AF 447 Search to resume
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Bluestar51
I have no reason to support it, but my surmise is that there are very large (relatively) pieces of 447 on the bottom, to include engine pylon and wing "unit", complete wing box, perhaps to include a fair amount of outboard panels w/ rib and spar remnants.
I use the Turkish accident as a metric; large down velocity, less than flying horizontal, and a tail first hit. That was a twin, and failed in historical fashion given the energy parameters. Three sections: fore, wing box and wing(s) and aft, with tail. The Vertical, if it failed as described in the report, may have started down with the rest of the tail, but released and floated to the surface.
Have a Lone Star on bear, and some Bob Wills Music. Adios.
I have no reason to support it, but my surmise is that there are very large (relatively) pieces of 447 on the bottom, to include engine pylon and wing "unit", complete wing box, perhaps to include a fair amount of outboard panels w/ rib and spar remnants.
I use the Turkish accident as a metric; large down velocity, less than flying horizontal, and a tail first hit. That was a twin, and failed in historical fashion given the energy parameters. Three sections: fore, wing box and wing(s) and aft, with tail. The Vertical, if it failed as described in the report, may have started down with the rest of the tail, but released and floated to the surface.
Have a Lone Star on bear, and some Bob Wills Music. Adios.
Last edited by bearfoil; 20th May 2010 at 01:45. Reason: change meter to metric
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Update: "Seabed Worker" - position
The following are the latest positions:-
19 May 2010 19:41 Hdg 092.6 Spd 02.3 3°04'52"N 30°51'54"W
18 May 2010 20:14 Hdg 304.0 Spd 01.3 3°08'23"N 30°52'48"W
They have been added to the graphic in post #1093
mm43
19 May 2010 19:41 Hdg 092.6 Spd 02.3 3°04'52"N 30°51'54"W
18 May 2010 20:14 Hdg 304.0 Spd 01.3 3°08'23"N 30°52'48"W
They have been added to the graphic in post #1093
mm43
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which suggests that most of the SW unexplored regions of the 40 NM circle are rocky.
Or refer directly to http://www.bea.aero/fr/enquetes/vol....hom.050609.pdf page 4/8.
Jeff
Last edited by Hyperveloce; 20th May 2010 at 17:19.
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but my surmise is that there are very large (relatively) pieces of 447 on the bottom
ww
Mudslide
There is always a chance that the debris triggered a mudslide when impacting on a slope and got buried. Heavy pieces like the engines would be more likely to be buried while lighter parts might "float".
Uh-oh! Now there's a thought. What if the debris got buried...so do I understand this right? The side-scan sonar being used now, effectively builds a picture of the ocean floor. So a mudslide could conceivably hide enough of the wreckage to make it unrecognizable? Does that sound feasible?
Assuming so, are there other techniques that could be used to search? First thought to pop into my mind - magnetic anomaly detection (MAD). If there enough metallic content to make this a feasible proposition?
- GY
Assuming so, are there other techniques that could be used to search? First thought to pop into my mind - magnetic anomaly detection (MAD). If there enough metallic content to make this a feasible proposition?
- GY
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MAD Effective Range
Assuming so, are there other techniques that could be used to search? First thought to pop into my mind - magnetic anomaly detection (MAD). If there enough metallic content to make this a feasible proposition?
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Mudslide
Originally Posted by RatherBeFlying
There is always a chance that the debris triggered a mudslide when impacting on a slope and got buried. Heavy pieces like the engines would be more likely to be buried while lighter parts might "float".
Couple that with likelihood that the a/c sank in pieces, spread over at least a couple hundred meters, and there is even less chance that all of it could be covered.
Originally Posted by GarageYears
The side-scan sonar being used now, effectively builds a picture of the ocean floor. So a mudslide could conceivably hide enough of the wreckage to make it unrecognizable? Does that sound feasible?
Originally Posted by GarageYears
Assuming so, are there other techniques that could be used to search? First thought to pop into my mind - magnetic anomaly detection (MAD). If there enough metallic content to make this a feasible proposition?
How many parts of an a/c are magnetic? Not the aluminum or titanium. Likely the engines have enough iron to to be detectable, but at 5m length, you would have to be within 20-50m to detect one. Flying a sensor within 10-20m of the bottom is difficult in this terrain, and flying lines only 20-30m apart, to increase the likelihood of detection would reduce the search rate far below that achieved in phase 3.
Sub-bottom profilers use low frequency sound (a few kHz) to see below the bottom, but they also have narrow coverage in order to have the resolution required to be useful.
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Would mud 'disturbed' by the impact of an item be detected by the array of equipment deployed, that is would the different textures of the 'disturbed mud' be 'seen' as different to the original, long time settled mud?
Mike
Mike
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Update: "Seabed Worker" - position
The following are the latest available positions:-
20 May 2010 17:45 Hdg 224.7 Spd 00.4 3°07'21"N 30°55'15"W
20 May 2010 16:35 Hdg 227.3 Spd 00.8 3°10'50"N 30°51'41"W
20 May 2010 07:20 Hdg 147.3 Spd 00.6 3°10'46"N 30°50'43"W
20 May 2010 05:33 Hdg 001.5 Spd 00.6 3°10'21"N 30°47'28"W
The following graphic shows them in orange -
IMHO, the area in the southeast corner of the above graphic is a highly improbable location, but you never know. I would have expected the remaining area to the southwest to have had priority, and hopefully it will get done.
At this stage there will be less than a days searching left.
mm43
20 May 2010 17:45 Hdg 224.7 Spd 00.4 3°07'21"N 30°55'15"W
20 May 2010 16:35 Hdg 227.3 Spd 00.8 3°10'50"N 30°51'41"W
20 May 2010 07:20 Hdg 147.3 Spd 00.6 3°10'46"N 30°50'43"W
20 May 2010 05:33 Hdg 001.5 Spd 00.6 3°10'21"N 30°47'28"W
The following graphic shows them in orange -
IMHO, the area in the southeast corner of the above graphic is a highly improbable location, but you never know. I would have expected the remaining area to the southwest to have had priority, and hopefully it will get done.
At this stage there will be less than a days searching left.
mm43
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Originally Posted by mm43
IMHO, the area in the southeast corner of the above graphic is a highly improbable location, but you never know. I would have expected the remaining area to the southwest to have had priority, and hopefully it will get done.
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originally posted by auv-ee ...
It just seems like the areas of low pinger reception probability should have the highest priority for search.
It just seems like the areas of low pinger reception probability should have the highest priority for search.
We don't know when Emeraude visited the area, and consequently if it was late in the battery life, there could have been a marked drop in the pinger output level.
mm43
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Update: "Seabed Worker" - position
Latest positions follow:-
21 May 2010 16:35 Hdg 198.5 Spd 10.5 3°13'34"N 31°11'59"W
21 May 2010 06:02 Hdg 245.2 Spd 01.8 3°10'04"N 30°48'55"W
21 May 2010 04:23 Hdg 258.6 Spd 01.0 3°10'51"N 30°50'10"W
20 May 2010 19:36 Hdg 125.4 Spd 01.3 3°09'08"N 30°48'28"W
Note:: Not all have been plotted, and it seems that the area to the east they have been working on is now complete and the Seabed Worker is now engaged in tending her AUVs in the remaining area to the west.
Sometimes the "blinkers" go on and subsequent knowledge gets tainted by the "already known". In this particular case:-
KNOWN
1.. A position sent at 02:10:30z.
2.. A number of ACARS messages indicative of an upset.
3.. The location and condition of found bodies and debris.
4.. Aircraft impacted the ocean in an intact condition [BEA].
5.. No reported tell-tale signs of overspeed damage to aerofoil surfaces recovered.
6.. Satellite data, e.g. MeteoSat[wx ir images], OSCAR[surface current], QuikSCAT[10m winds].
7.. Limited drifter buoy data.
8.. No pingers were detected in areas searched using USN TPLs
9.. Possible pinger detection on reanalysis of Emeraude sonar tapes.
10.. No bottom debris located during sidescan searches.
UNKNOWN
1.. Why the aircraft got into a LOC situation
2.. How long the aircraft continued flying.
3.. Where it impacted with the ocean.
So, as you can see, the "Known" is actually a lot, whereas the "Unknown" is quite small. Logic tells me that with the correct approach and open minded analysis of the "Known", methodology can be developed to narrow down a likely impact position to no more than a 5NM radius (78.5NM2).
The biggest factor in the backtracking of debris, is knowing how accurate the surface current and wind data is that you are trying to work with. That can be dealt with in this case by careful analysis of the track each individual item found will have traveled over the 12 or so days from the location of the first to that of the last. Comparison of the plotted debris path and that of the OSCAR surface current data along with the QuikSCAT wind data will allow meaningful corrections to be applied to the satellite data which can then be used to adjust the data for the earlier 6 days for which we have no surface plots.
The whole reason behind this approach is to minimise the affect that that one erroneous piece of data will have on the outcome. So rather than having lots of erratic tracks drawn all over a chart, the amalgamated smoothed lines will all lead to a near common point.
Looking at the Vertical Stabilizer which had a reasonable amount of windage affecting it, and the Port Outer Spoiler which effectively had none, it is obvious to me that a retrace of their individual tracks accounting for both current and wind where appropriate will show that at a critical point the V/S became caught in the North Brazil Current and the Spoiler headed NNE toward the Equatorial Counter Current. Every other item's position will relate in one way or another to these tracks, which in the case of the V/S can be adjusted for the windage to reveal the mean current it traveled in.
Anyway, here's hoping that this last area to be searched will reveal the hidden!
mm43
21 May 2010 16:35 Hdg 198.5 Spd 10.5 3°13'34"N 31°11'59"W
21 May 2010 06:02 Hdg 245.2 Spd 01.8 3°10'04"N 30°48'55"W
21 May 2010 04:23 Hdg 258.6 Spd 01.0 3°10'51"N 30°50'10"W
20 May 2010 19:36 Hdg 125.4 Spd 01.3 3°09'08"N 30°48'28"W
Note:: Not all have been plotted, and it seems that the area to the east they have been working on is now complete and the Seabed Worker is now engaged in tending her AUVs in the remaining area to the west.
HarryMann wrote in part ....
... maybe 'blue sky' thinking is inappropriate ...
... maybe 'blue sky' thinking is inappropriate ...
KNOWN
1.. A position sent at 02:10:30z.
2.. A number of ACARS messages indicative of an upset.
3.. The location and condition of found bodies and debris.
4.. Aircraft impacted the ocean in an intact condition [BEA].
5.. No reported tell-tale signs of overspeed damage to aerofoil surfaces recovered.
6.. Satellite data, e.g. MeteoSat[wx ir images], OSCAR[surface current], QuikSCAT[10m winds].
7.. Limited drifter buoy data.
8.. No pingers were detected in areas searched using USN TPLs
9.. Possible pinger detection on reanalysis of Emeraude sonar tapes.
10.. No bottom debris located during sidescan searches.
UNKNOWN
1.. Why the aircraft got into a LOC situation
2.. How long the aircraft continued flying.
3.. Where it impacted with the ocean.
So, as you can see, the "Known" is actually a lot, whereas the "Unknown" is quite small. Logic tells me that with the correct approach and open minded analysis of the "Known", methodology can be developed to narrow down a likely impact position to no more than a 5NM radius (78.5NM2).
The biggest factor in the backtracking of debris, is knowing how accurate the surface current and wind data is that you are trying to work with. That can be dealt with in this case by careful analysis of the track each individual item found will have traveled over the 12 or so days from the location of the first to that of the last. Comparison of the plotted debris path and that of the OSCAR surface current data along with the QuikSCAT wind data will allow meaningful corrections to be applied to the satellite data which can then be used to adjust the data for the earlier 6 days for which we have no surface plots.
The whole reason behind this approach is to minimise the affect that that one erroneous piece of data will have on the outcome. So rather than having lots of erratic tracks drawn all over a chart, the amalgamated smoothed lines will all lead to a near common point.
Looking at the Vertical Stabilizer which had a reasonable amount of windage affecting it, and the Port Outer Spoiler which effectively had none, it is obvious to me that a retrace of their individual tracks accounting for both current and wind where appropriate will show that at a critical point the V/S became caught in the North Brazil Current and the Spoiler headed NNE toward the Equatorial Counter Current. Every other item's position will relate in one way or another to these tracks, which in the case of the V/S can be adjusted for the windage to reveal the mean current it traveled in.
Anyway, here's hoping that this last area to be searched will reveal the hidden!
mm43
Last edited by mm43; 22nd May 2010 at 04:37. Reason: grammar!
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Known and Unknown
MM43
Your summary of the "knowns and unknowns" presents a helpful review of the situation to date.
I wish it were so straight forward. The VS weighed about 1800 kg and had an area of 53 m^2.
I estimate only 10% of the surface area of the VS was above sea level and subject to windage. In summary, the VS had a lot (90% submerged) of underwater drag that may have attenuated the wind effects. Note the VS was submerged at a slight angle that may have "dug in" with the wind drag.
Your own estimates of the aircraft's location on the sea floor using OSCAR/QuikSCAT data were particularly well done and the AUVs are searching that area now, but so far... no cigar. So big the question now is....
"what have we missed?"
Could the aircraft go beyond 40 nm in the last 4 (or more) minutes? Did the aircraft continue more or less along her original course contrary to the modeled debris backtracked estimates (models do not always reflect the real ocean). Do the mountainous areas from the Emeraude sonar tapes need to be searched with higher resolution.
I do not know the answer, but this effort is proving to be a challenging mystery, and we all want to find the answer.
However the search is still continuing, and "it ain't over til the fat lady sings"
Your summary of the "knowns and unknowns" presents a helpful review of the situation to date.
Looking at the Vertical Stabilizer which had a reasonable amount of windage affecting it
I estimate only 10% of the surface area of the VS was above sea level and subject to windage. In summary, the VS had a lot (90% submerged) of underwater drag that may have attenuated the wind effects. Note the VS was submerged at a slight angle that may have "dug in" with the wind drag.
Your own estimates of the aircraft's location on the sea floor using OSCAR/QuikSCAT data were particularly well done and the AUVs are searching that area now, but so far... no cigar. So big the question now is....
"what have we missed?"
Could the aircraft go beyond 40 nm in the last 4 (or more) minutes? Did the aircraft continue more or less along her original course contrary to the modeled debris backtracked estimates (models do not always reflect the real ocean). Do the mountainous areas from the Emeraude sonar tapes need to be searched with higher resolution.
I do not know the answer, but this effort is proving to be a challenging mystery, and we all want to find the answer.
However the search is still continuing, and "it ain't over til the fat lady sings"
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Originally Posted by cc45;#1116
Do the mountainous areas from the Emeraude sonar tapes need to be searched with higher resolution.
HN39
So far the search has been heavily concentrated along the planned course from the LKP. There has so far been a small minority of search in the area suggested by mm43. The same search effort along the accident track and possible impact site derived from mm43's work may have been more fruitful, but it's the holders of the megabucks who approve the search plan.
Passing the hat in PPRune likely would not pay for so much as a minute of sea time
Passing the hat in PPRune likely would not pay for so much as a minute of sea time