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AF447

Old 11th Jun 2009, 23:48
  #1201 (permalink)  
 
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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

Last edited by ClippedCub; 11th Jun 2009 at 23:59.
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Old 11th Jun 2009, 23:50
  #1202 (permalink)  
 
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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
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Old 12th Jun 2009, 00:02
  #1203 (permalink)  
 
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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.
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Old 12th Jun 2009, 00:03
  #1204 (permalink)  
 
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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'

Originally Posted by The Tale of the Comet - Derek Dempster
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 place
Admiited, 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!
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Old 12th Jun 2009, 00:03
  #1205 (permalink)  
 
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What would you do?

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?
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Old 12th Jun 2009, 00:05
  #1206 (permalink)  
 
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Harry, there is a difference between accelerating to terminal velocity and decelerating from 400 knots to Terminal velocity.
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Old 12th Jun 2009, 00:21
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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
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Old 12th Jun 2009, 00:26
  #1208 (permalink)  
 
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Postado por: marceloambrosio

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.
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Old 12th Jun 2009, 00:36
  #1209 (permalink)  
 
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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.
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Old 12th Jun 2009, 00:39
  #1210 (permalink)  
 
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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.
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Old 12th Jun 2009, 00:41
  #1211 (permalink)  
 
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@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...
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Old 12th Jun 2009, 00:52
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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.
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Old 12th Jun 2009, 00:59
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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 ?
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Old 12th Jun 2009, 01:22
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> 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.)
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Old 12th Jun 2009, 01:34
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Originally Posted by WhyIsThereAir View Post
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.
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Old 12th Jun 2009, 01:38
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> 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.
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Old 12th Jun 2009, 01:51
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Agree with Capt Fishy

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 shit 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
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Old 12th Jun 2009, 02:36
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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...
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Old 12th Jun 2009, 02:48
  #1219 (permalink)  
 
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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."
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Old 12th Jun 2009, 03:01
  #1220 (permalink)  
 
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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.
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