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AF 447 Search to resume (part2)

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AF 447 Search to resume (part2)

Old 12th May 2011, 14:31
  #1221 (permalink)  
 
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I just wonder why the diagram has them labelled in blue? I wonder why they would bother lifting them as the fadec is mounted on the engine.
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Old 12th May 2011, 14:33
  #1222 (permalink)  
 
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Originally Posted by infrequentflyer789
It all makes sense if they recovered the pilots (in case they can get any medical evidence for investigation) but asked the court to rule on the pax + cabin crew bodies.
That crossed my mind too. Then it can be considered as established, that the captain was in neither of the two pilot seats when the crash happend ?
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Old 12th May 2011, 14:34
  #1223 (permalink)  
 
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Originally Posted by JD-EE
Indications seem to be the range should have been much greater than the 1700 meters that sticks in my memory.
I think I saw that figure in the Metron report. My estimate was 2-3km. I expect that Metron was intentionally conservative.

To answer your earlier question...

According to Urick, deep sea noise at 100Hz ranges from 60-80 db re 1uPa/sqrt-Hz, depending on sea-state and shipping activity. At 1kHz, the range is 45-70db, with decreased influence from shipping. At 10kHz it's down to 25-55db. At 100kHz: 25-35db, where the high side is still decreasing and the low side is rising due to thermal noise. The lowest of lows, not counting certain under-ice situations, is about 18db at 40kHz, sea-state 0, no shrimp or rain. The downward slope in those numbers is not constant, but has flatter and steeper areas, and is not even certain to be monotonically decreasing, due to the particular local sources of noise. Noise is understandably higher in shallow areas and enclosed bays by 5-15db over the max values above.
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Old 12th May 2011, 14:36
  #1224 (permalink)  
 
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800 VU is one of the avionics racks normally located below the flight deck floor.
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Old 12th May 2011, 14:37
  #1225 (permalink)  
bearfoil
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jcjeant

"I don't see how find the track of the plane if I know the altitude LKP and the time to impact and the
heading at impact ...

With these 3 data only .. the equation cannot be solved
There are many more unknowns"..............

************************************************************ ***
It has been a while, but you get the gold.

You have just described my frustration at the "conclusions" bright people have made re: this crash. Because of a subtle misuse of a common phrase, for two years smart guys have entertained the thought that AF447 always had control. They will tell you not so, but clearly, this "Heading at Impact" drivel is the result of BEA's use of "En Ligne de Vol". Words have meaning, and always be sceptical when reading prose by folks are get paid to write.

Salute mon cher ami

Bear
 
Old 12th May 2011, 14:37
  #1226 (permalink)  
 
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Originally Posted by tubby linton
I just wonder why the diagram has them labelled in blue? I wonder why they would bother lifting them as the fadec is mounted on the engine.
This was a slide used during the press conference. Colors may be related to the speach about parts. Sadly, it was not live broadcasted (I only saw few minutes). I heard that they were talking about recovering EPRs which, they hope, would have very important data to understand the crash. They also talk about the THS screw and most parts in red.

S~
Olivier
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Old 12th May 2011, 14:45
  #1227 (permalink)  
 
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The BBC's report from the press conference states that a report will not appear until early 2012 and also that it will be Monday at the earliest before any of the data is read from the fdr/cvr.They also mention that the pitot tubes(The jet's speed sensors) have not been found.
BBC News - Air France Rio crash: Report not expected before 2012
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Old 12th May 2011, 15:07
  #1228 (permalink)  
 
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Hi Bearfoil,
I missed you, hopefully here you are!
Originally Posted by Bearfool
Because of a subtle misuse of a common phrase, for two years smart guys have entertained the thought that AF447 always had control. They will tell you not so, but clearly, this "Heading at Impact" drivel is the result of BEA's use of "En Ligne de Vol". Words have meaning, and always be sceptical when reading prose by folks are get paid to write.
Everything is not so randomized considering an impact attitude.
If this was completely random, with a 10 margin of error on three axis, you'll have 46,656 attitudes possible (36^3). Here, at most, we'll have about 36 attitudes left to guess about the right one, as both roll and pitch are already fairly described.
Now, give us a break about your "En ligne de vol" rantings.
S~
Olivier
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Old 12th May 2011, 15:07
  #1229 (permalink)  
 
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Bear

You have just described my frustration at the "conclusions" bright people have made re: this crash.
This is exactly why I had asked the question earlier - How do we know the info relative to LKP and altitude is absolute? I know about earlier declarations provided by BEA etc, but using this data as fact, and relating it to the now known actual resting place of the airplane, it simply does not make dough. Noting the map of the debris field, I think one can make a reasonable deternination of the direction of flight when the airplane made contact with the water.
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Old 12th May 2011, 15:12
  #1230 (permalink)  
 
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The only item I cannot find on the new map is the THS or is this still attached to the item labelled rear fuselage section?
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Old 12th May 2011, 15:16
  #1231 (permalink)  
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The victims are telling a story, as they will. Those recovered on the surface have been identified, and returned to family. Those on the bottom have more to tell. Where were they seated? What injuries have they that will describe 447's path downward? What of the final inventory of these souls?

To abandon them on the bottom may be out of concern for the families, if so, that is laudible, but not proper. The proper thing to do is to recover remains to the surface. If a family member of mine, I would lobby and spend unto bankruptcy to retrieve my loved one(s). If possible, this recovery must be done to preserve the victim, money is NOT an excuse to abandon them.

Do NOT forget the victims who were not recovered on the surface, it is certain they did not retrieve all the floating victims.

INVENTORY. Perhaps photographically, an inventory of victims has been done, and mapped.

An INVENTORY of the pieces found in this debris field must be subtracted from a total at launch, to determine how much is missing from the complete plane. This will also have bearing on "Intact at Impact".

The debris in this location is all heavy. Is there no more debris West of this location?? Lighter things??

Define INTACT. At what distance from the primary location are these things??

All we know, and may ever know, even if the machines tell us everything they know, is that the CORE of the a/c's airframe was present at impact. Was it missing many things at impact that point to a disintegration prior??

DISINTEGRATION, a coming apart, does NOT mean complete. On a scale of degradation, I believe it virtually certain that some pieces were lost prior to impact, but this is an OPINION. ACARS does not report as if it has a virtual and complete result of an airborne "Walkaround".

bear
 
Old 12th May 2011, 15:18
  #1232 (permalink)  
 
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They've recovered five seats, captain's, co-pilot's, "fourth occupants", and a double seat (cabin crew?). So I don't think it is established that the two recovered bodies were sitting in the captain's and co-pilot's seats.
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Old 12th May 2011, 15:19
  #1233 (permalink)  
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wes wall

Indeed. The Chinese say: "A half Truth is a whole LIE". No moral judgment from me, but extrapolation is ok, certifying extrapolation is doubtful.
 
Old 12th May 2011, 15:32
  #1234 (permalink)  
 
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The article in the Guardian newspaper regarding the press conference today originally stated that one of the bodies was seated in a row of two or three seats.This now seems to have disappeared and the article has been rewritten and is now much more vague as to the location of the second body
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Old 12th May 2011, 15:32
  #1235 (permalink)  
 
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Gutten tag jcjeant,

I am no investigator, but mindset is clearly not a quality associated with inspectors of accidents. You and bearfoil steadfastly peddle the notion that at the end this aircraft had a degree of directional stability no better than a falling leaf, and present it as indisputable fact. Although bearfoil has recently gone quiet on the subject, he still believes instinctively that the fin separated in flight at some point.

Yesterday evening, you asserted:
Other than an academic point of view .. what is the importance of the "trajectory" when a/c hit water or a/c heading for the investigation of the accident ?
Maybe few seconds before the a/c impacted with water the "trajectory" or "heading" was different...
Seems to me as a "random thing"

The inference of what you say is that either the trajectory, including track, was constantly and quickly changing at random, or that the heading and track bore no relation to each other. At this time, there is no evidence of absence of the vertical stabiliser, so to make the assumption would be unsupportable. Therefore, the burden of proof lies with you, in the present absence of the FDR traces, to prove not just that a deep/super stall was reached at some point, but that this condition would somehow render the whole surface of the tall fin ineffective at preventing sideslip.

Today, you write, sarcastically:
"I must be dumb .. lol .. as I don't understand ..
If the "heading" of the plane at sea contact is the same (or like) of the one of the normal route .. or if the "heading" is reverse of the normal route .. or even perpendicular of the normal route ... what this would indicate about angle of descent .... or track-mileage"

Unless the aircraft develops 180 degrees of sideslip, a reciprocal heading at impact would imply, at the very least, a turn of about 180 degrees in track. This would rule out a track distance from the LKP of less than 5nm. Are you suggesting that would be of no interest?

Quote:
"I don't see how find the track of the plane if I know the altitude LKP and the time to impact and the heading at impact ...
With these 3 data only .. the equation cannot be solved
There are many more unknowns"

True, and we don't even know what the altitude was at the LKP. These are the reasons that I said "some indication". The fact that these data are insufficient in themselves does not justify their being ignored. We must always seek for, and try to assemble, more and more data, until we start to solve your "equations".
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Old 12th May 2011, 15:42
  #1236 (permalink)  
bearfoil
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Scott

You are wrong, and do NOT presume to tell me what I think. The VS may have been damaged in flight, perhaps mortally, but loss of VS has happened both whilst airborne (587), and at sea level, (Perpignan)., and thus far it is not possible to describe its location at impact. It is you who have stubbornly rejected all opinion, and seem to embrace something BEA have not reported as a fact ever. You need an open mind on this matter, imo.

edit. Hint to Chris, jcjeant uses question marks, yet you state as fact that he is concluding facts?? This is an amateur forum, blessed by the presence of some seemingly talented experts. Chill, don't take yourself so seriously.
 
Old 12th May 2011, 15:44
  #1237 (permalink)  
 
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Originally Posted by Saturn V
They've recovered five seats, captain's, co-pilot's, "fourth occupants", and a double seat (cabin crew?). So I don't think it is established that the two recovered bodies were sitting in the captain's and co-pilot's seat.
Go figure! They don't even said that those cockpit seats were still occupied by anyone.
As for the victims, the Judiciary Police declaration is that they will attempt to retrieve ADN from those two bodies (bones). As they were heavily degraded during the recovery process, and that there is no guaranty of success by lack of precedent in such condition. They still don't know if it will be possible. If it is not, it is crystal clear that they won't raise any more victims. I don't think either that it would be that usefull for the crash investigation if all those data memories are fully readable.
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Old 12th May 2011, 15:50
  #1238 (permalink)  

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Chris

Looking at the debris field, there are a few observations to be made :

1/- Suppose the aircraft hit the surface flat, with no forward displacement of any sort (i.e that's the result of either a stall or a flat spin, right ?)
Looking at the solid, densest parts one could find in this mapping, we should find the silhouette of the airplane.
Not so
2/- Now let's pose a forward displacement with some momentum at the decelerationat the water surface :
The densest parts we're talking about will be spread on the field by their order of impact / destruction of the structure around them.
Here, that's the case : The sidesticks touched the bottom before the THS jackscrewwhile there was some residual displacement.

Therefore, whether one likes or not the BEA's *ligne de vol* expression, their posit of an "attitude equivalent to cruising attitude", a high vertical speed and "some" hoprizontal speed is quite well matched.
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Old 12th May 2011, 15:52
  #1239 (permalink)  
bearfoil
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takata

There is a facet that is clear at this point that has to do with civil and legal procedure, not just the search for TRUTH. From now on, the outcome of this investigation has direct bearing on civil procedure, liability, and whose pockets empty. Those responsible will do everything conceivable to mitigate loss. Some will have the appearance of compassion, don't you believe it. This is an enterprise, the repercussions of this accident will change the direction of how people travel, and how commerce is conducted, for years to come.

Lemurian

BEA's proposition that the a/c struck as it did is compelling, and I believe very likely exactly as it happened. My issue was with the report's propaganda, not the evidence... By the way, it is not certain she was heading West, she could have hit with her nose pointing East, and the lighter things backtracked on descent and dispersed "beyond" West of the heavy stuff.

From the look of the debris, it cannot be completely ruled out that impact was not nose first, and for many reasons, but also either WEST or EAST directed.
Even with the final report, most of the conclusions will have only "percentages" of certainty, they will be weighted as the other evidence instructs, imho.

Last edited by bearfoil; 12th May 2011 at 16:02.
 
Old 12th May 2011, 16:01
  #1240 (permalink)  
 
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Chris Scott

Wrong, it should be Guten Tag.
Right, you are no investigator.

As Bearfoil says..This is an amateur forum, blessed by the presence of some seemingly talented experts. Chill, don't take yourself so seriously.
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