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AF447

Old 25th Jun 2009, 14:50
  #2301 (permalink)  
 
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Regarding Delta (NW) A330

The problem I suspect is the pitot tubes ice over and you loose your airspeed indication along with the auto pilot, auto throttles and rudder limit protection. The rudder limit protection keeps you from over stressing the rudder at high speed.
It sounds like this oversimplifys what may happen in terms of the rudder limiting.

Per the A330 FCOM Flight Controls Description:

"Rudder and pedal deflection is limited as a function of the speed. Each limiter channel is controlled and monitored by its associated SEC. In case of double SEC failure, the max rudder deflection remains at the value reached before failure ; then, a max deflection is available when the slats are extended."

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Old 25th Jun 2009, 15:01
  #2302 (permalink)  
 
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wes_wall:
Not to suggest anything, but recall, part of the crew rest module was recovered.
The crew rest module is for FA only, not to mention its damage state.
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Old 25th Jun 2009, 15:21
  #2303 (permalink)  
 
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Red coloration on the radar indicates rain intensity. Heavy rain alone does not constitute a hazard to be avoided at all costs. The same applies to heavy(strong) landing/takeoff winds, heavy snow or ice, heavy weight, heavy anything, without considering other factors.

Experience and training come into play. If the red is accompanied by steep contouring or gradient, known CB activity, known tops which cannot be overflown by several thousand feet, known or depicted significant turbulence, lightning, stage of development other than dissipating and a strong sense of smell - as in this doesn't smell right - then by all means go around it, fuel permitting. Even a partial list would suffice in order to turn around or go around.

But if you have never flown through or over heavy rain, then I would be interested in knowing what your experience level is and where in the world have you operated.

Unless I have misunderstood your post, in which case, my apologies.

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Old 25th Jun 2009, 15:23
  #2304 (permalink)  
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To save a few of you, and us, the trouble of having to delete dozens more of these gullible posts you might like to watch this promotional clip.



If the penny has now dropped, and you are not busy providing details of your bank account to the supposed family of a deposed West African General, perhaps you could restrict comment to the subject of this thread.
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Old 25th Jun 2009, 15:48
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EASA Plans No Action On Pitot Tubes

Normally I don't post news or rumors preferring intstead to simply read what others think is important. But just to place a counterpoint alongside the rumor above about the Delta/NW A330 storm encounter

[quote]EASA Plans No Immediate Action On A330 Pitot Tubes

The European Aviation Safety Agency has decided, for now, to hold off on issuing an air worthiness directive concerning Thales-made pitot tubes on A330/A340s.

EASA said, “We are not planning any action at this stage pending the investigation” into the crash of Air France Flight 447.

The pitot tubes have come under fire in the wake of the crash of AF447 because the mishap aircraft, an A330-200, broadcast maintenance messages just before all contact was lost indicating inconsistent speed information and potential problems with the pitot tube. Air France and other airlines had previously encountered problems with the pitot tubes and Thales had developed an upgrade, but an equipment change was not mandated by safety officials.

Even before the crash, Air France had decided to upgrade its pitot tubes, but the mishap aircraft was still flying with the old standard. The airline has since upgraded all the probes, in part under pressure from its pilots.


Air France and aviation safety officials insist there is no data available at this point to suggest a problem with the pitot tubes was in fact linked to the crash. Industry officials point out that even with pitot tubes malfunctioning, pilots should still be able to fly the aircraft.

Aviation Week's AviationWeek.com.

Last edited by lomapaseo; 25th Jun 2009 at 19:05.
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Old 25th Jun 2009, 15:58
  #2306 (permalink)  
 
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Why does the EASA drag it's feet?

Apparently all the Pilots of Air France disagree with them!


Last edited by Razoray; 25th Jun 2009 at 16:54.
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Old 25th Jun 2009, 16:14
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wileydog3 post

Everything returned to normal except for the computer logic controlling the plane. (We were in alternate law for the rest of the flight.)
Is this really acceptable to you professionals?
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Old 25th Jun 2009, 17:54
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Odd thing is there is NOTHING on the FAA incident site or the service difficulty reporting site. Nothing on the sharing site. Nothing anywhere. ???
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Old 25th Jun 2009, 18:00
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Is this really acceptable to you professionals?
...that the report is being floated or that the rest of the flight was in ALTERNATE LAW? Not clear.

My point is just to find out if this is valid and if so, why, two days after the incident, is it completely invisible as far as the governing agencies websites? Or anywhere else for that matter.

Remember too this is yet another incident in the Pacific with unusual precip. We had other incidents with flame outs due to super-cooled water droplets (large and small) and this one mentions RAIN at cruise altitude (FL380?).
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Old 25th Jun 2009, 18:09
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Wileydog3;

It has also shown up on AvCanada as a forwarded email, also without any markers to prove credibility. Google shows nothing about the captain and no other reporting site has yet has verified. Seems strange to post the airline name and yet no other verifiable information.

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Old 25th Jun 2009, 18:09
  #2311 (permalink)  
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The unofficial Delta crew report must be verified. Nothing can move forward without this first step.
If the incident happened, one hopes that Delta does a FOQA program on the 330; if so, perhaps the QAR can be downloaded, (far more data and greater sampling rates for some parameters). One hopes too that given the incident and current circumstances they have already pulled the recorders including the CVR at NRT and shipped them to Washington.

Hopefully more information will be available on this throughout the day, with the usual caution that hindsight is 20/20. We know where this "points" but that is all we know as to possible cause(s).

augustusjeremy;
egg and chicken
a) 341115 - PROBE-PITOT 1+2/2+3/1+3
279334 - FCPC2(2CE2)/WRG: ADIRU1 BUS ADR1-2 TO FCPC2

OR

B) 279334 - FCPC2(2CE2)/WRG: ADIRU1 BUS ADR1-2 TO FCPC2
341115 - PROBE-PITOT 1+2/2+3/1+3

?????
These are recorded early in the entire sequence, (0210Z). The latter fault have associated Maintenance Status messages (ATA279000)

As per a number of experts' comments, the timing of the ACARS messages apparently can't be fully sorted out with 100% confidence not only because of the way the ACARS interfaces with the CMC, (Central Maintenance Computer) but becauses of the timings of individual system BITE processes which may complete and where such exists, latch a fault and then report. I personally think it is significant that the Pitot probes fault message comes before the first ADIRU messages but have nothing to substantiate that opinion. Perhaps those with special systems knowledge will be able to sort out which message came first by knowing that another fault wouldnt' have occurred without the first fault, etc etc.

A quick examination of the new ACARS PFR (Primary Fault Report?) list shows a few new details which had not been available on the first list made available:

A windshear Detect Fault, (My AMM shows “22-62-020” as the W/S DET FAULT)
The ISIS “Speed or Mach function”
Reference to ATA 279334 – FCPC2 and the explanation: WRG:ADIRU1 BUS ADR1-2 to FCPC2 – does this mean that FCPC2 took over inputs to ADR1 & 2?
Confirmation of Hard fault ATA 341115 PROBE PITOT 1+2 / 2+3 / 1+3
Clarification of the warning flag on the Capt PFD – Flight Director flag
Clarification of the warning flag on the F/O PFD – Speed Limit
Clarification of the PFD Flags at 0211 as “FPV”, flight path vector warning flags – this is an interesting fault
The “INTM” (Intermittent) AFS Class 1 Fault ATA 228334 – FMGEC1 (1CA1) BITE Detection is “CPC receives no data from FMGEC1”
My sole point in asking this is, if a rapidly devolving FMGES (Flight Management Guidance and Envelope System - all input devices, associated computers and crew interface units) are sending BITE results, by what method are they sorted for input into the CMC (and then sent to the ACARS)?
Perhaps the question is unimportant but the intent is clear enough; I just don't know enough to judge whether the order of ACARS messages we see is a result of this kind of critical process or not.
PJ2
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Old 25th Jun 2009, 18:18
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Wileydog3:

Usually JACDEC is pretty good in keeping up with even minor in-flight incidents; current recent events, which don't mention this event (?yet?), can be viewed here: JACDEC - Current News

(If someone is inclined actuarial-wise and bored, i'd love to know whether there are more 330 incidents reported recently or that i'm just more sensitive to the aircraft).
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Old 25th Jun 2009, 19:03
  #2313 (permalink)  
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augustusjeremy;

Yes, I think the TSM would help. Again, hopefully investigators are now far ahead of anyone here in terms of thinking/assessing/postulating/investigating. I'm sure in a few cases this site has provided some insight for the process but this is what they do and there are people who know the nuts-and-bolts of the 330 far better.

Re,
switched cables
Not sure what you mean by this but if you are referring to reversed cannon plugs for warning systems, yes, I know that has occurred, although I don't know where - manufacturing or regular heavy maintenance. It is not appropriate to provide details here but it would have resulted in an emergency if I'd followed the ECAM without thinking first.
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Old 25th Jun 2009, 19:18
  #2314 (permalink)  
 
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ACLS65 Quote
Per the A330 FCOM Flight Controls Description:

"Rudder and pedal deflection is limited as a function of the speed. Each limiter channel is controlled and monitored by its associated SEC. In case of double SEC failure, the max rudder deflection remains at the value reached before failure ; then, a max deflection is available when the slats are extended."

Apologies if this is silly - haven't seen it before and can't find an answer -
What would allowable rudder deflection be if, before the double failures, airspeed was 'indicated' to be very low. Would that allow full rudder following the SEC failures? Or is there logic that only allows min deflection once limiting is activated, until slats deployment?

Cheers
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Old 25th Jun 2009, 19:22
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I had a doc that mentioned that there were software differences between the A330 and A340, I will find that again.

In looking I found this doc that is so far the most in depth discussion of Flight Control Systems I have run across. This doc discusses FCS from the beginning through today including the Airbus and Boeing systems.

http://media.wiley.com/product_data/...0470059966.pdf
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Old 25th Jun 2009, 19:38
  #2316 (permalink)  
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This thread is about AF447
- It is not about CBs.
- Even non fliers know that flying into CBs is dangerous.
Well since the major, dynamic threat to safety along AF447's route of flight that night was a large area of CBs, and that was also the area which the aircraft was transitioning through at FL350 when was lost, I'd say CBs, what they produce in terms of threatening a flight (turbulence, icing, hail, vertical gusts, effects on aerodynamics and equipement), and difficulties detecting what can be the more severe aspects of them with airborne radar at high altitude, is indeed pertinent as any other discussion about it. Cetainly as pertinent as bits of debris, schematic drawings, and ocean currents.
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Old 25th Jun 2009, 19:52
  #2317 (permalink)  
 
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reallynoidea:
What would allowable rudder deflection be if, before the double failures, airspeed was 'indicated' to be very low. Would that allow full rudder following the SEC failures? Or is there logic that only allows min deflection once limiting is activated, until slats deployment?
I don't have detailed enough information to answer this, but it is an idea that has been floated here. I (and probably others) also brought up the idea of working through things from the probes to the ACARS msgs vs. starting at the ACARS msgs and trying to work back to what could have caused them.

My question at that point was if you could reach out and slap a piece of tape over the pitot tubes what affect would this have on the instruments in terms of IAS, AOA, ALT, and any other inputs to the ADIRU's, and then how would the FCS react.

The bigger question being how the FCS system would handle what may have appeared to be a rather sudden change in these parameters. There are various protections for different conditions that could come into play if the FCS was convinced that condition existed. On top of that you have the possibility the faulty inputs cause the FCS to fail what could be good components.

Previous A330 (and possibly since) upsets tend to make this seem like a recoverable situation, but add the weather, darkness, and any other number of factors on top of this and you might have a situation that is simply to complex to handle in the available time.
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Old 25th Jun 2009, 20:36
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Which type of pitots do NW A330's have?
And if it's Thales, are they being upgraded?
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Old 25th Jun 2009, 20:38
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Unverified

Has anyone else come across this post? Its reportedly a Delta (NW) A330.
Does anyone know about its validity?
Given the similarity apparently to AF447 this should be all over the news, but after searching everywhere, at least what I could in 2 hours, there is nothing to verify this - just a huge empty hole. Right now it looks suspicious. Very.

- GY
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Old 25th Jun 2009, 20:52
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Man v Machine Interface

One particular design flaw, I feel, on the Airbus series of aircraft is the fact that the throttles remain in a fixed position during flight. Your only reference for current power is the Engine/Warning Display and FMA. I have been in turbulence in an A320 where it was IMPOSSIBLE to read any of the screens in front of me...
The drill for unreliable speed is to fly pitch and power...difficult if you cannot read the instruments in front of you! With Airbus, currently you retard the throttles to their current power setting as displayed on the E/WD display. If we had throttles that moved, the first stab at a power setting would be the current one ie just disconnect the autothrust.
It would also make monitoring the aircraft a little easier- if you saw the throttles retard to idle in flight and yet you remained level, you would know (in steady state conditions at least) that if you let the situation develop you would likely encounter a stall. Similarly the reverse is true if you see the throttles move to MCT.
Perhaps it is time we, as pilots, are given back some of the intuitive information we require when HAL gives up the ghost.
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