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AF 447 Search to resume

Old 14th May 2010, 20:48
  #1041 (permalink)  
 
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grizzled;
Because the contemplation of other scenarios requires a great deal of coincidence. It is possible that a more complex , and statistically far less probable, chain of events could give the same result.

Hence your Occam's Razor approach is valid.

Just because there are 7 bodies not included in your example, changes nothing, as there will be valid other scenarios that developed following the impact the excluded them from the example.

Machinbird has also developed similar theories based on probabilities and his own forensic experience that fit nicely with the Occam approach - in my opinion.

mm43
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Old 14th May 2010, 21:41
  #1042 (permalink)  
 
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Given:
1. The BEA reported that (at least) 43 of the 50 bodies recovered displayed very similar serious compression injuries/fractures.
2. Those bodies were of passengers widely dispersed throughout the aircraft (according to seat assignments).
3. The simplest (reasonable) explanation for facts 1 and 2 is that all sections of the aircraft impacted in the same fashion. Why? Because the contemplation of other scenarios requires a great deal of coincidence. It is possible that a more complex , and statistically far less probable, chain of events could give the same result. BUT it’s not nearly as likely. For the vast majority of bodies from all parts of the aircraft to exhibit the same injury patterns, the simplest and most likely explanation is that those passengers all exhibited very similar injuries because passengers from all parts of the aircraft were subject to the same impact dynamics.
4. The simplest (reasonable) explanation for statement 3 is that the aircraft was intact on impact.
5. Therefore, it is more likely the aircraft did not break up prior to impact.
Now you've made me wonder how just those bodies found (and maybe many more) exited the fuselage... if it didn't break up?
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Old 14th May 2010, 22:33
  #1043 (permalink)  
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Occam would not have allowed himself to see only partitioned forensic evidence, excluding other injuries, completely neglecting the seven whose injuries challenge a rigid and blinkered conclusion of "seated at impact."

An easy and uncomplicated result cannot so qualify when incomplete work is done, or results are left out.

Unwinding this all too easy explanation backward from its conclusion takes one to some challenges that aren't explained. Only that evidence that supports a prior theory is included here. Occam's no fool, and easy doesn't add up to simple all the time.

The onset of upset and the unknown path downward may have produced evidence in the bodies of other things. Eventrated lung tissue, amputations not indicative of a seated posture, even a fully crepitus corpse, the "rag doll" effect. The injuries described in the second report relative to "proving" a seated person, could easily have been incurred while standing, or running. Soft tissue damage is left out; the lap belt can scythe through the musculature in the legs, down to the bone, frequently causing a fracture, the 'marionette' injury.

Another mystery. If the 43 were seated and belted, how did the rescuers discover them without the seat?

Last edited by bearfoil; 14th May 2010 at 23:32.
 
Old 14th May 2010, 22:53
  #1044 (permalink)  
 
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bearfoil;

That's why we need the DFDR/CVR to find out what the a/c actually did.

When Occam's rule is run over the outcome, none of what any of us have postulated may fit. For instance, all those that were found may have been unseated and standing, kneeling or in some other position at each end of the cabin. Now that could certainly be possible if the a/c was rotating about its longitudinal center of gravity in the so-called "deep stall".

Just another angle on it.

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Old 14th May 2010, 23:16
  #1045 (permalink)  
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mm43

Quite right. Without putting too fine a point on this, the evidence that is discussed is only that which allows the "seated" theory. It is never correct to eliminate from a report exculpatory evidence. The halo around the reports emanates from conclusion first, correct evidence later.

At the very least, consider the Vertical Stabilizer. Mounted in the fuselage similarly to AA587, no lesson was learned about sequestered stress. Three hard points to support the V/S/Rudder when each of these two failed fins show that the Rudder is mounted in a way that spreads stress, keeping it attached while the Fin blows off. Vertical take up arm (only one) failed in the vertical; the seven attachments of the Rudder were undisturbed, and that in the Plane not addressed by the axis' architecture.

As a last proposal, consider the damage done, the autopsies, the ACARS and try to prove the aircraft didn't impact inverted. No matter how hard the reports try to soften the culpability of the a/c, it should make little difference. The important events happened some time well before ACARS came alive. In other words, by the time ACARS reported the tip of the cascade, the A/C was lost.
 
Old 15th May 2010, 00:13
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[QUOTE][may have been unseated and standing, kneeling or in some other position at each end of the cabin. /QUOTE]

Lets go back to basics. When is the last time you penetrated a line of thunderstorms, and did not at minimum provide flight service with the heads up, ding ding, seat belts sign illuminated, or command Flight Attendants be seated. Now, given that the flight attendant stations at L1 were found and recovered indicating unoccupied, and that all pax would not be seated and belted, and that FA were not seated at assigned stations seems strange. This leads me to believe that what occured at altitude happen suddendly and with out cockpit warning to the cabin. Anyone in the back would have to quickly find seat refuge in any available seat, or would have been left with no seat and at the mercy of the aircraft movement. Not easy to climb down from the ceiling and into a seat. I think that what ever happened, that where ever you were in the airplane, is where you remained until the airplane contacted the water.
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Old 15th May 2010, 00:27
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Thanks for the info, mm43, and for your fantastic updates!

I guess it's pretty likely then, that they won't miss the wreckage when they finally pass by it.
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Old 15th May 2010, 00:52
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originally posted by wes_wall ...
When is the last time you penetrated a line of thunderstorms, and did not at minimum provide flight service with the heads up, ding ding, seat belts sign illuminated, or command Flight Attendants be seated.
You've hit it on the head! I honestly don't believe these guys knew what they were about to run in to. Why, and why not are really the questions.

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Old 15th May 2010, 03:16
  #1049 (permalink)  
 
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Quote HarryMann,
"Now you've made me wonder how just those bodies found (and maybe many more) exited the fuselage... if it didn't break up?"
Just a personal opinion, but one that fits with the debris found and other apparent circumstances as published by BEA, the fuselage must have broken on impact, probably both in front of and behind the wing. The exact pattern of breakup would depend upon pitch attitude, whether slightly nose down or slightly nose up.
Even if perfectly flat, the wing should help decelerate the area above the wing more rapidly than those areas just behind and just ahead of the wing. (Talking about the vertical component of deceleration) This would break the top of the fuselage in those stress areas. But to add another complication, if the aircraft were slightly nose up on touchdown, the bottom of the fuselage would fail in longitudinal tension behind the wing at touchdown, followed by the top of the fuselage in the same general area as the remainder of the fuselage impacted.
The large debris from the interior of the aircraft found floating guarantees that the fuselage was ruptured at some point in the impact sequence.
I would expect some fairly large chunks of aircraft and an extensive debris field primarily consisting of small parts and interior components. The impact energy does not appear to have been high enough to thoroughly fragment the aircraft, but it was certainly sufficient to break the fuselage.
Again, just a personal opinion. Perhaps we will see a scan of the real thing in the not too distant future.
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Old 15th May 2010, 06:35
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HarryMann,

Machinbird answered your question for me.

I didn't say (or mean to imply) that the aircraft didn't break-up (as it obviously did at some point). But I believe (on current available info, which is still very sketchy and full of unknowns) that it's more likely that it broke up on impact with the ocean, rather than at some point prior to impact.

The pathology mentioned by the BEA is just one reason I tend to support that scenario as more likely, at this point. The damage patterns and sizes of some of the recovered pieces we have seen of the aircraft, along with the sequence and content of the ACARS, lend more credence (IMHO)to a substantially intact aircraft impacting the ocean, than to a scenario of inflight break up and the subsequent descent of various parts that were no longer connected.

Of course I may be wrong, which is why I choose my words carefully in describing likelihoods and possibilities. Regardless, the all important questions of "what happened and why?" won't be answered without the aircraft being located and (please God) the recorders.

grizz

Last edited by grizzled; 15th May 2010 at 06:53.
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Old 15th May 2010, 12:50
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Post 1038 and Ark Royal

mm43,
I have been following this thread with interest, thank you for your efforts, but I was startled to see the image from the C&C Hugin Survey. I directed the search for the Ark Royal . The wreck was originaly located by a surface mounted multibeam on another vessel, Odin Finder, and then confirmed by the survey from C&C's AUV on Rig Supporter. It was of course in much shallower water than the AF447, just over 1,000 meters. From what I know the basic equipment of the REMUS AUV's being used now is more or less the same as the HUGIN 3000 we used then, but of course with eight years improvement in signal processing. It might be interesting to see how the returns were rendered in Fledermause. The image you reproduced was combined from a variety of passes over the wreck at different altitudes and headings. Subsequently we captured video of the Swordfish and deck lift. What you can see is the underside rib bracings.
I notice that many posters are discussing the question of whether the debris will be widely dispersed or not. The Ark Royal was around 700 feet long, and weighed about 23000 tons, and was sunk because of one torpedo hit in the hull. She capsized before sinking, and obviously broke up on the surface because we found the wreck in two pieces, with a large amount of debris from the flight deck and Island, and a field of Fulmar aircraft from the hangar deck. The main part of the wreck was seperated from the bow section by around 800 metres, and I have always thought that this was quite a puzzling distance bearing in mind that the two pieces only had 1025 metres to descend from surface to sea bed. Its my own view that given the impact on the sea, and the depth of over 4000 metres to sea bed, debris from AF447 will be spread over quite a wide area.
Thanks again for your patient work mm43.
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Old 15th May 2010, 16:52
  #1052 (permalink)  
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mm43;
I honestly don't believe these guys knew what they were about to run in to.
That would go to the use of and reading/interpretation of the signal of, radar. The radar was always on during the two to four hours it takes to transition the zone/weather so as to anticipate and pick one's path. Even then it got very rough sometimes. The use of radar was discussed in the first AF447 thread. Unless there was some very rare phenomena, (mesoscale event?, as described in earlier posts), these transitions, while never 'routine', are not full of surprises either - this is what makes the accident such an enigma! Wes Wall is entirely correct; the sign is on, the FA's are fully briefed well ahead of time, (most are familiar with the routine). That the F/A seats found, if I recall correctly from the report, were assessed as "not occupied" then, is perhaps evidence for "surprise", but we do not know the reasons why or what. PJ
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Old 15th May 2010, 17:34
  #1053 (permalink)  
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PJ2

My understanding of mm43 re: "surprise" is as a general comment, and not related to weather, necessarily. My belief is that A/P trip out was a "surprise", whether due to unreliable data (A/S) or a sudden onset of turbulence, that exceeded the A/P's programmed parameters. Any turbulence producing reactions in A/P of beyond 45degree roll had to have been sudden, or pilot would have started manual flight prior, no? The cascade of bad news seems like a sim ride nightmare, presenting warnings that could be solved only by reference, and Alternate Law II removed protections that cannot be regained until landing, so the pilot was thinking of a very long flight in either direction, should he even be successful at maintaining safe level flight. I cannot envision any other response than that of surprise. imo

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Old 15th May 2010, 19:39
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Post 1038 and Ark Royal

swordfish41,
Thanks for your response. I had seen the BBC documentary on finding the Ark Royal, and knowing that multibeam sonar had been used in the search, did a Google search and came up with the original. As the deck/hangar lift wasn't identified, I did a little research and found its dimensions, which then compared well with the dimensions I found for the Swordfish MKII.

Search techniques have probably changed a little over the years, and even though the physical constraints are the same, the technology developed to overcome the problems has advanced.

Your swordfish41 handle is appropriate!

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Old 15th May 2010, 19:52
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Update: "Seabed Worker" - position

The following graphic shows the latest available positions for the vessel. My interpretation is that the "Seabed Worker" has been tending her 2 AUV's, or placing/recovering bottom positioning beacons.

15 May 2010 06:19z Hdg 190.4 Spd 01.1 3°06'12"N 31°03'42"W
14 May 2010 21:25z Hdg 235.0 Spd 01.9 3°03'15"N 30°57'34"W
14 May 2010 19:40z Hdg 078.3 Spd 02.7 3°04'56"N 30°55'10"W
14 May 2010 09:11z Hdg 064.2 Spd 01.9 3°05'00"N 31°07'22"W
14 May 2010 07:30z Hdg 294.7 Spd 01.0 3°05'01"N 31°07'18"W



mm43

Last edited by mm43; 15th May 2010 at 21:24. Reason: error in graphic
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Old 15th May 2010, 20:46
  #1056 (permalink)  
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bearfoil;
whether due to unreliable data (A/S) or a sudden onset of turbulence, that exceeded the A/P's programmed parameters
Both are possible, and I tend to agree, vice 'not using radar, or otherwise not avoiding the obvious'. I also concur with your assessment that by the time the ACARS messages were 'in process', (to use Airbus terminology) the safety of the flight was already compromised. I take as evidence for this the rapidity with which events unfolded, (essentially, 4 to 6 minutes), and the potential for crews to respond effectively (meaning, to stabilize a rapidly unfolding series of events). I have seen and know the surprise effects upon crew members of such (inadvertent) bank angles and subsequent a/p disconnects; it is not pretty and can indeed result in disorientation.

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Old 15th May 2010, 21:16
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PJ2, Bearfoil, Wes_Wall;

"Surprise" - was certainly the end result. As PJ2 knows, I had previously made reference in the old AF447 thread to what I surmised may have been an insidious fault with the radar. By that I mean one that the inbuilt self-diagnosis fault system had failed to detect.

"Surprise" - because the flight was obviously proceeding normally and there was no marked change in GS over the last half hour before 0210z. So, I have assumed that if there was any turbulence experienced, it was of the light chop variety.

"Surprise" - because if none of the above turns out to be true, then what was happening?

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Old 15th May 2010, 21:39
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mm43;
then what was happening
I don't want to re-hash old arguments regarding impact but I have no reason to doubt the conclusions of the BEA interim reports. However, the aircraft somehow had to lose about 70 to 80kts of forward speed and associated energy/inertia to approach the actual ('g') stall speed. That is not easy to do nor force to happen. If this is the case then a stall must be reconciled with the difficulty in "achieving" same - in normal air it is just very difficult to stall the airplane even in Alternate Law, (I or II). Entry into a thunderstorm however, removes all such theories/notions. The question, as we all know is, did an intact airplane strike the surface of the sea or was the fuselage compromised. We each have our thoughts and reasons for same.
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Old 15th May 2010, 22:00
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At the very least, consider the Vertical Stabilizer. Mounted in the fuselage similarly to AA587, no lesson was learned about sequestered stress. Three hard points to support the V/S/Rudder when each of these two failed fins show that the Rudder is mounted in a way that spreads stress, keeping it attached while the Fin blows off. Vertical take up arm (only one) failed in the vertical; the seven attachments of the Rudder were undisturbed, and that in the Plane not addressed by the axis' architecture.
Bearfoil,
Having read this Thread and the previous one, you have postulated this Idea multiple times. Still it seems to contradict all findings. (Please take some time and carefully check the pictures of damage and the direction of buckling of the attached aluminum structures or the ribs of the VS in the second BEA report).
Why do you insist so much on this theory? Despite the fact that there is not the slightest evidence that would support it ?
And please don't refer to the apparently visually intact vertical stabilizer, that thing ALWAYS remains almost intact (check the ones of Perpignan or now even Afriqiah).
Andf even if it would have sheared of at altitude this would surely have been a secondary effect of overstress (No these things are not meant to survive 9g manouvers) to a preceeding loss of control. And which part fails first in an overstress -be it a wing or horizintal or vertical stabilizer- doesn't make much of a difference....
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Old 15th May 2010, 22:04
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Hi,

For add to the all sudden of the event ...
None of the bodies was with lifejacket .. and lifejacket (s) found were in their pouch (if remember well)
How this is possible than in a 4 or like minutes nobody try to done lifejacket?
How they were incapacited ?
Or .. nobody knows the plane was fallen ?
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