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AF 447 Search to resume

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AF 447 Search to resume

Old 16th Aug 2010, 19:10
  #1921 (permalink)  
 
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Bearfoil
Certainly the slick was analyzed as to origin. Must be some mistake that it wasn't covered in the report.
I'd bet against that. A jet fuel slick would not be obvious unless you sailed through it and smelled it. It was largely evaporated 48-60 hours after the fact since jet fuel is pretty volatile and the low viscosity would allow it to spread unconstrained. We only know about it now because it showed up on a satellite radar scan of the area.
If they could find it on another scan in the archives, it would really narrow down its point of origin.
The Drift Group obviously didn't know what to make of it since it didn't fit any of their models, but at least they stuck it in at the end of their report thinking it might be relevant. In retrospect, it was probably the most relevant piece of data they had.
The bulk of that jet fuel had to be on the surface somewhere, at least until it evaporated, and yes, you can bet driblets are still coming to the surface unless the tanks were completely shattered, but having lower viscosity than WWII bunker fuel, the "half life" of the fuel emission is going to be a lot less than the Arizona's.
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Old 16th Aug 2010, 19:56
  #1922 (permalink)  
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Machinbird

With respect, I saw it in a photograph taken from a search aircraft that was on station.

If it hadn't been id'd, BEA couldn't have so skillfully dismissed it as irrelevant. That the a/c was on station is important, it serves to point out the evidentiary value of the sheen observed, and the irresponsibility of BEA in being cavalier with a 'remote' conclusion.

In any investigation, ignoring or witholding evidence is a serious crime. Knowing this, I'm certain the authorities have fully tested and assessed the value of the "slick".

Mach: "We only know of it now because a satellite...." Wait, you then say the report carries a mention of it? Which?

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Old 16th Aug 2010, 20:08
  #1923 (permalink)  
 
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bearfoil...

Are you sure we're talking about the same "slick"?

I have seen nothing to indicate that the "inverse-v" shaped stain we are discussing was ever noticed or photgraphed by an aircraft (or vessel). AFAIK, the image in the Drift Group report (and posted here) was an image from a satellite.

I would be very happy to be corrected.

grizz
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Old 16th Aug 2010, 20:18
  #1924 (permalink)  
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You are certain you do not remember the slick seen very early on from the cockpit (I'm saying C-130)? It was dismissed along with some little debris (not described) South and East of the "Estimated Impact". At this point it should be found very early in the first thread.

edit, There are many references to an oil slick, and no "V" shape is put forth.2June,09....per appendix
a "pollution spot.....etc. I submit that if samples were not taken, it would imply very shoddy practice.

cheers bear

Last edited by bearfoil; 16th Aug 2010 at 20:30.
 
Old 16th Aug 2010, 20:32
  #1925 (permalink)  
 
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Hi bear

Yes I do recall that item (or an item that fits your description) but my recollection is that it turned out (on analysis) to be non-aviation related (such as bunker fuel). Because the BEA made no connection between the two "stains" I have been surmising that they (BEA) decided they were two different items.

So I'm searching now to find the specifics of the one you mentioned (spotted early on) to confirm when and where it was located. That information -- along with confirmation that the satellite observed stain was no longer apparent after 3 days -- would resolve whether two are in any way related.

cheers,
grizz
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Old 16th Aug 2010, 23:36
  #1926 (permalink)  
 
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grizzled, Bearfoil;

The original oil slick sighted by air on 02 June 2009 was the reason the search shifted over 40NM SE of the LKP. A number of miscellaneous debris items (not AF447 related) were eventually recovered from this location, and it was reported at the time that samples of the slick were taken. I have seen no mention of the results, so assume it was negative for kerosene distillates.

It wasn't until surface vessels arrived that the debris located above could be discounted, and this delay let the the real debris "get away".

FluidFlow seems to have developed a means of integrating identified debris and drift positions with the SAR Pollution Spot. I have asked him for some further information, but on first look it appears promising. One has to ask though, how a debris field managed to pass around or through the LKP ~ TASIL track without being sighted until the "Ursula" fortuitously spotted debris on the afternoon of 5 June.

As I have said before, the SAR "search phase" is often compromised when a "little bit of knowledge" can swing the focus off on a tangent, and precious time is lost.

mm43

Last edited by mm43; 18th Aug 2010 at 22:41. Reason: sub. "afternoon" for "evening"
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Old 17th Aug 2010, 00:04
  #1927 (permalink)  
 
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^^^Satellite imagery of oil slicks from natural seeps in the Gulf of Mexico, in 2006. A discussion of the conditions needed for satellite detection of such slicks can be found here.

NASA - Scientists Find Black Gold Amidst Overlooked Data

I'll just comment on the seemingly similar geometry of the appearance of the slick in the BEA report and the NASA imagery.
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Old 17th Aug 2010, 00:34
  #1928 (permalink)  
 
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Quote:
FluidFlow seems to have developed a means of integrating identified debris and drift positions with the SAR Pollution Spot. I have asked him for some further information, but on first look it appears promising.

mm43:
Perhaps your post on another thread "AF447" on 5 September 2009 at http://www.pprune.org/tech-log/37643...ml#post5170393
may match the work done by FluidFlow recently. It certainly seems very similar with comparable results.
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Old 17th Aug 2010, 01:21
  #1929 (permalink)  
 
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SaturnV;

Thanks for the interesting link.

We can only assume that the COSMO satellites failed to detect further signs of the "Pollution Spot" on later passes. That being the case, the substance had either evaporated or had become broken up by sea/wind action to such an extent that the remaining areas were less than the 30m by 30m SAR resolution. That could also be an indicator that it was a hydrocarbon distillate, and could have been kerosene.

In an earlier post, I said that there were 3 COSMO satellites in orbit in 2009, and assumed that they were orbiting in the same plane, i.e. following each other 120 degrees apart. That may not have been the case, and if the polar orbits were in independent planes to each other, there is a chance that there were gaps near the equator in the satellite coverage.

Don't forget, it may have been an algae bloom.

mm43
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Old 17th Aug 2010, 02:29
  #1930 (permalink)  
 
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That's a very interesting link Saturn V. I might add that it is important to bear in mind that the Gulf of Mexico is highly oil prone (delta system with high rates of burial of organic matter). Mid-ocean ridges and thereabouts are not oil prone as they lack organic source material and the sediment to bury them. The oil slick discussed above is highly unlikely to be from a "natural" source. The above is a gross generalisation, but there are very good reasons why oil companies explore continental margins and not oceanic crust.
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Old 17th Aug 2010, 09:55
  #1931 (permalink)  
 
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The Cosmo image gallery at COSMO-SkyMed / CUGS does contain preview images by date/time/position.
Whether it contains every shot taken is another question, but you can see the image the slick was taken from and on the left hand side if you search carefully the slick itself, in lower resolution than the one in the Drift Group report.

The photo of a slick from an aircraft very early in the search is still on the Aviation Herald near the bottom of the page Crash: Air France A332 over Atlantic on Jun 1st 2009, aircraft impacted ocean .
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Old 17th Aug 2010, 10:25
  #1932 (permalink)  
 
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If someone wants to take the time to look, the visible imagery from Terra and Aqua MODIS for June 2, 2009 are available here.
2009/153 - 06/02/09 - MODIS Rapid Response System

The Aqua track does not seem to have been ideal, with respect to AF447

Agua June 2


Terra June 2


The Terra image from the area at 1225Z reveals lots of cloud. For a look, go here:
2009/153 12:25 UTC - Terra/MODIS - Rapid Response System

Last edited by SaturnV; 17th Aug 2010 at 10:36.
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Old 17th Aug 2010, 18:17
  #1933 (permalink)  
 
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early oil slick

As I recall, this was reported in the UK press as being attributed to oil discharged from a ship: quite quickly after the find. Will try and find a link.

Oil stains from Air France Flight 447 could prove plane was not blown out of the sky by terrorists says Brazil | Mail Online

?Oil slick not from Air France flight?, News - World - Mumbai Mirror
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Old 17th Aug 2010, 22:07
  #1934 (permalink)  
 
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VS recovery position.

Can anyone confirm the ‘correct’ location for the VS when recovered. There appears to be a discrepancy between 3.47N and the BEA pic. Or if I missed it, the post where this is given.
Thanks
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Old 17th Aug 2010, 22:19
  #1935 (permalink)  
 
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COSMO-SkyMed Synthetic Aperture Radar (SAR) Satellites

Thanks BackOffice for taking the time to delve into COSMO-SkyMed image gallery at:-

Which leads me to correcting an earlier post where I said that there were 3 COSMO satellites operating in 2009. That was true, but only from September. Consequently, with the lack of satellites operating with the SAR package, the Pollution Spot found on 02 June 2009 was fortuitous, and neither of the two available satellites made any passes over this location during the prior 30 hours.

As the images available from the Terra and Aqua MODIS satellites posted by SaturnV show, the cloud cover and lack of resolution in these "visible wavelength" images is a problem.

D Bru
and Mr Optimistic's links to the FAB press releases and images also reveal that those "oil slicks" reported well to the SE/SSE of the LKP were not relevant. The positions noted in various items published by the FAB's media arm, were always "suspect" (imo) and impossible to work with. They looked good in the graphics! Hopefully the FAB's positions for the photographs that have been published were made available to the Drift Group, in which case they must have been eliminated.

The Pollution Spot (oil slick/stain) we are looking at is not related to anything found by the FAB in their search operation.

mm43
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Old 18th Aug 2010, 23:56
  #1936 (permalink)  
 
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Relevant A330-200 AD

Several reports have recently been received of loose pneumatic quick-disconnect unions on Goodrich pitot probes P/N (part number) 0851HL. These may be the result of mis-torque of the affected unions at equipment manufacturing level. Investigations are still on-going to determine the root cause(s).
This condition, if not corrected, could lead to an air leak, resulting in incorrect total pressure measurement and consequent erroneous Calibrated Airspeed (CAS)/MACH parameters delivered by the Air Data Computer (ADC).
* * * * *
Loss or fluctuation of indicated airspeed could result in misleading information provided to the flightcrew. We are issuing this AD to require actions to correct the unsafe condition on these products.

AD 2010-17-02 effective 22 Sep
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Old 19th Aug 2010, 00:40
  #1937 (permalink)  
 
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mm43...Thanks for delving deeper into those images.

It's rather a shame that nobody in the Cosmo SkyMed operations centre read the newspaper that morning, or we might have had higher resolution images.
Oh well, that's joined up thinking. Now, what surprises might be sitting on some military anti-submarine satellite somewhere.

I was actually very surprised a civil satellite had that sort of capability.
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Old 19th Aug 2010, 09:36
  #1938 (permalink)  
 
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Oh well, that's joined up thinking. Now, what surprises might be sitting on some military anti-submarine satellite somewhere.
Indeed, that would be interesting to know.

On the other hand that part of the globe is probably not amongst the premier targets of military intelligence, i.e. the chance of plenty military satellites taking images of the vast ocean in that area is rather slim, if not Null.

The next question would be: If images would have been taken by military satellites (of whatever Country), would this information have been made available to BEA ??
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Old 19th Aug 2010, 13:24
  #1939 (permalink)  
 
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The next question would be: If images would have been taken by military satellites (of whatever Country), would this information have been made available to BEA ??
Only if wikileaks passed it along to them.
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Old 19th Aug 2010, 17:44
  #1940 (permalink)  
 
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I was ribbing the Cosmo team unfairly, they at least got an image.

The bigger question is why, with the existing technology we have today, nobody seems to put 2 and 2 together. That Cosmo satellite happened per chance to snap the right area 30 hours after the event and, there may be useful evidence there. Did all the satellite operators, civil and military think about taking an image, even if it was sometime after the event, probably not.
A high level U2/TR1 flight over the area the next day may have speeded up identifying where the wreckage could be found, but as far as I know, that didn’t happen either.

We just seem to be using the same search techniques from 40 years ago, which also happens to be the same timeframe for FDR/CVR/ELT development.
Perhaps it’s just unfashionable to find the answers and improve safety.
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