Aaaah, let us hope there is a debris field below...

It should be noted that the SEABED WORKER's tight position for the last day is within but a few kilometers of mm43's predicted point of water impact, a prediction he made many months ago based upon careful set and drift calculations and charted for us. Once a navigator (I still own a bubble sextant), and knowing how difficult, tedious, and tricky such calcs are, I would be proud to buy the first round, mm43!

http://i958.photobucket.com/albums/a...prediction.jpg

The Google Earth .KMZ file has been updated here.

GB

F/ctl Rud Trv Lim Fault
 

Quote from HazelNuts39:
"From the 1st Interim Report:
o F/CTL RUD TRV LIM FAULT (2 h 10)
Meaning: This message indicates the unavailability of the rudder deflection limitation calculation function. The limitation value remains frozen at the current value at the time of the failure (until the slats extension command is given)."

Thanks for the correction to my previous post, HN39. It explains a lot.

bearfoil,

Purely on the question of this RTLU issue, are you still suggesting that the A330 system is less protective than comparable aircraft from other manufacturers?

Chris

Chris

I think that this aircraft lost all of its control surfaces while airborne. The report would have us believe they were washed off in the impact with the Ocean. Given the wide range of deflections available from the top of cruise, and the a/c's substantial speed, I believe it is a reach to say the surfaces (connected to the a/c) made it to the impact. The surfaces of each of the controls show that they were wrenched out of their mounts violently but symmetrically. The skin in each is remarkably free of punctures, wrinkling, dimpling and warping. The challenge in engineering aircraft is to spread stress across smooth and strong material, so that no one area may be compromised more than another. This approach is specific to air loading, notwithstanding the need for lightweight.

These panels show abrasion at airflow separation areas, but remain remarkably true to specified dimensions, no folding, no warping, no crushing, as would be expected in a water impact while attached.

In other words, those areas expected to fail in aerodynamic loading, hinges, skin, corners, and longitudinal stiffeners did so, absent the curling, crushing, bending and warping consistent with a water entry while fixed in place. I don't know that the 330 is preferred over another type or not, specific to flight control; this accident involved FBW as a 'cause' only collaterally, imo.

Sorry can´t resist to make a few questions, I have read most of the thread(s), and suddenly the scenario of the possible causes have moved to something catastrophic that happened at normal cruise. Does this mean that all that pitot tubes talkings was just total speculation with very little to no relevance for the accident to occurr?

To what is due this change?

Thank you

Not at all. There are many speculative postings in this thread, and each in its small way helps to evaluate what the possible causes MAY have been.

The whole purpose behind this thread is to have the DFDR/CVR recorders found so that a thorough analysis can be made. Only then will the speculation presented as of today have some or no relevance, and in any event I am sure that results will be argued all over again. That is nature of the world that we live in.

mm43

That's not what the reports say. According to report #1, the vertical tail was ripped off in a forward motion by inertia forces:
and report #2:
HN39

new BEA communique (17th of may)
 

Hi there
The BEA has just released a communique in French:
Information, 17 mai 2010
No significant news, the two Remus have covered 500 square km more without succes and nothing about the analysis conducted by Thales & the Navy (to refine their initial estimate of the pingers location) and about the opportunity to send the Seabed Worker south again.
Jeff

I’m with bearfoil on this. I have sat and read intently for months.

Call it visual bias, however the recovered parts speak in the absence of else, here is why IMHO:-

Quote:

---

According to the BEA report the stops were at 7,9°.

---

- CB WX
- loss of att [all uesable] data

followed by

- Possible assem thrust/ rapid wing stall on one side [roll away from sat coverage]
- Hi-alt [aerodynamic corner] - how do most swept wing aircraft behave at high alt in stall, let alone assem thrust and no [att] ref data in sh1t WX?
- Swept wing roll spin [think about lateral loads and reversal on the vertical stab once in to the vertical]
- Vertical Stab lateral tearing of the attach points?!
- Vertical Stab attach point/s above RPB [cabin alt warn]
- Subsequent wing device damage by aerodynamic load in the wrong [non-normal] flight direction [rip up and out - trailing edge in to the air flow]
- Debris recovered?! [break apart at alt is consistent with things like the spoilers/surfaces, galley frame and other recovered bits and pieces that did not suffer high impact hard compression]
- Condition of recovered persons?!
- Cargo bay crew pod, was it squashed and ripped to bits as per high speed compression impact with water? NO

The photo of the circular rip out of the structure below the vertical stab attach points is the one clue that has remained with me throughout.

Super strong alloy structures will only tolerate a certain amount of reversing [lateral pull and rip force] before it roundels like it did in this case. Metallurgists???

Who knows how [and what] remained of the flying surfaces, and how they performed once the aircraft was descending with no forward [relative to track] airspeed initially.

What was left might have regained sufficient airspeed to have flown for a distance once it resumed airflow before further break-up, OR, it might be sitting on the sea floor any number of miles [radius given possible break-up descent trajectories] ahead/around the LKP.

Hideous scenario I know, but I don’t believe this aircraft was [as it was designed to fly - relatively] semi-controlled [forward/airflow flight] intact until meeting the ocean.

I hope like everyone else, that the recorders are found.

underwater sound propagation & multipath
 

Hello. I know that this kind of multipath may happen for airborne EM radar in a look-down configuration (versus the target) over a rough relief, but would it be possible for sound waves propagating in water and sonars (more curvy waverays than EM waves propagating in the air) over a rough seafloor ?
http://img532.imageshack.us/img532/8475/multipath.jpg
If yes, the waveform detection would be correct but the AoA would be largely biased... and I wonder if the new Thales sonar signal processing can/do make use of the real bathymetry as it was measured during the 1st phase.
Jeff

Certainly surface/terrain reflections are possible, in addition to the various forms of refraction, reflection and ducting due to sound speed variations in the water, which have already been discussed. As I am sure is also true for EM waves, the type of reflecting surface and the angle of incidence can have a large effect on the strength of the reflected signal and the amount absorbed or scattered. The ocean surface is a particularly good reflector, but it also scatters or focuses due to the shape of the surface waves.

The 37kHz signal is weak, attenuated by the water, and more easily absorbed and scattered by soft or rough surfaces than are lower frequency signals. I would not expect terrain reflected paths to produce strong signals, though every rule has an exception.

As for localization, it all depends on what Emeraude was using for transducers. An omni-directional transducer will not provide any localization at all, other than knowing that the source is "near" the receiver. If they used a towed line array, they could compute a bearing (with or without left-right ambiguity, depending on various techniques), but no elevation. If they used a two dimensional array, such as a bow dome sonar, they could, in principle, compute bearing and elevation. Any bearing information is likely to be more reliable than elevation because there is usually less horizontal deflection of signals than vertical (because of the prominent horizontally layered sound speed variations). BEA's second report implies that several sensors on Emeraude were used, but it does not detail any of them (not surprised, the details are likely classified). The best localization often comes from crossed bearings when the source is received at different locations. There is no way to directly compute range, because the pinger is asynchronous.

As I said before, I have no idea what sensors or signal processing have been used. However, I would bet that they are mainly trying to extract any sign of the signal, and are likely not bothering, yet, with any ray bending or possible reflections to refine the localization. IF (big if) they really are convinced that they detected a signal from a pinger, then they might now be going back to the environmental data to see if they can guess the path of the signal. I'm not really convinced that it would be possible to learn much from such an analysis, depending on how well they actually know Emeraude's position and how densely they sampled the sound speed profile.

Update: "Seabed Worker" - position
 

Though these are somewhat delayed, the vessel's positions over the last couple of days follow:-

17 May 2010 19:46z Hdg 171.2 Spd 00.6 3°03'54"N 30°58'24"W
17 May 2010 17:55z Hdg 136.8 Spd 01.7 3°02'55"N 30°57'36"W
17 May 2010 09:05z Hdg 265.9 Spd 11.4 3°07'19"N 30°50'29"W
17 May 2010 07:21z Hdg 060.2 Spd 07.4 3°04'57"N 30°56'02"W
17 May 2010 05:40z Hdg 098.1 Spd 06.9 3°05'06"N 31°03'43"W
16 May 2010 20:52z Hdg 097.0 Spd 05.6 3°03'28"N 31°02'06"W
16 May 2010 19:02z Hdg 126.4 Spd 01.7 3°03'43"N 31°01'53"W
16 May 2010 17:21z Hdg 341.6 Spd 09.2 3°00'25"N 30°57'59"W
16 May 2010 08:32z Hdg 067.6 Spd 02.0 3°04'31"N 31°01'57"W
16 May 2010 06:49z Hdg 086.6 Spd 01.5 3°03'53"N 31°03'40"W
15 May 2010 20:10z Hdg 107.2 Spd 01.7 3°03'44"N 31°03'06"W
15 May 2010 18:33z Hdg 254.5 Spd 01.3 3°03'51"N 31°01'32"W

EDIT:: Positions & graphic updated 18/0700z

http://i41.tinypic.com/ff3868.jpg

Some of the times associated with positions previously posted were actually Brazilian Standard Time and have now been corrected to UTC. As you will note, where the vessel is at any given time doesn't imply that anything in particular was going on there. Some positions were as a result of the launching or recovering of AUVs, or while the AUVs were doing their thing, bottom beacons were being placed for the next area to be searched.

When the "Anne Candies" was towing her sidescan sonar, it was easy to plot where she had been, and this is not the case with the "Seabed Worker" operation.

----------------------

auv-ee;

Thanks for that comprehensive description on the reflection / refraction and ducting possibilities of the 37.5kHz ultra-sound signal

mm43

auv-ee, thank you for your answers about the underwater propagation of sound waves & sonars.
Indeed the Thales sonar signal processing derived from the Barracuda program (the future French nuclear submarines) must be classified. The Emeraude is fitted with a massive dome antenna and what it takes for passive detection/goniometry, and I guess that the sonar data collected by the Emeraude can be related to a very accurate datum/position of the submarine (it relies on a very accurate navigation, given its primary mission/constraints). I don't think that the Emeraude went below -600m (max op. depth is also classified): it remained above the highest peaks of the seafloor.
The SHOM slideshow suggests that most of the montainous seafloor of the area of interest is rocky (muddy in its lowest parts/valleys, probably below -3500m) so I guess this offers a good texture for high reflections/backscattering coefficients near specular directions. The high res. bathymetry of the area shows that nearly 10 % of its slopes are found to be between 30° and 50-60° max (among them faults & scarps of several tens of meters).
About the sampling of the speed profile, isn't it nearly linear in the deep isothermal layer ? (or between the sub and the seabed, see the SHOM profiles).
mm43, don't you think that the area 1 should be entirely scanned at the end of this day or tomorrow ?
Jeff

There is a distinct possibility that the rest of Zone 1 will be completed by tomorrow. I expect the vessel's intention is to be at the demobilization port by 25 May, so expect her to leave the zone 3 days prior. I suspect that this search has come very close to where the a/c impacted, but the longer debate will need to focus more clearly on what has been learned and how that will impact on decisions made in directing any further searches.

mm43

Forgive me if this has been discussed already, but in re-reading the Interim BEA report, I noticed that in the wreckage recovered on June 7th (page 102, lower map, also on page 108), there is a piece recovered very close to the last known position, while all the other debris appear to be further north. Do we know what piece this was or have any idea how it got separated from the rest. It would seem to me that either that piece broke off at a different point than the rest (perhaps an important clue of what happened while the plane was airborne?) or that it somehow managed to float in a different direction than all the other debris. Any thoughts?

Update: "Seabed Worker" - position
 

Late again, but here are the latest positions for the vessel.

18 May 2010 18:21 Hdg 316.3 Spd 01.6 3°09'06"N 30°52'02"W
18 May 2010 16:49 Hdg 308.6 Spd 01.0 3°07'43"N 30°50'37"W
18 May 2010 07:52 Hdg 177.1 Spd 00.6 3°10'18"N 30°57'40"W
18 May 2010 06:10 Hdg 130.9 Spd 00.6 3°10'14"N 30°57'38"W

http://i45.tinypic.com/2qmescg.jpg

Indications are that the search in Zone 1 is drawing to a close and so is this extended Phase 3 search.
------------------
It has been mentioned before, but what it was I have no idea. My feeling was that it had broken free from the wreckage after it had sunk, and then slowly made its way back to the surface. If it had been on the surface for say 3 days when found, the backtracked current vector (no leeway for windage allowed) would place it near 2°50'N 31°10'W. If it had left the aircraft while it was airborne - anywhere??

mm43

Is a Phase 4 search scheduled? The search of another zone?

Quote from Hyperveloce:
"The SHOM slideshow suggests that most of the montainous seafloor of the area of interest is rocky (muddy in its lowest parts/valleys, probably below -3500m)..."

Haven't seen the "SHOM slideshow" (?), but has anything been said about the possible depths of the mud in these lower-lying plains and, in particular, the valleys? Sure I'm not the only one wondering...

Thanks for the update, mm43.

Chris

If you are thinking about debris sinking into the sediment and disappearing, that's not likely. Deep sea sediments (as opposed to river out-wash in shallow areas) are composed mainly of the skeletons of microscopic organisms. These accumulate slowly, in a geologic time sense. While I expect that accumulation rates vary greatly, due to variation in density of organisms living in shallow water, the order of magnitude is about 1m of sediment in 2 million years. The sea floor near the mid ocean ridges (as for the AF447 site) have relatively thin sediment deposits because the sea floor is young. The sediments thicken across the abyssal plains approaching the older continental shelves. That is just background.

While I can't say the depth of sediment in this area, I am not aware of any places where objects tend to sink into the sediment, whether thin or thick (I suppose there are exceptions). Deep sea instruments and moorings having solid steel anchors weighing from 100's to 1000's of kg are routinely dropped from ships, and the anchors don't sink out of sight. I'm sure most of the parts of an a/c will be sitting proud on the sea floor, just like the boilers and tea cups from ship wrecks.

Edit: As usual, things are more complex than imagined. More information about marine sedimentation can be found in many sources, for example http://tinyurl.com/2bue2qj contains some data on the composition of sediments near the AF447 site, in the last few slides. Also, this abstract AAPG/Datapages, Inc. Document Citation lists much faster sedimentation rates for the equatorial Atlantic, of cm/1000years, or 1m/50-100Kyears. My figure for 1/2Myears was based on a report of a core of only 10's of meters giving a 65Myr record; not sure where that core was collected. Search first. :bored:

mm43,

After looking at 8U771, the biggest piece may one of the engines.

BS

The debris found floating would indicate the contrary. Check the photographs in the BEA's interim reports and you will note that many large items survived relatively intact. The 8U771 impact was much different.

mm43

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.

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

Hey Chris.
http://j.imagehost.org/view/0757/seabedAF447reshttp://j.imagehost.org/view/0757/seabedAF447reshttp://www.freeimagehosting.net/uploads/0addef4b07.jpg
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

I concur. I believe that the airplane was intact when contact with the water occured, and that break up was minimum. Given that few bodies and limited debris was recovered leads me to believe that the airplane settled to the bottom rather quickly. If true, then the footprint of major components will not be large, however, a miriad of misc items will make the overall area much larger. The deep water would allow items to drift some distant while sinking.
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

Hi,

http://www.pprune.org/5703918-post1096.html

MAD Effective Range
 

Many decades ago when I had some experience with MAD as installed in anti-submarine patrol planes, the effective range was around 1,000 feet. That may well have improved over the years but I would imagine that given the depth of the water in the vicinity of the AF447 crash, any MAD gear employed would have to be carried by some kind of submersible.

Mudslide
 

Possible? Yes. Likely? No. I have not ever visited the bottom of the ocean near the mid ocean ridges, but my understanding is that the rocky parts, seen as a rough texture in the bathymetry, are truly rocky, and the sedimentary parts, seen as smooth texture in the bathymetry, are reasonably level. I am guessing that this is due to the slow currents that exist down there slowly levelling things out. I suppose there are some sediment slopes at the margins, but I don't know. So there probably are few places that a landing object could trigger an slide.

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.

If some part of the a/c were completely covered, it would not be visible to the type of side scan that is in use. However, a recently triggered slide might itself be visible as a track like a scour mark or a rough area in a smooth field.

Detection of magnetic anomalies requires the sensor to be relatively close to the object being detected, and that object has to be magnetic (either having a permeability different from free space, to perturb the earth's field, or having a magnetic field of its own, i.e. a permanent magnet). The detection distance for a perturbation of earth's field probably requires approaching within 3-10 times the longest dimension of the object.

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.

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

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 -

http://i50.tinypic.com/sw66c5.jpg

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

I agree, but not because I know anything about the flight path or debris drift, but solely because the SE corner is a rectangle (G-30) that BEA already marked as having searched for the pingers with a "good reliability index" (second interim report, page 82). It seems as if all the area that was covered by the USN TPLs could have been eliminated from the search, because the TPLs were towed deep and would have heard any functioning pingers. It seems reasonable to assume that, with two pingers, at least one would be audible, unless both pingers failed or landed with the pinger substantially obscured. It just seems like the areas of low pinger reception probability should have the highest priority for search.

Totally agree. For that reason, and subsequent to the SNA sonar reassessment, the SW corner and south of 3°N for about 12NM between 32 and 40NM from LKP falls into the category of rugged terrain. It is from the ridges, slopes and valleys in this not-so-deep area that the pinger signal could have radiated and was faintly detected by Emeraude.

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

1st july
HN39

Thanks - so battery life was in its "twilight" and pinger output would have been reduced by at least 3dB.

mm43

I really do hope BEA or the search team management are keeping a watching eye on this thread - maybe 'blue sky' thinking is inappropriate but that's what comes to mind...

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.

http://i48.tinypic.com/28akow5.jpg
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

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.

http://10.163.140.153/t2.gstatic.com...stabiliser.jpg

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"

Just wondering, does the survey conducted with TPLs also produce audiotapes and, if so, would these lend themselves to re-analysis with the latest Thales software?

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;)