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AF447

Old 9th Jun 2009, 07:10
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AP disconnect

SafetyConcerns, you asked:

I have just tripped the A330 autopilot manually to off. Do I get a warning?
If yes acars will transmit it, if no acars cant transmit nothing?
On the A320 (and A330/340 will be idem), you will always get

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

irrespective of whether you disengage the autopilot manually or not.

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

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

Hope I got that sufficiently correct and clear ;-)

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

Last edited by Junkers388L; 9th Jun 2009 at 07:22.
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Old 9th Jun 2009, 07:11
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If it's naive to be prepared to consider all the evidence before leaping to a conclusion then I accept your criticism.

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

Some or all of the above may have contributed to this tragedy but I, for one, am still prepared to wait for the evidence.
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Old 9th Jun 2009, 07:17
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From the pictures released so far, I see a only section of vertical stab, I do not see a rudder!, The CVR and FDR are not located in the VS, go to smart cockpit.com and look up the A330, there you will find a layout of where things are placed within the fuselage. Lets keep things real here and based on facts as they are known thus far.

KW
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Old 9th Jun 2009, 07:37
  #804 (permalink)  
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I see a only section of vertical stab, I do not see a rudder!,
Take a look at a decent picture of an AF A330. Compare the location of the european stars with the rear of the fin. The bottom of the stars are level with the top of the 3rd blue stripe, exactly as in the photo. The Rudder is still there, its just not visible at the resolution of the photo.
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Old 9th Jun 2009, 07:37
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Fact: Most of the red stripe is painted on the rudder section.
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Old 9th Jun 2009, 07:50
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Pitot malfunction cause vs effect

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

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

I have not seen an argument supporting or contradicting that post. Most have followed the 'pitot first' event chain.
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Old 9th Jun 2009, 08:21
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That's because the 'pitot first' theory is best supported by the flurry of ACARS messages over a 4 minute period.
The total loss of ADR data is survivable, if handled correctly by the crew, so there may have been more hardship faced by the pilots before they lost control of the aeroplane. Severe turbulence and structural failure comes to mind.
Some strange ACARS messages have not been fully explained yet, like the line about the 'IR2' and the failure of PRIM1 and SEC1.

Last edited by Wytnucls; 9th Jun 2009 at 08:24. Reason: typo
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Old 9th Jun 2009, 08:28
  #808 (permalink)  
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It is time to dig out the old, cracked vinyl record and say "PLEASE WAIT FOR FACTS"

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

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

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

........

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

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

For some inexplicable reason, the BEST post since fin discovery is now in JB. Again I reproduce the bulk of arcniz's (current post #263) from JB

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

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


Most of us involved in aviation turn to THIS thread for facts, not speculation.
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Old 9th Jun 2009, 08:31
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I guess if the public had seen the picture of the VS first and days later the ACARS report, it would be the other way around and the "established" speculation would center around the VS, trying to "fit" the ACARS in.

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

Last edited by Interflug; 9th Jun 2009 at 10:17. Reason: grammar
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Old 9th Jun 2009, 08:51
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stranger than fiction

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

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

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

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

That's my 1/2 cent, delete it or not.
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Old 9th Jun 2009, 09:28
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"That would reinforce the idea that the plane broke up in flight," he said. "If it hits intact, everything shatters in tiny pieces."
A quote on the Telegraph by William Waldock, who teaches air crash investigation at Embry-Riddle Aeronautical University in Prescott, Arizona.

I was interested in the assertion itself because the VS from the XL A320 (repainted in NZ livery) at the Perpignan incident was pretty intact although the aircraft hit intact.
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Old 9th Jun 2009, 09:34
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Air NZ vs AF

I know the facts state that the tail of the Air NZ was more or less intact after impact but wasn't the altitude quite drastically different from the AF?
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Old 9th Jun 2009, 09:35
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Is the VS attachment point forward or rear of the rear pressure bulkhead i.e. would its separation lead to depressurization (hence the ACARS msg re cabin press?)
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Old 9th Jun 2009, 09:37
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Bythewayacars

STEF
JUST FOR INFO
ACARS COST MONEY!
You have to have the organisation to manage it.
Therefore a lot of "minor" Airbus airlines,
dont use it!
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Old 9th Jun 2009, 09:39
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I know the facts state that the tail of the Air NZ was more or less intact after impact but wasn't the altitude quite drastically different from the AF?
Quite so, Flyguy2006. 3000m (I think!) vs FL350.
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Old 9th Jun 2009, 09:48
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Pinkman

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

http://www.flightglobal.com/airspace...il-cutaway.jpg

Furthermore, fwd of the bulkhead there's nothing to attach it to, except the normal fuselage frames.
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Old 9th Jun 2009, 09:48
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Airbus issues precautionary telex to airlines

By: Keith Campbell 5th June 2009

source:-

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

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

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

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

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

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

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

Largely unheralded, Airbus had some good news this week, with the maiden flight of the first A330-200 destined to be converted into a strategic air-to-air refuelling tanker for the UK Royal Air Force (RAF). The aircraft was assembled at Airbus' Toulouse plant but will undergo militarisation and tanker conversion at the Airbus Military plant at Getafe, near Madrid. This specialist RAF version of the aircraft is powered by two Rolls-Royce Trent 700 engines, and 14 are on order in a £13-billion ($20,9-billion) deal.
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Old 9th Jun 2009, 09:53
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I have read every single page of the first thread and now this one. You can tell there are some very knowledgable pilots and rubbish.

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

Engineer decodes Air France Flight 447 emergency messages

Part 2 of a pod cast where a Honeywell expert goes thru all ACARS messages sent from AF447:
Innovation Analysis Group

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

Keep up the good work!
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Old 9th Jun 2009, 09:56
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looking at the acars message list there is a line with IR2, IR1, IR3, ISIS.
Which line? I can't see it
There is IR2, as reported by EFCS, IR1 IR3
and below it another message ISIS.
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Old 9th Jun 2009, 10:06
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To Swedish Steve:

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

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

Ciao
Stef
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