The Flaperon’s Path to Réunion

drifter-screengrabAs As I wrote back in September, Patrick De Deckker is an Australian scientist to whom the French authorities entrusted a 2.5-cm-long Lepas anatifera shell.  De Deckker has analyzed the shell to determine the ratio of magnesium to calcium within it. Because this depends on the temperature of the water in which the barnacle is growing, and the shell is laid down sequentially like the rings of a tree as it gets bigger, the barnacle can essentially serve as a record of the water temperature of the ocean it floated through. This raises the question: can this analysis tell us something about the route the flaperon traveled?

In August, De Deckker told an Australian journalist: “The start of the growth was around 24 degrees (Celsius) and then for quite some time, it ranged between 20 and 18 degrees (Celsius). And then it went up again to around 25 degrees.”

To me this suggested an obvious route of inquiry: all we had to do was sift through the Global Drifter Program for drifters that wound up in the vicinity of Réunion during the months of July or August of any given year (the flaperon washed up at the end of July, 2015) and see which of them experienced that kind of temperature profile.

I asked for volunteers to help sift through NASA or NOAA databases available online, but no one came forward. Fortunately, my brother-in-law John Swart, a database whiz, came to my rescue. He gave me a copy of Filemaker and showed me how to import data from NOAA’s Global Drifter Program.

Every day, four times a day, these drifters transmit their position and temperature via satellite to the nerds at NOAA. Using this location information we can plot how each one arrived in the vicinity of Réunion. In the Google Earth screengrab above you can see the path that each of 16 drifters took from the start of the calendar year to July/August (the data spans from 2000 to 2015). The upshot: many of the drifters started out fairly close to Réunion, and sort of swirled around. Some came from fairly far away, however–some from the northeast, others from the east or southeast (the direction of the 7th arc).

You can view the drifters’ movement by dropping this .kmz file into Google Earth.

So how did all these paths relate to temperature? With Mr Swart’s help I tabulated all the temperature data for the 16 drifters I examined. Here are the results for 12, as much as will fit in a Filemaker chart (click to expand):


Not that, as time passes, the range of temperatures shrinks, as the drifters converge on the waters near Réunion. (If you have FileMaker you can look at the underlying data set here. CSV here. Excel here.)

I should point out that according to the world’s leading Lepas Anatifera expert, Cynthia Venn of Bloomsburg University, barnacles this size are probably only a couple months old, perhaps as much as four months if we want to be really conservative. So we should look for a U-shaped temperature pattern somewhere between day 90 and day 210.

The closest we see to this pattern would, I suppose, be drifter 71030 or 41337. But neither of these experienced water temperature lower than 21 degrees. (Of the four drifters that didn’t fit on the graph,  the coldest temperature experienced was 23 degrees.)

To my mind, this suggests that the flaperon may not have arrived at Réunion through a natural process of drift.

To be sure, there are other possible explanations for this apparent anomaly. We don’t really know, or instance, how accurate Dr De Deckker’s paleothermometry really is. And it may be that by statistical fluke the flaperon happened to wander off into cold water and back again.

But these findings emerge in the context of other hard-to-explain aspects of the recovered aircraft debris:

— As confirmed by French investigators, the flaperon somehow acquired a population of Lepas barnacles even though its natural tendency was to float high in the water

— The majority of the debris has been collected in a statistically unlikely way

— The majority of collected debris is uncharacteristically devoid of marine life

— On the pieces that do have marine life, it appears to be too small given the amount of time spent at sea.

Taken together, these incongruities raise significant doubts about the provenance of the MH370 debris recovered to date.

While the Australian authorities have bent over backwards to explain their analysis of the Inmarsat data and how it lead them to define the seabed search area, they have been completely silent on the topic of biofouling (except to say that it exists). I wonder if it is because, like the French investigators who were unable to reconcile how high the flaperon floated in the water, they are stumped by inconsistencies in their data.

Australian officials have stated that they will release a comprehensive report on their findings after the seabed search is finished. Given that the last ship, the Fugro Equator, has now started its final stretch at sea, and the last mission lasted about six weeks, the search will likely be wrapped up by the end of January. Hopefully we will have some answers soon after that.

133 thoughts on “The Flaperon’s Path to Réunion”

  1. @Jeff

    I followed the link. I stand by my statement relative to the authenticity of the quote. That is why third party reporting is fundamentally flawed. For De Dekker to actually have said that would fly in the face of the statements attributed to him concerning both the onset of growth and CSIRO compatibility. We need De Deckker’s data showing temperature versus time and his narrative to disambiguate.

  2. I’m an aeronaut and can’t get excited about drifters or Lepas. They both tell you whatever you want to believe in. You just have to be selective in your sampling and your choice of experts.

  3. @DennisW, I’m not sure what you mean by “third party reporting.” Robyn Ironsides sent me her interview notes. The source is thus exactly the same as the article.

    I agree with you that we need De Deckker’s data–I’m sure you can imagine that I’ve been doing my best in this regards for quite a long time now. Given the secrecy with which the ATSB is treating all its biofouling data, I believe that we are extremely lucky to have what little we do.

    @Gysbreght, I would invite you to select your own samples and find your own experts in order to examine the data and arrive at a different conclusion than I have.

    As a community, we need less assertion of gut feelings and more roll-up-your-sleeves hard work. (This is not aimed at you, @Gysbreght, I feel you’ve been doing excellent work on the flight sim issue.)

  4. @Jeff Wise

    I read your topics back then and did quite some own research then (on the net..). A lot of possibilities were discussed on your blog.
    One of them you came up with yourself f.i.:

    The Japanese fisher-buoys that sank due to the weight of the barnacles attached over time. Resurfacing after enough barnacles died off.

    An alternative explanation then could be the flaperon sank due to the weight of attached barnacles around ~5 months before beaching to depths were the water was colder and nutricians were far less available.
    Most of them dying off and detached. Only few young ones survived when it resurfaced again. One of them was studied by De Decker.

    Then starting a new cycle of barnacle growth in those last ~4 months after resurfacing before beaching.

    Isn’t that a gentle solution? 😉

    Anyway the topic is most interesting.
    And like @DennisW mentions it’s necessary to have De Deckers data to make any more or less reliable guess at all.
    And ofcourse the French data would help a lot too…

  5. @ROB
    So I did a quick simulation of your case. Simplified route IGOGU to 38S 88.5E at about Mach 0.81. Presumably FS2004 is giving me the great circle route. ETA was 00:36 but my fuel ran out about 00:12 and I glided down until 00:25 hitting water at 36S.

    Critical in the timing is how the turn at IGOGU happens. FS2004 does not cut corners so it goes to IGOGU and then banks at 25% or so to get back on the path. I assigned time of 18:45 during the bank not knowing your exact FMT time, but I was not trying to be exact.

    To get to FMT I had no interest in a trip out to IGARI, so I just did WMKK to IGOGU, and now that I know how to ascend I basically just took off and manually reset the plane at 35000 ft and reset the location to just before FMT. At FMT I adjusted my fuel by wild guess at about 85% MH370 fuel load, knowing FS2004 is much less fuel efficient than MH370. I could have added or subtracted fuel if I needed to at any time.

    The sun came up fairly quickly at 23:47 or so at altitude (FS2004 sun makes immediate jump over horizon at sun up). Water lighted up at 00:02. These effects only approx in FS2004.

    Most obviously once the early sunlight strikes the plane it is lit up like a candle if viewing from the East, as well the contrail. Of course, there was probably quite a bit of cloud cover that day.

    So this (I call it ATSB) route has the advantage it minimizes that period in bright sun and the distance far west off the normal flight paths minimizes chances of spotting (say from air traffic or ships).

    I noticed on FlightRadar24 there is a Sydney to South Africa flight that goes really funny southern path looks like it is all alone between Australia and Antarctica, so that could be a flight path to watch out for.

  6. To add. This could also give an explanation about the different drifting-modes of the flaperon the French observed.


    The flaperon started drifting flat but soon started drifting trailing edge above the surface when partly filling up with water and subsequently the heaviest part (the leading edge) submerging.

    Barnacle growth started on the submerged part of the flaperon and continued for about one year until the flaperon became so heavy it sank to depths with colder water not that far from Reunion ~5 months before beaching.

    Most of the barnacles died off while submerged there and detached/eaten off with only few survivers.
    The flaperon resurfaced drifting more or less flat again (now completely filled with water and buoyancy only from the honeycomb skin) and a new generation of barnacles started to grow.

  7. @Ge Rijn, Thanks for your thoughtful reply. Some thoughts:

    The characteristic of Japanese glass fishing-net floats that makes them unusual is that they are thick, spherical glass and thus able to withstand the great depths of the ocean without losing their buoyancy. Honeycomb composite cells, like almost everything else, would be crushed by the crazy depths of the mid-ocean seabed and so remain on the bottom forever.

    Even if such a scenario did occur, it would only explain the relative youth of the observed barnacle. It still wouldn’t explain the temperature pattern noted by De Deckker.

    As I wrote in the post, I am hopeful that De Deckker’s complete analysis, and more biofouling from others besides, will be included in the promised Australian report. In the meantime we can only grapple with what we have at our disposal.

    Another interesting note, btw: one of the secret French reports indicated that the biggest barnacle found on the flaperon was 39 mm. This is essentially a full-grown barnacle and would be commensurate with a population that settled on the flaperon soon after a crash into the sea. (Though it also could be younger, perhaps even less than a year old.) It’s not clear to me why De Deckker was given a much smaller barnacle to analyze. The point of his analysis was to see what latitudes the flaperon drifted through; the older and larger the barnacle he looked at, the more useful his results would be.

  8. @Jeff
    Good points on barnacles. Also good question as to why De Deckker was given one particular sample. It would be difficult to come to a conclusion on one test sample.

    A survey of the sizes of the barnacles found relative to location on the flaperon would have given us some meat to chew on.

  9. @Jeff Wise

    Yes, I agree. Honeycomb would not resist the pressures of deep ocean. All air would be sqeezed out and with that all buoyancy.
    The flaperon would never have surfaced again after that.
    But 100 to 200 meters (maybe more) would not affect the skin and honeycomb enough to tear it and let the air escape I think. It’s strong material.

    Around Reunion, Mauritius, Rodrigues there are plenty of places the flaperon could have sunk first to depths like this and then resurface again almost clean of barnacles.

    But the 39mm barnacle you mention is very important IMO.
    When there is only one barnacle older than 6 months up to a year or more, the whole hypothesis of an entering of the flaperon within 6 months of the ocean before beaching can be dismissed IMO.

    I’m curious about what Cynthia Venn thinks about this.

    Obviously the oldest barnacle should be the one to study!
    I also assumed De Decker had the oldest one.
    This makes his study virtualy useless IMO.

    I had my doubts before cause only studying one barnacle out of the hundrerds attached (and not even the oldest one) cann’t give a representive result at all IMO.

    It feels to me like another distraction of facts that are not disclosed for some reason or another.

    The oldest 39mm barnacle is the one to study ofcourse the rest is much less important if not useless regarding the drifting time frames and temperature shifts along the way.

    Reason for me to dismiss this study and suggested implications as important for now.

  10. @ROB
    Might be a good day to look at FlightRadar24 to see typical air traffic for MH370. We have already now QFA64 heading from Johannesburg to Sydney it will be getting to 7th arc later today, I think probably a few hours later than 00:19 but let’s see.

  11. @Ge Rijn, If the flaperon floated to the vicinity of Reunion or Mauritius, then sank, stayed on the seabed until the barnacles died, then resurfaced, was recolonized, and rebeached, you again would have solved the problem of the youth of the barnacle, but not of the temperature pattern observed in its shell.

    We don’t know if there was only one 39mm or more. Or even if, possibly, the 39mm figure was wrong. These reports are not foolproof, after all. It seems to me that if I were the French, I would send the longest, or at least one of the longest. I should add that when I conducted my rough-and-ready photo analysis, it seemed to me that the biggest one I could spot in the high-resolution images available to me was approx. 2.3 cm long. This, however, was on the trailing edge, not on the side, where the report said the largest barnacles were living.

    At any rate, while that question remains open, it doesn’t really bear on the fact that a 2.5cm barnacle was collected from the piece, and its shell chemistry suggested it lived the bulk of the middle part of its life in 18-20C water. (If there was indeed a 3.9cm barnacle, then the 2.5 cm barnacle might have come from a second generation, or just represented a cyprid that encountered the flaperon later.)

    The fact that a 3.9cm barnacle would be better than the one we have does not in any way affect the significance of the information we have in hand now.

  12. @Jeff Wise

    Then please give full proof information. If the biggest barnacle wasn’t full proof 39mm it’s useless to consider this also.

    39mm or 25mm makes a big difference in significance indeed as you know.

    Clear evidence about a 39mm barnacle (and probably Cyntia Venn’s opinion about it) is all that is required to clear up this topic IMO.

  13. @All, here is a link to some information barnacles typically grow at a rate of 1mm a day but when they actually attach to objects is unknown. They develop reproductive organs after settlement 120 days at temperatures between 10.2C – 18.4C. But reproductive development takes 30 days if the surface temperature of the water is around 25C. There are people who actually eat these things (shivers). As such they are harvested off vancouver island (BC) on rocks at low tide where they breed in abundance despite the much lower sea surface temperatures. Barnacles do attach to objects in lower temperatures, but need warmer waters to reproduce.

  14. @ed

    Interesting article.
    Gives another light on all those handbags and shoes found there in a same state of detoriation.
    Nothing to prove it came from MH370 though, but it makes one think about it.

  15. @Jeff Wise

    A 39mm barnacle study by De Decker would have most probably given quite other results. That’s why.

  16. When there is only one barnacle older than 6 months up to a year or more, the whole hypothesis of an entering of the flaperon within 6 months of the ocean before beaching can be dismissed IMO.

    you mean 1 barnacle was planted ?

  17. @Jeff

    “@DennisW, I’m not sure what you mean by “third party reporting.” Robyn Ironsides sent me her interview notes. The source is thus exactly the same as the article.”

    What I meant was that Robyn was the third party – parties defined as De Deckker, Robyn, the reader (us). I do not attribute any distortion to your narrative. I am still struggling to feel confident that the barnacle went through the U-shaped temperature profile based on the aggregate of statements attributed to De Deckker.

    I also wonder why there was a singular interview and no follow-ups that I can locate. As far as I know, the ATSB has never made mention of De Deckker’s work. Is that your position as well?

  18. @DennisW, I printed the exact quote that De Deckker told Robyn. I think it’s pretty unambiguous.

    It doesn’t conflict with the CSIRO model per se, in that the CSIRO model doesn’t deal with sea surface temperatures. As for the assertion that the barnacles could be any age, that’s De Deckker’s understanding; I think he’s wrong, but I don’t fault him because that’s not his area of expertise. And whether he’s right or not, it doesn’t bear on his assertion of a U-shaped temperature profile. I guess if he did turn out to be right, it would mean that the barnacle spent, say, three months in warm water, nine months in cold water, and three months in warm water. Or something like that.

    @Ed, the fact that the handbags were all found together in the same condition suggests rather powerfully that they went in the water close by, and recently. If they’d been at sea for two years they would be scattered across thousands of miles of ocean.

    @Ge Rijn, Sorry, I don’t mean to be mean or oppositional, I just don’t understand your driving at. If a 39 mm is, say, 15 months old, and a 25 mm barnacle is four months old, then the last four months of the 39 mm barnacle should match the Mg/Ca ratio of the 25 mm shell. Of course, growing as slowly as it does near its maximum height, that signal will be highly compressed and perhaps unreadable.

    The really interesting part of the 39 mm barnacle would be the oldest part, laid down when the barnacle was just getting started. The temperature signal then would likely give you a fairly strong indication of what latitude the plane went in the water. All the more surprising, then, that they didn’t give a 39mm one to De Deckker.

  19. @DennisW, PS, concerning your final question, no, the ATSB has not mentioned De Deckker’s work, nor has anyone done a follow-up interview–I attempted one, naturally, but was not as lucky as Robyn Ironsides. Historically, it has proven very hard to get scientists who have provided consultation to the search effort to talk to me.

  20. @ROB
    The main thing I notice today (1000 days late) is UAE425 takes off from Perth and potentially has a bird’s eye view of 20-30S 7th arc around 2300-2400 on Path L894. The flights from South Africa to Perth/Sydney did not arrive in time. A number of Perth to KLIA flight stay on closer to Australia around Path N752.

    Implication is the “McMurdo loiter” (if any) before FMT could be timing to let UAE425 clear out, assuming of course UAE425 flew same schedule in 2014. Your proposed course (like ATSB) is so far west nothing I see today is out there, which is an advantage.

  21. P.S. Freddie’s more northerly path crashing near Bali on 7th arc potentially has more air traffic, eg; the Perth to KLIA flights go up that path

  22. @JeffWise

    Poster @Gator on December 16, 2016 at 1:47 PM, was asking for a source to the article (following @DennisW advice google’Barnacles add to MH370 mystery’ and follow first appearing link).

    @Gator questioned:
    «(If you know for a fact he used some form of LA-ICP-MS, then I would feel much more confident)»

    @JeffWise your narrative only elaborates on Dr. De Deckker results, while in the The Daily Telegraph article is written

    The same 2.5 centimetre barnacle was used by both French and Australian examiners — but different techniques applied. “For my analysis, I used a laser to create little holes of 20 microns, over the length of the barnacles. In all we did 1500 analyses,” said Professor De Deckker.


    The French are yet to make public their findings on the barnacles but Professor Emeritus De Deckker confirmed they “differed somewhat” to his own.

    the French looked at the oxygen isotope content [thus, they used ICP-MS] of the shell — which is made from calcium carbonate, whereas Professor De Deckker examined the calcium and magnesium to determine in what water temperature it grew.

    “In order to solve the difference between the French results and mine, we’d need to do more work,” he said.

    “It would cost up to $1500 a day (for additional analyses of the type carried out by the French team) and we’d have to book a machine well in advance,” he said.

    Until the two different studies are conciled, I wouldn’t give much credit to one alone. That could lead to biased conclusions.

    I would be interested in knowing @Gator opinion.

  23. @Ge Rijn. You raised whether such as the flaperon could bob back to the surface before its honeycomb was crushed by depth.

    The rate of loss of buoyancy with depth while elastic would be quite easy to establish. Harder would be depth’s effect on barnacles: what depth and for how long for death, what buoyancy changes during descent and after (eg gas from decomposition)and how long to separate are nice ones.

    The use of such research could extend beyond just flaperon type assembled items to rate of attrition of thinner nominally-impervious flotsam more generally.

    I for one would be surprised if once sinking started it would not continue to the crushing no-return.

    Possibly adding to this, the impression I have from a few photos is that Lepas are neutrally buoyant on their stalks; though I have found nothing factual in support. However if that be the case the issue does not arise.

    I for one have been curious about what effect flotsam attrition would have on drift studies’ statistics. IF it should be that marine growth generally is neutrally buoyant, such attrition will be by loss of buoyancy alone, which would make it easier to tackle.

  24. @David

    In my example I assumed the sinking flaperon due to weight of barnacles would sink to the bottom of ~100 to ~200m (maybe more) deep water leaving the honeycomb intact. It’s just a guess. I don’t know on which depth the honeycomb will be crushed and its contained air escape.
    It could be usefull to test this indeed.

    When sitting stationary on a bottom I assume lepas will die off by lack of feeding opportunities and gradualy eaten away by other organisms.

    I found this study that tells only one species of lepas forms its own buoyance by creating a kind of foam. Without it it sinks.
    All other species need a kind of floatsom to stay drifting:

  25. Small correction; all other floating species of lepas need a kind of flotsam (another small correction of my dutch english again;) to stay drifting.

  26. Can anyone explain why the reverse drift calculations based crash site probability area ends very abruptly in the West at the longitude of Sri Lanka — whereas in the East, the 95% probability area extends beyond Sulawesi into the Banda Sea and the 5% probability area even extends to the East of the Philippines ?

    (Inmarsat data can’t explain this, since as far as I know, this map is not based on the satellite data.)

  27. @L.H.Long

    The flaw of this reverse-drift-studies (like the Geomar-study above as one of the most representitive) is they reversed the whole situation as if MH370 crashed near Reunion.

    Thet put virtual drifters around Reunion and calculated them back on ocean currents going to the East.
    Resulting in mumerous possible crash areas in the Western Indian Ocean. To illustrate, this sentence from the Geomar study:

    “ determine the possible origin of the flaperon. To do so, they release virtual particles around La Réunion and compute their trajectories back in time.”

    This is completely the opposit of what the actual situation has been according to the Inmarsat data (and the found debris).

    The plane crashed in a small area in the West SIO then debris (cq. drifters) floated to the East resulting in numerous possible landing areas along the African coast and islands.

    And this is what the found debris is confirming. Nothing has been found on Indonesian, Sri Lanka, Australian or any West Indian Ocean shores.

  28. Correction..not quite awake yet.. debris(cq. drifters) floated to the WEST.. and..
    no debris has been found on any EAST Indian Ocean shores.

  29. @L.H.

    Hope the basic flaw of this kind of drift studies is clear though.
    Just reverse West and East in my comment and you’ll get the picture I hope..

  30. @Ge Rijn. Thanks for the reference.
    I remember ‘Rolls Royce’ had been heavily colonised but without much buoyancy so suppose their net weight to be not much.

  31. @RetiredF4:
    I am sure ROB will level up if given a chance. After all he is a genius. And at times it is easily done to miss out on significant details in some of all areas of expertise.

    Merry Christmas to you too!

  32. @TBill

    Thanks for checking that out. I had always thought he had researched his proposed end point thoroughly. Self-evident really, when you look at a map of the SIO.

    This flight path was cleverly designed to allow the maximum control over the final emersion into daylight, unlike Gysbreght’s facile method. For example, if he had approached the sunrise from the back (west) at an angle to the terminator line, he would have found it much more difficult to adjust/compensate for a late takeoff or unexpected wind conditions on the flight south. He would risk falling short, and hitting the ocean in total darkness, or bursting into daylight with fuel still in the tanks. Undesirable, either way. Approaching the sunrise from the east makes no sense – all that daylight!

    A flight path that is parallel to the approaching terminator line gives him the best control over how he emerges into daylight.

  33. @TBill

    Thanks. I had always thought he would have researched his intended endopint, to make sure it was remote and unfrequented. Good to get confirmation.

  34. @keffertje, That link appears to be dead. Anyway, that information you cited is wildly inaccurate.

    @Gator, @Luzazul, Yes, De Deckker used LA-ICP-MS.

  35. @Iuzazul @jeffwise

    I’ve been following this blog from the beginning, yet I rarely comment due to my lack of experience/expertise in all things aviation (I’m just a curious person who takes particular interest in the “unsolved”)

    However, I’ve made a career in analytical chemistry, and could certainly shed light on the results of the two barnacle tests… if the results were made public.

    To echo previous comments, I would find it hard to take either report too seriously until going through the raw data. I’ve seen very thin data turned into statements like “the results are consistent with…”, especially by people who are eager to use said results to prove a point they are trying to make.

    I would like to be able to contribute in that way that so many of you already have with the satellite data, and so I do hope we eventually have access to this raw data!

  36. @David

    Yes, I also think the net weight of a complete barnacle won’t be much above the amount of water it displaces.
    I assume the calcium-carbonite parts add to this overweight the most.

    And nice you mention the ‘Rolls Royce’-piece.
    The ATSB is in possession of this piece and with it has an abundance of fairly large barnacles to study. Which they probably did.
    They are not depended only on this one flaperon-barnacle.

    But indeed as @Gator also mentions; without detailed raw data it’s probably impossible to draw conclusions on time scales, temperature shifts etc. based on only one barnacle.

  37. @Gator, I’m extremely grateful for your offer of help. As more information is released, hopefully we’ll be able to make use of your expertise.

    @Ge Rijn, To clarify, the “Rolls-Royce” piece was photographed on a beach in South Africa covered thickly in barnacles, but the photographer left it there. It presumably was then carried by the tide up a nearby river, where it was picked clean, then washed downstream, redeposited on the same beach a short distance away, and rediscovered by another passerby, who this time turned it in to the authorities. So the Malaysians now have it, but there is no biofouling evidence to analyze.

  38. @Jeff
    Graphic reminder of the possible fate of MH370’s passengers.
    May God give the NOK peace this Christmas season.

  39. @Ge Rijn
    Thank you for Richard Godfrey link re: Mike Chillit’s debris reports. But it’s RGodfrey not VictorI, right?

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