEVIATION PROCEDURES FOR OCEANIC CONTROLLED AIRSPACE” was adopted, the crew climbed from 35000FT to 35300FT. This gain in altitude of 300FT did not produce any improvement in flight conditions. As a result, at 2214hr the crew decided to descend, and again stabilized at 35000FT.

Phase 2 - Application of the procedure “SEVERE TURBULENCE” QRH 5.01

At 2222hr + 9s, as the “SEVERE TURBULENCE” procedure was applied, Mach was reduced to M0.80 and the “A/THR” was disconnected. As a result of the weight of 206T and FL350 the “PF” then adjusted N1 to between 81% and 82%.

Phase 3 – Icing of the probes

From 2222hr + 20s to 2222hr + 36s the “TAT” rose from -14deg Celsius to -5 deg Celsius. This rise in overall temperature is a previously seen symptom when severe icing conditions are encountered. The value of the “TAT” in fact reflects the build-up of ice on the probe.

From 2222hr + 36s to 2223hr + 00s the “TAT” maintained a constant value of -5 deg Celsius. ………….
From here on anyone who understands “Aviation English” should be able to follow the text quite easily.


AGB

[rgbrock1]

Disclaimer: I am not involved in any aspect of flight aside from being on occasional SLF.

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

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

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

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

Thanks.

[forget]

Junkers388L. ONLY the CVR (if ever recovered) can give a conclusive answer as to whether the flight crew attempted to make an emergency transmission or not!!!

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

[Dani]

Captainflame, can you give me the link for the Air Caraibe incident? I don't mind reading in French.

Thanks,
Dani

[Safety Concerns]

the confirmed turbulence message was reported by Brazilian ATC as mentioned during the last radio contact.

I may have to take that back as "confirmed" as I also can no longer find a reliable source. Unfortunately no time now will come back to it though.

[Graybeard]

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

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

GB

[fg32]

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

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

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

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

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

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

My suggestions

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

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

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

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

Count to ten before hitting "reply"? Pretty please ?

[TripleBravo]

ELAC, as to

@ 210T and M.80

Optimum Altitude = FL360
Max. Alt. @ ISA+20 = FL370
Max. Alt. @ 1.4G Margin = FL378
Max. Alt. @ ISA+10 = FL385
Max. Alt. @ 1.3G Margin = FL394the numbers for AF447 / MSN660 are slightly different (lower MAX ALT):

http://img189.imageshack.us/img189/9929/qrh409.th.png (http://g.imageshack.us/img189/qrh409.png/1/)

[Captain Bob]

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

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

Actually Parabellum you were quite correct. The SIC was flying AA 587 when it went down, not the Captain. This may be a repost however. Could of responded earlier but there are several hours difference over here on the other side of the pond.

[Hiflyer1757]

Concerns Over Recovering AF447 Recorders | AVIATION WEEK (http://www.aviationweek.com/aw/generic/story_channel.jsp?channel=comm&id=news/RECORD060309.xml&headline=Concerns%20Over%20Recovering%20AF447%20Recorders)

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

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

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

[PapaEcho]

Muhaha S.F.L.Y. your are right!

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

Cheers,
PapaEcho :ugh::D

[Junkers388L]

Graybead, PJ2

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

Graybeard's TCAS analysis brought me on this track.

Don't have access to the A330 AMM, therefore can't decode (below ATA chapter level) what the 2:14Z error code means in detail.

[hawker750]

BOAC

What I was suggesting is that it is a possibility. In my career when I was a first officer (BOAC) I have operated in heavy crew situations where the captain indeed would go back to the bunk with instructions of not to be disturbed unless absolutely necessary. If the crew thought they could penetrate the line they may not have disturbed him. What followed next probably precluded him coming up anyway. And there are certain pilot types who would prefer not to disturb him on principle. It is dangerous to disgard a possibility just because it it not something either I or you would do

[PapaEcho]

Junkers,
the last message was a Pressurization Controller Fault as stated by A330 AMM...which can means both of your theory. I'm propending for the Pressurization Controller erroneus input by ADIRU.

PapaEcho

[avspook]

"The ACARS also contains protocols to support retry of failed messages or retransmission of messages when changing service providers."

Interfug asked if it's a complete list, So: How often does it retry? We know it got off what? 27 total faults and warns (including 3 mtc status wrns) for four minutes straight, so the acars system had normal DC and was functioning. I don't see how there could be any missing messages between 0210 and 0214z since ACARS breaks the info up into blocks (where's AVspook?, he probably knows the answer to this) This is the world of data bits and verification and secondary resends: only a real "TRON" can verify that when it's got a lock it's streaming fast. Wiki only says:

Its can be programmed for number of retries - This is the VHF ACARS they are talking about, on some AB's will ahve a dedicated provider eg SITA however you may alos have the option to swicth to another provider (Arinc) however it will keep interrogating the SAT until it offload its message.

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


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

at the Maintenance center for both Boeing (Aircraft Health Management option) and airbus (AirMan Option) the messages will pop up allowing access to order parts send repair info to the arrival station while the aircraft is in flight. The LAT/LON of the aircraft also used to show on the screen and on the AirMan option you could view a realtime globe of your fleet

[avspook]

Good description can be found here

http://www.iaa.ncku.edu.tw/board/upload_disquisition/20061101112816Recording%20System-present01.pdf

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

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

Note If The recovery teams can get the QAR they will have far more data than is presented on the FDR - If AF had the QAR option

[Ground Brick]

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

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

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

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

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

[DorianB]

10/06/2009 - 10h34
Press Release- English
PRESS RELEASE 23

INFORMATION ON THE SEARCH FOR AIR FRANCE FLIGHT 447

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

NAVAL SOCIAL COMMUNICATION CENTER
AERONAUTICAL SOCIAL COMMUNICATION CENTER

[DorianB]

The English text below is an automated translation of the press release at the bottom (as officially distributed):


Translation: Portuguese » English

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

Federal Police and Department of Social Defense of Pernambuco

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

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

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

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

By: Federal Police and Department of Social Defense of Pernambuco

Tel: (61) 2024-8142




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

Polícia Federal e Secretaria de Defesa Social de Pernambuco

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

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

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

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

Por: Polícia Federal e Secretaria de Defesa Social de Pernambuco

Tel.: (61) 2024-8142

[abkasti]

Quote:
You have a confirmed message from the crew that they were in turbulence

What is your reference to write that ?
:: FAB - Força Aérea Brasileira :: (http://www.fab.mil.br/portal/capa/index.php?mostra=3085)

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

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

At 02h30 (de Brasília time), the Recife SALVAERO triggered the search for the means of the Brazilian Air Force - FAB, with 01 C-130 Hercules aircraft, 01 P-95 Bandeirante for maritime patrol and rescue squad Aeroterrestre (Paras)
"
"de Brasília time" do they mean Paris time?

[cesarnc]

@DorianB


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


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

[Graybeard]

Of course we don't really care that the TCAS failed with no other traffic within range. What I am pursuing is what failure triggered its fault report. I found the below list on the Italian page. Can you point me to a better list?

The first four items would follow from iced pitot tubes, where there would be airspeed disagree. Airspeed anomalies should not affect altitude computation enough to cause the digital Altitude word to go Fail Warn out of the ADIRU. And airspeed will not affect pitch and roll outputs.

The TCAS depends on Altitude, not airspeed.

The IR faults are down the list, obviously occurring some time after the TCAS Fail. Moreover, if 447 had Collins TCAS, IR Fail would be meaningless anyhow, as the Collins doesn't use pitch and roll inputs. Honeywell TCAS use those inputs, but might not fail itself if those inputs are failed.

ATA 27.91 F/CTL ALTN LAW
ATA 22.83 FLAG ON CAPT PFD
ATA 22.83 FLAG ON F/O PFD
ATA 22.30 AUTO FLT A/THR OFF

ATA 34.43 NAV TCAS FAULT

ATA 22.83 FLAG ON CAPT PFD
ATA 22.83 FLAG ON F/O PFD
ATA 27.23 F/CTL RUD TRV LIM FAULT (Brutta cosa)
ATA 34.11 EFCS2 EFCS1 AFS FAULT
ATA 27.93 EFCS1, EFCS2X FAULT
ATA 22.83 FLAG ON CAPT PFD
ATA 22.83 FLAG ON F/O PFD
ATA 34.10 NAV ADR DISAGREE (ADIRU DISAGREE)
ATA 34.22 ISIS 1, ISIS 2 FAULT (22FN)
ATA 34.12 IR2, EFCS1X, IR1, IR3 FAULT
ATA 27.90 F/CTL PRIM 1 FAULT
ATA 27.90 F/CTL SEC 1 FAULT
ATA 22.83 AFS 1, FMGKC1 (1CBS2)
ATA 21.31 ADVISORY CABIN V/S
------------ END OF TRANSMISSION------------

I believe we can rule out icing of the pitot tubes as cause for TCAS Fail, and we can rule out attitude, as the TCAS Faults came before the IR Faults.

We are left with a few possibilities, one being a TCAS antenna.

Another possibility is Altitude Fail, but that does not appear so early in the reporting, if at all.

Sure, severe turbulence could trigger a TCAS Fail in an intermittent installation, and I would be looking at the airplane's history for that.

Otherwise, I'd be looking for lightning damage, rare as it may be at that fright level.

GB

[augustusjeremy]

Great Work Greybeard! The HF was most likely operational until 0214z (we say this, because of the absence of a LRU ACARS message of it being faulted). Therefore, the vertical stablizer was intact and had not left the airplane before 0214z.

This Means that the ACARS messages probably preceded the fatal loss of control event.

Does the HF antenna provide an specific input for fault detection or the lack of the HF antenna would be detected by the absence of (constant and periodical) inputs in a given buffer outside the rudder ?

[einhverfr]

I have a closely related question:

How much is known about the processes by which pitot tubes ice up at altitude? I have read a number of other reports which suggest that the culprit is not liquid water (or at least do so to me since pitot tube icing is the only icing mentioned, and in at least one case, ice crystals and graupel were reported at FLs 180-310, while icing if pitot tubes occurred at FLs 390 and 410).

Is it possible that the ice crystals deposit and fuse inside the tubes, thus obstructing them? Of am I missing something major?

[DorianB]

Lav door:



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

[Robin42]

Starting in 2008, Air France is said to have offered a GSM-based service named "Mobile OnAir" to their passengers, which had allowed to use a cell phone during flight, at least on an experimental base. For obvious reasons, I'm interested to know if this service had been continued until today, in particular, if AF447/F-GZCP had an active, satellite linked GSM basestation installed.

[jimpy1979uk]

Ground brick,

You've stated that HF is not an option for data transmission but on the latest HFDR(high frequency data radio) equiped aircraft data transmission by the ATSU is indeed possible.

This aircraft technically didn't have a ACARS system instead it had a ATSU which acts as a router of data from the FMGEC, CMS or FIDIMU to the VDR(VHF data radio), SATCOM or HFDR depending on selected customer options.

The hardware functions of a ACARS CMU are carried out by the AOC software in the ATSU.

[maynardGkeynes]

Correct translation would be "where legal medical examinations will be carried out".I would translate as "forensic examinations."

[Rananim]

I read through the Air Caraibe report despite poor French.One thing that stood out for me:
"En effet,le PF est intimement persuade que les deux alarmes "STALL" sont inappropriees."
ie.the pilot relied on instinct/airmanship by ignoring the false STALL alarms.
The report seemed to imply that it was a good thing that the crew couldnt read the TECH RECOMMENDATIONS in the turbulence,because they would have directed the crew to respect the alarms,as already discussed by Bobrun.

The report spoke of an environment that was "extremement charge" due cacophony of aural alarms.They focused on "flying the plane" and reading the UNRELIABLE AIRSPEED checklist and here I lost the translation a bit but it seemed to say that having disengaged ATHR and set turb N1 prior to the crazy airspeed readings(they encountered turbulence earlier),they were already at an advantage.They were already in a state of preparedness and so could " renforcer son attention sur sa trajectoire et sa vitesse"(fly the plane).Only speed reference was GPS.

"Never in the field of PPRUNE boredom has so much speculation been based on so liile facts"

This (and the previously closed thread) make the speculation about BA038 seem restrained.

Nobody died on BA38.Contribute or shut up but dont denigrate.

[Flyinheavy]

@Rananim:

"En effet,le PF est intimement persuade que les deux alarmes "STALL" sont inappropriees."
ie.the pilot relied on instinct/airmanship by ignoring the false STALL alarms.In fact the PF was truly convinced that the two alerts "STALL" are false

[TyroPicard]

Greybeard, Safety Concerns

Request for clarification..
Greybeard posted this on the previous page: ATA 34.12 IR2, EFCS1X, IR1, IR3 FAULT.
I originally thought this meant failure of all three IR, an assumption I made several days ago, but I also remember reading that the "EFCS1X,IR1,IR3" bit refers to the equipment reporting the fault, which in this case is entirely logical. This would imply that IR1 and IR3 were not reported as failed.
So is IR2 the only IR to be reported failed?
Thanks, TP

[wes_wall]

Tripple Bravo two pages back (1088) posted a link to visit. This was from that site, and may be helpful to some.


http://www.iag-inc.com/premium/acars2.pdf

[deSitter]

Those who imagine the tail separated on impact must realize that the plane would not "sink" but be fragmented into thousands of small pieces, with a massive region of floating paper, insulation, and all manner of debris, intermixed with fuel, oil, and hydraulic fluid, some of which would be deposited on the surface of the tail section - we know this looks clean as a whistle and was found off by itself - making it almost certain that the tail separated well above the main wreckage site.

I would then propose an alternate theory - from the visible damage to the tail section's lower region - the presence of middle and rear mounting boxes that have been torn from the empennage structure - perhaps the front mounting lug failed, allowing aerodynamic forces to lever the tail backward just enough to allow 500+ MPH air to penetrate into the body of the tail section - this would probably be enough to pry the tail section from the empennage and cause the visible damage to the lower part of the rudder, and would also result in the obvious torqueing seen on middle and rear the mounting boxes that remained attached to the tail section. The front mounting lug is missing in just the same way seen on AA587. This would also explain why the rudder remained attached to the tail section with no evidence of excessive sideways force being applied to it.

-drl

[vapilot2004]

Lost in Saigon,

if the expert talking here: Innovation Analysis Group (http://www.iag-inc.com/premium/) is not talking about the CAB PRESS advisory, then I would refer to him as a real expert. ;) (Had no time to actually watch the video.)


The expert quoted here has little or no Airbus knowledge.

[syseng68k]

Hi,

New here, but may be able to contribute something.

HF Antenna: The state of this would be reflected in the vswr reading, which essentially says how well the transmitter is matched to the antenna. If the antenna is missing, or cable open circuit or shorted, the transmitter autotune would detect it and either run at reduced power or shutdown completely.

Whether this would result in an ACARS message, someone else may know, but it is detectable and should be logged...

Regards,

Chris

[vapilot2004]

While we wait (hopefully) for the FDR/CVR is it possible for someone ?!WHO KNOWS!? to summarise what can be deduced from the 24 ACARS messages we have seen?

Much earlier in this thread I have with the help of a retired A330 engineer posted the following decoded maintenance computer ACARS messages:

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

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

The above from my post 6 Jun here. (http://www.pprune.org/rumours-news/376433-af447-post4977863.html#post4977863)

Two more required expert interpretation as they can have multiple meanings:

The Rudder TRV Lim Fault at 210Z (code 2723) is a reported fault by the flight control primary/secondary computers and is probably related to the loss of ADIRU air data. This is not solid, but likely and is also a known and expected fault message as any other failure of the rudder limiter would have been followed by additional failure or warning messages.

I have mentioned this before on this thread and discounted "Daryl's" Honeywell 'expert' (http://www.pprune.org/rumours-news/376433-af447-post4985889.html#post4985889) interpretation of this message.

The 214Z advisory warning (code 2131) could have been one of the following:

Cabin Vertical Speed, Cabin Altitude, Differential Pressure or cabin pressure controller data loss (lack of pressure info, TAT or mach data from the ADIRUs). When there is a loss of ADIRU air data, the cabin pressure controllers will pass the same code without extensions. The first two advisory messages (vs and Cab Alt) would be accompanied by other faults so this is most likely to have been a warning about the Delta P (descent rate being too high) or a general cabin pressure controller fault. Again not solid, but the last two ACARS received code interpretations are the most likely scenarios.



Finally, the least glamorous 2245Z maintenance status (code 3831) message is related to the vacuum system controller for the toilets. This could be a potable water or waste tank level, tank differential pressure, or general toilet (unassigned) fault.

[BOAC]

Thanks, va, but I am looking to see what can be reasonably deduced from the messages in terms of systems degredation. As little supposition as possible? EG are we CERTAIN the initial warnings came from 3 failed pitots as seems to be the baseline here, or could we be looking at software rather than hardware??

[vapilot2004]

Boac, yes, well in that case, only these two:

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

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

fell into the definite bin.

These results were passed along via an exchange of emails so I will try a prearranged phone conversation to see what else can be made more solid in the list.

[eliptic]

Finally, the least glamorous 2245Z maintenance status (code 3831) message is related to the vacuum system controller for the toilets. This could be a potable water or waste tank level, tank differential pressure, or general toilet (unassigned) fault.


Maybe the A/C flying up side down giving that status:eek:

[ttcse]

Apparently they've now recovered over 100 pieces of debris.

[eliptic]

Pure speculation from me, but I see the Captain in his bunk, the F/O's putting the a/c in a big Cb, probably due to botched (if well intentioned)attempt to navigate around them on their own without waking him.

Why so many have a concern were the Captain did sleep or whatever? as i understand the 2 F/O was highly qualified for the A/C

[KC135777]

http://www.dcs.gla.ac.uk/~johnson/papers/ISSC09/ADIRU_Accident_Submission.pdf


The Dangers of Interaction with Modular and Self-Healing Avionics Applications:
Redundancy Considered Harmful
C.W. Johnson, Ph.D.; Department of Computing Science, University of Glasgow, Scotland.
C. Michael Holloway, NASA Langley Research Center, 100 NASA Road, Hampton, VA, USA.

[Will Fraser]

pth

I understand your advice, do you understand you are seemingly suggesting it to an autopilot? As I understand it, at least until 0210, tha a/c was under control with a/p flying. The involuntary disengage is reported at that point, and for four minutes no conclusive data to prove what was going on. Tha a/p may have disconnected because it couldn't accomplish what you are demanding: nose @ horizon, wings level, turb pen. speed, etc. What exactly do you mean by "what has happened to us as pilots?"

Will

[JD-EE]

syseng68k (http://www.pprune.org/members/302789-syseng68k)

HF Antenna: The state of this would be reflected in the vswr reading, which essentially says how well the transmitter is matched to the antenna. If the antenna is missing, or cable open circuit or shorted, the transmitter autotune would detect it and either run at reduced power or shutdown completely.

This may depend on the transmitter being keyed to detect it. On receive there is generally not enough power available anywhere to run a VSWR bridge to detect the mismatch from a disconnected antenna.

These days a missing AMU, antenna matching unit, would probably be noticed. The transmitter would probably maintain communications with the AMU as a health check. In the bad old days I've had my fingers upon there was no such knowledge in the transmitter until you tried to use the AMU, as when the transmitter keyed.

{^_^}

[Gringobr]

exames médicos legais are autopsies
One could think of it as legal medical exams, where legal means a medical exam that has to be legally done ( as in cases of unusual deaths)
Note autopsies are not legally required in Brazil, although often done

[DC-ATE]

Will Fraser -
What exactly do you mean by "what has happened to us as pilots?"

I think that what -protectthehornet- means (correct me if I'm wrong PTH), is that you don't want the auto-pilot and/or auto-throttles engaged in those conditions. HAND FLY the aircraft!! BTDT.

[ClippedCub]

allowing aerodynamic forces to lever the tail backward just enough to allow 500+ MPH air to penetrate into the body of the tail section - this would probably be enough to pry the tail section from the empennage

The airplane could fly with the fairings removed at max q and the dynamic pressure wouldn't remove surfaces. Will try to write a brief tutorial on aerodynamics in the tech section so as not to clutter up this section.

If the airplane was experiencing turbulence severe enough for the crew to phone home a report, then if the Captain was in crew rest, would think he'd make his way back to the seat.

[ttcse]

deSitterI would then propose an alternate theory - from the visible damage to the tail section's lower region - the presence of middle and rear mounting boxes that have been torn from the empennage structure - perhaps the front mounting lug failed, (then bad things happen)

Sure, if the front mounting lugs weren't doing their job bad things would likely happen. The question isn't so much how the tail would subsequently unravel in your scenario, but why the front mounting lug would fail in the first place.

You can't say the tail would or wouldn't have fluids on it, especially after being in the waves for a few days. An estimation of 'likely or not' doesn't matter either.

[stilton]

Eur Sam Client,


Deviation clearance, over the ocean ? if I am approaching an area of severe weather over the ocean and need to deviate before I get 'clearance' I will do so to whatever extent I need while putting out advisory calls to other aircraft
on oceanic and guard VHF frequencies, I have done so and will again as have many of us.


There is not a professional Pilot on this forum that would penetrate convective activity because they are waiting for 'permission' to avoid it.


I would do the same over land for that matter if I was unable to reach the controller in time.

[Bleve]

Why so indeed. You apply the 'Inflight Weather Deviation Contingency Procedure'. In short: if you can't get an ATC clearance in time and have to deviate around weather, you do. Transmit a PAN on guard and if the deviation is more than 10nm, climb 300ft if south of track, descend 300ft if north.

[Will Fraser]

The VS on 447 didn't part as 587's did. The likeliest explanation is that the Clevis/Pin points were strengthened as a product of 587's failure. Catastrophic failure isn't complex, it occurs at logical weak points. If the pins, web system of the 330 has enhanced structure, what's next? The next mating structure, in this case a combination of box/tower 'blocks', with their insertion into stringers, bulkheads, and decking.

The most probable origin of the energy was airflow impacting one surface of the fin/rudder at an angle that surpassed design load and then failure point. Laterally. Longitudinal failure I think is a far more remote possibility.

If the failure happened at altitude, and the VS/Rudder was resisting a yaw, the lack of controllability in this axis would cause a roll, and it is unlikely to have been recoverable. The a/c would then... well, most likely tumble. imo. sorry

[ClippedCub]

Tech log's not the place. Will make it compact.

Transport aircraft are demonstrated to an FAA FAR requirement that exceeds Vne at 1g. Flutter is a possibility, but simple structural failure is more likely. The WTC aircraft were flown well beyond Vne without flutter for example.

Mach buffet is not to be confused with flutter. It is merely flow separation on the wing due to stronger than normal shock waves, and is a function of lift and Mach number. It's operational limit is defined by the level of uncomfortable vibrations felt in the cabin, and is not destructive.

The tail is designed to a higher design Mach number than the wing, and is characteristic of thinner airfoil sections, and/or increased sweep so you have unhindered control to back out of buffet. Flutter wise, the tail is stiffer than the wing due to structural aspect ratio/stiffness, and the wing will typically flutter first.

fa-MD773ZAQ
ca4PgyBJAzM

Failure due to flutter could be considered less likely than encountering gusts at beyond Vne speeds. Even then, the wing would have load alleviating fuel in the tanks, so it could withstand more than you might expect. It's entirely possible that the weak point could be the horizontal tail. If it departed in a downward direction, it could peel that section of empennage with it, leaving the vert momentarally attached at the front.

Apologies if this is too long. Bin if desired.

[MG23]

Minimum SATCOM link bandwith is 16 kbps - all known ACARS data can be transmitted in 1 sec.

I believe ACARS via satellite uses 1-10kbps (approx) channels. High bit-rate channels don't make much sense for a system where you might have a few hundred aircraft sending a short message every few minutes... if you can't keep the channel full (e.g. 40-60% average load) then you're just wasting satellite bandwidth.

SATCOM modem also can take responsibility to repeat data, if not send propertly, so only 2:14z events data can be incompleted\not fully transmitted.

I suspect an incomplete message will be dropped at the ground station; the protocol will request retransmission a number of times if data gets lost between the aircraft and the ground, but eventually gives up.

[Captain-Crunch]

avspook said:
Its can be programmed for number of retries - This is the VHF ACARS they are talking about, on some AB's will ahve a dedicated provider eg SITA however you may alos have the option to swicth to another provider (Arinc) however it will keep interrogating the SAT until it offload its message.

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


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

at the Maintenance center for both Boeing (Aircraft Health Management option) and airbus (AirMan Option) the messages will pop up allowing access to order parts send repair info to the arrival station while the aircraft is in flight. The LAT/LON of the aircraft also used to show on the screen and on the AirMan option you could view a realtime globe of your fleet

This is very important. So, from your expertise, Behavior of ACARs transmissions is largely customer (airline) specific. Most airlines would avoid exclusive SAT transmissions unless they like big monthly bills. But in the mid-Atlantic, after the MU (or it descendent) gets tired of trying VHF (out of range) and then maybe HF, THEN it would reference it's spacecraft almanac and drive the Sat antenna to the GEOstationary sky coordinates and attempt to blow the whole message up at once. Right? Without a sucessful response from the Satellite, it will start over and attempt repeated interigations of the spacecraft, until it gets a response.

This is important because, if it is true (and I'm taking it on rumour that those coordinates were part of the message at 0214z), this means that the IRU portion of at least one of the ADIRU's was functional.

Why is this important, you ask?

Because if the crew had an IRU platform at 0214z, (and they had to for the ACARs to broadcast it's position to the Satellite), then they likely had Attitude information available to them.

This strongly suggests to me now, that the airplane was wings level at 0214z completely intact and flyable in Alternate Law with attitude information available. (This does not mean, by any means, that any pilot could have kept it right side up in that kind of weather system.)

CC

[grizzled]

Ladies and Gentlemen . . .

Most of the speculation here -- including many of the "informed" comments of professionals -- is simply "by guess and by golly" based on everything from google to gut feeling to real-life experience. At this stage even most of the best informed and best intentioned of posts should be treated the same as the genre we now call "creative non-fiction". In no case should anyone assume that what we have learned so far points with any degree of accuracy to the "cause" of this tragedy.

The best that we can hope for is that the recorders will be located, the data decoded, an informed report issued, and aviation safety thus further enhanced. I for one have a high degree of optimism that these things will occur in this instance.

Grizzled

[MG23]

Without a sucessful response from the Satellite, it will start over and attempt repeated interigations of the spacecraft, until it gets a response.

If I remember correctly, the aircraft isn't supposed to send anything unless it can sync to transmissions from the satellite at the correct frequency: in fact, I don't think it can since it won't know the correct timebase for the channel.

So I agree: the fact that it was transmitting implies that the aircraft had some kind of location and orientation information (I presume the beam steering unit gets that from the same system the crew would) and wasn't so unstable that the antenna couldn't lock to the satellite within the transmission tolerance.

[Captain-Crunch]

MG23:
If I remember correctly, the aircraft isn't supposed to send anything unless it can sync to transmissions from the satellite at the correct frequency: in fact, I don't think it can since it won't know the correct timebase for the channel.

So I agree: the fact that it was transmitting implies that the aircraft had some kind of location and orientation information (I presume the beam steering unit gets that from the same system the crew would) and wasn't so unstable that the antenna couldn't lock to the satellite within the transmission tolerance.

Thanks MG23 for the Sat correction. It must "see" a lock, then before transmission of data. (Man these techs are great.) (thanks also Grdbrk and others)

And apparently the vender is SITA not ACARs from ARINC like we are used to in the states? But it does essencially the same thing. I could only find this 1973 description of the SITA transmission times:

7.3 Response Time

The average response time for Type A messages, i.e. the time lapse between the Instant an operator presses the transmit key of his terminal to send his query and the instant the first character of the reply appears on the screen (see Figure 6) ranges from 1.4 seconds to 3 seconds, depending on the number of links involved in route. A typical response time distribution is shown in figure 9.

7.4 Satellite Processors

The downtime of SPs is around 16 hours per month including scheduled and unscheduled stops (e.g. preventive maintenance, configuration changes, etc.)

Presently, certain SPs switch up to 6 message blocks per second during peak conditions of traffic.

Switching times are in the order of 5 ms per block for both systems.


So the SITA/ACARS transmission is instant, once it gets a lock.

SITA NETWORK by Chretien, Konig & Rech (http://rogerdmoore.ca/PS/SITAB.html)

[Captain-Crunch]

vapilot said:
Much earlier in this thread I have with the help of a retired A330 engineer posted the following decoded maintenance computer ACARS messages:

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

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

The above from my post 6 Jun here.

Two more required expert interpretation as they can have multiple meanings:

The Rudder TRV Lim Fault at 210Z (code 2723) is a reported fault by the flight control primary/secondary computers and is probably related to the loss of ADIRU air data. This is not solid, but likely and is also a known and expected fault message as any other failure of the rudder limiter would have been followed by additional failure or warning messages.

I have mentioned this before on this thread and discounted "Daryl's" Honeywell 'expert' interpretation of this message.

The 214Z advisory warning (code 2131) could have been one of the following:

Cabin Vertical Speed, Cabin Altitude, Differential Pressure or cabin pressure controller data loss (lack of pressure info, TAT or mach data from the ADIRUs). When there is a loss of ADIRU air data, the cabin pressure controllers will pass the same code without extensions. The first two advisory messages (vs and Cab Alt) would be accompanied by other faults so this is most likely to have been a warning about the Delta P (descent rate being too high) or a general cabin pressure controller fault. Again not solid, but the last two ACARS received code interpretations are the most likely scenarios.


Great analysis. I'd really like to know if the SITA(acars) system "ADVISORY" is a really a warning. If it is a repeater of info on ECAM, most of these messages would be low-level Amber advisories. This means RED warnings like "CAB Altitude" could be ruled out. We need a SITA French mechanic to answer this for us. Can one of our French speaking guys copy this question to the french forum?

Cheers,

CC

[PJ2]

Grounded101;
In structured problem solving you don't discard data at this earliest step in the process, any theory can be constructed, theories are not discarded at this stage, no matter how improbable, as it is too early to attempt to reach a conclusion
- Specific knowledge and experience of a situation often constrains thinking
There are a lot of highly-experienced, skilled people contributing here including accident investigators, trained human factors people, flight data people, systems engineers & analysts, manufacturers and even a few who actually have designed the systems now under present discussion and who have examined this and all the other ACARS messages. This much is a given.

While at this point much more is possible in terms of explanations than that which may reasonably be ruled out, we know that the VSC (Lav) message bears no import or even a hint at what went wrong. Many of us know this airplane well - the "LAV" acars message is a common maintenance message, occuring on practically every flight for some unknown (to us) reason. It shows up on practically every post-flight ACARS/AIMS Report along with a few other Class II (non-flight crew) messages.

While it applies to this flight, this system and this message indicate nothing untoward with regard to pressure bulkheads, tail-issues, impending failures, etc etc etc. This has been stated a number of times in this and the first thread.

While almost all would agree with the statement regarding improbability, early conclusions and dismissable evidence early on, (because these investigation fundamentals are well understood by many, though clearly not all, here - (not referring to you specifically), let me turn your point around and ask the question, what do you do with items/facts that are both well-understood and known to be irrelevant? At what point does one dismiss factors? I suggest that point was reached with this message a very long time ago, and reasonably so.

The nature and cause of the "lav" message is known as is the system. If we are, after more than a week of thrashing about, to take the position that all is admissable, then we'll be swatting flies for another few thousand posts, while the investigators, even without the recorders, will have ruled out some fundamentals.

I intend this to be respectfully helpful to you and to anyone who may believe that individual threads make an entire suit. I am trying to educate generally; No one is exploring the possibility, given all else before us.

Further....
We don't even know if the ACARS messages are in the correct order. BITE (built in test equipment) within the system controllers may have delayed a fault message while internal system self-testing was going on, only to latch to the fault/failed mode after other, more swiftfly-reporting systems have been captured by the ACARS. This is a maintenance system and not a flight data tool, after all.

It still cannot be said if the ultimate reason(s) will be complex as in the Pitot-TAT/warm air followed by a loss of control theory, or straightforward as in "they flew into a thunderstorm and broke up" theory.

respectfully,

PJ2

CC, vapilot - here are the 24 failure flags which may show up on the PFD:

http://i277.photobucket.com/albums/kk76/batcave777/pfd_flags_2009-06-07_101322.jpg


1. ATT flag (red)
If the PFD loses all attitude data, its entire sphere is cleared to display the ATT flag.
2. CHECK ATT or CHECK PFD or CHECK PFD1 (or 2) flag (amber)
“CHECK ATT” appears when there is a disagreement (of a least 5°) in the attitude information
displayed by the two PFDs. The CHECK ATT flag appears on both PFDs, and a caution appears on
the ECAM.
“CHECK PFD” appears when the DMC detects a disagreement between the two PFDs. The CHECK
PFD flag appears on both PFDs.
“CHECK PFD 1(2)” appears when the DMC detects a disagreement between its own computation and
its displayed information. The CHECK PFD 1(2) flag appears on the relevant PFD.
3. SI flag (red)
If the sideslip information is lost, the index disappears and a red SI flag appears.
4. FPV flag (red)
In TRK FPA mode, when the drift angle or flight path angle is not valid, an FPV flag appears.
5. FD flag (red)
If both FMGCs fail, or if both FDs are disengaged and the FD pushbutton is on and the attitude is valid,
a red FD flag appears.
6. SPD flag (red)
If speed information fails, a SPD flag replaces the speed scale.
7. SPD SEL flag (red)
If selected speed information fails, a SPD SEL flag appears.
8. SPD LIM flag (red)
This flag appears when both FMGCs (flight envelope part) are inoperative, or in case of SFCC dual
flap/slat channel failure.
In this case, the following PFD information is lost : VLS, S, F, Green Dot, Vtrend,
Vmax, VFE next, VSW.
In case only Vmax or VLS is lost, the flag comes up on the PFD but the remaining valid information
still appears.
9. V1 INOP flag (red)
When the V1 signal is not valid, a V1 INOP flag replaces the digital value.
10. ALT flag (red)
If the altitude information fails, the ALT flag replaces the altitude scale.
11. CHECK ALT flag (amber)
The CHECK ALT flag appears, as does an ECAM caution, if the disagree between the two PFDs
altitude indications is greater than 250 feet when QNH is selected, or 500 feet when STD is selected.
The caution and the flag disappear, when the pilot's and the copilot's barometer references disagree.
12. ALT SEL flag (red)
If the selected altitude information fails, an ALT SEL flag appears.
13. V/S flag (red)
If the vertical speed information fails, the V/S flag replaces the vertical speed scale.
14. LOC and G/S flags (red)
If the localizer or glideslope receiver fails, a LOC or G/S flag appears on the deviation scale.
15. V/DEV flag (red)
If the vertical deviation information fails and the LS pushbutton is not pressed, a V/DEV flag replaces
the V/DEV scale.
16. RA flag (red)
If both radio altimeters fail, this flag appears in place of the radio height indication when the aircraft
altitude is below the transition altitude. The ground reference indication (red ribbon) will disappear.
17. DH flag (amber)
A DH flag appears, when the aircraft reaches the selected DH.
18. HDG flag (red)
If the heading information fails, the HDG flag replaces the heading scale.
19. CHECK HDG flag (amber)
The CHECK HDG flag appears, as does an ECAM caution, if there is a discrepancy (5°) between
pilots's and copilot's heading indications.
20. MACH flag (red)
This flag appears, if the Mach data fails.
21. V/DEV (amber)
At the top of the glide scale, this message flashes when in approach phase and, either FINAL mode
is armed/engaged, or a non-LS approach has been selected, and the LS pushbutton is selected.
22. WINDSHEAR (red) or W/S AHEAD (red or amber) warnings
WINDSHEAR : Reactive windshear warning. Displayed, when the FMGC
detects windshear.
Refer to 2.22.40.
W/S AHEAD : Predictive windshear warning. Displayed, when a windshear alert is generated by the predictive windshear system. Refer to 2.34.60.
Note : 1. All flags except SI, V1 INOP, DME 1 (which are steady) flash for 9 seconds then are steady. DH flag flashes for 3 seconds then is steady.2. For TCAS, Refer to 2.34.80.
23. DME 1 flag (red)
When DME distance is not available, a DME 1 (on PFD 1) or DME 2 (on PFD 2) replaces the DME
distance indication.
24. ILS flag (red)
If an ILS frequency is not available, or if either the LOC or G/S signals fail, an ILS flag replaces the
ILS frequency indication.

[philpop]

Tonight, French TV TF1 has broadcasted a testimony from a Air France maintenance manager explaining that the pitot tubes issue was well known at Air France and shown internal documents stating that several critical problems has already occurred on AF CDG-NY as well as AF CDG-TOKYO

[Captain-Crunch]

Boac, yes, well in that case, only these two:

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

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

fell into the definite bin.

These results were passed along via an exchange of emails so I will try a prearranged phone conversation to see what else can be made more solid in the list.

On the "prototype airliner", the A300, Flight Path Vector, is a PFD presentation that can be selected on the glaresheild to predict on the Attitude Display where the mass of the airplane is going to wind up. You "Fly the Bird" target and it helps you manage energy. I know it would likely be a cascading failure from either the AIDRU, airspeed data loss, or the IRU portion itself. Is the A330 the same?

(A330/340 drivers are amazingly silent today...)

[Crossbleed]

Maybe they've had a gutfull, CC. :ok::ugh:

[Captain-Crunch]

Crossbleed said:
Shocking
Maybe they've had a gutfull, CC.

Yeah, maybe you're right CB! :}

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

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

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

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

Also, I noticed, there were big ships hanging out at those coordinates for several days after the accident, ships (http://www.sailwx.info/shiptrack/shiplocations.phtml?lat=6.0&lon=-29.0&radius=300)

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

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

.

[Plastic Bug]

PJ2,

Thank You.

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

Here's the deal for the unknowing:

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

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

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

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

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

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

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

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

Some have suggested that the crew kicked the tail off.

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

What's left?

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

How did that happen?

The NAV ADR DISAGREE message.

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

The A/P and A/T messages?

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

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

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

Is anyone detecting a theme here?

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

PB

[vapilot2004]

Edit: @ Plastic Bug - It appears we have posted simultaneously. And on the same subject as well.

@Grounded101:

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

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

@Captain Crunch:

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

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

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

Thank you for the praise but it is undeserved on my part. It is not my sole analysis. I have assistance and will pass along the kind words. The more we look at the data, the more perplexing it becomes.

[lomapaseo]

It's been more than 24 hours since I posted on this thread so I hope that I'm not overloading it with me-too stuff.

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

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

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

After we have gained some more factual information about what happened maybe then we can talk about knowledge based pilot experience.

[Plastic Bug]

VAPILOT,

No sweat,

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

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

Everything else is eventual.

PB

[Interflug]

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

[robbyxp]

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

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

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

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

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

Hope this helps.

[tarik123]

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

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

Can the GPS data be used to establish which ADR is working correctly,
because GPS ground speed is very accurate and will give a very good
reference to which ADR is working correctly?

[teropa]

Hi,

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

Consider the above for a moment.

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

rgds,
Tero

[Airbubba]

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

Thanks for the insight.

Do you know if AF used Inmarsat, or did they use another provider, e.g. Iridium?

[dollusa]

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

On 447 ...there must have been something wrong and accumulating.
Lets hope we (or the sub) find the boxes.
Joe

[glastonaut]

The Brazilian Navy has some photoes of the recovered tail

https://www.mar.mil.br/menu_h/hot_site_air_bus/index.html

(see under fotos)

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

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

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

This doesn't explain how the tail may have seperated, but should shift some of the focus to the rear structure, which I believe is metal on the A330.

[curious digger]

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

And just a question for somebody who might know. Am I right that adiru is just a signal processor? And the processed data from the sensors are going from adiru to the flight control comps?

[PPRuNe Pop]

Please!!

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

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

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

Thanks.

[eliptic]

The French secret service is investigating whether two passengers on board the doomed Air France 447 flight had links to Islamic terrorism. It raises the possibility that the crash was not an accident.


I really hope they find that box soon,,the speculations starts getting far out of control it feels

[Bearcat]

my tuppence half penny....

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

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

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

[NotPilotAtALL]

Hello,

That's about terrorism ....

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

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

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

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

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

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

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


Google translation:

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

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

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

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

They stressed that no serious claim had been registered.

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


Nevertheless .. this statement is ludicrous ...

They stressed that no serious claim had been registered.

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

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

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

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


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

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

Regards. http://smilies.sofrayt.com/%5E/a/bye.gif

[eliptic]

They stressed that no serious claim had been registered.


that opens for the terrorist to make claims now then, just to make it worse:ugh:

[Expressflight]

Correction to NotPilotAtALL's translation of the final sentence:

"sans que l'équipage n'ait envoyé de deniers messages de catastrophe." means "without the crew having sent any last messages of disaster."

Quite the opposite of the Google translation.

[Celestar]

@philpop

Tonight, French TV TF1 has broadcasted a testimony from a Air France maintenance manager explaining that the pitot tubes issue was well known at Air France and shown internal documents stating that several critical problems has already occurred on AF CDG-NY as well as AF CDG-TOKYO

He’s a simple hangar mechanic. That’s it. Nothing new here as we know AF had started the process of changing them before the crash. Useless “sensational” interview as the guy had probably no clue if his instructions were dictated by a SB or an AD.

[Wytnucls]

I have been wondering for a while now what could have caused the PRIM 1 and the SEC 1 to fail at the same time, at 02:13.
Losing two flight computers is not dramatic in itself as one computer is sufficient to control the aeroplane, although losing two at the same time is quite rare, in my experience.
Flight computers rely on feedback from the control surfaces to make sure the movement order was carried out, otherwise they go off-line and control gets transfered to the next computer in line.
The only control surface where both PRIM 1 and SEC 1 are in control at the same time (apart from spoilers) is the rudder:
SEC 1 at the PFTU (Artificial feel and rudder trim)
PRIM 1 at the rudder itself.
Incidentally, in Alternate Law 2, the BCM (Back Up Control Module) is also active, providing alternate yaw damping, but no turn coordination.
It is perhaps a long shot, but a rudder not responding to electrical orders may have tripped PRIM 1 and SEC 1 at the same time.
Your thoughts on this one?

[wilyflier]

Moderators and web designers
.... There is a problem with trying to relocate past posts, particularly as we are often slagged off by others for not reading from the start
.
...When you delete a post, permalink reference numbers of all the existing subsequent posts changes. Not only that, but if there have been several deletions, more recent posts get put back onto an earlier PAGE number.
....It becomes harder for us to keep a mental picture ,or written list, of earlier posts of relevance.Thus harder to cross refer to something vaguely remembered as having been said before.
....Is it possible for such groups as photos, or technical diagrams ,or maps.or timelines ,to be relisted and rebundled in some way , so that we can see their relationship and contradictions in one place?
.....At the very least can posts be allowed to retain their serial number? ( after all they are shown as PERMAlink)
.....Two off thread points, Moderators have and do a hell of a job on this thread, how do you get the time to keep reading it all?
......Brazillian Authorities seem to have done a good job right beyond the boundaries of their responsibility.
wilyflier

[Ground Brick]

Googled for more info on SATCOM, if it was SATCOM... :)

The Iridium antenna does not need to be aimed. Like a cell phone antenna, its coverage is omnidirectional. It can be fixed on top of the fuselage and mounted with relatively low cost and complexity.
Inmarsat antennas are mechanically steered or electronically steered. The former type requires a steering mechanism, a lot of moving parts, and a radome big enough to cover the whole range of antenna motion.

Inmarsat services, Aero L
The Aero L service operates in the Inmarsat global beams and provides aircraft with real-time, low-speed, two-way data communications capability. Aero L is a packet data service designed primarily for aircraft operators who require a highly reliable data communications capability. Using a packet data link at speeds up to 1.2 kbps, Aero L is International Civil Aviation Organization/Standard and Practices (ICAO/SARPS) compliant and is an essential service for commercial airline customers who require a backup communications system for transmitting cockpit data or for real-time flight monitoring in critical operational environments. Aero L uses a small low-gain antenna.
Global data communications at 600 to 1200bps, principally to support air traffic control and airline operations. Supports Acars/Aircom messaging. ICAO approved for safety services.

Looks that it was Inmarsat, Aero L or better service. At least 600\1200 bps.

I am not 100% excuding HF, just from my expierence it less reliable than SAT, especialy when you have lighting nearby.

Found on wiki about ACARS : 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.

If it was HF - at 2:14z A447 had VS in place.
If it was SATCOM Inmarsat - at 2:14z plane wings were more or less horizontal.
Usualy SATCOM antena positioning device has its own GPS, so hard to tell was IR data available or not. Will try dig more info about SATCOM Inmarsat antenas

[Feline]

@wilyflier:

.... There is a problem with trying to relocate past posts, particularly as we are often slagged off by others for not reading from the start
...When you delete a post, permalink reference numbers of all the existing subsequent posts changes. Not only that, but if there have been several deletions, more recent posts get put back onto an earlier PAGE number.
....It becomes harder for us to keep a mental picture ,or written list, of earlier posts of relevance.Thus harder to cross refer to something vaguely remembered as having been said before.
....Is it possible for such groups as photos, or technical diagrams ,or maps.or timelines ,to be relisted and rebundled in some way , so that we can see their relationship and contradictions in one place?
.....At the very least can posts be allowed to retain their serial number? ( after all they are shown as PERMAlink)

Had the same problem in keeping track myself - so now make a note of the last poster's user name and the time of their post (LH side of post) - then much easier to establish where you left off

FWIW

[lomapaseo]

A couple maps of the debris finds can be found on page 49, post 975 of this thread.

Thanks to Google and SeattlePi.com (Air France Flight 447 update: Body count, maps & reports)...

Brazilian military release of search efforts with maps can be found in pdfs here: https://www.defesa.gov.br/imprensa/m..._MATERIA=33110


I can't read Portugese and I sure can't decipher anything that confirms where the tail vs the door vs the seats and bodies were found. So the speculation continues about the degree of breakup in the air if any.

[Config Full]

F-GNIH is an A340-313X but this is the closest to the information we have about AF447 and the Air Caraibes incidents detailed in the report posted in this thread. This is in French and unfortunately I do not have time now to translate all of it, but if you need any assistance I'll be glad to help later on.

After losing all 3 pitots failure, the aicraft got the same warnings as in the above. The crew sent a MAYDAY message. Finally the crew was able to recover and opted for the pursuit of the flight to Tananarive.

F-GNIH AF908 CDG - TNR -
ALARME STALL ET PERTE DES INDICATIONS DE VITESSE SUR LES PFD
CDB PF en place gauche et OPL L. xxxx PNF en place droite
OPL R. xxxx de repos

Au FL 370 avec une SAT à -51°C et un vent du 080 pour 18 Kts environ sur l'AWY UB612 avec un OFF SET 1R, entre les points OBD et MLK en contact radio avec KHARTOUM, comme nous étions en limite de couche nuageuse avec quelques turbulences légères, j'avais attaché les PAX.

Nous étions au crépuscule avec une faible luminosité.
Puis nous sommes entrés dans la couche, et peu après nous avons commencé par avoir une odeur de brûlé légère qui a duré une vingtaine de secondes et qui ne semblait pas être d'origine volcanique (pas d'odeur d'oeufs pourris) mais plutôt d'odeur électrique pour moi et d'odeur conditionnement d'air pour l'OPL. Puis cette odeur a disparu. Cette odeur a été confirmée en cabine par les PAX et les PNC entre les rangs 3 et 14 par la suite.

Nous avions le radar météo en marche sur calibré sans échos apparents toujours dans la couche et environ minute après cette odeur de brûlé, nous avons eu des turbulences fortes. J'ai donc fais le message « Ici le poste de pilotage PNC assis attachés turbulences fortes ». J'ai réduit la vitesse à
Mach 0,80 (un tout peu au-dessus de green dot)
Quelques secondes après l'indication de vitesse sur le PFD OPL passe brusquement de 280 Kts à 100 Kts dans le bandeau rouge et cela à duré de nombreuses secondes. En même temps sur le PFD CDB variation très forte de vitesse avec vitesse indiquée green dot moins 15Kts et un speed trend à
moins 50 Kts.
Au même moment (il était 15h10 TU) Alarme rouge A/P OFF puis dans la foulée alarme ambre ADR DISAGREE, IAS DISCREPANCY, ALTN LAW PROT LOST, REAC W/S DET FAULT.
Suivi à 15h11 de l'alarme ambre RUD TRV LIM FAULT.
Suivi immédiatement de l'alarme STALL STALL STALL (sans l'alarme cricket associée) avec indication de TOGA LK. Comme j'avais toujours le speed trend à moins 50 Kts, j'ai piloté l'avion en manuel avec mise en descente et léger virage à droite pour sortir de l'AWY. L'avion répondant très mollement avec sur le PFD CDB plusieurs régressions de vitesse dans le bandeau rouge inférieur. En même temps j'ai demandé à l'OPL d'envoyer un message MAYDAY. Pendant la descente bruit d'impact (grêle ???) entendu au cockpit.
Descente jusqu'au FL 340. La vitesse avion étant redevenue correcte j'ai débraillé l'ATHR pour sortir du TOGA LK. Les indication de vitesse étant similaires coté CDB et OPL, mais avec en bas des 2 PFD sur l'échelle des vitesses l'indication SPD LIM rouge qui est restée jusqu'à la fin du vol.
Stabilisation de l'avion, puis application de la procédure IAS DOUTEUSE, et en même temps mise en marche des anti givrages ENG et WING ainsi que passage des PACKS FLOW sur HIGH (dans le doute d'un nuage de poussière ou de fumée pour éviter le pompage GTR comme dans la procédure
nuage volcanique). Comme les indications de vitesse et d'altitude étaient correctes (avec cross check avec les indications de Ground speed et d'altitude GPS, ainsi quand comparant les données de vent de l'OCTAVE), ré engagement de l'AP1 et de l'ATHR.
À aucun moment nous n'avons eu d'alarme ICE DETECTION.
J'ai réveillé le second OPL qui était en repos, puis nous avons traité les check-list ECAM.
Descente au FL 330 puis cancel du MAYDAY et poursuite du vol à ce niveau.
L'avion étant passé en ALT LAW (MAX IAS 330Kts/M.82) j'ai préféré avoir une plage de domaine de vol élargie et continué le vol à Mach 0,80.
Au niveau du bilan : avion en ALT LAW confirmé par le status et les croix ambres sur les PFD, REAC W/S DET FAULT, ALT LAW PROT LOST, ADR DISAGREE et F/CTL RUD TRV LIM FAULT (2
NOGO).
FOR LDG USE FLAP 3.
Il est important de noter que l'indication sur la page circuit de l'écran SD ,du RUDDER TRAVEL LIMITER était ambre mais à mi-course entre le neutre et le plein débattement gouverne de direction.
Contact avec le CCP pour savoir quel était l'état de la cabine et des PAX. Seule la turbulence forte a été ressentie par les PAX.
J'ai appelé par SAT COM la maintenance pour faire une recherche plus poussée des problèmes et suites à leurs recommandations nous avons reseté tous les calculateurs de commandes vol PRIM et
SEC sans aucun résultat. (à ce moment là nous avions le carburant pour un retour vers NCE ou FCO).
Sur la check-list développée de F/CTL ALTN LAW (PROT LOST) on peut lire pour APPR PROC FOR LDG USE FLAP 3. (Il n'y a pas d'indication dans le QRH sur le tableau de correction après panne)
Par contre dans la développée du F/CTL RUD TRV LIM FAULT en APPR PROC FOR LDG USE FLAP 2, ce qui est confirmé par le QRH dans le tableau de correction après panne.
Comme il est apparu cette anomalie entre le QRH qui demande de se poser volets 2 et le status qui nous demande de se poser volets 3 il était donc nécessaire de nouvelles recherches et donc la décision d'un appel plus tard à QB.
Nouvel appel SAT COM à QB qui n'a pas trouvé d'explication supplémentaire sur la différence de braquage volet, puis au CCO pour voir avec eux pour la suite du vol et le dépannage de l'avion, le retour vers l'Europe n'étant plus possible avec le carburant restant, il se posait alors la décision de
continuer sur TNR ou de dérouter sur RUN. Décision de continuer sur TNR avec demande de ma part de surseoir au réveil des collègues qui devaient ramener l'avion sur CDG compte tenu des 05h00 minimum de recherche de panne à TNR.
Nous avons continué le vol avec le Pitot heat sur on et le calibrage radar sur MAX.
Il est à noter que pendant toute la descente en ALT LAW, l'avion ne répondait pas à ma demande de régression de vitesse par l'intermédiaire de la commande SPD du FCU (nous étions en OPEN DES), et j'ai donc du débrayer l'AP pour faire régresser la vitesse. Le pilotage de l'avion m'a donné l'impression d'un avion très mou aux commandes, qui ne correspondait pas au ressenti du pilotage pendant le décollage et la montée. Du fait de la différence entre le QRH et le status, j'ai donc suivi le
status et nous nous sommes posés volets 3.
En regardant en ACMS nous avons vu les indications de Pitot 1 & 2, 2 & 3 et 1 & 3 fault à 15h10TU En post flight report
15h07 BMC 3
15h10 AUTO FLIGHT AP OFF
REAC W/S DET FAULT
IAS DISCREPANCY
NAV ADR DISAGREE
15H11 F/CTL RUD TRV LIM FAULT
J'ai fais le tour de l'avion avec un des OPL et aussi bien le radôme que les pitots semblaient intacts.
Seule la sonde d'incidence coté OPL était fortement inclinée presque verticale. Il n'y avait pas de trace d'impact ni de rayure sur la peinture du radôme, ni sur les pare-brises.
J'ai fait, après avoir réuni tout l'équipage (PNT et PNC) un débriefing pour expliquer ce que nous avions vécu et rassurer tout le monde et répondre aux questions.
Pour les questions de la DM
Vol au FL 370 pas de cisaillement de vent ressenti (vent du 080/18Kts) le vent était stable depuis plus d'une demi heure en force et direction.
Vol à mach 0,80 car légère turbulence (PAX attachés)
Pas de présence audible de grêle au début des incidents (mais nous avons entendu pendant la descente des bruits d'impacts au cockpit (grêle ???).
Température SAT -51°C (nous n'avons jamais eu d'alarme ICE DETECTION)
Pas de phénomène orageux (rien au radar météo qui était sur calibré et pas d'éclair d'orage visible).
Début de la turbulence forte vers 15h09 suivie des alarmes citées ci-dessus à 15h10 et 15h11 TU
L'indication de vitesse côté OPL est passé de 280 Kts à 100 Kts dans le bandeau rouge et est restée de nombreuses secondes comme cela.
Coté CDB la vitesse indiquée est passée de green dot - 15 Kts avec un speed trend à -50 Kts.
Alarme STALL (sans l'alarme cricket) plusieurs séries avec plusieurs incursions de speed indiquée dans le bandeau rouge inférieur.
Stabilisation avion au FL340 puis poursuite du vol au FL 330.
Durée estimé des incidents 3 à 5 minutes.

[Rananim]

AIR CARAIBE TIMELINE
22:22:20 to 22:22:36 TAT increases from -14 to -5
22:22:36 to 22:23:00 TAT constant at -5
22:22:59 CAS reduces from 273 to 85 kt (AP disengage FD flags)
22:23:36 to 22:23:45 STALL warnings
22:23:00 to 22:23:54 TAT decreases to -14
22:24:25 CAS recovers to 275kt
22:24:24 to 22:24:40 FD's re-engaged
22:24:41 AP re-engaged

Elapsed time 2 mins 21 secs.
Flight time with unreliable speed 1 min 26 secs
Working assumption:degree of turbulence far less severe to AF447

Does anybody technically-minded have anything to say re post #1148 from Interflug.Confirmation of:
-ACARS message advisory not warning(already established)
-Rudder travel limit gelee(frozen) at ten degrees after ADR disagree?Correct?
-SEC controls this "lock-out" function?
-Not theoretically possible for rudder travel limit to default to higher travel limit than TEN?
-Full travel available after slats out?What keeps slats in?Airloads only?

Is there theoretically the possibility, that the RTL got a wrong - much lower - CAS/TAS before it froze?
(Interflug)

It is perhaps a long shot, but a rudder not responding to electrical orders may have tripped PRIM 1 and SEC 1 at the same time.
(Wytnucls)

Anything at all that could have let the crew get more rudder deflection than they bargained for ??

[Will Fraser]

As the VS/Rudder assembly is recovered and photography is available, it seems reasonable to analyze it as it appears.

In one image, I continue to believe the most forward mounting has remained in place, at least in part. It appears to be folded under the port side of the VS root at the front, just aft the dorsal fin attachment.

If so, and concluding an airborne (airflow induced) failure to port, the a/c was at the time yawed left. If so, it is reasonable to also consider a slight roll left, due to asym lift and differential sweep relative to airflow.

If true, that the a/c yawed left enough to fail the Vertical components, the roll will also introduce an exaggerated AoA HS relative to the airflow, which may have failed the HS/E on the starboard side. If the VS/R and HS/E (starboard) failed together, the damage to the base of the Rudder and the extreme damage to the aft mate (VS) would follow.

If the Rudder was perceived to be unresponsive (to the PRIM parameters) at this point, it might explain the Rudder message in ACARS. It might also explain the sequence of other data, including PRES. The possible failure of fuselage structure with HS loss certainly involves the aft pressure bulkhead.

Now the a/p disc. Involuntary, and purportedly due to unmitigable (a/p) control limits, the turbulence associated with its disengage is so far unknown. Grabbing hold of the now hand flown controls may have been quite a challenge (sic). With the disintegrating data on the glass and utter lack of cues..... At this point, we're back to a/p versus hand flying in severe(extreme) turbulence.

The question might be asked, Would it not be more advisable to be mentally flying the a/c along with the a/p up to a manual disconnect?

If surprisingly left with a/p unable to perform, versus hand flying well in advance of such time, what is the proper course?

[DC-ATE]

There's an awful lot of text written on the rudder. While it's obvious it parted the aircraft at some time, I find it hard to believe it was pilot induced. I'd like to hear from those (transport pilots only, please) that actually use the rudder that much in flight OTHER than during take-off and approach/landing.

Edit:
P.S. Maybe I should clarify that by asking Airbus pilots, or more specifically, AF447 type. Although other types/mfgrs would be of interest as well.

[Will Fraser]

DC ATE

Direct me to the post that claims pilot ruddering caused anything?

The Rudder didn't leave the a/c, the VS left. It was a twin, the engines have alot to answer for.

[RealQuax]

Will,

there is a definitve answer: Let the a/p fly until it proves its unability. The reason is: hand-flying in such high-workload-situations definitely segregates the 2 pilots: One is occupied flying, whereas the other has to handle all the system failures. So, very little redundancy for the trouble-shooting, if at all.

I had a chat with a friend flying the 747 (I have no recent Boeing Experience, I have to confess). What he says, that the similar procedure in the -47 keeps the a/p flying until disconnected by the crew. Any informed comment?

[BOAC]

I'm having trouble keeping up with the 4 threads running on this.:ugh: Has ANYONE any latest RELIABLE info on the debris and body recovery? The latest I have seen is 7/6.

EDIT: Make that 9/6

[DC-ATE]

Will Fraser -
Direct me to the post that claims pilot ruddering caused anything?Direct me to the post that claims pilot ruddering caused anything

With over a thousand posts here and other threads on this, that would be impossible ! I simply recall mention of 'possible' over-controlling in OTHER than Normal Law.

Edit: Follow-up to your addition.

You are correct...the 'rudder' didn't leave the a/c, the whole tail did. But, as in AA587, it was claimed that the seperation was caused by the pilot overloading the rudder.

[Will Fraser]

RealQuax

That's the point, 'until disconnected by the crew'. Why not a proactive D/C ? "What's it doing now?" (sic).

DC ATE- Noted, but the Rudder is at this point what is being discussed.
You are inferring I think some blame here, that's unacceptable, imo. The whole tail did NOT leave the a/c, the VS is not the tail, it is a component of the "tail".

[Will Fraser]

DCATE

Did you read the rest of my post? Engines? The boxes are crucial.

[WhyIsThereAir]

> You are correct...the 'rudder' didn't leave the a/c, the whole tail did. But, as in AA587, it was claimed that the seperation was caused by the pilot overloading the rudder.

I have been following this thread closely since page 6, and have a pretty good memory. You are correct. In the beginning there was a great deal of claiming by the completely uninformed that the PF overcontrolled the rudder and broke it off.

Then the pictures of the VS showed up, with enough detail to show that it still had the rudder attached and yanked the roots out of the aft body section, rather than failing the attach lugs on the VS itself. Since that point most of the claims of pilot overcontrol have evaporated.

In any case, we do not, and at this point with the available information CAN NOT *KNOW*, whether the PF overcontrolled, whether some mechanical/software failure automatically overcontrolled, or whether no overcontrol occurred at all. All we KNOW is the plane fell out of the sky, and at some unknown point the VS fell off. We do not know WHY it fell off, we do not know which direction it fell off, and there isn't enough info available for the slightest productive speculation.

[DC-ATE]

Will Fraser -

Yes, I read the rest about the BIG motors [my add] and their possible affect. Just haven't seen any 'speculation' in that area.....yet.

[augustusjeremy]

Rudder Travel Lim. Fault in the Acars Messages and its link to rudder/fin/whatever loss would stand valid only if someone proved that the SatCom link would keep functional after the separation.

Either it must be plausible that the a/c wings could keep minimally horizontal and also minimally stable in that position with a missing rudder/fin/whatever or it must be proven that the satcom (electronically steered / phased array ?) link would stand even to abrupt changes in the a/c roll, pitch angle.

[Safety Concerns]

come on lets back on the centre line. It might make a good bedtime story talking about losing VS etc. but its unfortunately bull****.

The loss of a VS would produce many more faults than you have here, many more.

Once again acars is only a messaging system. It doesn't produce any messages it just sends them. The messages are aircraft system time stamped and not acars time stamped.

What we clearly see with these messages is the beginning of a sequence of tragic events tied to air data but still for reasons unknown.

[The Chaser]

Config Full Re: AF908 CDG-TNR, captain PF report

I have made a very rough translation of the report using http://www.systran.co.uk/ (http://www.systran.co.uk/)

I have only a very basic knowledge of the language (apologies in advance) and its intended intonations and nuances, so have kept the grammar amendments to a minimum to avoid the possibility of unintentionally mistranslating the proper intent of comments contained with the report. You might have to knock any mis-trans or rough edges off.

F-GNIH AF908 CDG - TNR -

STALL ALARMS AND LOSS OF THE SPEED INDICATIONS ON THE PFD

CDB PF in left seat and OPL L. xxxx PNF in right seat, OPL R. xxxx in rest

To FL 370 with a SAT with -51°C and a wind of the 080 per approximately 18Kts on AWY UB612 with OFFSET 1R, between points OBD and MLK in radio operator contact with KHARTOUM, as we were in limit of vapor cloud with some light turbulences, I had attaché the PAX.

We were in the twilight with a weak luminosity.

Then we entered the layer, and shortly after we started by having a light smell of burning which lasted about twenty seconds and which did not seem to be of volcanic origin (not rotted egg odor) but rather of electric odor for me and of odor air conditioning for the OPL. Then this odor disappeared. This odor was confirmed in cabin by the PAX and the PNC between the rows 3 and 14 thereafter.


We had the radar weather walks from there on gauged without apparent echoes always in the layer and approximately minute after this smell of burning, we had strong turbulences. I thus have make the message Here “attached cockpit PNC sitted strong turbulences”. I reduced speed to
Mach 0.80 (a little above green dot)

A few seconds after the indication speed on PFD OPL abruptly from 280 Kts passes to 100 Kts in the red stringcourse and that to lasted of many seconds. At the same time on PFD CDB very strong variation speed with speed indicated green dot less 15Kts and a speed trend to less 50 Kts.

At the same time (it was 15h10 TU) Alarm red A/P OFF then in the alarms amber ADR DISAGREE, IAS DISCREPANCY, ALTN LAW PROT LOST, REAC W/S DET FAULT.


Followed at 15h11 of alarm RUD TRV LIM FAULT with amber.


Follow-up immediately of alarm STALL STALL STALL (without associated alarm cricket) with indication of TOGA LK. As I always had the speed trend to less 50 Kts, I flew the plane manually with setting in descent and light turn to leave the AWY on the right. The plane answering very listlessly with on PFD CDB several regressions speed in the lower red stringcourse. At the same time I asked the OPL to send a message MAYDAY. During the descent rustles of impact (hail???) heard with the cockpit.


Descent until FL 340. Correct speed plane being become again I have slovenly the ATHR to leave TOGA LK. The indication speed being similar with dimensions CDB and OPL, but with bottom of the 2 PFD on the scale speeds the red indication SPD LIM which remained until the end of the vol.
Stabilization of the plane, then application of the IAS procedure DOUBTFUL, and started at the same time of anti icing ENG and WING like passage of PACKS FLOW on HIGH (in the doubt of a cloud of dust or smoke to avoid pumping GTR as in the procedure volcanic cloud). As the indications speed and altitude were correct (with cross-check with the indications of Ground speed and GPS altitude, thus when comparing the data of wind of the OCTAVE), ré engagement of the AP1 and the ATHR.


We did not have at any time of ICE DETECTION alarm.


I awoke the second OPL which was in rest, then we treated checklist ECAM.

Descent in FL 330 then chancel of the MAYDAY and continuation of the flight on this level.


The plane having passed in ALT LAW (MAX IAS 330Kts/M.82) I preferred to have a beach of flight envelope widened and continued the flight at Mach 0.80.


On the level of the assessment: plane in ALT LAW confirmed by the status and the crosses ambers on the PFD, REAC W/S DET FAULT, ALT LAW PROT LOST, ADR DISAGREE and F/CTL RUD TRV LIM FAULT (2
NOGO).
FOR LDG USES FLAP 3.


It is important to note that the indication on the circuit page of screen SD, of the RUDDER TRAVEL TO LIMIT was amber but with mid--chases between the neutral and full clearance rudder.


Contact with the CPC to know which was the state of the cabin and the PAX. Only strong turbulence was felt by the PAX.


I called by SAT COM maintenance to make a more thorough research of the problems and continuations to their recommendations we reseté all the calculators of orders flight PRIM and SEC without any result. (at this time there we had the fuel for a return towards NCE or FCO).


On the developed checklist of F/CTL ALTN LAW (PROT LOST) one can read for APPR PROC FOR LDG USES FLAP 3. (There is no indication in the QRH on the table of correction after breakdown)


On the other hand in developed F/CTL RUD TRV LIM FAULT in APPR PROC FOR LDG USES FLAP 2, which is confirmed by the QRH in the table of correction after breakdown.


As it appeared this anomaly between the QRH which requires to be poser volets 2 and the status which requires of us to be poser volets 3 it was thus necessary new searchs and thus the decision for a call later to QB.


New call SAT COM to QB which did not find an explanation additional on the difference in steering shutter, then with the CCO to see with them for the continuation of the flight and the breakdown service of the plane, the return towards Europe not being more possible with the remaining fuel, it was posed the decision then of to continue on TNR or to divert on RUN. Decision to continue on TNR with request for my share to postpone the alarm clock of the colleagues who were to bring back the plane on minimum CDG taking into account the 05hr00 of fault finding to TNR.


We continued the flight with Pitot heat in ON position and calibration radar on MAX.


It should be noted that during all the descent in ALT LAW, the plane did not answer my request for regression speed via order SPD of the FCU (we were into OPEN DES), and I have thus to disconnect the AP to make regress speed. The piloting of the plane gave the impression of a very soft plane to me to the orders, which did not correspond to not felt piloting during takeoff and the rise. Because of difference between the QRH and the status, I thus followed it status and we were posés volets 3.


While looking in ACMS we saw the indications of Pitot 1 & 2.2 & 3 and 1 & 3 fault at 15h10TU In post flight report
15h07 BMC 3
15h10 AUTO FLIGHT AP OFF
REAC W/S DET FAULT
IAS DISCREPANCY
NAV ADR DISAGREE
15h11 F/CTL RUD TRV LIM FAULT


I have make the turn of the plane with one of the OPL and as well the radome as the pitots seemed intact.


Only the angle of attack sensor with dimensions OPL was strongly tilted almost vertical. There was no trace of impact neither of stripe on the painting of the radome, nor on avoid-break.


I made, after having joined together all crew (PNT and PNC) a débriefing to explain what we had lived and to reassure everyone and answer the questions.


For the questions of the DM


Flight in FL 370 pas de shearing of wind felt (wind of the 080/18Kts) the wind was stable since more than one half hour in force and direction.


Flight at Mach 0.80 because light turbulence (attached PAX)


No audible presence of hail at the beginning of the incidents (but we heard during the descent of the noises of impacts to the cockpit (hail???).


Temperature SAT -51°C (we never had ICE DETECTION alarm)


No stormy phenomenon (nothing with the radar weather which on was gauged and no visible flash of storm).


Beginning of strong turbulence around 15h09 followed by alarms quoted above at 15h10 and 15h11TU


The indication speed side OPL passed from 280 Kts to 100 Kts in the red stringcourse and remained many seconds like that.


Coté CDB speed indicated passed from green dot - 15 Kts with a speed trend to -50 Kts.


Alarms STALL (without alarm cricket) several series with several incursions of speed indicated into the lower red stringcourse.


Stabilization plane with the FL340 then continuation of the flight in FL 330.

Duration estimated of incidents 3 to 5 minutes.

[falconer1]

one thing is for sure now..

the different reports, like Air Caraibe, and AF 908 and the speculation about a similar problem with the accident in question will lead to careful evaluation and new training scenarios in the SIMs..

question to the A330 / 340 drivers..

do the simulators employed presently faithfully duplicate handling at high alt in alt law?

[alph2z]

Have non-Airbuses ever had this pitot major icing problem ?

Or is it that Airbuses flight computers are much more sensitive to deviating pitot sensors due to icing ?

How is the B777 different and less sensitive to pitot icing and its flight computers are less sensitive to pitot icing ?
.

[Carnage Matey!]

Different pitot tube design. There's no indication the Airbus computers are any more sensitive to bad air data than the Boeing ones. One rule holds true for all computers: garbage in = garbage out.

[testpanel]

I have read a lot about the possibillity that icing (or anything else) MAY have clogged the pitot-tubes, airlines changing the tubes etc etc.

But to measure airspeed (at altitude) you need static-pressure as well!
I have not seen any discussion on this, or does it work different on the -330? (i can´t imagine)

[DorianB]

No 25 - AIR FRANCE FLIGHT 447 SEARCH REPORT
PRESS RELEASE 25 (10/06/09, 19h00)
INFORMATION ON THE SEARCH FOR AIR FRANCE FLIGHT 447


The Brazilian Navy Command and Aeronautical Command inform that the Dock Landing Ship Rio de Janeiro , with a crew of 363 military personnel from the Brazilian Navy, should be joining the search and rescue operations from the 19th of June onwards. Having come from Haiti, the ship will pass near the city of Fortaleza (CE), where it will receive the reinforcement of two helicopters, a H-12 Esquilo and a H-14 Super Puma , both of the Brazilian Navy.

The French ship Mistral and the submarine Émeraude have already arrived at the search area and the seagoing tub Fairmount Expedition , contracted by the French government, has received permission to dock, today, at the port in Natal (RN), where it will receive American equipments (sensors and sonars), that will be used to search for the data recorder of the Flight AF 447 and the voice recorder of the cabin (commonly referred to as the "black boxes").

It should be emphasized that these vessels and equipments are at the service of the aeronautical authorities of France, by means of their aviation accident investigation body, the Bureau D’enquêtes et D’Analises pour la Securité de l’Aviation civile (BEA).

The work of these ships will be coordinated by SALVAERO and by SALVAMAR NE, that will monitor the position of these craft so that they do not interfere with the priority task, the search and rescue of bodies. It should be noted that, even though they are in missions of distinct nature, that these ships arriving today will contribute, whenever possible, with the rescue of bodies.

Besides these, two BEA investigators, one a structural engineer from Air Bus and the other a structural engineer from Air France , should be arriving in Recife (PE), on the 14th of June.

The Frigate Constituição , of the Brazilian Navy, is scheduled to arrive tomorrow, 11th of June, to the area where the search effort is concentrated. On the same date, the Frigate Bosísio should be arriving at a location close to Fernando de Noronha, where the 25 bodies on board will be collected by two FAB helicopters, a H-60 Blackhawk and a H-34 Super Puma , currently positioned in Fernando de Noronha.

Due to the meteorological conditions today, some of the search aircraft had their routes altered to areas with more favorable conditions for visual search. Sea conditions were satisfactory for the ships.

NAVAL SOCIAL COMMUNICATION CENTER
AERONAUTICAL SOCIAL COMMUNICATION CENTER

[BOAC]

Thanks to 'The Chaser' for the attempted translation of that report. Interseting to note the use of « Ici le poste de pilotage PNC assis attachés turbulences fortes » in the PA made. I still await someone from AF to confirm whether this is a 'known' description and to what grade it relates.It all sounds very similar, except unfortunately there is no-one to tell the tale.

[JD-EE]

The Chaser - here is what translate.google.com gives. It's slightly more readable.

===8<---
F-GNIH AF908 CDG - TNR --
STALL ALARM INFORMATION AND LOSS OF SPEED ON THE PFD
CBD PF in the left seat and OPL L. xxxx SOPs in place right
OPL R. xxxx rest

At FL 370 with a SAT to -51 ° C and a wind from 080 to about 18 Kts on AWY UB612 with OFF SET 1R, between the OBD and MLK in radio contact with Khartoum, as we were at the edge of layer cloudy with some light turbulence, I tied PAX.

We were at dusk with low brightness.
Then we entered the layer, and soon after we started having a slight burning smell that lasted about twenty seconds and that did not appear to be of volcanic origin (no smell of rotten eggs), but rather electrical smell to me and smell the air conditioning for the OPL. Then the smell has disappeared. The odor was confirmed by the PAX booth and PNC between rows 3 and 14 thereafter.

We had the weather radar in motion on calibrated without echoes still apparent in the layer and some minutes after the burning smell, we had severe turbulence. So I do the message "Here the cockpit sitting PNC Attached turbulence. I reduced the speed at
Mach 0.80 (a little above green dot)
A few seconds after the indication of speed on the PFD passes abruptly OPL 280 Kts to 100 Kts in the red band and it lasted for many seconds. At the same time on the PFD variation CBD high speed with speed 15Kts green dot less speed and a trend to
50 Kts.
At the same time (it was 15:10 GMT) Red Alarm A / P OFF and then in the wake alarm amber ADR Disagree, IAS DISCREPANCY, ALTN LAW LOST PROT, W REAC / S FAULT DET.
15h11 monitoring of the alarm RUD TRV LIM amber FAULT.
Followed immediately by the alarm STALL STALL STALL (without the associated alarm cricket) with TOGA LK. As I always speed trend within 50 Kts, I steered the plane manually, with a call for light downhill and turn right to exit the AWY. The aircraft responding very weakly with the CBD several regressions PFD speed in the lower red stripe. At the same time I asked the OPL to send a MAYDAY. During the descent noise impact (hail?) Heard in the cockpit.
Descent to FL 340. Speed aircraft is returned to correct the sloppy I ATHR to exit the TOGA LK. The rate is similar side CBD and OPL, but down 2 on the PFD speed scale indication SPD LIM red remained until the end of the flight.
Stabilization of the plane, then applying the procedure DOUBTFUL IAS, while activation of anti icing and WING ENG as well as passing on HIGH FLOW PACKS (probably in a cloud of dust or smoke to prevent pumping as in the GTR procedure
volcanic cloud). As indications of speed and altitude were correct (with cross check with the indications of Ground speed and altitude GPS, so when comparing wind data from the OCTAVE), re-engagement of the AP1 and the ATHR.
At no time have we had ice detection alarm.
I woke up the second OPL was at rest, then we addressed the ECAM checklist.
Descent to FL 330 and then cancel the MAYDAY and continued flight at this level.
The aircraft fell in ALT LAW (MAX IAS 330Kts/M.82) I have a favorite beach area expanded flight and continued the flight at Mach 0.80.
At the balance sheet: ALT LAW aircraft confirmed by the status and amber cross on PFD, REAC W / FAULT DET S, ALT LAW PROT LOST, DISAGREEMENT ADR and F / CTL FAULT RUD TRV LIM (2
NOGO).
FOR USE LDG FLAP 3.
It is important to note that the indication on the circuit of the screen SD of RUDDER TRAVEL LIMITER was amber, but halfway between neutral and full deflection rudder.
Contact with the CCP for what was the state of the cabin and PAX. Only the strong turbulence was felt by PAX.
I called SAT COM maintenance to further research the issues and follow their recommendations we reset all the computers and commands flight PRIM
SEC without any result. (at that time we had the fuel for a return to NCE or FCO).
On the checklist developed for F / CTL ALTN LAW (PROT LOST) could be read to APPR PROC FOR USE LDG FLAP 3. (There is no indication in the QRH on the table of correction after failure)
For the developed against the F / CTL RUD TRV LIM in APPR PROC FAULT FOR USE LDG FLAP 2, which is confirmed by the QRH in the table of correction fail.
As it appeared that discrepancies between the QRH requesting arise part 2 and the status which requires us to ask strands 3 and it was therefore necessary to further research and therefore the decision of a later call to QB.
New call SAT COM QB who has not found any additional explanation on the difference in steering component, then the CCO to see them for the theft and troubleshooting of the aircraft, the return to Europe n 'as much as possible with the remaining fuel, the problem then the decision
TNR continue or divert to RUN. Decision to continue on TNR with a request for me to postpone the revival of colleagues who had to return the aircraft in view of CDG 05h00 minimum fault-finding to TNR.
We continued the flight with the pitot heat on and on radar calibration MAX.
It should be noted that throughout the down ALT LAW, the aircraft was not responding to my request regression speed via the control of the FCU SPD (we were in the Open), and I therefore disengage the AP for reducing speed. Piloting the plane gave me the impression of an airplane flying very soft, which was not the feeling of flying during takeoff and climb. Because of the difference between the QRH and status, so I followed the
status and we laid 3 strands.
Looking ACMS we saw indications of Pitot 1 & 2, 2 and 3 & 1 & 3 at fault in 15h10TU post flight report
15:07 BMC 3
15.10 AUTO OFF FLIGHT AP
REAC W / FAULT DET S
IAS DISCREPANCY
NAV ADR DISAGREEMENT
15h11 F / CTL RUD TRV LIM FAULT
I did a tour of the aircraft with one of the OPL and both the radome pitot that appeared intact.
Only the side impact sensor OPL was heavily tilted nearly vertical. There was no evidence of impact or scratches on the paint of the radome and on the windshields.
I did, after meeting all the crew (TFN / PNC) a debriefing to explain what we had lived and reassure everyone and answer questions.
In matters of the DM
Flight to FL 370 not experienced wind shear (wind 080/18Kts) wind was stable for more than a half hour in strength and direction.
Flight at mach 0.80 as slight turbulence (PAX Attached)
No audible presence of hail in the early incidents (but we have heard during the descent of noise impacts to the cockpit (hail ???).
SAT Temperature -51 ° C (we never had alarm ICE DETECTION)
No phenomenon storm (nothing in the weather radar was not calibrated and a flash of lightning visible).
Top of strong turbulence to 15h09 followed alarms above and 15h11 to 15h10 GMT
The rate rose later OPL 280 Kts to 100 Kts in the red band and remained in as many seconds.
CBD side the speed is increased from green dot - 15 Kts with a speed trend to -50 Kts.
STALL alarm (no alarm cricket) series with several incursions of speed shown in the lower red stripe.
Stabilization aircraft at FL340 and continued flight to FL 330.
Duration estimated 3 to 5 minutes.
===8<---

{^_^}

[Safety Concerns]

You are correct Safety Concerns. ACARS is a 'messaging system' only. And yet you restrict your comment to data it provides. You can't have it both ways. You say essentially that ACARS is quite fallible, then you infer that because it doesn't report more, conjecture isn't based in 'evidence', which is it, then? Is it dependable? Does it preclude entertaining things it doesn't 'report', Or is it not telling us the whole (or even major) story because it is only a 'messaging system'?


What I am saying to be clear is that acars is just a relayer of information. The information will go out as and when available or as customer programmed. What it wont do is behave in an extremely selective manner to assist speculative theories just because the VS has been found.

It is simple really no magic. Had the VS caused this accident there would be 1001 more messages. Those messages arent there. All systems send their messages to a central point which then transmits them.

ACARS has nothing to do with anything except that it has assisted this investigation by doing its job and transmitting messages it had absolutely nothing to do with as far as collecting them or producing them is concerned.

[PJ2]

Will Fraser;

Re ACARS messages, indeed it is merely a messaging system and not a flight data analysis tool. We cannot imbue it with more even if it is all we have.

Much of this thread is taken up with "interpreting" ACARS and the tiny traces available; this is very unstable ground upon which to base any thinking whatsoever.

Most have accepted that the trace of the messages "IS" what happened. We do not know this.

Many, including myself, cautioned against such interpretation at the very start of this thread but those who don't know seem to have the least fear in treading in these deep and extremely complex waters. Your post expresses this quite well.

The reason for such caution is, among other reasons, the fact that the ACARS is a maintenance reporting and messaging system, not a flight data analysis tool. The granularity of the data is very high, (stating the obvious).

Also, the ACARS messages that many of spent hundreds of hours pouring over, is only a map of the incoming messages from the fault-reporting sections of the individual systems.

Each AF system component may possibly have it's own BIT (built in test) capability and, when such system is not functioning as designed, the BIT processes analyze, possibly attempt a fix and finally report the fault or failure through the AIMS, (Aircraft Information Management System). I say 'possibly have it's own BIT because the FIDS - Fault Isolation and Detection System also does this job and is installed on FMGC#1, but the AOM does not specify which internal and external failures it monitors/records).

All ACARS functions are heavily tailored to an individual airline's specifications, not Airbus's. We do not have a lot of information on AF's ACARS system design...

The inevitable conclusion and the reason why the sequence of ACARS messages may mislead in the kind of activities taking place here and elsewhere is, the ACARS sequence is a map of the incoming messages and NOT a map of the fault-failure sequence of individual systems, which, due to their internal designs and BIT processes, may not report faults/failures immediately.

The reasons for skepticism are significant. The foundation upon which any theories are posited, is at best, unstable. Hindsight bias is very active especially in the area of pitot and TAT discussions. I posted information a while back not to confirm theories but to make the complexity and uncertainty of the task ahead abundantly clear especially to those who have no experience or training in these areas. This is an extremely (and I mean extremely) complex aircraft which cannot be known deeply by any one individual, and we have mere traces instead of data and tiny slices of the much larger picture in the now-found wreckage of the vertical stabilizer.

One bare thread doesn't make the finished suit. We have small bits of bare threads dancing about and no possibility of summarizing - there is essentially nothing to summarize yet.

We simply do not know the reasons for system faults and structural failures. Further, we cannot even posit theories - such territory is "where angels fear."

We do not know, for example, if the reconfiguration to Alternate Law (1 or 2?) was because of a bank angle exceeding 45deg or because of the loss of ADIRU information, or....?

It is not the positing of theories which in and of itself is unproductive and possibly even harmful. It is the "independant life" such theories swiftly gain in a pressurized pyschological environment predisposed to "finding out" which can distract and blind otherwise knowledgable and intelligent perceptions or cues.

[regularpassenger]

Can I just confirm that the ONLY supporting evidence leading posters to discuss a VS mid air break up is the fact the French Navy found it in the water?

If this is so, surely this is speculation going way to far!

[The Chaser]

JD-EE :ok:

All

I apologise if this has been answered elsewhere (although I have been watching carefully).

There is still a ‘hairs on the back of the neck’ flag in my minds eye that hopefully engineering/training etc might clear up.

For their (AF447) speed (and altitude), when all the ducks are in a row (all protections working), the maximum rudder deflection available is 4 degrees … right?

Let’s assume for argument that the ACARS messages being discussed (for AF447) are correct.

Not withstanding ‘the damper’, from the moment ATA 27.23 F/CTL RUD TRV LIM FAULT was in play (in concert with the other sys messages):-

Would the flight deck crew of AF447 have had 4 degrees (8 degrees in total) rudder deflection available under foot (as with all protections in operation), or would it have been 10 degrees (20 degrees in total or magnitude 2.5 greater) rudder deflection available under foot (protections degraded/lost) as has been noted from knowledgable posters on this issue?

The reason for the question I guess is self explanatory!

[JD-EE]

The Chaser (http://www.pprune.org/members/300531-the-chaser)

That is out of my area of competence. I know electronics not flight control. So take the following with a HUGE dose of question. {o.o}

I have noted three possibilities in discussions.
1) It remains as it was until the slats are extended.
2) It opens up slightly until the slats are extended.
3) It opens up all the way.

I BELIEVE that option 3 has been discarded and either option 1 or option 2 is the case. So far I don't know that an A300-340 expert has said anything definitive.

I PRESUME that the pilots would be aware of this change from the alarms given and have experience with the ALT rules at least in the simulators. So it is somewhat premature to decide they over-controlled and lost the entire VS assembly rather violently even if other observations vaguely suggest the VS was lost at altitude. We just do not have enough hard data to even make crazy assumptions.

[1sloth]

here is what translate.google.com gives. It's slightly more readable

This has already been posted/deleted here.

Readable? Perhaps, but unreliable, e.g: google makes a nonsense of the reference to AoA vane (therefore, what else . . . ?)

[SASless]

If one adjusted EPR's to Turbulence Penetration settings and maintained attitude manually using the standby ADI....how many reasons why that would not have worked. Can these things not be hand flown.....to that extent?

[RobertS975]

ACARS may indeed be a "messaging system" and not a FDR as several astute posts have pointed out, but there also exists the possibility that very similar message sequences have been seen by AF (or other carriers) before on other flights that obviously did not crash. Maybe AF (or other carriers) has seen a similar ACARS message sequence several times previous to AF 447 and knows what flight conditions produced that sequence. If this type of ACARS message sequence or partial sequence has indeed been seen in the past, I would suspect that those crews will be further debriefed to see what else can be learned. The CVR/FDR may never be recovered in this instance. Analysis of the debris/wreckage that can be recovered along with analysis of what could produce those ACARS messages may be all that there is to solve this tragedy.

[Rananim]

Safety Concerns,
Had the VS caused this accident there would be 1001 more messages. Those messages arent there.

Arent you just doing what Will Fraser accused you of doing before?
Can you reconcile your claim with post #1180?

[Safety Concerns]

It would also help if people who only read books but have no hands on experience of the A330 would also post economically otherwise their usually respected posts may be discredited but also send people in the wrong direction.

Hopefully this extract from the a330 MM will make things even clearer.
The first extract is from the CMS chapter (Central Maintenance System)

(2)
Links between CMCs and System BITEs

Two operating modes characterize the CMS (BITE + CMC): the normal mode and the menu mode.
(a)
The normal mode

This mode is based on permanent real-time memorization of fault data.

The next is from the CMS chapter on fault reporting via acars



General rules for CMC and systems data transmission -

-
automatic transmission from the internal logics
The automatic transmission:
. of the warnings and faults in real time


yes some minor systems report faults only when asked. The systems reported as faulty on AF447 were reported in real time. Any other scenario would have ensured that acars sent other real time collected messages.

Therefore the time of transmission is irrelevant as the faults are time stamped in real time and sent in real time. If there are any communications issues the time stamp remains time when fault occured.

[aguadalte]

If one adjusted EPR's to Turbulence Penetration settings and maintained attitude manually using the standby ADI....how many reasons why that would not have worked. Can these things not be hand flown.....to that extent?

Not related to your question but, just for clarification:
EPR must be disregarded when flying unreliable speed indication procedures. One has to use N1, (and ATT) because EPR may well be also "influenced" by the severe weather conditions (if and when that is the case).
V.

[hellsbrink]

As layman I keep asking myself why the black boxes data ain't being sent to a central computer on Earth via satellite

Apart from how a Sat signal can be disrupted by a storm, if the antenna is at the wrong angle, You have to send from one place on the planet to another and it has to be bounced over several sats/ground stations........ Every down/uplink is a weak spot.

Sorry, but I think this is something else tht has been explained before. Sat signals can be disrupted easily by a storm (would have worked well IF AF447 flew into one, wouldn't it), as I am sure we have all seen live sport broadcasts "break up", we've seen Sat TV break up because of local weather and, if you have a GPS, you'll have seen that lose the signal too depending on local weather. All you need is a good storm in the way of one up/downlink station and you don't get a thing transferred from the Pacific to Paris (or, in this case, the Atlantic to Paris)

[ClippedCub]

Can I just confirm that the ONLY supporting evidence leading posters to discuss a VS mid air break up is the fact the French Navy found it in the water?

VS found intact with rudder attached. Speculation is that it was found that way because it contacted the water without the airplane. Inconclusive if VS being found alone is what caused the breakup, or is an artifact of the breakup.

Other evidence supporting in-flight break-up is the condition of the bodies, and the dispersion distance, which is similar to the China 911 flight and the Japan 707 breakup in 1966 at Mount Fuji.

These events can also be explained by a controlled, upright, low energy ditching, with crosscurrents and winds accounting for dispersion.

Consider the odds of a low energy ditching at night in a thunderstorm, with high seas, with compromised systems.

[PJ2]

Safety Concerns;
Therefore the time of transmission is irrelevant as the faults are time stamped in real time and sent in real time. If there are any communications issues the time stamp remains time when fault occured.
Determining time stamps is the key as we know. I was going on the statement from the AMM concerning the FIDS:
Fault Detection at each AFS BITE

(1) Data descrtipion

a) Triggering event
A triggering event detected by the BITE function of a computer corresponds to a change in state of a functional variable of the application software of this computer.
This event triggers a fault isolation and memorization process. In order to avoid unwanted triggering of this process, the change in state of the examioned variables is only taken into account after a certain confirmation time dependant on the variable in question.
Thus, I think suspending judgement that the ACARS is the map of events as they unfolded. I think it is risky to assume otherwise until either case is examined and determined.

As can be seen, there is much more to this process in the AMM than can, or should be re-presented here. If the messages are time-stamped at the time the failure first occurs and the ACARS messages are indeed a sequential map of failure, that will obviously assist greatly in mapping downstream effects of the various failures, which of course is the attraction. My intent is to merely esablish this mapping, either affirming or refuting the view expressed, (as I'm sure you know). Many thanks for continuing the collegial discusssion in this vein.

[NimSim]

Just for interest I put the Nimrod simulator into a climb between F350 and F370 and then blocked the starboard pitot tube. The airspeed and the mach number rose rapidly and the pilot raised the nose to bring the speed back which made the (apparent) overspeed worse. The correct IAS was shown on the port instrument panel but the mach number (which is driven by the same source as the stbd instrument) continued to show the very high mach number. The pilot closed the throttles and deployed the airbrake. There was then some stall buffet which the pilots misinterpreted as mach buffet, and so on (the artificial stall warning does not work well at this flight level). The mach protection then operated, giving a pitch up which made matters even worse. It is a very different aircraft, but it shows how little reliable information you have got in these circumstances. When teaching pitot static diagnosis I usually advocate levelling off, as it at least stops things getting worse. But if the problem is on the static side, this too is difficult.

[Safety Concerns]

with respect pj. my main aim in hammering home the acars point is to stop this nonsense about a vs departing the aircraft first.

One can determine that the vs was fixed in place due to a complete lack of real time messages relating to a whole range of other systems that would shout fault immediately.

The problem with reading the manual without the specific aircraft experience is that you can read more into a technical statement than is actually there.

I can assure you that a departing vs would excite the fids to such an extent it would shout fault in real time

As to the rest of the sequence of events I may even agree with you

[Hiflyer1757]

Nimsim tks for your post....it brings to mind has anyone seen any results of any a330 sim rides trying to recreate the incident based on what is out there so far from the weather and the acars mtc messages?

[testpanel]

Nimsim tks for your post....it brings to mind has anyone seen any results of any a330 sim rides trying to recreate the incident based on what is out there so far from the weather and the acars mtc messages?

All very true, but....
How many times did we do a sim-ride/check/re-current and the sim (read computer!) was not programmed to behave the same as the A/C would in real life. Again; the outcome of a computer depends on a) how you program it you want to behave (software written) and b) what you insert as an input to it.

I´ve done many sim-sessions and sometimes "the sim" comes with a outcome thats is/could/should-not be realistic to the real A/C..

My few cents......

[1sloth]

HiFlyer 1757,

Did you not read this (http://www.pprune.org/4987398-post1048.html)?

[cesarnc]

I saw this information in a Brazilian blog, hosted in a very well appraised newspaper's website (Jornal do Brasil).

It says that people involved in the retrieval of the bodies, said the remains are being found mutilated and without any piece of clothes.

According to them, the absence of clothes indicates an explosive decompression due to fuselage rupture, in which the huge air blow into the cabin would be able to triturate the clothes even if the person got his seatbelts fastened.

I would appreciate comments on whether or not the recovery of bodies without any closes is indeed an indication of explosive decompression

If so, it's an important piece of information.

[lomapaseo]

1sloth

HiFlyer 1757,

Did you not read this?

Possible misunderstanding here.:confused:

My read of the various posts is that the Simulator scenario only showed that the Sim would place the aircraft in a very difficult situation probably leading to breakup.

It is not programed to reproduce all the system and structural degradations that might happen in real life.

[HarryMann]

It says that people involved in the retrieval of the bodies, said the remains are being found mutilated and without any piece of clothes.Bodies were found this way in the Comet disasters...

At first assumed the decompression or fall from 30,000 + feet was the reason. Subsequently it was established that the lack of clothes was caused by lapping waves that effectively (and surprisingly), stripped them...

It was also established that in an explosive decompression the majority suffered skull fractures (within 0.2 seconds), but that severe injuries to limbs was a result of impact with the sea.

Nothing was ignored in Sir Arnold Hall's comprehensive RAE Farnborough investigation into those (first jet airliner) disasters and it was ALL published for the world to see.

[thomasfo]

Working with fail safe systems in another business there is one thing I do not understand that maybe someone can answer;

The pitot tubes are obviously important enough to put 3 of them on the a/c to make sure that you have backups. But, why would you use 3 of the same brand/type/design? When the a/c is built, I even bet they come off the same production batch. If there is a design flaw or malfunction, you have a much higher risk to face problems with more than one if they all are the same. It is a bit like putting two new halogen lamps in your car, with today's automated production they will probably fail at about the same time. If there is a problem with icing in the pitot tubes, they will probably experience the problem at about the same time if they are built equal.

So, why not use at least two designs/brands ?

[Hiflyer1757]

Got that in an email from senior cockpit crew at a major US carrier yesterday...did not see it posted here :O.....and the email was as 'washed' as the post of detail such as what type of sim and when was it run which could give an idea of what data they were working with.

The results they got in those 'rides' is chilling but I would think there has been more than that run around the world....would like to see the variables and the subsequent results for comparison. Absent recovery and download of data from the boxes these sim runs could provide a 'next best' look into possible causes.

This incident, down the road, could have a long term impact on future aircraft automation for manufacturers and suppliers in regards to flight into severe weather as well as a possible 'relook' of systems already certified IMHO....for all manufacturers and suppliers.

[Mad (Flt) Scientist]

thomasfo

There's a thread specifically on the issue of air data sensing here (http://www.pprune.org/tech-log/376881-technical-alternatives-pitot-tubes.html) in the Tech Log forum with some info on this issue.

One issue with a dissimilar design is that it becomes quite hard to ensure similar performance from dissimilar designs, which makes it more difficult to monitor for errors between different types of sensor, as the "error" may not be due to a failure but simply the expected issue. Since errors between different air data systems can be quite important for things like RVSM performance, this isn't a trivial issue.

You also have to remember that all probes,even if differently sourced, would have to be to a common specification. If the aircraft then encounters conditions outside those covered by the spec, even dissimilar probes could fail together.

[HarryMann]

So, why not use at least two designs/brands ?

Sometimes they do, at least different releases of the same product...

And having proved the performance (of said item) in extensive tests, you wouldn't want misreading when cross-comparing or calibration issues.

[cesarnc]

Bodies were found this way in the Comet disasters...

At first assumed the decompression or fall from 30,000 + feet was the reason. Subsequently it was established that the lack of clothes at least, was casued by lapping waves that effectively (and surprisingly), stripped them...


Well, then it's not conclusive by itself. They will have to couple with the state of the debris recovered...

Understandably officials and the media are not broadcasting "nude mutilated corpses" and also they are not giving details about the debris to avoid a thunderstorm of misinterpretations.

[Checkboard]

So, why not use at least two designs/brands ?
So all three strand steel cables should be replaced with cables made from three strands of three different metals :confused: :rolleyes:

[Will Fraser]

Tied sneakers leave the feet at three G. Consider not the decompression, but the freefall at 400 knots through the atmosphere. Not all our people stayed inside a disintegrating fuselage. At 200 knots stick your paw out the little vent window of the 402. Actually, don't, just put your finger tip into the airstream, and hopefully you'll pull it back with its fingernail. A Tornado at 250knots will disintegrate a Cadillac, at 400 knots?

[barit1]

Yes - NWA 727 on ferry out of NYC had exactly this problem (1 Dec 74) and the outcome was as PTH and NimSim described. If anyone has access to full NTSB reports, the # is NYC75AN070.

[ClippedCub]

Not going to post the details here so everyone can stay focused, but look up China Airlines Flight 611 - decompression at 35k ft. Some of the details you don't want to know, but it supports clothes being ripped off.

Ballistic trajectory analysis; (didn't read the whole report, don't think this particular pdf contains passenger status)

http://www.asc.gov.tw/author_files/Ballistic.pdf

[Will Fraser]

pth You speak with the sound of direct experience, and I appreciate that. I simply won't demand anyone look at anything as conclusive. At this point it is absurd. I think you are right, and I think I'm right. The point by point is yet to be, but there's enough to have a dread. 587 was climbing at low altitude, 447 was cruising at Mach .80 (at Least?) at 35,000 feet.
The lonely VS/Rudder tells a tale that is hard to ignore.

Will

[rigpiggy]

As far as the ACARS messaging if they could send out an acars message they could easily send out a gps position on say a 5 minute interval.

[HarryMann]

No Will...

I have already answered that... the fall does not always remove clothes, certainly not at free-fall 170 mph. Which is why I used the term 'surprisingly'

But why had the bodies been found in such different states of undress? To find out the experts dreamt up a test as elaborate and detailed in its way as the experiments on the Comet (airframe) itself.

With plastic & sorbo-rubber they made eight life-like dummies whose limbs moved as freely as any human's and dressed them like ordinary aircraft passengers in underwear, shirts, two- and three piece suits or sports jackets and trousers cut from cloth varying from tweeds to worsteds and even ties and socks to match. But the attention to detail did not end there: they went so far as to inject some of their own travelling habits into the experiments, like undoing the bottom waistcoat buttons on some of the dummies, giving one a fawn woolen cardigan, another a sleeveless grey pullover, and so on. And then, just to add that extra touch of realism, they undid the clasp and top two buttons of the eight dummy's trousers like a man who likes to loosen his belly for travelling.

The plan was to drop the dummies from aircraft flying at different altitudes to see what effect the fall and impact with the ground to see what the fall and impact with the ground would have on their clothes. the first one was pushed out at 10,000 ft and only lost a shoe - on impact!
The second went out at 12,000 ft, lost ashoe on the descent and another when he hit the ground. But his clothes stayed on.
The third, fourth and fifth dummies were dropped into ten feet of water off Pendine Sands in wales. they were left to float, however, until the ebbing tide left them high and dry. Not one lost his clothes in the 12000 ft drop, but when they were picked up some time later all showed signs of losing them - the third in moderation, the fourth and fifth without question. For some unaccountable reason, number five's cardigan & trousers were torn to shreds, although his sports jacket, found well of the shoulders and half-way down the body, was hardly damaged.

The last three dummies - six, seven and eight - were packed into the bomb compartment of a high-flying bomber and dropped over land from 30,000 ft, the height at which both Comets were believed to have come to grief. All were badly damaged by the impact with the ground, but though they dropped a distance of nearly 6 miles and reached a speed of 170 mph, none lost his clothes; and unbelievable though it may seem, none of the garments was spoiled.

From these observations, Farnborough naturally concluded that th Comet victims had not been unclothed by the fall, but that lapping waves of the Mediterranean had undressed them. Slowly, the pieces of the complex Comet jig-saw puzzzle were beginning to fit into placeAdmiited, people dress differently and lighter today, but then the bodies inthis case were in the sea longer than the Comet disasters, and a much rougher sea too!

[Yipoyan]

Assuming that it was pitot-static system icing;
Assuming that airspeed indication became unreliable;
Assuming that AF447 entered into a spiral dive;

What would/could you do as the pilot to get out of the situation?

What could we learn from this unfortunate accident?

[Will Fraser]

Harry, there is a difference between accelerating to terminal velocity and decelerating from 400 knots to Terminal velocity.

[HarryMann]

Indeed Will...

But then I see no reference to them being dropped from a hot-air balloon. They were dropped from a bomber, perhaps a V-bomber's bomb-bay, travelling at that sort of speed - though there is no specific information to that effect other than it was a 'high-flying' bomber - 30,00 ft is too high for a piston engined bomber, so humour me and assume it was a V-bomber and at speed not about to stall...

They did however seem to be pretty sure that 'lapping' waves can 'surprisingly' undress someone in a couple of days, as they weren't denuded after a fall.

So if it really matters, we can conclude that we can't conclude what did it - if the reports are correct, which I imagine they basically are.

PS. I was just simply adding some (rarely) known facts to a previous question about their reported clothing states

[agusaleale]

<H2>10/06: Glide Slope - AF447 - Agora é certo: jato se desintegrou no ar (http://www.jblog.com.br/slot.php?itemid=13389)
Postado por: marceloambrosio (http://www.jblog.com.br/slot.php?memberid=6)

00:34

A coleta dos corpos é uma parte dura da missão de resgate e que exige um preparo emocional e psicológico muito grande por parte dos militares envolvidos na busca pelos destroços do A330. Em acidentes aéreos graves, esse trabalho exige um esforço físico brutal e um autocontrole impressionante. Conheço vários militares da FAB que atuaram nesse tipo de missão. Alguns me disseram que torcem para que a busca por corpos nos destroços se dê em uma área carbonizada pela explosão da própria aeronave - o fogo higieniza o ambiente, eliminando os insetos e os odores da decomposição. Isso não ocorreu, por exemplo, com as vítimas do desastre com o Boeing da Gol no Mato Grosso, cujo drama final envolveu um mergulho em parafuso encerrado já perto do solo, quando a estrutura não aguentou a força G da curva e se partiu em vários pedaços grandes. E o trabalho do Salvaero ali foi um dos mais difíceis já realizados, completado com um resultado impressionante: todos os corpos foram recuperados após meses de árdua tarefa. E tempos depois, os peritos que precisavam avaliar os destroços ainda encontravam um ambiente impossível de atuar.

No acidente com o A330, a água substituiu o fogo nessa relativa preparação do ambiente para as equipes de resgate. Mas mesmo assim, segundo militares envolvidos, o recolhimento dos restos mortais de passageiros e tripulantes - o uso da palavra corpos é uma janela semântica para horrorizar menos quem precisa acompanhar o processo ou chora pela perda traumática - tem sido uma penosa sucessão de chocantes reproduções da violência da tragédia. Um dos militares com acesso às equipes de resgate me contou que os corpos estão muito mutilados, vários se apresentam desmembrados e sem cabeça - restando apenas o tronco - e irreconhecíveis por características visuais. A definição da identidade se dará mesmo pelo DNA. Em alguns pouquíssimos cadáveres, mais preservados, os militares já encontraram a primeira e definitiva versão para os instantes finais do vôo AF447: corpos completamente nus confirmam que o Airbus se desintegrou no ar antes do choque com o mar. Se os cálculos da razão de descida - que em condições normais fariam o jato bater na água a 215 km do ponto inicial de alarme, e não a 70 km - mostravam um angulo elevado de mergulho, a prova cabal e técnica está nessa descoberta.

De acordo com especialistas em resgate, um dos principais indicativos de uma despressurização violenta decorrente de ruptura estrutural é encontrar corpos sem qualquer peça de roupa. No acidente de Mato Grosso, alguns assim estavam presos em galhos de árvores. A explicação traduz bem a aterradora experiência: quando a cabine se rompe, a descompensação na pressão provoca uma enorme corrente de ar, que arrasta partes do interior da cabine mesmo que estejam firmemente presas ao chão. Cadeiras, forros de paredes, estruturas das janelas, painéis do teto, enfim, tudo é arrancado numa implosão. O repuxo ainda rasga e tritura todas as roupas das pessoas, mesmo que estejam firmemente amarradas nos assentos - que só resistem por pouco tempo. O consolo, se é que se pode dizer assim, é que a morte ocorre em poucos segundos. Pelo menos no caso desse corpo encontrado sem todas as roupas, a passagem para outra dimensão serviu para elucidar mais um capítulo dessa trágica etapa da história da aviação.

</H2>

The collection of bodies is a hard mission that requires an emotional and psychological preparation for the soldiers involved in the search of the wreckage of the A330. ....




In the accident of the A330, ... one of the soldiers that has access to teams of rescue told me that the bodies are mutilated, without legs and arms and even without head - leaving only the trunk - and visually unrecognizable . The identity will be made by the DNA. In a few corpses, preserved more, the soldiers realized the final moments of flight AF447: completely naked bodies confirmed that the Airbus disintegrated in the air before the impact with the sea. If the calculations of the rate of descent ( which under normal conditions would have made the jet hit the water distant 215 km from the starting point of alarm, not to 70 km) - showed a high angle of dip, and this is a proof of the discovery.


According to experts in rescue, a key indicative of a violent depressurization due to structural breaks is to find bodies without any piece of clothing. At the accident of Mato Grosso, some bodies were found like that in the branches of the trees. The explanation reflects the terrifying experience: when the cabin is broken, the decompensation in pressure causes a huge current of air, which pulls into the interior of the cabin even if they are firmly stuck to the floor. Chairs, lining of walls, structures, windows, panels of the roof, finally, everything is pulled out in the implosion. I alsol rips and grinds the clothes, even if they are strongly tied to seats - only resist for a short time. Death occurs in seconds. At least in the case of the body found without any clothes, the transition to another dimension served to clarify one more chapter of this tragic step in the history of aviation



I underline THE, as during the blog the author makes us believe that all were found without clothes, but later he says THE, implying only one.

[HarryMann]

According to experts in rescue, a key indicative of a violent depressurization due to structural breaks is to find bodies without any piece of clothing. At the accident of Mato Grosso, some bodies were found like that in the branches of the trees. The explanation reflects the terrifying experience: when the cabin is broken, the decompensation in pressure causes a huge current of air, which pulls into the interior of the cabin even if they are firmly stuck to the floor. Chairs, lining of walls, structures, windows, panels of the roof, finally, everything is pulled out in the implosion. I alsol rips and grinds the clothes, even if they are strongly tied to seats - only resist for a short time. Death occurs in seconds. At least in the case of the body found without any clothes, the transition to another dimension served to clarify one more chapter of this tragic step in the history of aviation

Lots of mistranslations or inaccuracies in that, but the facts hardly bear poring over... everyone dead in Comets in 2/10ths of a second was the estimate based on dynamic similarity models - fundamentally skull fractures or heart effects.

[protectthehornet]

YIPOWYAN

I don't know if I would let a plane get into a spiral dive, but if my pitot was bad I would fly known attitude and power settings...and accept sloppy altitude control until things got sorted out. I would keep the wings level on the attitude gyro, confirming my wings were level by not changing heading too much.

something has happened to pilots that don't know how to get by with partial panel...

One of my first jobs as a pilot required a real NDB approach without a heading indicator or attitude indicator...using only the compass (whiskey as it was known) and turn and slip.

while jets would be really hard to fly like this, certainly knowing that you climb at full/climb power with fifteen degrees of pitch, you are level with nose up one degree and cruise power and so forth should be part of any pilot's bag of tricks.

konwing that you are making a normal approach with nose about level, gear and flaps down and power at X should be in your bag of tricks too.

I think I will renew my CFIIMEI and charge 200US$ an hour for basic instructions.

[cesarnc]

@agusaleale (http://www.pprune.org/members/155378-agusaleale)

That's exactly the blog I was talking about.

But, apparently (as refused before by other members), bodies found without their clothes are not conclusive of explosive decompression..

I brought this up previously because it wasn't mentioned by officials or the media (understandably) as well as this blog is hosted by an appraised newspaper in Brazil...

[p51guy]

Once a month or so out of Miami I would go to a partial panel scan on the B757 using just whiskey compass, standby airspeed, standby altimiter and standby horizon to fly for a few minutes to get back to basics if everything ever failed. Even the standby attitude indicator wasn't required on the southerly heading because of the compass lead error. That is all I had in the aeronca champ I started with so hope I can still fly with it now.

[madrock]

For all the newly qualified forensic pathologists stoking the discussion regarding information contained "in a Brazilian blog", would it not be more respectfull to leave that in the capable hands of the on-scene specialists ?

[WhyIsThereAir]

> As can be seen, there is much more to this process in the AMM than can, or should be re-presented here. If the messages are time-stamped at the time the failure first occurs and the ACARS messages are indeed a sequential map of failure...

Be very careful with the thought "time-stamped at the time the failure first occurs." Because it is wrong.

The fault is time-stamped at the time it is first RECOGNIZED as a fault. The fault is recognized at some (unknown to us) time after it has occurred. As described earlier in the excerpt from the AMM, the time it takes to recognize a change as a fault depends on a filtering time, and this filtering time will be different for different variables. We do not know what this time period is, thought it will generally be fractions of a second.

That is enough to cause one fault to be RECOGNIZED before another fault, even though the second fault might have OCCURRED first. Thus, the messages may arrive somewhat out of order of fault occurance.

(I believe also the messages we have seen only have a timestamp that is good to one second resolution. A lot happens in a second. If the message transmission order becomes scrambled (as can easily happen in a noisy environment) we can only reconstruct the original message order to the resolution of the timestamp. This can lead to erroneous conclusions.)

[Mad (Flt) Scientist]

I believe also the messages we have seen only have a timestamp that is good to one second resolution.

Actually, I believe the messages in the now widely distrubted ACARS list are only timed to a one minute resolution. WN0905312245 for example being 2245 on 31 May 2009. No mention of seconds.

So the presentation is at an order of magnitude or two less resolution than the actual message handling.

This would tend to suggest that
(a) we can assume that all the "0210" messages relate to faults before those with an "0211" identifier, etc., because the only way for them to be mixed up is for a fault at 02:10:58 being identified and reported 3 secs later (and thus getting an "0211" identifier) while a later fault at 02:10:59 gets recognized and reported within a second, thus getting an "0210" identifier. Since I think it's likely that the recognition times are under a second in most - but not all cases - and given the unlikelihood of the events being at the critical "minute rollover" it seems a reasonable assumption.
We certainly CAN assume that messages with more than a one minute difference are in the noted order - so all the "0210" must be before the "0212" and so on.
and
(b) we cannot rely on the presentation order for messages in a single identifier group ("0210" etc) because near simultaneous faults may have been swapped by a different recognition delay.

Actually, looking at the version I have here, there does in fact seem to be one message out of order. I suspect its a transcription error from the TV screenshots.

[WhyIsThereAir]

> One can determine that the vs was fixed in place due to a complete lack of real time messages relating to a whole range of other systems that would shout fault immediately.

One can determine the VS was in place during the time the messages were sent by a far simpler test: the messages were received. Talking to a satellite requires a moderately stable platform. There are slew limits on how fast the antenna can track, even if it is a patch antenna or electrically steered antenna. The antenna has both pitch and roll limits and pitch and roll rate limits. It may also have limits on altitude change rate.

Mental excercise 1: Take a craft in stable level flight under AP. Remove the VS. What will happen? How long will it take to happen?

Mental excercise 2: Take a craft in 'strong turbulance' in alternate law with no airspeed indication and no visual clues, being hand-flown reasonably stably. Remove the VS. What will happen? How long will it take to happen?

I submit that we KNOW the VS was present and functional at 02:14. We know this because messages were sent (and received) that were timestamped at 02:14. They would not have been able to be sent (or at least received by the satellite) if the craft had not been reasonably stable in reasonably level flight.

We do not know what happened after 02:14.

[tquehl]

I am also dismayed at the tangents this thread has taken. All speculation, especially concerning the vertical stab. It is obviously apparent that the VS was found due to three possible scenarios:

1. It departed the airframe at altitude and either caused or contributed to the possible inflight breakup.

2. It left the airframe after the airplane departed controled flight due to compounding failures and systems problems.

3. It was seperated upon impact with the Atlantic Ocean.

In all scenarios above, it was only discovered fairly quickly because it floated. It floated is all we know at this time. Fairly simple.

Of course this is "the" topic in aviation and airline ops at this time, however the total lack of knowledge expressed by some/many posters here amaze me. I can certainly pick the fly **** from the pepper and realize who the true professional aviators are in the postings.

Are we now going to have witch hunts and place perfectly good airframes on the ground circa 1979-1980 with the DC-10 that put Sir Freddie out of business for no sane reason? The accident is an anomaly, which is why it is both an accident and hard to discover the cause.

I watch the thread daily and I truly understand the want for information. I would suggest to the mods that this be broken out to threads that require different levels of certification or expertise for participation.

Over

[cesarnc]

For all the newly qualified forensic pathologists stoking the discussion regarding information contained "in a Brazilian blog", would it not be more respectfull to leave that in the capable hands of the on-scene specialists ?


Well, in this case it would be as respectful to leave the whole investigation in the capable hands of French authorites and shut down the thread, no?

Several information shared here comes from leaked documents, raw pictures and information from the media. "In a Brazilian blog" is not by any mean less trustworthy than those...

[Rigid Rotor]

Here's an excerpt from an article in CNN on-line by Kieran Daly:

"An iced-up Pitot tube deprives the pilots and the aircraft's automatic systems of airspeed information, making the aircraft much harder to fly and preventing numerous onboard functions from working properly -- a highly plausible explanation for the string of error messages sent by the aircraft shortly before the crash.

As it happens, an unusually detailed account of what happens in those circumstances has turned up in the form of an internal memo written in French last December by the safety office of the small airline Air Caraibes Atlantique, which suffered the phenomenon twice in quick succession.

They called a meeting with Airbus in which the airline's flight managers pointed out not only what had happened, but also the difficulty of understanding the immediate actions that Airbus recommended pilots should take. I've read it, and it is decidedly confusing.

Now picture the crew of AF447 struggling with that unfamiliar checklist at night, in a cockpit hammered by severe turbulence, possibly lightning, with no airspeed information and numerous warning lights and alarms sounding.

It is difficult to imagine many bigger challenges for a pilot, and anything short of near-perfect execution would have the potential for loss of control.

But the fact remains that this is today speculation."

[lomapaseo]

The lonely VS/Rudder tells a tale that is hard to ignore

Only if you can read tea leaves.

The damn thing floats the rest of the stuff it was attached sunk. The fracture lines tell the story but I have no interest in jumping ahead of those with access to better photos.

Each part of the plane that hits the ocean does so at its own terminal velocity (aerodynamic shape) The attitude of the impact with the water results in hydraulic loading. Some of which will be obvious (as was TWA800).

There is much to be gleaned by the experts.

[DorianB]

WhyIsThereAir, you said:

One can determine the VS was in place during the time the messages were sent by a far simpler test: the messages were received. Talking to a satellite requires a moderately stable platform. There are slew limits on how fast the antenna can track, even if it is a patch antenna or electrically steered antenna. The antenna has both pitch and roll limits and pitch and roll rate limits. It may also have limits on altitude change rate.

I am in the RF world...and for some reason I thought the Satcom antenna was a phased array antenna....therefore requiring no steering or any 'lock on time'...it simply needs to stay within a certain degree of vertical. That being said, if it is a phased array antenna and the aircraft become inverted or went in to an especially deep dive then no messages would transmit during such period.

I could be wrong about the antenna type...but after this thread and the other...reading several thousand posts...the antenna could be made of paper mache in my head by now. ;)

[Captain-Crunch]

Thank you "Safety Concerns" for that important post. I have to question a comment my colleague made which said:

The reason for such caution is, among other reasons, the fact that the ACARS is a maintenance reporting and messaging system, not a flight data analysis tool. The granularity of the data is very high, (stating the obvious).

While a good point, I'm not sure what he means by "granularity." :confused: I was under the impression that the most, if not all of the data path is digital, not analog on it's way up to the satellite. This means it is of a highly accurate and known behavior: we know the program, the version number and the data error bit checking subroutines that will not report the message if it is fragmentary (unlike micorsloth products which are not allowed in flight.) Error reporting of LMU items is very reliable stuff AFAIK: FAULT: The component experienced a subroutine shortcomming or a lack of signal that it needs to do it's thing. A fault occurred (not necessarily a complete failure or even a power loss). Some faults cause other faults in units that were depending on data from the upstream unit. This is my understanding of the process.

Mr Faser's attempt to delve into the aerodynamist's world of high speed, high altitude aerodynamic cause and effect sequences is ill-advised imho. These things do not have probable outcomes, even for a supercomputer. This is why most of the designs are scrapped at Edwards and Dryden after flight testing concludes, that for unknown reasons, the airfoil section when introduced on this particular airframe in this way behaves differently.

On the Rudder at altitude: whether or not a Yaw damper function was involved, or the pilot was involved is impossible to say. Airbus posters here suspect that yaw damping was available since in that alternate law mode it is still supposed to provide protection from dutch roll. My earlier comments were in the context of complete loss of yaw damping. I don't feel that's the problem now that Alternate Law has been explained to me.

All we should say for sure is that it appears the forward bolt hole of the VS yielded and the next two attach points did not, as evidenced by the attached lug carry though hardware. I wouldn't expect the VS/Rudder assembly to survive this way, attached and in good shape, if it was still attached to the airplane at sea level. But strong circumstantial SITA (french product for ACARS) data indicates it was attached at 0214z since the HF antenna coupler did not fault. (The SATCOM however, likely had it's own integral GPS for acquiring lock, I'm told, so this is no longer plausible evidence for an IRU platform available: hence ATT info.)

Seeing the same components faulted on other a330 mishaps is strong evidence. AB emphisizing unrelable airspeed preparedness is very suggestive that they feel this is the problem. Reportedly, the CEO said he doesn't think it's the pitot tubes. I don't either. Even though I think they all iced up, I suspect it's really the A330's interpretation of a complete loss of all air data that caused this accident. I had a number of accidental thrust latches on the FMA on the A310, where the AFS took the wrong action and required us to disconnect it.

Unfortunately, it appears I have sired a number of Captain experts with a total of one post. While they could have been banned for taking unpopular positions in the past, their posts suggest they have no experience flying in weather at altitude. I would suggest that from now on, that anybody with the title of Captain in his screen name is automatically suspect. :E

Yes including me. Feel free to challenge me on anything.

Cheers,

CC

All the above, is only my opinion only, and I could be wrong.

[misd-agin]

Picture of an A310 vertical stabilizer, after impact with water at approx. 215 KIAS, can be found on page 98.

Looks indentical to the AF 447 vertical stabilizer.

http://www.bea-fr.org/docspa/2000/5y-n000130a/pdf/5y-n000130a.pdf (http://www.bea-fr.org/docspa/2000/5y-n000130a/pdf/5y-n000130a.pdf)

[einhverfr]

Yes - NWA 727 on ferry out of NYC had exactly this problem (1 Dec 74) and the outcome was as PTH and NimSim described. If anyone has access to full NTSB reports, the # is NYC75AN070.


Just to be helpful, the report can be found at ASN Aircraft accident Boeing 727-251 N274US Stony Point, NY (http://aviation-safety.net/database/record.php?id=19741201-1)

[Roastbeef99]

(lapsed student pilot here, but lots of computerized embedded systems expertise)

Regarding the "The granularity of the data is very high" statement, I interpreted this as saying "We don't know if or how the ACARS system batches transmissions".

In communications systems there is an overhead associated with obtaining the channel to communicate data, and to maximize utilization of the channel its appropriate to make the overhead (from a overall channel perspective) as minimal as possible. So the ACARS system might not transmit a single notification as soon as it receives it from the onboard systems... Hypothetical: Upon getting a notification it could set a countdown timer for 2 minutes, and when that 2 minute timer expires it transmits the original notification and anything else it receives in that two minute period. This is perfectly acceptable given what ACARS is intended for, and makes the overall communications system more efficient, but it also means that: a) The timestamps might not reflect the *exact* moment something was detected, rather it's a close approximation to the time. and b) There might have been unsent notifications in the ACARS system that never got transmitted (even if the transmitter and antenna stayed intact all the way til the end)
-RB

[FE Hoppy]

Picture of an A310 vertical stabilizer, after impact with water at approx. 215 KIAS, can be found on page 98.

Looks indentical to the AF 447 vertical stabilizer.

http://www.bea-fr.org/docspa/2000/5y-n000130a/pdf/5y-n000130a.pdf



misd again:

It's on page 122 and it looks nothing like the AF447.

[Graybeard]

CC: "I suspect it's really the A330's interpretation of a complete loss of all air data that caused this accident."

The ACARS reported ADR fail, which could mean any one or more of the outputs of the ADR: airspeed, altitude, CAS, TAT, etc. . The pitot tubes on the A330 feed only airspeed computation, and airspeed is all that had to fail to lead to this accident. Altitude Fail in addition to airspeed fail is really, really tough to overcome. There was probably not a loss of altitude data, and I see no indication there was, except for the TCAS, which could be explained differently.

Do you see any other evidence of Altitude Fail?

GB

[Lost in Saigon]

misd again:

It's on page 122 and it look nothing like the AF447.

From page 122: http://www.bea-fr.org/docspa/2000/5y...y-n000130a.pdf

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

[RWA]

Checked the thread as best I could, apologies if this has already been covered.

On the Aviation Herald site, referring to this accident, there's a passage about two Air France A340s that had similar problems (thankfully without such a tragic ending) which says:-

"The captain released control of the airplane to the first officer and tried to switch his display from ADIRU1 to ADIRU3. 2 minutes later autopilot and autothrust disconnected and the fly by wire changed into alternate law. The crew noticed icing conditions (static air temperature [SAT] -29 degrees Centigrade) and switched anti ice including pitot heating systems from automatic to on. The speed indications became normal again and agreed again.........

'From automatic to on.' I'd heard that the A330/A340 have automatic pitot heating, don't know if all airliners do nowadays? But if there's an automated system controlling the pitot heaters, could it be possible that the whole cascade of 'computer malfunctions' was caused by.......a computer malfunction........?

Crash: Air France A332 over Atlantic on June 1st 2009, aircraft impacted ocean (http://avherald.com/h?article=41a81ef1/0022&opt=0)

Also - I looked through Airbus's 'advisories' as best I could, and don't recall seeing any mention of 'Check Pitot Heat ON.'

[Captain-Crunch]

Greybeard,

I have to defer to the A330 techs to tell me the likelihood of that. I'm just going on the experience that on the early bus where all three altimeters sprung into very different readings, and began to drift, so we were unsure of our altitude. We lost all air data for a time imho, and I suspected at the time that it got the static ports and tats as well.

Moral of the Story: Don't fly within 100 nm's of a typhoon near the equator or in the ITCZ with a bus. The ice won't show up on the radar and even benign looking stuff in the arm of cyclonic weather can take everything out for a short time.

And it's important to point out that this was a lot of years ago, and I'm retired now. A check pilot who did work for Boeing told me of the B-747 engine structure mistakes. Chalk it up to Test Pilot Urban Legend if you will:

[kwachon]

If the VS failed in a downward compression direction as has been intimated in preceding writings, I would think that it is quite possible that this caused deformation and damage of the aft pressure bulkhead and the speculated subsequent pressurization failure.

Comments?

KW

[avspook]

From the RC OPtion Data (SDU-906)

The SDU receives airplane heading and attitude data from the inertial reference unit (IRU). The SDU system processor determines the elevation and azimuth angle necessary to point the high gain antenna beam at the applicable satellite. The SDU sends this data to the beam steering unit (BSU).

The Anetnna is a phased arraray type It needs to know which Active elements to activate to 'Steer the beam; ( done electronically, no moving components)

If anyone knows AF's fit Manufacturer &/or High Gain/Low Gain Antenna(s) please let me know

[cpdlcads]

We tried this in the sim:

FL 350 M .81 normal law,

Quickly apply full rudder, the a/c rapidly banks to 50-60 degrees bank, with only 4 degrees of rudder travel available.

Conversely, an engine failure in cruise is counteracted with the lightest touch of rudder, maybe 1 inch and can barely be seen on the flt controls page.

Respect the rudder, it is a very powerful control.

[curious digger]

concerning the VS issue - you cannot tell if there were other "1001 msg" or not because you cannot be sure that the 02:14Z msg was the last one, or are you?

do some of the experts present here consider the backloops between adirus and computers?

[RWA]

As I understand it, cpdlcads, the Rudder Travel Limiter does indeed restrict rudder movement to 4 degrees or so at high speed. As opposed to 30 degrees or so at low speed.

BUT, it surely relies on the ASIs for the speed? If the pitot tubes were partially blocked, presumably the ASIs would understate that speed?

So could the RTL, in those circumstances, have permitted a much greater rudder deflection than was safe?

[cpdlcads]

RWA

Yes thats why with rud trvl limit fault ecam says rudder: handle with care

[Ground Brick]

avspook

It is possible, that SAT antenna was smcelectronic CMA-2102 SATCOM High Gain Antenna System.

http://www.cmcelectronics.ca/pdf/satcom2102.pdf

No build in GPS, electronically steerable, phased-array antenna, 12-17 dB gain.

[Interflug]

Yes thats why with rud trvl limit fault ecam says rudder: handle with careWhich means exactly what on a flight control without feedback? Do you have some sort of "care" marks, or artificial resistance when you reach those "care" limits? :}
CARE ON .................. CHECKED

Who has experience with careful rudder inputs flying manually at altitude at M 0.80 in alternate law?...in severe turbulence...
Test pilot territory I guess...

Not saying this is relevant. We are fishing in the dark.

[ILS27LEFT]

I have read quite a bit about this incident.
It is my personal opinion, according to the facts available at this precise time, that any other professional pilots who would have been on duty in that cockpit at that precise time, left exactly in the same scenario as the AF447 flying through that weather, would have done all possible to find a solution and fly the damn thing but whatever action would have been taken this would have resulted in a guaranteed disaster:
-Coffin corner and loss of all speed data (including GPS due to bad signal) is a recipe for disaster whatever the pilots on board.
Combine the above with a sudden and multiple list of serious faults and the plane very quickly either goes too fast or too slow, whatever corrective action is taken.
In both cases the plane would destroy pretty quickly.
If they could have precisely controlled their speed nothing would have happened. They could not guess their speed.
I am sure excellent pilots were dealing with an impossible event.
Airbus vs Boeing does not apply, any aircraft, whatever the make and model, would have gone beyond the coffin corner speed limits if flown without speed data.
Airbus was fully aware of the pitot tube problem, AF did not react.
Corners can never be cut in aviation especially when dealing with essential flying data, speed is everything. GPS signal in weather is lost.:mad:

[Dysag]

Let's begin at the beginning.
Are you sure that 'any other professional pilots' would have been flying through that weather, and not around it?

[QF2]

Dysag

I'm not sure because I wasn't there. From the information that is available so far, you really would need to be there to come to any conclusion of whether their actions were the right ones or not. What I would assume is that they were professional pilots acting in a professional manner to ensure the safe operation of the flight. If you have the specific details of the information that the pilots had in front of them and would care to share that with us, then we may be able to answer your question....

[OutOfRunWay]

I suppose it was inevitable, but Agence Presse, Reuters and others are reporting that a criminal Investigation has commenced, with focus on the pitots, and why they were not replaced.

Apparantly this is standard procedure in France if French citizens die outside the country, but we are all aware of the regrettable effects of a criminal investigation mingling with, or worse, hindring an accident investigation: many people who might have something to contribute retreat into the woodwork.

A shame, really.

Regards, OORW

[Lemurian]

Ground Brick



It is possible, that SAT antenna was smcelectronic CMA-2102 SATCOM High Gain Antenna System.

It was.

[NARVAL]

Just to give a little information on the subject (A330) of the rudder :

Rudder : Yaw damping in turbulence after failure :in case of a total loss of electrical power there remains a backup yaw damper unit completely independant (it has its own gyrometer and the electrical supply is provided by generators driven by two of the hydraulic systems.
Rudder deflection : controlled by 2 limiter channels and two SECs. If both calculators fail, the max rudder deflection available remains what it was before the failure ; that is 4 degrees in cruise. The max deflection will become available again when slats are extended.

[Professorrah]

No build in GPS, electronically steerable, phased-array antenna, 12-17 dB gain

for what it is worth, this antenna is 12-17dBi, not dBd, so it is not really a max of 17dB of gain - only against a theoretical radiator which of course does not exist, so the gain will be 2-3 dB less than the quoted gain.

[Paul2412]

Firstly, as this is my first post let me point out that I am NOT an airline pilot (although I wish I was). I do have a great interest in aviation but my experience is limited to Microsoft Flight Simulator...

I have a couple of questions:

1. If Airbus knew that the pitot-static tubes could become unreliable in a storm at high altitude (presumably, when you need them most) why did they not make the changes mandatory immediately? Thinking about the Aero Peru flight, although it was due to human error the consequences were disastrous. Even worse, if Air France knew about this why didn't they immediately replace the system? Do airlines like to gamble with passengers lives to save a little time and money? If it's proved that the pitot-static system was to blame, I can see very tough questions ahead for both Airbus and Air France.

2. I'm in IT myself, and find it increasingly hard to believe that a system that transmits data from the FDR back to the airlines HQ in real time or near real time cannot be developed. If the plane can send out warnings, why cant the critical data be sent to the ground? If this was in place, locating a tiny box in the middle of the second largest ocean in the world wouldn't be necessary.

I apologise if my lack of knowledge of real world flying has led to a ridiculous post, but I'm following this story very carefully and answers to my 2 points would be very gratefully received.

Regards,

Paul

[teropa]

Nobody has commented yet my suggestion of the encounter with very warm air.

Can somebody who knows how to interpret Tim's excellent met analysis well enough tell what the SAT would have been, had the airplane encountered a patch of very warm air inside the MCS. I am particularly interested in the idea that IF the A330 was not equipped with the Backup Speed Scale (AoA-based), that how difficult would it have been to control the airplane if at the same time warm air was present in a way that the aircraft effectively climbed several thousand feet (increasing stall speed in the process) ?

rgds,
Tero

[DC-ATE]

RWA -
"The crew [different flight, different time] noticed icing conditions (static air temperature [SAT] -29 degrees Centigrade) and switched anti ice including pitot heating systems from automatic to on. The speed indications became normal again and agreed again........."

'From automatic to on.' I'd heard that the A330/A340 have automatic pitot heating, don't know if all airliners do nowadays? But if there's an automated system controlling the pitot heaters, could it be possible that the whole cascade of 'computer malfunctions' was caused by.......a computer malfunction........?

Someone please tell me WHY, if true, there is an "Automatic" position on the Pitot Heat Switch on this, or any aircraft.

[stadedelafougere]

What's the point for an airline to receive in real time the data concerning engine thrust, rudder movement and so one. This is of no use to the company which expects its aircraft to land safely on every journey.
Yes, when crashes like that happen, we would need this data, but it does not justify implementing on every aircraft live DFDR data transmission. Besides, many A/C do not operate ETOPS flight and remain isolated from the rest of the world for substantial period of time.
Finally, Airliners would have to modify their installations to cope with all these data.

[747guru]

Paul2412

Both your points are very valid indeed!

I would love to be a "fly on the wall" listening in to the conversations between the lawyers of AF and Airbus at the moment.......talk about a blame game!

I know little about IT, but as you say, there MUST be a way that modern aircraft can transmit "burst" transmissions on a regular basis (say every 20min) to home base including ALL the info that would normally be stored on the FDR/CVR?

OK a lot can happen in the 20min between transmissions, but surely a pattern may emerge leading up to a serious incident?

[merlinxx]

Airbus folks only SVP, crew, engineers etc., maybe those with similar systems.

[kennedy]

Paul 2412,

In response to your query, it's called tombstone safety.

Tombstone satefy means that although the manufacturers, airlines and regulatory agencies know it is unsafe, (usually because us pilots have told them) it costs to much money to change that system, until there is a fatal accident that forces the change!

Hence, examples like the continued use of HF in remote areas( while the pax in the back enjoy Satcom phones and internet inflight), last time I came out of Sao Paulo into the Atlantic, we did not have HF contact with Atlantico radio for over 2 hours ( they didn't have their CPDLC turned on that night!) , and all comms were Acars thou our operations for relay to them, including wx deviations.

Cost is now the main driver of safety in the modern aviation world, and will only get worse in the future!