How Did MH370’s Flaperon Come Off?

In my last post, I reviewed Malaysia’s analysis of the MH370 debris its investigators have gathered. Not included in that study was the flaperon found on Réunion, as it is being held by the French. So today I’d like to look at what the damage patterns seen on the flaperon suggest about the crash, based on the work done by IG member Tom Kenyon and by a reader of this blog, @HB.

On February 3 of this year, Kenyon released an updated version of his report “MH370 Flaperon Failure Analysis” in which he gives an overview of the flaperon’s structure and how it was damaged. He notes that of the six main structural attachment points of the aircraft, the two biggest and most significant are the flaperon hinges (pictured above). They snapped in the middle:

The lesser attachment points failed in a similar way. That is to say, they did not rip away the flaperon structure to which they were attached.

Kenyon observes:

The location of the failure points of Flaperon hinges is consistent with a large singular lateral force or repetitive lateral (or torsional) movement of the hinges in the inboard/outboard direction. If Flaperon was separated from the Flaperon hinge with forces in forward/aft direction or by applying forces to the Flaperon in the extreme rotated up/down direction (beyond structural stops) then deformation of the Flaperon structure due to such forces would be evident. Significant and permanent deformation of the Flaperon structure does not appear to be present in photographs of the Flaperon.

Recall that two scenarios have been proposed for the flaperon coming off 9M-MRO: either the plane hit the water, or it came off as the result of flutter in a high-speed dive. Neither event could reasonably be expect to produce a primarily lateral (that is side-to-side) force on the flaperon of the kind Kenyon describes.

To raise the level of perplexity, Kenyon points out in other crashes involving 777s, failures didn’t occur at the hinges; rather, the hinges remained intact and the material to which they were attached broke. That is to say, hinges are stronger than the flaperon proper. Here’s an example from MH17:

Kenyon concludes that:

No significant evidence of secondary structural damage excludes a massive trailing edge strike and leads the author to conclude that the Flaperon separated from MH370 while in the air and did not separate from the wing due to striking water or land.

In other words, since the damage isn’t consistent with a crash into the sea, we can deduce that flaperon must have come off in the air. The only conceivable cause would be high-speed flutter. However, on closer inspection the evidence seems to rule out flutter, as well.

The reader who goes by the handle @HB is an expert in quantitative risk assessment in the transportation industry and has extensive experience with composite materials. In a comment to the last post, he observed:

For the flaperon… the lift/drag load is normally passed on the honeycomb panel over the exposed surface area then the primary stucture of the component (the aluminum frame of the flaperon) then the hinges then the primary aluminum stucture of the wing.

In a nut shell, those panels are not designed to sustain any in-plane loads either compressive or tensile. They are just designed to resist bending due to uniform lift load on the surface (top FRP layer in tension and bottom FRP layer in compression, the honeycomb is basically maintaining the distance between the layers without much strength).Those panels can arguably take a little bit of shear load due to drag forces on the top skin (top and bottom forces in opposite direction) but not much due to limits in the honeycomb strength.

The second thing to consider are the GRP properties. The GRP is very tough in tensile mode, much stronger than Steel. In compression mode, it buckles easily and only the honeycomb is preventing this. This is by far the weakest failure mode. If it fails, you will see fibres pulled out link strings on a rope failing under tension. For the skin under compression, you will see sign of compression on the honeycomb but the fibres will have to be pulled out as well. Also, a perfect manufacturing does not exist, there are always delamination (small bonding defects) between the honeycomb and the GRP skin to weaken further the compressive strength.

The hinges are usually much stronger as all the load is passing through them (analogy door hinges).

So you could imagine, if there is a large impact the hinges are expected to fail last. The part of the skin that will buckle is expected to fail first.

@HB here is agreeing with Kenyon: it is baffling that the flaperon came off the plane due to failure within the hinges. But @HB goes further, arguing that this type of damage is inconsistent with flutter:

I would tend to agree that the hinges have been subject to cyclic fatigue… the hinges appear to have been subject to cyclic lateral forces which are not expected in any accidental circumstances (take door hinges, for instance, and imagine the hinge fail after 50 times someone is trying to burst through – you can try at home but it is very unlikely to happen). This of course requires a closer look by experts to double confirm. I cannot think myself of any possible lateral force on this part in the first place but a lateral force that will fail the hinges and not the skin which is weaker is very hard to explain. Try with a wooden door and tell me if you manage.

In a followup comment, @HB observes that even under very strong oscillation the flaperon should not be expected to disintegrate. “If hydraulic power is on, fluttering is unlikely to cause any disintegration. If off, fluttering forces are up and down and the hinges are free to move. Lateral forces, I think, would be small in comparison with the vertical forces and not be strong enough to cause fatigue on the hinges.”

Kenyon concludes his report with a list of six questions and issues generated from his analysis. While all are worthwhile, one stands out to me as particularly urgent:

• Why are the official investigators silent on releasing preliminary reports on their Flaperon analysis? Why would France’s Direction générale de l’armement / Techniques aéronautiques (DGA) release photographic data to ATSB and yet chose not to make Flaperon Analysis findings public after such a long period of elapsed time?

To sum up, a close examination of the flaperon’s breakage points does not yield any comprehensible explanation for how it came off the plane, commensurate with a terminal plunge into the southern Indian Ocean.

This is baffling but unsurprising. Every time we look at the debris data carefully, we find that it contradicts expectations. The barnacle distribution doesn’t match the flotation tests. The barnacle paleothermetry doesn’t match the drift modelling. The failure analysis doesn’t match the BFO data. And on and on.

Something is seriously amiss.

292 thoughts on “How Did MH370’s Flaperon Come Off?”

  1. @Ge Rijn

    If that is in fact the case, then why make the hinge out of steel/aluminum at all? Why not a strong plastic composite?

  2. Maybe Im looking at it way too simplified, but the steel hinge and the amount of rivets needed would automatically suggest the structure of the flaperon is much weaker than the hinge. If that weren’t the case, then save a little cash and just pop in two or three rivets and be done with it.

  3. @all
    I don’t like speculating but please note that
    on 9-aug-2012, “A taxiing Malaysia Airlines Boeing 777 passenger plane (9M-MRO), flight MH389, contaced the tail of a China Eastern Airlines A340 plane, B-6050, waiting on the taxiway at Pudong International Airport.No one was injured”
    9M-MRO subsequently underwent a major repair.

    I have always wondered if there was any possible link? Without pointing fingers, could debris come from the disposed materials following that repair?
    This could explain the “why 9M-MRO?” if this event is part of an elaborated plan.
    i am not sure whether photos can be matched or not.

    https://aviation-safety.net/wikibase/wiki.php?id=147571

  4. @HB
    Interesting find about the wing repair.
    Also is worry all the debris from MH17 (shoot-down over Ukraine) has been accounted for – especially the parts now attributed as MH370 debris. Anyone able to verify this?

    @All
    The “debris” has become really problematic.
    Damage analysis of the debris cannot show how it became separated from the aircraft and Drift analysis shows it unlikely originated from the SIO – or maybe even planted.

  5. @Jeff Wise

    Yes ofcourse, it’s not only about the difference in tension-strenght between metal and carbon/fibreglass laminates. It’s also about difference in dimensions and direction of forces between a metal part attached to a laminate part.
    What I meant is when under same tension force and with equal dimension/section a metal piece will break before a carbon/fibreglass laminate piece.

  6. if they replaced the flaperon as part of fixing the wing , then the flaperon with the serial number was not likely in service when MH370 disappeared but was laying around in the warehouse of sorts.

  7. it is a possibility but i am not saying it happened though. I don’t know enough about Boeing AOG maintenance processes for such a case.

  8. @HB. I look forward to the references. As yet I do not see how the natural frequency in bending of a solidly mounted 8” slab of Nomex with carbon fibre skins can be used to predict the divergent flutter airflow of a flaperon, even if that were mounted rigidly at its leading edge.
    While the slab might match the flaperon for length and breadth the latter’s metal stiffening vice that of Nomex would change the frequency I would have thought, as might the different mass distribution.

    Besides that the flaperon cyclic movement which stimulates aerodynamic forces will not be in bending about its nose so much as rotation about hinges well below and torsion. The flutter frequency will depend on its moment of inertia and the stiffness variation from having two, one or nil active actuators at its leading edge. With one active there will be torsional asymmetry, adding to the equation. With none, it will be even more different to the cantilevered plate.

  9. @David, references given in previous page. i can email these otherwise.

    The model does not actually predict “divergent flutter airflow”. To clarify, the model predicts the natural frequency (which is the inherent resonance frequency of the component and not the actual frequency). The flutter test is basically based on the Braodbent Number (which is a function of Speed and implicitely actual frequency of excitation) and flutter criteria. Based on the Broadbent approach airflow is not explicitely modelled and the test is to check whether the natural frequency matches the Broadbent criteria. If yes flutter can lead to frequency resonance and damage.

    It is of course a simplistic analytical model. I am not saying it is the most accurate approach and also the geometry is coarse. Nowadays, FEA is employed to estimate natural frequencies. Unfortunately, i dont’t have access to an FEA tool anymore.
    Nomex modulus of elasticity is virtually negigible compared to FRP. It can of course be accounted but it takes more time to do that and results not expected to change significantly.
    You are right about the mass distribution, this is a limitation in this model as mass is uniformly distributed as opposed to slightly decreasing away from the hinges. If you change the mass to account for uncertainties about this aspect we are still away from the criteria.
    You are also right about the boundary conditions, we are limited in this model. in this case, the FreeFreeFreeFree boundary condition would be the most representative I presume. Both results for FixedFreeFreeFree BC and FreeFreeFreeFree BC are already far away from the criteria.
    Note also this approach does not account for damping factors conservatively.
    The most uncertain element in this model is the lack of detailed knowledge on the through the thickness composite structure and FRP layer orientation.

  10. @Jeff Wise:

    (…) “As @HB has argued, and as Tom Kenyon demonstrated with his pictures of MH17 debris, the metal hinges are stronger than the composite structures to which they are attached.”

    If that were true, the hinges would be too strong and would add unnecessary dead weight to the airplane. Therefore it can’t be true.

    A piece of MH17 debris is shown as an illustration of that erroneous statement. The heaviest element is the hydraulic actuator and its support fixture. That assembly would be subject to large inertial forces when the wing hit the earth. Those forces probably separated that debris from the wing structure. The force exerted by the spoiler fragment (if that’s what it is) on the hinge were probably inconsequential to the separation.

    BTW I believe that the hinges of a B777 door can fail in a crash and leave the door itself essentially intact. But that’s not a wooden door, of course.

  11. @HB. Thanks for that. I had gone through the references you provided but they did not deal with the matters I raised or where this all integrates with Broadbent.

    For example the NASA reference was about panel-type vibrations and the effect of altitudes.

    “.. whether the natural frequency matches the Broadbent criteria.” What reference describes those criteria and their origin?

    I appreciate you comment that the calcs are approximations but I remain unclear as to to whether the outcomes are reliable enough for flaperon flutter prediction, particularly with uncertainty about composites thrown in.

  12. @Gysbreght

    On your remark:

    “BTW I believe that the hinges of a B777 door can fail in a crash and leave the door itself essentially intact. But that’s not a wooden door, of course.”

    In fact there is a good B777 example of a door seperating this way. The left aft door of Asiana 214. You can see the intact red door lying next to the plane:

    http://www.independent.co.uk/news/world/americas/asiana-airlines-flight-214-crash-caused-by-boeing-planes-being-overly-complicated-9562331.html

  13. Tex Posted June 28, 2017 at 3:46 PM: “Maybe Im looking at it way too simplified, but the steel hinge and the amount of rivets needed would automatically suggest the structure of the flaperon is much weaker than the hinge. ”

    The hinge brackets are unlikely to be made of steel. They appear to be integral with the endribs, at least the center section of the endribs. We don’t know the material of that part of the flaperon. It could be either an aluminium alloy or a composite material.

    I’m not sure which rivets you are referring to.

  14. @David,
    You are right to question the Broadbent criteria as in this particular case referred, given the geometry, it has shown its limitations. For the flaperon/wings, i don’t see any reason for not applying these criteria but I welcolme any comment/suggestion.

    Section 3, p3.
    https://www.atsb.gov.au/publications/investigation_reports/1976/aair/pdf/197603014.pdf

    The original paper here:
    http://naca.central.cranfield.ac.uk/reports/arc/cp/0373.pdf

    If you want to discuss offline, I will be happy to do so. Jeff has my email and can forward to you. it will be easier to send attachements and references.

  15. @HB. Thanks for the reference re-posting. I had read both earlier but the Broadbent reference is to a 1957 report whereas the ATSB referred to one of 1954, “Elementary Theory of Elasticity…” It is that I think which explains his criterion beyond what the ATSB had to say about it. I have been unable to locate it and I thought that might be what you intended posting.

    If you have it, would you please?

    As you know the ATSB report at p9 notes that while the criterion had been used to clear the Nomad to fly, an added unconventional trailing edge device led to flutter.

    I suspect a flaperon might be even more “unconventional” to what he had in mind.

    Even if so, his 1957 work is of interest. At p16 he discusses transonic effects prompting aileron flutter. That sort of problem was difficult to predict back then and may still be.

    I wonder how transonic flutter clearance would be demonstrated in a large transport aircraft?

    Still, there is no reason to believe MH370 encounted flutter within its boundary, is there? If not, any further work would best be looking for a reasonably accurate estimation outside; that is probably with a pilot if not engines for thrust and control. Presumably that entails FEA or somesuch. Boeing would have a good idea from its researches……

    If after the above you think there is more about the applicability of Broadbent to discuss, with or without the 1954 report, please let me know and I will ask Jeff for your address.

  16. Tex
    “…This, to me, looks like a mechanically separated piece of decommissioned scrap.”

    Yes it does. There have been doubts about the so called MH370 wreckage for a long time. The context of the finds, regarding timing, location and who.how most of the pieces were found is strange. The simplest explanation for these conundrums is that the evidence was planted, as part of a cover operation to hide the real cause and motive behind the MH370 vanish act.

  17. @David
    You have a lot of courrage to tackle aeroelasticity.

    I don’t have an online copy but you could obtain here.
    https://books.google.com.hk/books?id=FrAOcgAACAAJ&dq=The+elementary+theory+of+aeroelasticity+broadbent+1954&hl=en&sa=X&ved=0ahUKEwin0tm4kuXUAhUHw4MKHevYAucQ6AEIJjAA

    The bottom line is that there has been no official attempt to explain the failure mechanism of the debris. This tension – compression observation is cheap compared to the high profile of this case.

  18. @all,
    The Australian has published a story about the ATSB’s final report on MH370 being pushed back, and the frustration this has caused among the NOK. Since it’s behind a paywell, I’m cutting and pasting it here. The link is http://www.theaustralian.com.au/business/aviation/victim-families-angered-at-further-delay-to-mh370-search-report/news-story/a6e2e9b8864c6a17de4931b91efd9b29

    The Australian Transport Safety Bureau has conceded it could be another three months before it releases its report on its failed search for Malaysia Airlines flight MH370, further angering families of the 239 victims.
    The ATSB had indicated to family members that the report on the $200 million underwater hunt would be finished and published about now.
    But ATSB spokesman Daniel O’Malley has now told The Australian, “we anticipate that the report will be released in the third quarter of this year”, meaning it could be published as late as the end of September.
    The two-year search of 120,000sq km of ocean, funded by Australia, China and Malaysia but directed by the ATSB, ended in January without finding a trace of the aircraft.
    The ATSB came under considerable scrutiny from scientists who had suggested relatively early on that drift modelling of debris from the aircraft found on the other side of the Indian Ocean indicated it came down further north than the area searched.
    Some senior airline pilots and air crash investigators claim the ATSB’s strategy was flawed from the start because it assumed the Boeing 777 had crashed in a pilotless “death dive” rather than being flown to the end and outside the search area by a rogue pilot.
    MH370 disappeared on March 8, 2014 on a scheduled flight from Kuala Lumpur to Beijing. Primary radar and automatic satellite tracking data indicate it doubled back over Malaysia 40 minutes in, before turning south on a long track to the southern Indian Ocean.
    There is an expectation that the report on the search could be used by the ATSB to advance its tacit campaign to have the three governments relaunch the survey in a new 25,000sq km area north of the old one.
    Queensland’s Danica Weeks, who lost her husband Paul on MH370, said the continuing delay in the ATSB’s formulation of its report was increasing the angst of the families.
    “This is our lives they are playing with. We think of loved ones 24/7 and how this could happen; we hang on any, every information that surrounds MH370 and always will until the answers are forthcoming,” Ms Weeks told The Australian.
    “If the ATSB had crossed their ‘t’s’ and dotted their ‘i’s’ on the search, why would it take nine months to produce a report? It’s inconceivable.”
    Despite the plea from Ms Weeks, Mr O’Malley would not provide a clearer timeline for the release of the report, or explain why it had been delayed.
    The delay comes amid continuing outrage among victims’ families at the refusal of the bureau’s chief commissioner, Greg Hood, to grant a Freedom of Information request from The Australian to release assessments of its “death dive” theory by a panel of international experts looking at the satellite data.
    The lack of resolution on MH370 also sparked debate about the need for recorders that could be more readily found after crashes. Airbus has said it will equip its aircraft with new cockpit voice recorders and flight data recorders able to record up to 25 hours of information. One will “be deployed automatically in case of significant structural deformation or … submersion”.

  19. @HB.”This tension – compression observation is cheap compared to the high profile of this case.”

    The Search report might have more on that and on biological analysis if relevant to search area. Conceivably it could add to final plunge and drift data.

    However on the flaperon the French should have imparted their findings to Malaysia, which has investigation responsibility. On the flap, the ATSB was looking principally at evidence of them being up or down. Other findings I suppose would be with Malaysia too, to integrate with their work. Yes their tension-compression assessments to date tell us little.

    As to a specifics requirement for damage analysis and impact reconstruction, there is none much that I can find in ICAO Annex 13 or Doc 9756 pt 4 about investigations and reporting. Both are on line.

    9756 pt 3 8.7.6-8.7.9, Examination of Pieces has a little though that supposes a MH17 type reconstruction.

    http://www.aaib.gov.mn/uploads/9756_p3_cons_en.pdf

    BTW at 9.8 there is a section describing some failure and other aspects of composites and laminates you may not seen.

  20. DennisW
    “…Other “missing” news…”

    Good find Dennis! As usual in this smoke and mirrors world we’re living in, nothing is quite as it seems. Ribbeck Law Chartered seldom appears in court, but hovers up potentially troublesome litigants and sells them on to Colson Hicks Eidson, whose president is Lewis Mike Eidson who came to England as a student and dis time in the US Army Adjutent General’s Corps. Monica Ribbeck “Kelly” is simply a red-herring for lead player Eidson, who I suspect runs controlled opposition for the US Secret Service. The misdirection continues.

  21. @David

    When you look at the list of items that should have been done according the this manual and appear not done: ranging section 3, 4.11, 4.12, 9.
    The lead investigators will have a hard time to demonstrate compliance. There is no excuses for section 4.11 and 9. Hope to see details in final report.

  22. Well maybe the von Ribbecks just figured that the whole affair is dead in the water, and decided not to waste any more time on it?

    It’s still strange though, German aristocrat lawyers, from South America. Somehow this affair has attracted it’s fair share of shady lawyers. I just had a look at Blaine Gibson’s website, he gave up right?

    I still personally like the (‘my’) North Korea theory, especially in light of how China’s attitude towards NK has gone down the crapper in the years since. I know it’s basically Alien-abduction-unlikely but still. Has anyone started taking bets yet on “MH370 place of discovery”?

    However, come to think about it, should NK fall, there’s a very good chance that it is the PLA who gets to PY first and they’d disappear the plane :(. We’ll never know…

  23. @Havelock H
    Not so fast … its already well established a KL – NK air smuggling route. Well documented. Pls expand “your theory” beyond that …..

  24. @David

    With all respect your further analysis is still based on the ATSB assumption the flap track caused the big vertical crack through the seal pan. I ask you to consider this:

    Indeed your keen observation that, if this was the case, the flap-track end had to be ~8 inches before its fully retracted flap position when this impact would have occured.

    While the outboard flap is actuated by screw-jacks (not by PCU’s) which keep it fixed in a certain position independent of hydraulic failure (it would stay fixed in the position it’s in in this case), it’s hard to imagine how the outboard flap could be first in a retracted position when the flaperon is assumed to have hit the outboard flap in line with the flaperon, then later partly deployed to cause the flap-track-end hitting the seal pan and cause that vertical seal pan crack.

    Imo if this was the case it has to be either one or the other; the outboard flap was partly deployed or it was fully retracted.
    So both observations, although from your (and ATSB) point of view quite correct, are conflicting eachother and ruling eachother out Imo.

    I think the problem lies in the assumption the flap-track-end caused the big vertical crack and the flaperon’s trailing edge spar-end caused the dent and cracks in the seal pan and upperskin in that trailing edge positions.

    I still think both assumptions cannot be right.

    First the flaperon’s assumed point of impact into the seal pan.
    This crushed point is not only too far inboard to possibly have hit the seal pan without causing a scratch in or around the dent, it also would mean the trailing edge of the flaperon must have been gone before something like this could have happened anyway.
    Almost the complete trailing edge part of the outboard flap section is intact along the seal pan and there is no impact damage visible behind the dent at all.

    If the flaperon impacted the outboard flap, its trailing edge would have impacted it first if in line. Unless the flaperon’s trailing edge had seperated already before the assumed impact or the outboard flap was deployed.

    I think the only solution is the flaperon could not have caused the dent and upperskin crack there and the flap track did not cause the big vertical seal pan crack.

    The more logical explanation still is Imo the big seal pan crack (and the one towards the inspection door) is a tension crack caused by by a big hit (or several hits) at the underside of the outboard flap.
    The dent and lifted upperskin there are caused by opposit compression forces Imo.

    Another clear indication for this scenario can be seen in figure 13 (zoom in) of the ATSB-report.
    You can see the upperskin right above the vertical crack is deformed inwards and outwards. Just where you would expect compression forces on the upperskin would cause such an effect.

    So @David, although your observations and conclusions are very precise as always I argue your (and ATSB) assumptions cannot be correct.

    And as we all know; deducing from wrong assumptions leads to ever more conflicting information. Which is a good thing for in the end it will ‘kill’ those assumptions (including mine if wrong;).

  25. @Steve Barratt

    Thank you for your compliment.
    Yes, I’m kind of relentless in expressing my views I know but always trying to base them on common sence, locic, objective facts and information available.

    As long as there are no obvious indications the debris (or data) was tampered with and can be explained by natural fenomena in a better way I choose for the latter.
    And Imo the latter is still more logical and possible.

  26. @Ge Rijn. Thank you for your thoughts.

    “ it’s hard to imagine how the outboard flap could be first in a retracted position when the flaperon is assumed to have hit the outboard flap in line with the flaperon, then later partly deployed to cause the flap-track-end hitting the seal pan and cause that vertical seal pan crack.”

    To iterate briefly, I think the flaperon impact broke the flap under upwards and rearwards forces. Elastic flexing reverberations at the flap inboard end then caused track free-end rebounds within the seal pan, the last causing the forward crack. That end had travelled 8″ already. The other end’s separation at the nearby support mechanism followed.

    An alternative to that is the flaperon remained hooked on during this second or two and did more forcing. Perhaps this was while still restrained loosely and briefly at its front by attachment to its outboard actuator as its inboard end pitched up.

    It is easier to see the forward crack caused by external forces than just some residual bouncing about – what I take to be your doubts. However the remaining-hooked-on then would require an explanation other than flaperon release as to why the initial free end strike did so much evident damage to the stiffener, horizontally and vertically.

    You might argue again that water-hammering in a flaps up ditching would reduce this uncertainty but that to me does not explain all this damage, the rearwards forcing or the ‘penetration’ damage.The last looks nothing like compression damage, though again to me.

    As to the appearance of the flaperon rear spar ‘penetration’ as before I do not share your problem with that, though access to a decent photo of the damaged rear flaperon spar would help still. I note that the ATSB, with direct access to the flap and, I surmise, more photographs of that spar, raises no doubts.

    Likewise, I do not think there need be much flap damage caused by the flaperon bottom skin being broken off before or during the penetration, if not edge on.

    You point out what looks like compression damage above the forward crack. With no fastener distress I had hoped it might be a dent from another flaperon impact, maybe that dent under its outboard nose. That would help with an explanation of the last strike but 26, 28 and 14 make it appear (to me) that it is an inflexion in plan-view shape.

    I had looked at it in 26. It looked at first like a hump but not when the download is expanded.

  27. @David

    I guess we have a different approuch based on different assumptions on this matter which leads to different interpretations. And I think we still have too little information.

    I think it would clearify a lot if the ATSB could tell us which cracks and damage show mainly tension failure and which mainly compression failure in and around the seal pan (and other parts of the outboard flap section ofcourse).
    Like where pulled fibres (tension failure) are more evident and where kinked fibres (compression failure) are, like as mentioned in the Malaysian debris analysis on the other debris. I think the ATSB should provided this kind of information also with their debris analysis.

    As you seem to be in contact with the ATSB could you ask for details in this regard?

  28. @Ge Rijn

    You will be lucky to get this information. For the flaperon, we are not even sure ATSB has this information but for other Debris i agree it will be useful. The French Investigation Report should contain minute details if they comply with ICAO Manual of Aircraft Accident and Incident Investigation Part III Section 9 (link sent by David). I had a look at that section and it is very detailed and specific on what findings should be recorded. For composites, it makes even distiction between fibre buckling, delamination, fibre fatigue. For aluminium, it also makes distiction on where the fatigue originates from.
    I am pretty sure that whoever performs this analysis will be baffled.

    My take is Malaysia/ATSB will not spent a penny on this. The reason is that they believe that a power shutdown caused the SDU to stop communicating on the last ping and they deduced a total incompatibility with a ditch scenario (which requites power) and hoping everyone to believe this scenario as fact ignoring all other unmatching data (the list is growing with time).

    If we cannot find what happened analysing satcom data, we probably can learn someting from radar data (we have been told it exists) and debris data (hard evidence). Time to change strategy.

    “If everyone is thinking alike, then somebody isn’t thinking.” G S Patton

  29. @HB

    That’s a nice quote you stated there at the end 🙂

    It could well be the ATSB does not have the detailed forensic analysis on the flaperon from the French. Regarding the French do not approach their investigation as an aircrash investigation but as a criminal investigation it could well be they allready know exactly how the flaperon seperated and in which attitude the plane was when it did.

    It could well be they are obliged by their laws on criminal investigation that don’t allow crucial evidence to be shared with other countries let alone the public as long as the investigations are ongoing.
    It could be they just wait for more information and evidence to show up to make their case stronger.

    Or maybe even have a stand like Australia suggested; they don’t want to damage bi-lateral relations and choose to keep crucial information secret.

    Then I think also the ATSB does not really need the flaperon’s info in detail.
    They have the outboard flap section which Imo could provide all the anwsers the flaperon could bring (except bio-fauling). Maybe even better.

    And as far as I know they did not hand this most important piece over to Malaysia.
    I wonder why not BTW, while they are not responsable for the debris/forensic investigation but Malaysia is.

    That said, I believe the ATSB is completely capable of conducting this kind of forensic debris investigation complying with the ICAO manual.
    And it’s hard to believe they not already did this kind of detailed forensic analysis on the outboard flap allready but perhaps wait with disclosing this till the final report.
    I hope so. And if they (or others) did not investigate it like this yet it’s about time they make a serious start with it and provide information as soon as possible.

  30. Dr David Griffin just presented the newest CSIRO findings at the annual AMSA conference. Their analysis took into account sea surface topography measurements from the satellite radar data, which are used to model the sea currents at the specific date. I am not sure if this was done before in their research or it is the latest addition to the model. The presentation abstract can be found here:

    http://wired.ivvy.com/image/display/account/23127/file/6355657/j/f8649bca96d4e5d8f250bd611c6ab963

  31. @Marijan
    @All

    The abstract of Dr David Griffin’s presentation is on page 151 of the linked document. It reads as follows:-
    Surface drift and the search for MH370
    DR David Griffin, Emlyn Jones, Mark Hemer and Peter Oke
    CSIRO Oceans and Atmosphere, GPO Box 1538, Hobart Tas 7001
    David.Griffin@csiro.au

    The sea-floor search for Malaysia Airlines flight MH370 has now (Feb 2017) been suspended, with no sign of the plane having been found in the area suggested by careful analysis of the Inmarsat transmissions.
    In an attempt to shed further light on the location of the plane, we completed a three step project for the Australian Transport Safety Bureau as follows:
    (1) check that our global ocean model is able to reproduce the long-term drift of undrogued SVP drifters,
    (2) determine, by fieldwork using full-size replicas, whether found parts of the plane drift faster or slower downwind than undrogued drifters, and
    (3) do model simulations of the trajectories of all plane parts and assess the most likely location of the crash, taking into account all available information on where debris has been found, and not found, on shores and during the initial 6-week aerial search off Australia.
    Issues confronted during this work include windage, near-surface shear, Stokes Drift as well as the effect of wave forces on irregular-shaped items.
    The result of this work was surprisingly precise, with a surprising degree of confidence.
    We think the plane is in the region slightly north of the region that has been thoroughly searched, just slightly farther away from the ‘7tharc’ than has been already searched, most likely between 36°S and 35°S.

  32. In my view, this could qualify as new evidence. A new search here will give us a firm conclusion at circa 100pc confidence to convince the unconvinced.
    Whatever the result of this search, it will be conclusive to determine what happened. Since it is not possible to match all the data and budget is not a constraint, i would say why not so long as they keep some budget for microscopic analysis of the debris failure mechanism which should be less than 0.1pc of that budget.

  33. @HB

    In a way I agree with you. Indeed either way a search of this new area will give important results. If they again don’t find the plane it will prove their assumptions have been wrong again. But such a result will tell hardly anything new about where the plane could be else or what happened to it.

    IMO the uncertain and in some ways obvious conflicting results and conclusions of the latest CSIRO studies make this new multi million dollar search a very expensive gamble. And the big risk involved if this search would be conducted is that it will be the final attempt whatever the outcome.

    Far better would be to turn your suggestion around:
    First spend that 0.1 percent of the budget on a thorough forensic investigation of all debris (with independent investigators involved!) and only after this has been done make up your mind about further steps.

  34. I stumbled upon a short intriguing movie.
    A ditching in the Pacific by a Boeing Stratocruiser in 1956 who lost power on both its left wing engines.
    With a happy ending; everyone survived although the complete fuselage broke off behind the wings during impact.

    Interesting to me also is the plane circled around to wait for daylight and to burn all its fuel before ditching.
    Reminders of the Hudson-ditch come in mind when you see the people standing on the wings before resque. But here it all happens in open ocean:

    https://www.youtube.com/watch?v=k3F2jUYgqOc

  35. @Ge Rijn. Sorry, been away. “I think it would clarify a lot if the ATSB could tell us which cracks and damage show mainly tension failure…… ”
    1. I do not think the ATSB would have described the penetration damage cause as they did were there evidence from the fractures to the contrary.
    2. If they have not looked into that there will be nothing they can tell us.
    3. As a general observation, by itself the very broad characterisation of fractures in some composite recovered debris has not helped much.

  36. @David

    No bother, thanks.

    On your logic but paradoxal points:

    1; I agree you would assume the ATSB have described the cause of the penetration damage only after also looking carefully at all evidence from the other fractures.
    They did not (yet) provide any detailed fracture analysis like tension/compression, pulled or kinked fibres etc.
    So we don’t know if they considered other evidence this way to support their ‘penetration assumption’. I call it ‘assumption’ cause the ATSB did not present their conclusions as proof.

    2; If they did not looked carefully this way to all fracture damage they cannot tell us anything about it indeed.
    But then the paradox comes with 1; how did they make the assumption of the penetration without investigating in detail all other fracture damage?

    3; As a general observation I don’t see a very broad characterisation of fractures in the recovered debris as described in the Malaysia-report. It’s almost all tension related damage on trailing edge and engine related parts. I think it would be very interesting if they would find (or have found) compression related fractures in the outboard flap section.

    Only the ATSB can tell if they did a full ICAO compliant investigation of all fracture damage. If they only would state ‘yes or no’ this would be a bit helpfull imo.
    Much better ofcoure if they provide a full damage analysis report of the outboard flap section.

  37. @Ge Rijn
    Interesting video. On the one hand, we have to say that looks intriguing for explaining the lack of debris for MH370. On the other hand, we have to also consider the interior pieces of MH370 (bulk head and video monitor frame). Those pieces look a lot like they got blown out the tail section in a nose dive that would have compressed the cabin air and blown out the internal pieces.

  38. @TBill

    Imo the (only) three found cabin pieces could be better explained by a similar seperation of the tail section or another breach of the hull during a ditch-like event.
    I think in case of a blow out of interior pieces in a nose-dive impact like you suggest there should have been much more interior pieces (and other pieces) blown out and found by now. I repeat again; ~90% of the pieces found are trailing edge/surface control/wing related pieces.

    And a nose-dive impact contradicts the big nose-gear door piece which shows no compression damage.
    The nose -gear doors would have imploded into the fuselage and shattered in little fragments beyond recognition imo.

    Another argument against a (high speed) nose-dive impact is imo the almost intact shape of the monitor mounting and the not that badly deformed closet panel which also shows no compression damage on the honeycomb (as far as I can see) and was teared out by a force from behind pushing it from its attachments (clearly visible in the pictures) to the front of the plane.
    In a nose-dive this front-closet panel would have been blown to the aft and through all material behind it. Imo no way it could have survived the way it did this way.

    To me this is all fairly obvious it had to be a ditch-like event.
    But ofcourse I can not prove it either.

  39. @TBill

    To add something I found specifically intriguing about the video besides the more or less succesfull ditch on a rather rough ocean surface with leaving little floating debris:

    This pilot chose deliberately and wisely ofcourse to wait with a ditch attempt till the brake of daylight.
    And he deliberately burned up his fuel to prevent fire as much as possible during the ditch.

    Both circumstances happened to be the same with MH370: ‘çrashing’ at the break of day and without fuel left.

  40. @Ge Rijn
    Yes that is interesting. I was just testing your interpretation of the interior pieces. I was interested in the cause of the ditch (bad fuel or hardware issue in the engines?).

  41. @Ge Rijn. Paradox. Yes, fair comment.
    However I think they could have come to that conclusion without that detail if they had sufficient information on the appearance of the flaperon spar and whether it was a match.

    I doubt that the ATSB has responsibility for fracture damage assessment generally except as relevant to the search or as requested by the investigators. They may have done this on the flap for all I know and passed the results to Malaysia.

    If satisfied that the flaperon hit it, however that satisfaction was realised, and that the aircraft hit the water within the limits of the new search, going further or disclosing superfluous information would be unnecessary.

    I am not intent on defending the ATSB, only describing why I will not be following that up with them. Any (unlikely) response probably would not help. The incentive might be stronger for you?

    About the nose wheel door. It would be forced into the wheel well if hit from the underside but it could be blown outwards or crushed length-wise in a “nose-dive” impact. In that, need it have imploded into the fuselage? Even if so, why would no evidence of compressive damage rule that out? Mostly their assessments are of the skin.

  42. @David

    I don’t expect the ATSB to answer any more questions on the outboard flap either.
    Maybe those details will appear in the final report. But I doubt official details will appear that will contradict their own assumptions and conclusions they so consequently hold on to;
    a ghost flight after FMT with an unpiloted high speed dive impact now at 35S with 100% certainty. Although it’s clear to many this 35S cannot be right. And although imo (and others) a high speed dive impact and unpiloted flight after FMT cannot be the case either. I’m afraid they will keep defending their assumptions till kingdom come without ever releasing possibly conflicting details and never allowing independent investigation.

    Without a detailed (independent) forensic report we can discuss the debris-damage also till kingdom come without ever being able to conclude something definite.
    To me it’s obvious but hopefully someday soon prove will confirm what happened.
    In this regard I expect more from the French in the end with a truly independent detailed forensic report on the flaperon.

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