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AF447

Old 23rd Jun 2009, 02:03
  #2161 (permalink)  
 
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To be absolutely 100% safe, you'd have to say the aircraft broke up somewhere between 37,000 feet and the bottom of the ocean. I don't believe for a minute it landed intact and broke up as it sank, but I'm not sure we can conclusively rule it out (anyway, ships often break up on the way to the bottom).

I suspect the recovered debris contain the information needed to determine where the break up occurred. But the pictures of the debris may not.
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Old 23rd Jun 2009, 03:06
  #2162 (permalink)  
 
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Debris Distribution

Without trying to make any assumptions, I found some of the earlier maps relying on FAB PowerPoint presentations overlaid with BEA debris data points to be rather ambiguous.

Many of the FAB graphics appear to be designed for media consumption and minor? details such as the "Ultimo Reporte" position do not appear in the correct positions.

I know 'rer47' mentioned some pages back the link to:- Final Route of AF447 - an Analysis and the map associated with it, along with some assumptions made could be worthy of consideration.

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Old 23rd Jun 2009, 03:12
  #2163 (permalink)  
 
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[B]Aircraft could have made a ditch or broken up in it's decend to the surface at some point.To my knowledge impossible to prove any of this scenarios just now. Both of them would almost give the same results in form of found debris at this point, or am I wrong ?
Regards
1011

wings1011
For sure from just looking at the pictures and reading the news 'we' can't prove anything. That's up to the investigators.

However we do have inferences.

For one thig it has been reported that the investigators believe the aircraft broke up based on wreckage distribution and body and seat recovery.

Some of us read the recovered wreckage photos as mostly free fall damage (terminal velocities in a vertical direction). Some of which seems to have fallen out of the fuselage at altitude while other pieces were ejected from the fuselage sections when they free fell into the water.

Much of the conclusive stuff has sunk so here we are working with flotsam and jetsam. No harm in waiting for more conclusive evidence but meanwhile some of us are beginning to focus on fewer postulations based on our beliefs.
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Old 23rd Jun 2009, 03:14
  #2164 (permalink)  
 
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If there was a controlled ditching gone wrong, why would they ditch. We determined that they didn't encounter significant hail, but even hail taking out the engines would be a stretch. Like others, I'm leaning towards in-flight break-up from overload, spinning, etc, but there's nothing conclusively pointing that way, unless we can rule out a ditching.

Can anyone with more probe knowledge comment on what readings in terms of AS, AOA, and ALT we would expect to see with an ice clogged pitot?
AOA is a separate probe or vane, don't think it uses static, Alt runs off static. AS is pitot and static.

Thought cabin pressure readings could be corrupted by static.

Can't remember the air data system schematic PJ2 posted, but the statics should be cross plumbed between left and right fuselage sides to neutralize effects of side slip and yaw rate, so they wouldn't be effected by yaw due to an engine out transient for example. Though something as severe as a spin probably would impact the static readings.
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Old 23rd Jun 2009, 03:22
  #2165 (permalink)  
 
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takata, what if you flipped your analysis, so that the hypothesized impact points were west of 30W, and not east of it?

The Brazilian Air Force search grid for June 1 is limited to the projected track. On June 2, the Air Force does two rectangular grid searches that run eastward from the search grid of June 1. Searches on June 3 and 4 are in areas prediominately east of the track. To me that suggests that the June1-4 surface current was similar in velocity and direction (SW to NE) to what is shown in the chart for June 5, and the Air Force search pattern was based on the expected drift from the current.

If AF447 had turned west to divert around the CB complex, or even turned back toward Brazil when systems began to fail, and began breaking up around 31 or 32W, then the prevailing surface current may have carried parts of the wreckage NE to the point near 30W and 3N where the first bodies and confirmed parts of the plane were retrieved.

If the above hypothesis is correct, then I would expect that the first group of bodies that were recovered to be associated with the plane's impact with the water, and the second larger group of bodies which was subsequently found much further north to possibly have left the plane during the initial break-up phase. (There are enough bodies that the investigators should be able to match bodies with assigned seats and test the validity of the above hypothesis.) This clustering of the bodies generally into two distinct groups would be the reverse of what one might expect if the plane had remained on a NNE heading, and broken up.
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Old 23rd Jun 2009, 03:50
  #2166 (permalink)  
 
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An interesting paper, The Evolution of Flight Data Analysis by Neil Campbell.

http://asasi.org/papers/2007/The_Evo...l_Campbell.pdf
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Old 23rd Jun 2009, 05:35
  #2167 (permalink)  
 
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Re: debate on whether the aircraft may have been mostly intact until it reached the water (e.g., a low-speed controlled ditching, or "flat" spin).

Given estimated fuel aboard, and implied assumption that structural integrity was maintained until impact but almost certainly not beyond, what is the likelihood of a post-impact fire in that circumstance?

If the probability is high, then does the (reported) absence of charring on recovered debris or bodies tend to exclude a controlled ditching or similar hypothesis, and suggest structural integrity was lost prior to impact with the water? Or would debris and bodies initally sink (and have been protected from any fire), surfacing only later?
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Old 23rd Jun 2009, 05:47
  #2168 (permalink)  
nyt
 
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CVR/FDR pinger heard:
Les boîtes noires de l'Airbus Rio-Paris repérées - Société - Le Monde.fr
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Old 23rd Jun 2009, 05:48
  #2169 (permalink)  
 
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French newspaper "Le Monde" says black boxes located

As "Le Monde" is generally regarded as the most reliable french newspaper, I thought I'd quote it here :

Les boîtes noires de l'Airbus Rio-Paris repérées - Société - Le Monde.fr

Quick and dirty translation : the "Nautile" submarine has beed diving on June 22nd in an attempt to locate the black boxes of the Air France Airbus that vanished on June 1st over the southern Atlantic. It was guided by a very faint signal picked up by one the the French Navy ships. Search is made very difficult due to very montainous nature of the seabed with depths around 5,000 meters. The batteries of the black boxes should last for another week or so.
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Old 23rd Jun 2009, 05:48
  #2170 (permalink)  
 
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Given estimated fuel aboard, and implied assumption that structural integrity was maintained until impact but almost certainly not beyond, what is the likelihood of a post-impact fire in that circumstance?
ironically, the more fuel in the tanks the less chance of a fire due to the limited presence of vapour.
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Old 23rd Jun 2009, 05:53
  #2171 (permalink)  
 
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Okay - heres a long shot and if its jumping to conclusions before the full report sorry.

Take off 7pm, three pilot crew one captain, two f.o,s probably Air France cadet system pilots.( nothing wrong with that but bet they probably have never been upside down in an aircraft let alone a big one hence the usual degradation in handling skills that modern aviation teaches)

Captain goes back shortly after take- off to first class or what ever rest they use, F/Os left in charge.

jet hits some cb's , maybe painting on radar, maybe not.

For one reason or another - all of which have been covered, jet reverts to alternate law, unreliable airspeed actions required ( memory items ) as A/P and A/T have disconnected.

Still in bumps, PF - who I would assume should be in the RHS... but maybe not....very low buffet margins @ F350. Speed tape dancing up and back.. maybe ...bearing in mind that depending on the sort of protection remaining any thing is possible with the pitch /bank/altitude/speed and thrust levers.

In attempt to control aircraft, jet is overhandled ( have seen it before with pilots "wanting to fix something'...

exacerbate situation and loose control. Jet breaks up at some point.

Jet aircraft in spiral dive or simliar, ROD works out to be about 12 000 FPM ( based on B707 loss of control over East Sale - hit water from 6000 feet in about 25 secs after demo of VMCG loss of control. yaw rate enough to shear off inboard engine and take out #4.

They managed to get a may day out ... just ..

So may have these guys but who was listening? , and besides with the yaw and pitch rates I'm not so sure you might have thought more about getting back on the rails first.

All speculation but how come AIRBUS have just put out a bulletin related to unreliable airspeed flight and its importance.

Yes granted may have been environmental initial cause but if I thought that lightening and thunderstorm penetration would result in this occurence being any greater than 1 x10-9 then I would not still be sitting in a cockpit?

Which I have done on both B707/777 and Airbus 320/343.345 types for 13000 hours.

I have ultimate confidence in the machinery - it is the human side that bothers me now with the increasing reliance on automation to make ones job easy ... right up to when it checks out and says handing over....!!

Not to speak ill of the dead but this is becoming all too common.

Ready for all incoming now... If I am wrong I will retract all of this conjecture.. just seems plausible to me...
W
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Old 23rd Jun 2009, 05:56
  #2172 (permalink)  
 
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@ NYT

Yup, it looks like that a weak pinger has been heard...

5000mts depth, at least is something! Hopefully the FDR/CVR can be recovered succesfully
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Old 23rd Jun 2009, 06:05
  #2173 (permalink)  
 
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woodja51

Did you bother to check the experience of the co-pilots?
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Old 23rd Jun 2009, 06:12
  #2174 (permalink)  
PJ2
 
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JD-EE;
...to satisfy the fussy folks.

It rather obviously broke up SOMEWHERE.
Indeed it did. Somewhere between 40,000ft and sea level. What I meant seems clear to most.

Anxiously awaiting further news regarding the reports of hearing pings and anything else, signalling large metal structures, or not. Are there any further photos of wreckage found or are we at an end, more or less?
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Old 23rd Jun 2009, 06:18
  #2175 (permalink)  
 
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Air France "black box" signals located
Tue Jun 23, 2009 2:06am EDT

PARIS (Reuters) - Signals from the flight data recorders of the Air France airliner that crashed into the Atlantic killing all 228 people on board have been located, Le Monde newspaper said on its website on Tuesday.

An Air France spokeswoman said she could not confirm the report.

Le Monde said French naval vessels had picked up a weak signal from the "black boxes" and that a mini submarine had been dispatched on Monday to try and find them on the bottom of the rugged ocean floor.

The "black boxes" may contain vital information that could help explain what happened when the Airbus A330 aircraft crashed into the sea en route from Rio de Janeiro to Paris on June 1.

(Writing by James Mackenzie, Editing by Ralph Gowling
Air France black box signals located: report | U.S. | Reuters
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Old 23rd Jun 2009, 06:22
  #2176 (permalink)  
 
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Take off 7pm, three pilot crew one captain, two f.o,s probably Air France cadet system pilots
Captain 11,000 hrs TT (1700 on Airbus A330/A340)
Copilot 3,000 hrs TT (800 on Airbus A330/A340)
Copilot 6,600 hrs TT (2600 on Airbus A330/A340)
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Old 23rd Jun 2009, 06:44
  #2177 (permalink)  
 
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Air France A330 Black Box

Article from: Reuters
SIGNALS from the flight data recorders of the Air France airliner that crashed into the Atlantic killing all 228 people on board have been located, Le Monde newspaper said on its website today.

An Air France spokeswoman said she could not confirm the report.

Le Monde said French naval vessels had picked up a weak signal from the "black boxes" and that a mini submarine had been dispatched yesterday to try and find them on the bottom of the rugged ocean floor.

The "black boxes" may contain vital information that could help explain what happened when the Airbus A330 aircraft crashed into the sea en route from Rio de Janeiro to Paris on June 1.
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Old 23rd Jun 2009, 06:50
  #2178 (permalink)  
 
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CNN reporting that the boxes have been found.
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Old 23rd Jun 2009, 06:51
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CNN reporting that a sub has been dispatched to the area after the "ELT's" from the recorder (s) have been heard...hope it's true...
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Old 23rd Jun 2009, 07:01
  #2180 (permalink)  
 
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Conjecture with a modicum of deja vu

Woodja51

As a long-haul heavy driver, I too have this notion. From experience, knowing the experience of the relief crew operating the airplane while I am "down the back", I "rest" very uneasily.

It is not about hours on type, it is about EXPERIENCE. Typically, a long-haul FO or SFO with about 5,000 hours, has, if all he/she has been flying is long-haul, about 10-15% of total time as experience. The other 85-90% is either sleeping "down the back", or watching the AP do the hard stuff.

The expression "clutched defeat from the jaws of victory" comes to mind (along with "if it ain't itchy, don't scratch it").

Time for the Kevlar flack jack.
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