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Old 10th Jun 2009, 00:02
  #961 (permalink)  
 
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PJ2

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

??

Last edited by Will Fraser; 10th Jun 2009 at 00:16.
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Old 10th Jun 2009, 00:03
  #962 (permalink)  
 
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PJ2,

an examination of this area either by drawings or physical inspection of other 330's may tell us what else "left" with the VS, pulled by piping/cabling/wiring/ancilliary structure etc - pure conjecture but at least "reading" the trace.
Agreed. It would be a reasonable assumption that disruption of the airframe at this scale and location would have some impact on the structure of the THS also. In fact, could those white box structures be directly connected to the spar structure of the THS. Any A330/340 mechanics care to offer an opinion? PJ2, you appear to have access to the A330 AMM, is there any info in there?
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Old 10th Jun 2009, 00:18
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Força Aérea Brasileira is reporting a max distance of 85km between retrieved bodies. 46km radius (92km max distance) for 'large piece' debris.

I'm no expert in ocean currents...but that seems pretty far apart for an intact water entry..
Many thanks for that... tend to agree, but noe expert either.

The missing information is where in that circle the fin (VS) was found!
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Old 10th Jun 2009, 00:24
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DorianB, the number of bodies recovered is now reported as 41. As bodies are identified, they will be matched to seat assignments, and the coordinates where they were recovered.

If clusters of bodies are found up to 85 km apart, that would seem to be a greater distance than what might be expected from an intact aircraft crashing into the sea.
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Old 10th Jun 2009, 00:26
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Pitot tubes

Returning to the subject of pitot tubes.
The manufacturers, I believe in this case Thales, will probably be following a pattern that has been used successfully for years.
One must then ask, why are the A330/340 subject to contamination, if that’s the right word. Could it be their location ? i.e. high/low pressure in the wrong place preventing the drain from functioning correctly.
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Old 10th Jun 2009, 00:32
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Originally Posted by scarebus03 View Post
But why did the following IB aircraft divert 56kms to avoid the same storm?

Don't shoot the messenger, it's from the Spanish press three days ago,
How do you know that AF447 did not divert the same 56kms?

Please explain how you, or anyone else would know this......
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Old 10th Jun 2009, 00:36
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Fairly certain I see three attach/systems. the forward hole (missing the pin) is 'shading' a bulkhead cap similar to the most aft structure. All three towers seem present, though what would be the port side of the forward carriage is in darkness. The fairing at the emp/VS mate is gone, uncovering the primer in the shape of the fillet. (That may help some locate the assembly in the above picture of the a/c)

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

I'm beginning to think the vertical didn't separate in flight. If it did, it was part of a package, including the empennage. Experience with AA587 would make us jump to that conclusion, (guilty as charged in the beginning), but there are too many dissimilarities, e.g., failure characteristic, intact rudder.
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Old 10th Jun 2009, 00:37
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Originally Posted by Backoffice View Post
Returning to the subject of pitot tubes.
The manufacturers, I believe in this case Thales, will probably be following a pattern that has been used successfully for years.
One must then ask, why are the A330/340 subject to contamination, if that’s the right word. Could it be their location ? i.e. high/low pressure in the wrong place preventing the drain from functioning correctly.
There's nothing particularly special about pitot probes icing up - if thats what happened. They all can be iced up, and are all heated accordingly. So any extreme weather conditions outside the qualification of the probes could ice up ANY probe design.

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

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

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

Without looking into the SB about these probes in detail one cannot say whether the specific issue that its supposed to correct is a likely, unlikely, or negligible factor in any possible probe problems. it's suspicious that an aircraft with possibly suspect probes had a problem which might relate to the probes. But I'd be loathe to make the direct link. After all, if it were a serious deficiency then I'd have expected stronger action by Sb and/or AD AND many more issues in service.
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Old 10th Jun 2009, 00:43
  #969 (permalink)  
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Will Fraser;
Fairly certain I see three attach/systems. the forward hole (missing the pin) is 'shading' a bulkhead cap similar to the most aft structure. All three towers seem present, though what would be the port side of the forward carriage is in darkness.
'k, I can take a further look by bringing the shadows up a bit, thanks. We'll know soon enough I'm sure.

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

I strongly suspect the boxes are near or perhaps part of the THS structure but can't say so.
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Old 10th Jun 2009, 00:44
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85km over several days

SaturnV @1000,

It's theoretically possible that two piles of objects separated by only a few hundred meters could be in diverging current streams (especially as the North and South equatorial currents meet and diverge in that area of the Atlantic). 85 km over several days is less than 1 km/h relative difference velocity.
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Old 10th Jun 2009, 00:53
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PJ2,

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

ClippedCub, others.

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



Can you elaborate? Sorry if I'm missing the obvious!
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Old 10th Jun 2009, 00:53
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Pitot tubes

Thanks BigHitDH and Mad Scientist.
My doubts were raised by the comments that the replacement tubes may not completely cure the problem, implying (to me) that Airbus might be aware of another issue, purely conjecture on my part.
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Old 10th Jun 2009, 01:00
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ttcse;
Don't forget the vertical possibility, say from impact while in a spin or stall.
With respect, transport category aircraft do not "spin". Cubs, 172s and light twins "spin". The NTSB animation of the Colgan accident is as close to "spin" as an airliner might get - more like a spiral dive quickly achieving very high speed with high nose-down pitch attitudes and requiring significant altitude to recover, if at all.

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

Any high-speed impact with water is the same as hitting a rock face thus the exhibited wreckage distribution pattern and disintegration would be like SW111 if anyone is familiar with that investigation, (I am, but only very much on the periphery). With the greatest of respect for the victims and families and apologies for a terribly indelicate observation, the condition of the remains found thus far almost certainly indicates an in-flight breakup at some point during the accident sequence.
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Old 10th Jun 2009, 01:07
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Thanks for the new perspective BigHitDH, your photo indicates a lack of forward attachedstructure, which is helpful. Go back a couple of pages for PJ2's photo I was describing. Don't think that forward 'hole' is a hole in PJ2's photo. Customary attachment is to line the holes up, as shown below in the A310 photo, (also shows relation of rear attachment to the horizontal, for the A310 anyway),



The missing rudder was due to a flutter, in the photo case, due to a fault in the rudder structure.
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Old 10th Jun 2009, 01:17
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egd, theoretically yes.

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

From the post-mortems (on Wiki), eight of the recovered bodies had been ejected from the aircraft before it crashed. Other causes of death (at least contributory) included explosive decompression (those sitting near windows), hypoxia, asphxia (one child and one infant), vertical force injury, and three who died by drowning.
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Old 10th Jun 2009, 01:27
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Hopefully they won't blame this on the pilot too.
Now don't be silly... The PIC of 587 overcontrolled and drove the yaw oscillation to a destructive degree - FACT

Not a good or useful contribution IMHO
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Old 10th Jun 2009, 01:28
  #977 (permalink)  
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ttcse;

Thanks - I had forgotten that photo - but we cannot see a damage pattern. PJ2
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Old 10th Jun 2009, 01:34
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eqd stated:

It's theoretically possible that two piles of objects separated by only a few hundred meters could be in diverging current streams (especially as the North and South equatorial currents meet and diverge in that area of the Atlantic). 85 km over several days is less than 1 km/h relative difference velocity.
This seems logical to me; it is a small difference in velocities given the times involved. Unless an expert weighs in with some knowledge of oceanic drift patterns, I would be cautious in reading too much into these distances. In addition to ocean currents, certain objects may be affected by surface winds as well. One would expect a difference in motion between objects which are partially above the water (and thus exposed to wind) versus objects that are more or less level with the surface.
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Old 10th Jun 2009, 01:43
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jmig29;
My experience tells me something very terrible happenned in cruise, that did not give the crew any reaction timing, which leads me to think maybe other "non spoken" aspects may have to be considered. Looks to me that the "ACARS automatic reports" were just the final part of the problem, when there was allready no hope left for those souls.
This has been what my experience has been saying to me all along (structural breakup due over-stressing during entry into a CB, ACARS messages recording the effects of subsquent failures, unrelated to cause), but there was simply not enough evidence to state it and so I remain uncommitted to any conclusions still. The Perpignan intact fin (we don't know what the same structure looks like however), keeps the question suspended somewhat.
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Old 10th Jun 2009, 01:48
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This has been what my experience has been saying to me all along
No doubt there are many who share the same thoughts, but there is nothing which has been discussed that offers any credible evidence to any onset of trouble. What ever happen occured prior to the first ACAR.
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