Deriving the Dimensions of the Rodrigues Debris

Though the piece of debris discovered on Rodrigues Island has not yet been definitively linked to MH370, the distinctive pattern applied to one of its sides seems to match perfectly the interior of a Malaysia Airlines 777, as Don Thompson has so astutely pointed out. Therefore, pending confirmation from the authorities, it seems highly likely that this represents the fourth piece of MH370 debris to be recovered from the Indian Ocean since the start of the year.

The first three pieces have been studied in Australia and handed over to the Malaysians. Apart from confirmation that the two Mozambique pieces almost certainly did come from MH370, no further information about them has been released, and it seems unlikely that any will be before Malaysia issues its final report, which is slated to take place after Australia calls off the seabed search in the middle of this year. Therefore anything we are going to learn from these pieces is going to come from studying photographs and videos taken before they were ushered away into official secrecy.

In today’s post I’d like to discuss my attempts to determine the exact size of the Rodrigues debris fragment, and what its dimensions tell us about the size of the marine organisms growing on it. This is important in determining how long the piece floated in the ocean.

 

1- side view
Figure 1

 

In Figure 1 we are looking at the top of the piece, with the “back” of it (the part not facing toward the cabin interior) upward. I’ve marked in blue 12 inches on the ruler visible in the foreground. Based on the relative number of pixels, I calculate the length of the edge in yellow to be 11.5 inches, and the thickness of the piece (red line) as approximately 1 inch. The purple circle shows the approximate location of the “Lonely Barnacle” which I’ll talk about in a little bit.

In Figure 2 we see a close-up of the bottom edge of the piece. Although the object appears to be of uniform width, the hex cells at the bottom have a different orientation from those elsewhere in the piece: their longitudinal axes are vertically oriented, rather than back-to-front:

2- bottom view copy
Figure 2

 

In a comment on an earlier post, reader Ken Goodwin identified the honeycomb material as most likely being 1/8 inch 3 lb Nomex. This would match well with the width of the piece as measured in Figure 1. If the seven cells I’ve outlined in blue above have a total length of 7/8 of an inch, then the total width of the honeycomb portion (green line) is 0.8 inches.

Figure 3 shows the Lonely Barnacle mentioned above. Based on the hex cells it is lying next to, its length appears to be almost exactly 1 inch, or about 25 mm. (Note that what we’re measuring here is the length of the capitulum, in other words the shell.)

3- lonely barnacle small
Figure 3

 

Note that the barnacle might not be lying exactly flat; if its main axis is skewed in relation to the camera its actual size will be somewhat longer, perhaps 26 to 28 mm.

In Figure 2 it’s possible to see that quite a lot of barnacles are growing in area where the surface has become separated from the honeycomb in the inboard portion of piece (the right-hand side in Figure 1). Unfortunately, I’ve been unable to find any good pictures of this area. The best images showing barnacles are of an area at the top of the front of the panel, on the outboard side:

5- vertical
Figure 4

 

4- barnacle farm
Figure 5

 

Based on their apparent size in these images, the largest barnacles appear to be, again, approximately 25 mm in length.

I ran these images past Cynthia Venn of Bloomsburg University, who is perhaps the most knowledgeable person in the world about Lepas growth rates. She identified these barnacles as being Lepas anatifera, with some smaller Lepas anserifera perhaps thrown in as well. She was unable to determine whether the anatifera belonged to the subspecies striata (which reach a maximum length of 35 to 40 mm) or anatifera (which can reach up to 50 to 60mm) but at any rate they are significantly smaller than their maximum size, which they usually reach in six months to a year.

Of their observed length, Venn told me: “They can get that size in a couple of months.”

Note, too, that most of the barnacles that are visible are substantially smaller than the largest ones; if the piece had been floating in the ocean for two years, we would expect a large community of full-sized barnacles, as is seen on tsunami debris of comparable age. Note, too, that the barnacles on the Rodrigues piece are significantly smaller than those on the Réunion piece, the largest of which measured 39 mm.

It is difficult to explain how a piece that has been adrift for two years can have substantially smaller barnacles than another piece that has been floating in the same stretch of ocean–experiencing, that is, the same temperatures and nutrient levels–for only 1.25 years.

 

96 thoughts on “Deriving the Dimensions of the Rodrigues Debris”

  1. @airlandseaman, The timing of my switchover of the comments from the last post to this one was unfortunate in that it was just after your last comment. So that it doesn’t get overlooked, here’s what you wrote:

    “Jeff:

    Headline: “World Famous (former) CNN commentator reasserts that he is sure Putin done it”

    Re: “…all that really means is that you can’t conceive of a group of engineers pulling this off….”

    How many times do I have to say it? I can and have conceived of it, but I can also see that it is so unlikely that it should not be considered when it comes to defining the search area. This idea is up there with Black Holes and alien abductions.

    BTW…Didn’t I send you a schematic block diagram of what it would take to do it back in 2014?”

    I think you did send me a block diagram; indeed the entire spoof theory rests on your expertise, which you very generously shared with me even though you don’t like the theory, which I consider a mark of highest character. You also were instrumental in discovering that even the most highly trained airline pilots have no idea how to turn the Satellite Data Unit on and off. Not to mention your work figuring out how the BFO values were generated. I could go on…

  2. @Trond
    “…, while the rulers of the west are anti-human.”

    really? we have 2 legs, 2 hands, 1 head, 1 heart, and so on … may be, more interesting word than multipolar is multipartner, these days; throw away stupid stereotypes

  3. Jeff:

    One of your better posts here. I hope you can steer the discussion to more scientific efforts like this one.

    Mike

  4. I would have expected the barnacles to be of similar growth rate, similar size between each finding location.

  5. The lack of any commentary relative to biofouling from the people who actually have or have had debris in their possession (France, Australia, Malaysia) is curious. Why do you suppose that is?

  6. There is a possibility we are talking 2 different current streams. Goose Barnacles of this type apparently favour warm shallow water. The lighter pieces could have been washed through deeper water & not picked up the Goose Barnacles until they reached their respective Islands. Of course the flaperon is much heavier & there is a good chance it may have been carried closer to the shoreline. Either way I believe the answer indeed will lie in the behaviour of whatever current streams the objects travelled in

  7. Wouldn’t the heavier pieces float deeper in the ocean currents than the lighter ones? Thus the lighter pieces should have hit shore sooner?

  8. @ROB: ET961 hit a “REEF”, you know those things made out of solid rock? It’s not clear at all that a MH370 would result in fuselage separation. What is clear is that there was a violent landing. Also, you cannot “unlock” cabin doors unless the pressure on both sides of the door are equal.

    As for imploding a door, it would not necessarily have to be unlocked for that to happen: ET961 had at least one opened door in center section: there were very few survivors from that section, and those that did survive were by the front and back center-section gapes (the fuselage broke into 3 sections), where they could have easily been thrown, swam out. They certainly would not have swam back toward center of section rapidly filling up with water to open up the door.

    In any case, they are “plug” type doors, meaning the main fuselage acts as a doorjamb, entailing that in the event of a strong inward force, the only thing holding the door is the latch mechanism. It would be strong, to be sure, but it’s a fact nonetheless that it is easier to implode a door than to explode it.

    @Gysbreght: Yes, there is some dispute about whether the Rodrigues object comes from the 2R or 1R door. But it is obvious that the debris object was subject to extreme longitudinal forces to the front. Therefore, it (the table side) had to be facing forward, and therefore, it could not have come from the left side.

    The object also was obviously subject to strong torsional forces to the right, which is consistent with an attempted ditching where the right wing/engine impacted incoming swell waves, that would cause a roll to the right, and a hammer like smacking of the right, forward fuselage into the water. If the fuselage section was indented some, that would explain the clean, break away from the fuselage wall.

  9. @Michael John, I addressed this possibility in my last blog post, and ruled it out.

    @DennisW, Great question. As I wrote in an earlier comment on the previous post, the word on the street is that the French were unable to get useful results from their flotation test of the flaperon and their examination of the barnacles was rather less conclusive than advertised: the press was told that the size of the barnacles meant that flaperon had to be in the water for 500 days, but since Lepas can reach their maximum size in 6 months to 1 year this claim is not really supportable. In short, I think they’ve suppressed the report because it would have been picked apart.

  10. Re: the barnacles: I see that many of the honeycombs are filled with what looks like could be a calcareous deposit, which would indicate something was attached there, and was later destroyed. It could be that there was a colony of L. australis that competitively excluded warmer water species until they died off.

  11. There has been a lot of discussion on spoofing scenarios. What do we know about the integrity of the data from Inmarsat? I trust them but wouldn’t it be easier just to hack their computers and insert false data? What if all recordings after MEKAR were deleted and replaced by a false data set without flight ID. Are the abnormal BFO’s that were reported after log-on a sign of corrupted data? This would be a lot easier than a drone or land based GES. The perps on board would know that they could then go anywhere undetected because they sent the searchers to the SIO.

    From the Factual Information:
    When the SATCOM link was re-established at the above times, no Flight ID was present.
    5. During each of the two in-flight Log-Ons at 18:25 UTC and 00:19 UTC, the GES recorded abnormal frequency offsets for the burst transmissions from the SATCOM.

  12. the unexpected reboot has always bothered me and I been wondering if it is a way to insert foreign data to resync such data with the normal data stream that is in isat’s data repository. It did take them some time to publish it to the publish as they claimed it were “fleeting” pings or whatever.

  13. Interesting you bring up this topic. I realy like this site. Glad I found it. Hope you wonn’t kick me out for not being scientific or specific enough too soon..
    I’ve got better close up pictures of the piece but it’s easy to do from the youtube-video as I mentioned in an earlier post.
    I read that barnacles have a larvestage of half a year before devaloping their hard parts. This would bring the Rodrigeus-piece to floating around a about a year according the information given.
    Their average live expectancy is 5 to 8 years and they stay attached to the object they chose to live on for the rest of their lives. A year is to short for attachement in an early stage after MH370 vanished.
    But when those goose-barnacles die by other reasons than predation or age do they fall off their surface structure or do they stay attached?
    And by the way excuse me for my englisch not being perfect. I’m Dutch. It was not my choice..

  14. @Warren Platts,

    “there is some dispute about whether the Rodrigues object comes from the 2R or 1R door”.

    I think the divider at door 1R would have the MAS decorative design on both sides.

    “it is obvious that the debris object was subject to extreme longitudinal forces to the front”
    and
    “The object also was obviously subject to strong torsional forces to the right,”

    It is obvious that we don’t speak the same language for loads and structures.

    “that would explain the clean, break away from the fuselage wall.”

    You think a cabin or lavatory partition is attached to the cabin wall?

    Please don’t present your theories as factual.

  15. I agree BTO spoofing seems almost impossible in real time. If someone wanted to lay a false BTO trail to distract from what really happened, a far more feasible strategy might be to…

    a) be lucky enough to have Inmarsat already effectively annexed into your defense department,

    b) decide to alter the data prior to releasing it,

    c) release only a high-level summary initially, to ensure diversion takes root immediately, without having to painstakingly alter every record in the post-IGARI log,

    d) spend 2 months painstakingly altering every record in the post-IGARI log, so that it looks authentic, and believably cross-corroborates the Butterworth radar return, and

    e) viciously attack anyone who gets a whiff of what’s going on, and refuses to play ball.

    Or something like that.

  16. @Ge Rijn, Just to clarify, when a piece of debris goes in the water, it is sought out in quick order by goose barnacles that have already reached the stage of life at which they are ready to attach themselves. So we measure the length of their shells not to determine the age since they hatched from eggs, but the amount of time that has passed since they attached themselves to the floating object. As to your question about what happens after they die, the answer is that the soft part and shell fall off, but leave a ring of glue where the animal was attached. This is quite hardy and can give scientists a good clue that Lepas has been present long after they’ve dropped off.

  17. @Warren Plats. Like to comment on your repley on the Rodrigues-piece, it’s position in the cabin and the visible damage.
    It must have come (if confirmed) from the right side behind the businessclass. If you look at the photo from aussie@500 you can clearly see the diagonal closing curtain with behind it the businessclass starting. And in front of it the toiletdoor.
    About the damage. In the Rodrigues-video you can clearly see the rightside and upperside are teared and bend forward while the leftside and bottom have come off rather clean. Now this bending forward of the metal and the relatively clean leftside, underside and backside lets me think the piece was not forcefully pusched inwards burt forcefully torne out.
    Beside the position of this piece is a flightattendant seat. It’s a macaber thought but when a flightattendant was (still) seated their strapped when the plane hit the water the forwardforce could have ripped the seat and the whole structure out the way we see it now.

  18. @Warren Plats. Little correction on the position of the part. Actualy behind that curtain are 7 businessclass seats and behind that starts economyclass. On the leftside is no toilet behind and no curtain but the ongoing of the rest of businessclass so this wonn’t fit the photo of aussie@500.
    According to the seat layout I have of a Malasian 777-200 it leaves then 2R the only possible position of the part (if confirmed).

  19. Hi @Brock. What you say is not so outlandish (and certainly more believable than hacking or spoofing). Credible BTO numbers are actually not that difficult to make up once you know what they represent. You could do so without knowledge of sat vectors or K value. However, if this was done it was already done by 15 March and a few days later when the “fuzzy elevation” chart was shown at Lido. Those elevations correspond to within 0,1 degree elevation with the BTO numbers as published. I know this because I had the same suspicion and went to the trouble of back-calculating them – and then forward calculating them from the BTO as published. I don’t think we can rule out entirely that “altered” BTO numbers were published, but if they were the homework had already been done by 15 March 2014 – which seems unlikely….

  20. @Jeff Wise. Thanks for not kicking me out yet..;)and thanks for clarification. I understand now the larve stage is another stage than the attachment stage.
    But I also understand now that there can be several colonies coming and going over a lenght of time attaching and falling off.

  21. re – reboots/data spoofing – perhaps there was some flight data they had on hand from other flight paths. So they inserted data for westward flight on next “reboot” then inserted data for the southbound flight on the next reboot.

  22. @Ge Rijn, Marine biologists who study the growth of organisms on floating debris say that the communities tend to become more species-diverse as time goes on, with some individuals dying and others taking their place. I haven’t heard about whole colonies dropping off and new ones growing up in their place. Do you have a reference on that?

  23. Jeff:

    I haven’t followed the bio discussions closely, but since this new blog is on that subject I went back to the flaperon photos to take a closer look. It is possible to scale those photos, similar to what you did. I determined that the Nomex is probably 1/2″, or maybe 5/8″ thick. From that, it appears those creatures are about 1″ in size. I think that suggests that the size of the barnacles can’t be relied on to estimate time in the ocean. As Don and Richard have said elsewhere, the colonies probably don’t start in mid ocean. They start somewhere closer to land.

  24. Did Cynthia Venn or any other marine biologist offer a explanation Jeff? I know you would probably have shared that info but naturally I’m curious about the expert view.

    As for the data I believe that is solid. There are too many variables on potential routes & the SIO was deemed to be the best 1. That said I have my reservations about how the last 2 calculations for ping ARCS were done. I believe the plane transmits on a frequency based on it’s velocity. This velocity is dtermined by either the planes navigation system or the SDUs own inbuilt GPS system. If this calculation of velocity was wrong wouldn’t that mean the data transmit frequency would also be wrong?

  25. Mike, A French marine biologist contracted by the investigators in Toulouse examined the flaperon and found that the largest Lepas anatifera were 39 mm. I’ve communicated with Don about his assertion that the Lepas most likely attached to land, and explained to him that that’s simply not how the lifestyle of these creatures works–I added a citation to that effect to the end of my previous blog post. It’s quite well attested that Lepas begin attaching very quickly, even mid ocean, and therefore the size of the barnacles can be used to estimate the length of time in the water.

  26. @Jeff Wise. I didn’t use the right word with ‘colonies’ I see. I understood that, out of your repley, over a lenght of time groups of barnacels can die and fall off when cicumstances for whatever reason get too bad to survive, other groups of individuals can then replace them when circumstances get better.
    My point is getting more clear the worth of the age of barnacels seen on the Rodrigues piece now, related to calculating the time it spent floating in the ocean .

  27. @Michael John, The only explanation anyone has been able to come up with is that the debris became beach, was scoured by the elements and picked over by predators, then washed back out to sea before being beached again shortly thereafter. I’ll be exploring this idea in a forthcoming post.

  28. http://eol.org/pages/1020694/details

    This is a brilliant page for information on Goose Barnacles.

    Lepas anatifera is a pelagic barnacle that can be found attached to a variety of floating objects, including driftwood, bottles, boats, buoys, macroalgal rafts, and turtles. It can also be found on fixed objects such as rocks and off-shore structures. This species is most abundant in tropical and subtropical waters where sea temperatures exceed 18-20 ºC.
    Range depth: 0 to 2909 m.
    Habitat Regions: temperate ; saltwater or marine
    Aquatic Biomes: pelagic ; coastal
    Other Habitat Features: intertidal or littoral

  29. Airlandseaman,

    Re BTO: “As I have already explained, it is *technically possible* to do it.”

    Thanks for admitting this. In your previous post you wrote “impossible”, which is dramatically different from “improbable”.

  30. @Michael John, Actually, not accurate–as I clarified at the end of my last blog post, Lepas live exclusively on floating debris, not attached to rocks. They have certainly never been found 2909 meters under the surface. Beware internet sources!

  31. Jeff,

    “the spoof that you’re describing, with a ground-based attempt to generate false BTO and BFO values, is vastly more complicated (as you pointed out yesterday) than a aircraft-based spoof of BFO values alone, which would only require the change of a single parameter in the SDU.”

    Yes, it is more sophisticated. However, it would have a number of advantages:

    – BTO spoofing is a way more efficient than BFO spoofing;
    – Ground-based approach is less risky in terms of detection;
    – It is easy and cheap to repeat hijacking using the same approach/hardware/software in the future: don’t need another drone, etc.

    But again, I will consider spoofing only when the data “as is” exhausts itself.

  32. Oleksandr, I don’t know what you mean by “efficient.” As @airlandseaman has quite credibly explained, it’s significantly harder to spoof BTO than BFO. And while you call your method a “ground-based approach,” it still requires someone physically on board the plane to take it over, so now you have operatives both in the air and on the ground, somehow coordinating so that the data generated on the ground matches the radar data. It’s just unquestionably more involved and hence prone to failure/detection. And again: for what? The best case scenario for hijackers who want to create an erroneous impression of where they went would be to spoof the BFO and leave only a vague sense of the direction they headed in, without the precision of BTO ping rings on which to focus a search.

  33. I suppose I’ve read every one of the 20,000+ posts to Jeff’s fine website. It’s too bad that newbie’s continue to regurgitate some of the old, disregarded theories. Here’s a summary of what’s going on. The Inmarsat data is accurate. The a/c hit the SIO at a high rate of speed near the 7th arc. All of the pieces found recently come from 9M-MRO. None were planted. One cannot predict the ocean currents and weather accurately enough to validate or invalidate any given search area. The ocean conditions for the path and buoyancy of each piece contributed to the amount of marine life seen on each piece. The flaperon was damaged and detached by high speed before impact of the plane. So why hasn’t MH370 been found?

    How are we so sure they haven’t found it? Anyone here on one of the search vessels? We know Fugro has a contract to conduct the search area. I’ll guess it’s T&M based. We’ve read that the sonar data is assigned one of three categories: One is “no way,” the next is “we might need to recheck,” and the last is “something looks man-made, we need to get a camera on that.”

    If you wanted a contract extension past the current area, wouldn’t you continue to assign the “no way” classification to most everything and then, when there is only a couple of weeks left, you find a whole bunch of the other two categories? By then the weather will prevent further search and the search restarts in December.

  34. @Warren

    Re the imploding door 2R: I appreciate reefs are hard, and that there is no certainty that the fuselage would have broken up in this case. I know doors can only be opened inflight if the pressures are equal, but at low level, say 1000ft altitude, wouldn’t the pressures be essentially equal?

  35. @Ge Rijn

    Re your earlier post iro flap operation. As I understand it, flaps can be extended when the APU alone is running, ie after both engines had flamed out. Electrical power from the APU would run the two electric motor-driven hydraulic pumps of the central hydraulic system, and this would allow flap extension. The RAT by itself, cannot provide sufficient hydraulic power to extend flaps.

  36. @Paul: re: enough time to fudge:

    Inmarsat data first sent up to “policy makers”: Mar. 10, 2014.
    Finally communicated to “searchers”: Mar. 15, 2014.

    WSJ closing paragraph (Mar. 20, 2014):

    “It wasn’t clear how U.S. officials obtained the initial Inmarsat data, which they analyzed and helped translate into maps. Regardless, people briefed on the probe agree it took longer than expected for the information to spread from engineers and technical experts who cranked out the first version of the data to policy makers and then back down to officials directing specific elements of the searches.”

    http://www.wsj.com/articles/SB10001424052702304026304579449680167673144

  37. @falken

    you said:

    “@Trond
    “…, while the rulers of the west are anti-human.”

    really? we have 2 legs, 2 hands, 1 head, 1 heart, and so on … may be, more interesting word than multipolar is multipartner, these days; throw away stupid stereotypes”

    California has a higher GDP than Russian. I don’t even give the Russki’s any thought. They are largely irrelevant on a global scale. I do worry about their nuclear weapons somewhat. Hopefully they have enough resources to prevent those from falling into the wrong hands.

  38. @Lauren H

    “The flaperon was damaged and detached by high speed”

    Damaged how?
    MH370 had already been flown around like a fighter-jet and with more speed when descending at the start of its journey through malacca strait than a possible crash.

  39. @jeffwise – If the search ends before finding the main wreckage, then the sunken pieces were too small to be recognized or it flew a little further to the southwest on the 7th arc.

  40. @Rob. Imo it’s easier to assume a door could be opened after ditching then before. That makes much more sence if it ever happened on MH370. Pressure would be equel and thats what you want to do first when you want to get out of a crashed plane. Thats the first thing they did after landing on the Hudson naturaly.
    If it ever happened this way with MH370 it could mean that the fuselage was intact and a lot of people were still alive trying to leave the plane. Or it also can mean that only one person was still alive and opened a door for whatever reason. Pure speculation but imo a more plausible explanation of an open door through which a peace of interior could have been washed out.

  41. Ge Rijn wrote:

    “Excuse me. I forgot to add the youtube movie on the Rodrigues-part. Here it is: https://www.youtube.com/watch?v=FJEvqExMHbE&feature=youtu.be
    Take snapshots in the screen. Save them, open, zoom out and you’ll see a lot of barnacles. Not on the surface that much but inside and under the cracks.”

    There’s maybe a better way – use the cogwheel (beneath the video, RHS) to change the quality of the video to 1020p (HD) then click the full-screen button ( ‘[ ]’ further right again). Quite good quality, especially on the close-ups.

    @jeffwise:

    If you pause that video at 1:20 (the close-up of the Nomex, edge-on) there seems there might be some other organisms colonising the hollows in the Nomex – black peppercorn-like things with a series of holes in the top; slightly differing sizes, so maybe younger/older ones?

    Could the marine biologists you are in contact with possibly identify them?

    Then perhaps (?) their habitat / lifecycle /zonal range / rate of growth could be compared to the barnacles.

  42. @Rob. And about operating the flaps. I learned that a 777 has two air turbine pumps which can operate indepently of enginepower or APU. See the links I gave in that post.
    This units provide sufficient pressure to the center hydraulic system to operate the flaps.
    So I concluded a B777 is not totaly dependent on his engines, APU or RAT to deploy the flaps. It can be done gliding by these air turbine pumps. If I made a wrong conclusion I gladly hear it.

  43. @lauren h

    “If the search ends before finding the main wreckage, then the sunken pieces were too small to be recognized or it flew a little further to the southwest on the 7th arc”

    If it had no flaps then there should be a huge debris field.

    With no flaps it could not have flown further as it already was on fume.

  44. @Ge Rijn
    “If it ever happened this way with MH370 it could mean that the fuselage was intact and a lot of people were still alive trying to leave the plane. Or it also can mean that only one person was still alive and opened a door for whatever reason.”

    Let me add another if…..
    If a door or more doors were opened, the slides, which serve also as boats, would have deployed and the ELT´s of the slides, would have started to transmit the emergencyy signal on the UHF and VHF emergency frequencies. If not somebody dearmed the slides before opening or the ELT´s after deployment of the slides.

    As said, too much ifs. It probably never happened, no ditching, no life people, no door opening, no slides, no ELT.

  45. RE: spoofing

    Disclaimer: great job by ATSB, IG et al, 99.9999% sure it’s in the SIO, etc etc. Granted, the probability may be 0.0001%, but I’ll digress for a moment.

    In principle, would it not be sufficient to insert an (onboard) delay unit / frequency shifter in the AES signal chain to process the outbound signal?

    I’ve got guitar pedals that do exactly this to great effect (pun intended).

    The data immediately post-reboot matches fairly closely with the last known radar position. Subsequent data points indicate a southerly direction, therefore an intervening turn (the “FMT”) is necessarily inferred.

    My take has always been: what if the plane simply continued straight, with the intent of the reboot (of a compromised AES) to indicate otherwise? A simple fixed delay (BTO) and frequency shift (BFO) would not suffice, as the trend of the data would still indicate travel toward the sub-satellite point; furthermore, the data at the reboot time would not match the last known radar trace nor prior ground truth.

    So what would solve this conundrum? I would suggest a delay and frequency shift *as a function of time*, with t=0 at the time of reboot (18:25). In this way, the data would

    initially match the prior ground truth (providing the appearance of normal operation), yet skew further and further away from reality as time progresses (producing an inferred path rotated about the actual axis of travel).

    For posterity, by my estimation, for a path continuing along N571, to produce the recorded BTO/BFO data, the delay (BTO) would be on the order of 23 us/min, while the frequency shift (BFO) would be on the order of 0.0005 Hz/min (with an additional fixed offset of about -40 Hz).

    No doubt I’m missing something obvious… be gentle, ALSM 😀

  46. Jeff,

    You are using my “cons” against my “pros” with regard to BTO spoofing. But the question was not about it. It was about feasibility of BTO spoofing from the ground. Was another aircraft/drone required for this?

    We already discussed benefits of spoofing BTO and BFO vs BFO only. A potential hijacker could mimic virtually any desired trajectory, so that a fake terminus could be anywhere. That is why spoofing BTO is more efficient in terms of misleading and minimization of chances to ever find the aircraft.

    Re: “it still requires someone physically on board the plane to take it over, so now you have operatives both in the air and on the ground”

    Yes, indeed. But on-ground support is required for whatever kind of spoofing: aerodrome, handling aircraft/people on arrival etc. A couple of pirates drinking rum in front of their laptop somewhere near Sumatra or Somalia does not make much difference in terms of man-power. A drone also requires support from the ground, does not it?

    Re: “somehow coordinating so that the data generated on the ground matches the radar data.”

    That is easy. Just the aircraft had to be at specified location at specified time, and move at specified ground speed and heading. Then spoofing hardware/software kicks in at the agreed time, while aircraft’s SDU stays down. No communication is required.

    Re: “It’s just unquestionably more involved and hence prone to failure/detection.”

    I strongly disagree with this. On contrary, using drone/other aircraft would be prone to detection. Firstly, radars can distinguish size of an object in the proximity, thus a drone would have to be of B777 size… Secondly, if interceptors were launched, they would not hesitate to shut down a drone. Thirdly, a contact with a drone can be lost. What is a risk of being detected on a boat, or some remote island?

    Now cost-wise. If you consider someone crushed a B777 into small pieces, planted barnacles, smuggled them to a number of locations, and on top of it wasted another aircraft/drone by sending it to SIO, why would not they invest a few man-month time into the development of spoofing software/hardware, which can be re-used again later?

    Re: “The best case scenario for hijackers who want to create an erroneous impression of where they went would be to spoof the BFO and leave only a vague sense of the direction they headed in”

    BFO without BTO does not define direction. Even BTO with BFO do not define direction in a unique way: some assumptions still must be used to complement Inmarsat data.

  47. @RetiredF4. Very unlikely I agree but not impossible as you explain well. It was ment as a repley on a post by Rob were he suggests a door could be opened by someone in flight before a pressumed ditching. I regarded that as even more unlikely.

  48. Lauren H,

    “So why hasn’t MH370 been found?”

    Because ATSB/IG afraids to admit that assumptions must be changed. And the longer is the delay, the harder it will be for them to admit their mistakes.

    The set of assumptions made by ATSB and IG is absurdity. Individual assumptions make sense; but all together they do not hold water. I think it is very unlikely that the aircraft is in the current “priority” area.

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