What ricochet damage can reveal on the location of the warhead

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There are numerous images showing damage of MH17 caused by shrapnel. We see holes but there are also scratches.

Some of these scratches are caused by what is called ‘ricochet’. Ricochet is a rebound, bounce or skip off a surface, particularly in the case of a projectile.

Could ricochet damage tell us something about the location where the BUK missile exploded?

This post will not provide an answer. The purpose of this post is to encourage research and discussion. My personal believe is that the location of the missile calculated by NLR and TNO is too high.

The angle of which BUK fragments are starting to ricochet depends on many factors.

Accouding to Almaz Antey, the striking elements of the Buk 9M38M1 missile do not ricochet at angles greater than 30 degrees on the aircraft’s aluminium surface. (source)

There are ricochet indications on both the cockpit roof as on the lefthand side of the fuselage.

Dutch Safety Board did not use all parts of the cockpit roof for the analyse of where the missile exploded. Some of these parts were found when the final DSB report was in draft status. However there are a couple of photos available of these roofparts. On the photo below these are indicated by numbers 1,2 and 3.

This post has photos of the cockpit roof as well.

Russian website mh17.webtalk.ru has some interesting photos and information on ricochet and angles of penetration. Google Translate is unable to make any sense of what is written there. Maybe someone can write an english translation?

This website has a lot of information as well including many images.

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54 Comments on What ricochet damage can reveal on the location of the warhead

  1. Mh17.Webtalk.ru link is not opening

  2. Wind Tunnel Man // December 29, 2015 at 6:26 pm // Reply

    It’s very important that one considers the forward movement of the aircraft when analyzing any of the impact marks. When taking into account the average speed of the shrapnel and the constant speed of the aircraft over longer range distances any impact marks or penetrations will be significantly further aft than one would see on a static target. Hence any calculations regarding strike angles must allow for that displacement if one wishes to use a graphic “stringing” method to determine the orientation and position of the missile at the moment of detonation.

    • You said that before and are now repeating the same error.
      I did try to show that what you are talking about only shows your lack of technical education. You have refused to do a bit of extra work and draw me a picture, so that I could pinpoint your mistakes.

      • Wind Tunnel Man // December 29, 2015 at 11:53 pm // Reply

        Eugene:

        It’s common sense that if a projectile is traveling toward a moving target then the target would move a certain distance during the period of the projectile’s travel – do we really need a drawing to illustrate that?

        • Your mistake is not in that statement. But in the idea you are trying to support with that statement. Namely that the ricochets marks are not directed towards the location of the explosion. They are. Anybody interested may read the prior conversation here:
          http://www.whathappenedtoflightmh17.com/what-almaz-antey-presented-on-october-13/#comment-11376
          All the way towards the end of the page (WTM cannot maintan a good thread order, sorry). Most interesting bits are near the end.

          • Wind Tunnel Man // December 30, 2015 at 12:46 am //

            Eugene:

            So a ricochet mark over a longer range perhaps 1 meter aft of where it might be if the aircraft was static would point to the location of the warhead in relation to the aircraft at the moment of detonation? I think not: given the average speed of the shrapnel and the constant speed of the aircraft, which results in my example of a 1 meter further aft impact compared to a static target, then the point of detonation could be mistakenly thought to be 1 meter away from it’s actual position relative to the aircraft.

          • > I think not: given the average speed of the shrapnel and the constant speed of the aircraft, which results in my example of a 1 meter further aft impact compared to a static target, then the point of detonation could be mistakenly thought to be 1 meter away from it’s actual position relative to the aircraft.

            This only shows your lack of relevant education and/or laziness to cover holes in it. Your running around repeating the same wrong statement after being kindly offered to show your mistakes, as long as you can put them in an understandable/formalizable fashion, only shows that you are a stubborn ignorant. Would that be a university exam, you’d get you bad mark and be gone. But on a web-chat board you can carry on repeating the same false statements over and over.

            Anybody else thinks like WTM and cares to try to formally put his idea on a picture? I’ll help you to get a bit smarter by pinpointing the mistakes. Arguing with a man who seem to use a vague language and avoids going into specifics, feels a bit like talking to a politician – not fun.

  3. It is extremely unlikely poor DSB was not in the position to investigate roof plates. They could have been investigated until the last day of publication of their report as an attachment.

    It is extremely unlikely a research institute waits so many months with field research that they first wrote the headlines of their report.

    All this must mean they did not expect or believe to find bowties in the hull of MH17.

    It is nonsense and ridiculous that the plates would fall apart by construction on the metal structure.

    Why not taken the immanent conclusion they did not want to investigate the roof? They must have inspected the pictures of the roof in a very early stage and then suddenly the plates disappeared. Do you think inhabitants used the plates for their sheds?

    There is no single credible aspect in this whole story. And after the report has been pushed through our throat suddenly roof pictures come loose.

    In the rebound it seems someone is promoting 9N314M in a silent action with ‘new’ photos of roof plates. We await the first bowties.

    And in the rebound someone suddenly comes with an unproven EFIS device. But without the physical device we cannot investigate this case. Are we being manipulated to 9M314N without any proof? Is this all a political maneuver by JIT?

    • Wind Tunnel Man // December 29, 2015 at 11:13 pm // Reply

      Basic Dimension:

      It’s like somebody has used a shotgun at short range and blasted away the center of the target. The evidence we are trying to work with is mainly the peripheral damage away from the center of the target. We can certainly study images of that peripheral damage and come to probable conclusions which, in many respects, the DSB failed to do adequately.

      I’ve seen images of MH17 parts piled up in sheds and outdoors near to the crash sites and whether or not all of it has been collected is probably no. One thing is known and that is the Ukrainians did fire artillery and grad rockets into the crash site area and that definitely hampered the initial investigation. The local people of the Donbass did the best they could under the circumstances but I certainly would not wish to accuse them of tampering with or faking evidence.

  4. The website is down (may be because of the load after being linked from here). This happens once in a while with the site. Unfortunately, a message board containing a broad range of information and ideas on the accident is hosted on such a shitty service, with lots of annoying ads.

    The page basically tells that the observed track marks are not consistent with the DSB findings. The explosion happened at the point found by the community, AA and a couple of other investigators, and not where DSB had found it to be.

    The page has a few non-significant mistakes, such as talking about angles on the image as a true representatives of the angles in the world. But overall it is sound.

    My prior pic is very relevant to the subject:
    http://www.whathappenedtoflightmh17.com/wp-content/uploads/2015/10/damage-roof.png

    As well as the previous post by admin:
    http://www.whathappenedtoflightmh17.com/simulation-versus-facts-of-mh17-missile-damage/

    • sotilaspassi // December 30, 2015 at 9:01 am // Reply

      @damage-roof.png

      I pretty much agree on that. There are several indicators that detonation has happened closer to plane nose than how DSB estimated it.
      (A-A detonation was even further away from the right spot)

    • Wind Tunnel Man // December 30, 2015 at 2:13 pm // Reply

      Eugene:

      Thanks for your excellent pic relevant to the subject.

      But you are showing marks on the aircraft caused a fraction of a second after the detonation. If possible please create another diagram showing the position of the aircraft relative to warhead at the moment of detonation, obviously you will have to take into account the constant speed of the aircraft and the average speed of the shrapnel that caused the impact marks. The relative speeds of the aircraft and shrapnel are critical in determining the shrapnel distribution along the longitudinal axis of the aircraft.

      • > But you are showing marks on the aircraft caused a fraction of a second after the detonation. If possible please create another diagram showing the position of the aircraft relative to warhead at the moment of detonation, obviously you will have to take into account the constant speed of the aircraft and the average speed of the shrapnel that caused the impact marks.

        The picture is already drawn in the plan’s reference frame. Whatever happens in the reference frames of Dontesk, Sydney, Moon or Sun has no relevance. But you seem to be missing mental tools to be able to understand that.

        Actually for people like you, who struggle with vector additions and know no notion of reference frames someone has provided an instant-by-instant breakdown of the process of shrapnel leaving marks, which shows in a layman fashion that the ricochet marks/scratches will be directed towards the detonation point regardless of the relative velocity of the missile WRT plane.

        The page is in Russian, and is by the very author referenced by admin in this post. If you fail to understand it just draw your own – the idea should be clear.
        http://mh17.webtalk.ru/viewtopic.php?id=298&p=6#p40739
        (for mobile phones replace “p=6” with “p=10” in the url).

        The original thread referred by admin here also keeps getting updated. The author, meovoto, continues dissecting the report’s fuckup with the detonation point in detail. Btw, meovoto was one of the first people who found the correct detonation point by doing track analysis.

        • meovoto is very reliant on assumption that explosion time is infinitesimly small, which is not true (~200 microseconds vs few milliseconds to reach target) and on constant and uniform speed of shrapnel. In reality we have time variable spread of accelerations for different shrapnel pieces within those firsts 200 microseconds. Variation is in both, magnitude and vector orientation. In case of stationary target, like in A-A test it is not important. In case of up to 1000 m/s relative speed of missile and plane the issue cannot be ignored.

          • During the 200 microseconds the missile travels only a maximum 20 cm WRT the plane. Even if the trajectory is tying knots within such a region this does not affect much – this is just a small area. Knowing the explosion locations with precision of 20 cm is enough for most purposes. Remember that the DSB were off by 2-3 metres – an order of magnitude worse. Therefore I agree with meovoto on that particular issue.

          • Antidyatel // January 6, 2016 at 1:31 am //

            The issue is not the missile speed here. When explosion happens the projections of shrapnel speed on axis parallel and perpendicular to the plane axis will be varying with time, meaning that speed vector will be rotating. For shrapnel flying out in different directions the rate of rotation will be different. The magnitude of this effect is around 0.3-0.5 meter shift for perceived origin of shrapnel flying out in different directions, assuming constant and uniform acceleration for all shrapnel. For actual acceleration distribution and time variance the picture is more complex.
            Although after acceleration the speeds are constant and string tracing can still be used for estimation of explosion point. It is just one should not artificially try to force strings to the same point. Strings should also point to the elongation of the vortex indicating the orientation of the cylindrical charge/ missile orientation. DSB failed to use that important clue.

          • Antidyatel, what you say is correct, but in science when different factors are at play it is important to address the biggest ones first. This principle, seeming obvious, is often missed.

            > Although after acceleration the speeds are constant and string tracing can still be used for estimation of explosion point. It is just one should not artificially try to force strings to the same point.

            meovoto is smart enough to understand that, I assure you. He simply is a bit smarter to dismiss the non-important issue from consideration well knowing the cap on its contribution. And, as you are saying, it is a rather small affect on the detonation point position, much smaller that the errors introduced by the DSB by their bad judgment.

            Secondly, I repeat, the point we obtain by disregarding the initial acceleration is actually more useful for other bits of analysis, such as finding the areas on the skin accessible by shrapnel. The point where the explosion ignitions has started does not matter as much as the point where all the trajectories all seem to emanate from.

          • Antidyatel // January 6, 2016 at 4:18 am //

            “but in science when different factors are at play it is important to address the biggest ones first. This principle, seeming obvious, is often missed.”
            Don’t tell this to climatologists fearmongaring with CO2 based global warming. 😉
            Still, that statement is correct only for linear system. In presence of non-linearity one should be very careful. Eventhough non-linearity was present less than 1/10th of the time it affected the initial condition for the linear part. That is why average speed of shrapnel in stationary test has little relation with average speed in the relative coordinate system of missile and plane. The averaging will be different in both magnitude and direction. And of course the apparent initial point based only on linear part of the regime will be rather broad area, but still smaller than DSB inaccuracy. Plus it should still be useful to estimate missile orientation with sufficient statistics, as the add on factor of relative speed will proportionally elongate the apparent initial point. But we don’t have this sufficient statistics.
            So no excuses for DSB unscientific approach but we should also be careful. In discarding nonlinearity. It is not negligible.

        • Wind Tunnel Man // January 6, 2016 at 1:50 am // Reply

          Eugene:

          You haven’t answered my question: based on the marks on the roof what was the position of the warhead relative to the aircraft at the moment of detonation? You say that those marks indicate a direction towards a theoretical detonation point, would marks much closer to the warhead, i.e. near the nose of the aircraft, also indicate the direction towards your same theoretical detonation point which you based on the marks on the roof? They would not because the aircraft has moved forward to a lesser extent whilst the shrapnel was traveling over the shorter range.

          • WTN, you are missing important means of understanding the physics of the process involved. Your question does not have meaning. You somehow keep thinking that the fact that the plane is moving wrt to Earth is important. But the plane is is also moving wrt to the Moon, centre of our galaxy and a toilet seat in the opera house, all with different speeds.

    • Eugene:

      I have read again all discussion in ‘What Almaz Antey presented on October 13’, because damned I want to understand your point.

      If shrapnel had an orthogonal impact on MH17 we would implant a perpendicular string to the imagined point of detonation. But as Antydiatel already said to clarify WTM’s position, this string must be curved to the real place of detonation, because shrapnel was shot before the plane arrived on that spot. So all angles must be corrected for relative velocity and only then the point of detonation can be estimated. Now I understand this as common sense, other than that I had not gotten around to. Please Eugene, try to explain yourself so that I can understand this dispute.

      • While Antydiatel’s is in principle is correct, he seems to be lacking a bit of technical level to get the quantitative appreciation of the process.

        Yes the shrapnel trajectories in the reference frame of plane will be curved. But it’s easy to understand how they’ll be curved without doing any simulation (I was quite amused by him doing that). There will be essentially two regions on the trajectories: acceleration by the blast and the deceleration by drag.

        The region of the acceleration will be small – may be around 2-3 radii of the warhead. The curvature there will be significant but confined within a small region. So this part of does not really affect the detonation point determination. Furthermore, for most purposes the virtual detonation point – where the lines meet – is more important than the real one (for example of we want to see the reachable areas on the plane body the virtual explosion location is needed).

        The rest of the trajectory is curved by the deceleration due to air drag. But this curving will be minuscule – below 0.1 degrees over a 5 metre long trajectory. If, instead, we assume that the trajectories are straight the error on the detonation point we introduce by using this assumption will be only a couple of centimetres.

        It is therefore laughable that the DSB dismissed the stringing method, saying that the trajectories are curved and switched instead to orders of magnitude less precise method, of which we know little details.

        I emphasize and repeat, the DSB switched from the good stringing method which would have an error of only a few centimitres for the detonation point to their poorly described matching method that has an error of several metres. They switched because the lines that curve by less than 0.1 degree are not straight, in their view. From the scientific point of view their judgment is just appalling.

        In reality though, they switched from the good method to the bad method because the good method would give the result that would not play well with their political agenda.

        • My main focus was on the spread not so much on detonation point. In assumption of constant acceleration for all shrapnel pieces the shift in detonation point will be around half a meter. However, the assumption of constant and uniform acceleration for all pieces in the first 200 microseconds of explosion is very simplistic. Only approximately valid for relatively narrow spread angle originating frombthe middle of the cylindrical explosive. That portion has obliterated the fuselage for any holes to be used for string experiment. The available holes are from shrapnel originating from edges of the charge. The varying and non-spherical shape of shrapnel will also add variation on the direction of the acceleration vector.
          The length of the charge is already 0.5 meters adding to inaccuracy. Also I was doing simplified calculations assuming that missile and plane are going in parallel courses. And finally you have a curvature of fuselage.
          Drag can really be ignored for any practical purposes.
          With all these the string method can work but one should not force the strings to match at one point. But strings should come within the cube of 1-2 meters side. The distribution should actually be ellipsoid elongated along missile direction. So I agree that string method will be quite informative.

          • Wind Tunnel Man // January 6, 2016 at 5:58 pm //

            Antidyatel: You might find this interesting where a “lead angle” is explained:

            http://www.gun-blog.com/2010/08/moving-targets-and-lead.html

            And you may agree that a projectile’s actual path when engaging a moving target can only be determined when a lead angle is established – the exception being when the target is moving on the same path as the projectile either directly toward or directly away from the point of the projectile’s source.

            The lead angle will equate to the distance traveled by the target during the period of the projectile’s travel between it’s source and hitting the target. Numerous punctures and grazing marks can be seen on the recovered parts of MH17’s outer surfaces and each puncture or grazing mark must be treated as an individual target due to the nature of the alleged fragmentation cloud.

        • Eugene:

          Thanks for your explanation which I only just found. I learned a lot of your discussion with Antidyatel and Brendan and will soon try to summarize the matter.

  5. Wind Tunnel Man // December 30, 2015 at 3:38 pm // Reply

    The target was moving into an expanding fragmentation cloud and it might be unhelpful if one chooses to use a static model of the target. A-A simulated the movement of the target by changing the orientation and position of the missile in their static test.

    • sotilaspassi // December 31, 2015 at 8:20 am // Reply

      thinking out loud …
      Shrapnel speed sideways decreases rapidly from initial 2400m/s.
      Small particle & pressure wave speed sideways decrease rapidly from initial 8000m/s.
      Pressure wave change small&light particle track around the plane surface.
      Target moves in solid speed vs the exploding warhead (~250+700m/s).
      Particle and shrapnel paths are therefore indeed curved etc.

      On nearest plane surface pieces (1-2m from detonation) I imagine pressure wave starts to deform the aluminium before shrapnel penetrate the metal. 2..4m from detonation, pressure wave and shrapnel affect target simultaneously. 4…7m from detonation heavy shrapnel hits the plane long before pressure wave or small particles/metaldust.
      Secondary shrapnel cone (the forward part of the warhead and missile) fly in less curved path.

      +a note: A-A detonation near the IL cockpit, shrapnel was not in same angle as in real life when warhead detonated (shrapnel punctures look different) + no curved flight paths of the shrapnel happened + shrapnel had less speed/energy vs target (vs real life MH17 hit) + detonation was too far from cockpit and therefore the pressure wave effect is smaller (+they got less “ricochet” scratches from small particles)

      • Wind Tunnel Man // December 31, 2015 at 12:48 pm // Reply

        sotilaspassi:

        Indeed blast effects should be taken into account: there was considerable dishing (concave distortions) of the aircraft’s skin between main frames and stringers on the aft cockpit roof sections. Without such dishing it’s possible shrapnel would have ricocheted away rather than penetrated. A-A state that a minimum angle of 30 degrees is required for penetration and it’s possible that due to dishing in some places that angle was just exceeded.

  6. Just a note most if not all of you are misusing the term Shrapnel Shrapnel are balls or material suspended in a resin matrix then propelled out of the front of the shell without rupturing the casing These balls continue onward to the target, spreading out in a cone-shaped pattern..like a shot gun This is not what happened here as being discussed ( i did not read every contribution The missile being spoken about here is a fragmentation weapon containing over 8k of preformed objects over 2.6k or thereabouts Bow tie and the rest square Withe the explosion these “disperse” randomly It is notable only 3 have been retrieved. The missile of any of the “BUK” series are designed to normally detonate above the target. In the case of this 777 fuselage it is unlikely I think there would be ricochet as such given that the Fuselage in aluminum The possibility of ricochet in this case in unlikely due to the comparatively soft skin Surface is one of the reasons for the common firearms safety rule “Never shoot at a flat, hard surface.” The angle of fragment departure, both vertically and horizontally, is difficult to calculate or predict and one can only assume the spread unless done with a live experiment which AA have done. I basically just jumped in to clear up the misuse of the shrapnel terminology

    • Davie Macdonald:

      You said:

      [Shrapnel are balls or material suspended in a resin matrix then propelled out of the front of the shell without rupturing the casing]

      We know matrix is classified into three groups: Polymer matrix, metal matrix and ceramic matrix. And these resin comes under soft polymer matrix composites. Will this resin matrix let shrapnel rotate or will it translate? If translated perfect butterflies in the hull are to be expected on 3 meter within 0.0015 seconds.

      You said:

      [The angle of fragment departure, both vertically and horizontally, is difficult to calculate or predict and one can only assume the spread unless done with a live experiment which AA have done.]

      A-A says shrapnel will not ricochet with angles greater than 30 degrees and this is what A-A predicts, a random blur:

      http://tinyurl.com/za4g47a

      But we also know the angle will be perpendicular to the trajectory of the missile so the spread on the surface normal rectangle of the hull can be predicted exactly:

      http://tinyurl.com/npx2ql4
      http://tinyurl.com/qd6fyj9
      http://tinyurl.com/z7v5gg8

      It can be determined exactly how many bowties, fillers and squares are to be expected on this surface normal area:

      To the left of this rectangle we expect to see:

      Bowties = .14 x .32 x 1870 = 84
      Fillers = .14 x .32 x 1870 = 84

      To the right:

      Squares = .14 x .68 x 4100 = 390
      Bowties = .14 x .68 x 1870 = 178
      Fillers = .14 x .68 x 1870 = 178

      We definitely can expect 84 + 178 = 262 butterflies in our 50 degrees segment and there are no excuses.

      As you might know DSB also thinks the pattern on the warhead will be replicated exactly on the target. What is your opinion?

      http://tinyurl.com/oxxy56l

      For this replication on the hull it does not matter if shrapnel translates or rotates.

      You said:

      [Shrapnel are balls or material suspended in a resin matrix then propelled out of the front of the shell without rupturing the casing.]

      On this blog we have a dispute if shrapnel translates or rotates after the blast, what depends on the resistance of the casing, the uniformity of the blast and its echo on the other side of the casing. What is your opinion?

      This is a viewpoint on this site:

      [However, the uniformity of the detonation front is far not sufficient to push the SEs[Striking Elements] in a parallel fashion. So they *do* spin. But there is a stronger reason for why they spin. The warhead wall is made out of a strong load-bearing compound. When the explosion shock shatters the wall, the process is quite chaotic. As a result the SEs not only start spinning but their velocities also get perturbed. That’s why we don’t see a regular pattern of holes on the targets (though some regularity is still present).]

      If only translating there must be seen a lot of perfect ‘butterflies’ in the hull of MH17, what seems not the case:

      http://tinyurl.com/jxplhkv

    • Davie, thanks for clarification. People here do often realise that their use of terminology is quite loose. What is the best term to collectively call the blast products such as fragments and the bits of the missile body? It is often impossible to tell whether a hole was made by one or the other, so we need a collective term for hard flying objects.

      > The possibility of ricochet in this case in unlikely due to the comparatively soft skin.
      Unless the incident angle is almost zero – a grazing trajectory.

      I pointed this out before, but you haven’t joined the site then. It’s worth repeating: the higher the speed of the projectile the more well-defined the resulting hole edge/boundary. For very fast hitting speeds the holes will look like they’ve been burned through, without much deformation of the target.

      Examples:
      a shaped charge holes: http://s00.yaplakal.com/pics/pics_preview/1/2/6/582621.jpg
      http://www.apacheclips.com/files/0ae13939d19a.jpg
      the bow-tie holes on the Il-86: http://savepic.su/6411148.jpg

      On the other hand, a lower hit speed will result in more bent and torn edges. Examples:
      bullet holes:
      http://www.whathappenedtoflightmh17.com/wp-content/uploads/2014/09/bullets.png
      http://img12.deviantart.net/3940/i/2012/108/c/3/bullet_hole_by_roverjunkie-d4wmfr3.jpg
      http://www.milcentric.com/wp-content/uploads/2012/12/Bullet-Hole-Ring-1.jpg
      The alleged right hand side exit hole on mh17 (that no-one knows where it is on the plane body): http://www.whathappenedtoflightmh17.com/wp-content/uploads/2015/10/exitdamage.png
      or entry holes on mh17: https://a.disquscdn.com/uploads/mediaembed/images/1189/8709/original.jpg

      The physical reason for this effect is the following: on a high hitting speed the interaction time of a projectile and a target is smaller than on a slow hitting speed, allowing less target material to get involved in the process. Therefore on high speeds there will be less bending and tearing, and the shape of the hole will match the the shape of the projectile better. On a slow speed, on the other hand, the elastic propagation will have an opportunity to distribute the energy wider (i.e. the phonons will bounce off more and reach further, for you physicists out there) and thus a greater area of the target will participate in the interaction.

      Here is an alternative explanation: on a higher speed the collision forces are higher. For extremely high collision forces the inertial properties of the material become more important than the elastic properties. This is indeed the case, as a penetration of a shaped charge jet into an armour is often modelled as a penetration of a fluid jet into a fluid target (=ignoring any elastic properties/intrinsic strength), giving sufficiently good results. On such speeds the strength of an armour becomes almost irrelevant (for some hard ceramics it is not fully the case though), and the only thing that matters is the density. That’s why Abrams tanks sometimes use depleted uranium armour and depleted uranium projectiles.

      Davie, if you are a specialist in the field of ballistics or related, could you tell your opinion on my observation that the holes on Il-86 look like they have been made by higher speed fragments than the holes on mh17? AA actually voiced their finding that on Il-86 there were almost no ricochets, just as should be for very high hitting speeds. But on MH17 we notice more ricochets, and the hole edges are more bent and torn, often looking crown-like. (Leaving aside the issue that there are plenty of bowtie shaped holes on Il-86, and none on Mh17)

      Compare
      Il-86:
      http://cdn.tvc.ru/pictures/o/185/319.jpg
      https://pbs.twimg.com/media/CRXKtJ8U8AA65x5.jpg:large
      http://kr.sputniknews.com/images/70/86/708667.jpg
      http://savepic.su/6411148.jpg
      https://www.metabunk.org/attachments/83b107d1ce402bf18ad1b663a0cd8269-png.15581 (not exactly on Il-86, but by a Buk)

      Mh17:
      https://niqnaq.files.wordpress.com/2014/07/14769648553_beae8c1a94_o.jpg

      • Eugene:

        Holes on IL-86 must be made by lower speed of fragments than the holes on MH17, since relative velocity between plane and missile must be added. Also bent and torn edges on MH17 must be partly caused by the changed angle of the sum vector of frac speed and missile speed.

        So, even if bowties themselves are positioned perpendicular on the hull they still experience additional lateral forces to acute angles.

        Consequently, even though speeds are greater in case of MH17 it still looks as if the elastic propagation has more opportunity to distribute the energy wider than with IL-86, what is not the case:

        http://tinyurl.com/ogsw8pk

        • Guys. Elastic waves in aluminium is basically speed of sound. By the time fragment with speed above 3000 m/s goes through less than 2 mm Al skin, the sound will travel less than 4 mm. Plus it will propagate along the plane and still need to convert elastic deformation into plastic ones. I don’t understand why do we consider that here. For collision of two bodies we can assume that mass of Al section is much smaller than mass of the fragment. At high-speedsthis assumption is definitely true. There will be practically ellastic collision. Both the fragment and matching section of skin will fly in one direction.
          Based on abstract of this paper “https://www.researchgate.net/publication/223629536_Plastic_Deformation_and_Performation_of_Thin_Plates_Resulting_from_Projectile_Impact”
          Even 300 m/s will cause full perforation. So I don’t think there should be any plasticity deformed holes.

          • > Elastic waves in aluminium is basically speed of sound. By the time fragment with speed above 3000 m/s goes through less than 2 mm Al skin, the sound will travel less than 4 mm.

            That’s allright.

            > So I don’t think there should be any plasticity deformed holes.

            I guess you need to better look at the pictures:
            http://savepic.ru/8263280.jpg

          • Antidyatel // January 15, 2016 at 5:29 pm //

            I’ve seen these pictures. The point is that I looked at the problem from physics perspective. Of course I use simplified assumptions but it seems that in case of BUK explosion and fragment speeds are as high as specified, then such deformations should not take place. I wish someone can explain the mechanics that allow such deformation in case close proximity BUK missile explosion.

      • The reason for the cleaner holes in the Il-86 is not the speed of the fragments. It’s the fact that the fragments struck at a much greater angle to the surface than those that struck MH17.

        AA’s Il-86 experiment was based on the detonation location that the DSB estimated. That was the wrong location and therefore produced wrong angles of impact. Being further away from the aircraft, the fragments from there struck the skin more from a perpendicular than a parallel direction.

        A huge amount of evidence shows that the warhead that destroyed MH17 detonated much closer to the cockpit than the location that the DSB calculated, but the DSB ignored that evidence in their report. Because the warhead actually detonated so close to the cockpit and because the aircraft surface is so curved around that area, very many fragments struck almost parallel to the surface. The only exception to that would be some small areas very close to MH17’s front left window, but those parts were never found, presumably because they were so badly damaged and were blown apart by the blast.

        That also explains the lack of bowtie shaped holes in the MH17 wreckage. It’s easier to punch a clean shape through a surface when striking it almost perpendicularily, as happened in AA’s experiments.

        • Brendon, thanks for commenting.

          > Being further away from the aircraft, the fragments from there struck the skin more from a perpendicular than a parallel direction.

          Firstly. I specifically picked the point on the cockpit near the window where the fragments struck almost perpendicularly. And again, for very high speeds the incident angle is not that important: the fragments will cut though aluminium like through butter.

          Secondly, you seem to have got a bit confused, so that you’ve the logic inverted. It is for a closer detonation point more fragments will be hitting “perpendicularly” than for a distant point-source. You’ve got it the other way around. Just consider two extreme cases: a point source of rays far away from a spherical target and a point source almost on the surface of the spherical target (sphere is taken to simplify the general idea, for other shapes the argument still holds) – more rays emanating from the source will be hitting “perpendicularly” for a close location. So if AA put the bomb closer, at the right location, there would be even more “perpendicular” holes.

          > A huge amount of evidence shows that the warhead that destroyed MH17 detonated much closer to the cockpit than the location that the DSB calculated.

          I agree with you. The DSB had to move away the detonation point because the right location would give fragment density too high for a Buk (by around three times).

          To recap:
          -Detonation point wrong (to fit the Buk theory).
          -No bowtie holes observed on the skin, but three bowties planted.
          -Fragments hit the cockpit at a much lower speed that that of a Buk.

          PS: waiting for opinion of people familiar with explosion damages/ballistics…

          • Hi Eugene,
            “Firstly. I specifically picked the point on the cockpit near the window where the fragments struck almost perpendicularly.”

            Sorry, I’m not sure what point on the cockpit that is. Is it on the Il-86 or MH17? Please give a link to the photo of the part you’re referring to.

            “for very high speeds the incident angle is not that important: the fragments will cut though aluminium like through butter.”

            That’s true only if the speed is extremely high, but we don’t know if the fragments striking MH17 had enough speed to cut clean through it at almost any angle. And the angles of impact in the Il-86 experiment are much more limited and do not represent what happened to MH17, because of the different distance.

            At lower speeds the angle does affect how clean the hole’s boundary is. If the angle is almost parallel to the surface, the component of its velocity perpendicular to the surface is relatively small. As you said earlier, “the higher the speed of the projectile the more well-defined the resulting hole edge/boundary.” Replace the word “speed” with “velocity component perpendicular to the surface” and you should see what I mean.

            Regarding the effect of the distance of the detonation on the incident angle, I’m not saying that the detonation occurred just above the surface. At that location, the surface would look flat, just as the earth looks flat to anyone who has not been in outer space. Move further out and the surface looks more curved.

            Yes, many of the projectiles fired from that location will hit an apparently flat area “perpendicularly”. However, as I said in the case of MH17, parts of that area were not found because they were probably blown apart by the blast.

          • Eugene:

            [To recap:
            -Detonation point wrong (to fit the Buk theory).
            -No bowtie holes observed on the skin, but three bowties planted.
            -Fragments hit the cockpit at a much lower speed that that of a Buk.
            PS: waiting for opinion of people familiar with explosion damages/ballistics]

            I am not familiar with explosion damages/ballistics but it all seems not that difficult. Formulas are a form of human thinking, what means in the end they always must be transformed into intuitively felt truth. So, if I don’t understand, your formulas must be wrong.

            The fact no bowtie holes were found in the hull or windshield does not mean bowties are planted. It only means in a criminal investigation bowties unproven came through the hull or windshield.

            But in a normal accident they would have been accepted as proof of 9N314M. Consequently 9N314M cannot be confirmed along these lines. And remember, fillers also do not meet this conditional probability. BTW, it is remarkable fillers in the windshields were not investigated.

            This is a very good and inspiring analysis:

            [The physical reason for this effect is the following: on a high hitting speed the interaction time of a projectile and a target is smaller than on a slow hitting speed, allowing less target material to get involved in the process. Therefore on high speeds there will be less bending and tearing, and the shape of the hole will match the the shape of the projectile better. On a slow speed, on the other hand, the elastic propagation will have an opportunity to distribute the energy wider (i.e. the phonons will bounce off more and reach further, for you physicists out there) and thus a greater area of the target will participate in the interaction.]

            But now a complete mathematical model must be built which shows BUK has been unable to make these holes. The distance to the detonation point must be variable. Hence, it must be shown the speed of BUK fragments is too high to cause this bent and torn holes:

            http://tinyurl.com/jxplhkv

          • > Sorry, I’m not sure what point on the cockpit that is. Is it on the Il-86 or MH17? Please give a link to the photo of the part you’re referring to.

            These http://savepic.ru/8263280.jpg

            > At lower speeds the angle does affect how clean the hole’s boundary is.

            The bowties all fly with almost the same speed. In the AA test there are cleanly-identifiable bowtie holes from hits at reasonably shallow angles:

            https://html1-f.scribdassets.com/4y9tudaghs4sj3w9/images/61-d205bc26e8.jpg

            > in the case of MH17, parts of that area were not found because they were probably blown apart by the blast

            The middle-right window was closest to the blast and yet enough surface of it was recovered
            http://www.whathappenedtoflightmh17.com/wp-content/uploads/2015/10/BDorg-1024×839.png

            It is amazing how many clean bowtie holes are visible on Il-86. Unfortunately AA have not released other pictures than the slides:
            https://www.scribd.com/doc/284722224/Slideshow-van-Almaz-Antey

          • Hi Brendan. The above was a reply to your comment. I hope you get past my trivial mistakes (leftright).

          • Came across this nice picture:
            http://uploads.ru/v5kor.jpg
            Do you agree that the density of holes on Il-86 and 777 look roughly the same? To me, if anything, Il-86 might have even a slightly higher density of holes.

            But a correct explosion point is located at least twice as close a distance away from the window. So if AA had placed the missile at the correct explosion point the hole density would have been four times higher than on mh17. That’s why the DSB tried so hard to move the point away.

          • Eugene, the surface in that photo under the left window is quite a bit back from, and below, the detonation location estimated by AA, and it curves away from that location. The angle is therefore far from being perpendicular to the direction of the projectiles.

            That part of the cockpit also looks like it has an extra layer of steel, as protection against oncoming objects in the sky, like bird strikes, than the areas further back on the aircraft.

            The surface on the Il-86 with the bow-ties, on the other hand, is facing more in the direction of the different (incorrect) detonation location in the AA experiment. Even though it’s further back than the MH17 part that you showed, the detonation in the experiment is much further out, producing a greater angle to the plane of the surface.

            “The middle-right window was closest to the blast and yet enough surface of it was recovered”.

            Yes there are a lot of holes in that window, which was was almost directly facing the detonation, but it’s made of a number of layers of plastic and glass. Those materials, especially the plastic, will spread out the energy more than a layer of aluminium will. It’s all about elasticity, as discussed earlier. I think that this is supported by the fact that there are no distinct shapes of any type in those holes – not just no bow ties but no spheres, cubes or parallelipipds either.

          • “Do you agree that the density of holes on Il-86 and 777 look roughly the same? To me, if anything, Il-86 might have even a slightly higher density of holes.

            But a correct explosion point is located at least twice as close a distance away from the window. So if AA had placed the missile at the correct explosion point the hole density would have been four times higher than on mh17. That’s why the DSB tried so hard to move the point away.”

            Yes, the density of holes is approximately the same despite the huge difference in the area of damage. The other image you provided shows that too:
            http://cdn.tvc.ru/pictures/o/185/319.jpg

            The DSB and their contractors made that area smaller in their model by artificially creating a narrow beam of fragmentation with a conical shape. However, that narrow beam only increases the fragment density, which cancels out the effect of the greater distance between warhead and aircraft. So there’s still a big discrepancy in hole density between the DSB model and the results of the AA experiment.

          • To be more precise about my last comment, the narrower beam only partly cancels out the effect of the greater distance. That’s because fragment density decreases proportional to the beam width but proportional to the *square* of the distance.

          • Brendan, good comments, thanks.

            > The angle is therefore far from being perpendicular to the direction of the projectiles.

            The bowties in the AA test made clearly identifiable holes even at shallower angles: http://savepic.ru/8338772.png
            AA said that the target specification for the warhead design was that the bowties could penetrate 26 mm of aluminium. Anyway, because without high res images of Il-86 damage it is impossible to reliably compare the characteristic properties of the holes, I am postponing my assertion that the holes on Il-86 look higher speed than the ones on Mh17.

            > The DSB and their contractors made that area smaller in their model by artificially creating a narrow beam of fragmentation with a conical shape.

            Yes, despite the fact that the missile manufacturer had provided them with the correct data they made the bean narrower almost by a half. They did that not only to tweak the simulated hole density, but also for their matching method, whatever it was, to be able to produce the damage strip of a correct width. If, instead, they used a correct value for the beam opening angle then the simulated damaged area would be much wider than the damaged area observed on Mh17.

            That fact was immediately spotted by the web-researchers like us and was complained about by AA. Such a brutal manipulation of data.

            > Yes, the density of holes is approximately the same despite the huge difference in the area of damage. The other image you provided shows that too.

            I don’t know why you’d need to have a technical mindset to notice this gross inconsistency. Why don’t average people pay attention to what you say: “the huge difference in the area of damage”? http://savepic.ru/8334698.png

        • Brendan:

          [The reason for the cleaner holes in the Il-86 is not the speed of the fragments. It’s the fact that the fragments struck at a much greater angle to the surface than those that struck MH17.]

          IMO the reason for more acute angles lie in a dynamic situation where relative velocity between plane and missile influence speed of shrapnel and also the direction of the sum vector. This gives translation of shrapnel on the hull, more acute angles of impact.

          [Being further away from the aircraft, the fragments from there struck the skin more from a perpendicular than a parallel direction.]

          Can you explain why difference in distance of the warhead to the target over just a few meters can change the angle or impact dramatically? Greater distance to the target just may influence the dispersion of shrapnel and maybe give somewhat different angles of impact.

          http://tinyurl.com/q9galdq

          [The only exception to that would be some small areas very close to MH17’s front left window, but those parts were never found, presumably because they were so badly damaged and were blown apart by the blast.]

          No bowties were found in the windshields and no fillers sought:

          http://tinyurl.com/h9kw2lx

          • Basic Dimension, I hope my replies to Eugene explain what I mean about the different angles of impact in MH17 and the Il-86.

            “IMO the reason for more acute angles lie in a dynamic situation where relative velocity between plane and missile influence speed of shrapnel and also the direction of the sum vector. This gives translation of shrapnel on the hull, more acute angles of impact.”

            The motion of the aircraft had some effect on those angles, but not much, since it was travelling about at about one tenth of the speed of the fragments.

            I think that the aircraft velocity is of more significance in its effect on the position of the detonation. It only affects it by a small amount, maybe less than half a metre. However that amount is considerable when you compare it to the distance from the cockpit, which Almaz-Antey calculate at less than 1.6m. I haven’t seen AA’s press conference from the same day as the final DSB report, so I don’t know if they took the aircraft velocity into account.

          • Brendon,

            > I think that the aircraft velocity is of more significance in its effect on the position of the detonation. It only affects it by a small amount, maybe less than half a metre.

            That’s not entirely correct. The position obtained by the stringing method is not directly dependent on the aircraft speed. If the missile exploded near the ISS going at an orbital speed you’d still be able to use the stringing method just as reliably, and get an even more precise result as there is no air drag (although up there you’d need to intersect the lines that are much more “parallel” to each other than on mh17). The affect of the air drag does influence the error of the stringing method (and here is the place where speeds do play a role). But this error can easily be estimated and will be no greater than 2 centimeters.

            I previously tried to explain to those two men, Basic Dimension and Wind Tunnel Man, the concepts of mechanics such as reference frames, to show why the stringing method is appropriate. But they seem to prefer to stick in their reasoning closer to the levels of housewives .

            > I haven’t seen AA’s press conference from the same day as the final DSB report, so I don’t know if they took the aircraft velocity into account.

            They certainly did. They’ve also done a comprehensive search of the additional rotation of the missile to make sure that the static test matches the dynamic test as much as possible (only to came up with the same 16-17 degree additional rotation that can be obtained on a small piece of paper and which I mentioned on this website some time ago).

          • Eugene,
            I don’t believe that simply using the stringing method, without considering the aircraft velocity, will produce an accurate location.

            If the aircraft had been static (imagine that it was hovering instead of flying), all the grazing marks would point to a single spot (if we ignore the length of the warhead).

            But because it was moving, then in order to find an accurate location, aircraft velocity must be subtracted from the velocity of the fragments flying towards the grazing marks. And since the grazing marks at different parts of the 777 were produced at different distances and from different directions relative to the detonation, they’re affected in different ways by the aircraft velocity. As a result, the different grazing marks on the aircraft point to different spots.

            Maybe you think that it simply has to do with whether the detonation location is viewed from the point of view of the aircraft or of the missile, but I think that it’s a bit more complicated than that. It’s hard to explain without graphics but I think there may be some truth in what BD and WTM say.

          • Brendan

            > I don’t believe that simply using the stringing method, without considering the aircraft velocity, will produce an accurate location.

            Then you need to specify with respect to what you need to measure the aircraft velocity? Donetsk, Sydney or the Moon. You’ll get different aircraft velocity when measured wrt to each of those. Which one is right? And if you say you want to measure the plane’s speed wrt to the air, then you’ll also need to answer at what air density (or, alternatively, on what height) you’ll stop measuring speed wrt to the air? Will you still be measuring the aircraft’s speed wrt to the air on the height of the ISS?

            For people like BD and WTM and possibly you, who struggle with vector additions and know no notion of reference frames someone has provided an instant-by-instant breakdown of the process of shrapnel leaving marks, which shows in a layman fashion that the marks will be directed towards the detonation point regardless of the relative velocity of the missile WRT the plane.

            The page is in Russian, but if you fail to understand it just draw your own – the idea should be clear.
            http://mh17.webtalk.ru/viewtopic.php?id=298&p=6#p40739
            (for mobile phones replace “p=6” with “p=10” in the url).

          • Eugene,
            “Then you need to specify with respect to what you need to measure the aircraft velocity? Donetsk, Sydney or the Moon. You’ll get different aircraft velocity when measured wrt to each of those. Which one is right? And if you say you want to measure the plane’s speed wrt to the air, then you’ll also need to answer at what air density (or, alternatively, on what height) you’ll stop measuring speed wrt to the air? Will you still be measuring the aircraft’s speed wrt to the air on the height of the ISS?”

            You seem to misunderstand. I’m not saying anything about drag or air density. I was talking about the effect that the motion of the aircraft and the projectiles relative to one another has on the angle of impact. As long as all velocities are measured relative to the same thing, in the the air or on the ground or wherever, they’ll produce the correct result. Then the velocity of the aircraft can be added by vector addition to that of the projectiles to give the relative velocity.

            I’ve been thinking again about the stringing method, though, and I think now that it may produce an accurate result. What was confusing was the fact that different fragments struck different places at different times, due to the different distances. I thought that the direction of the grazing should have to be adjusted to take account of that.

            I now think that what matters is not the direction of the grazing at the time of impact, but their direction at the time of detonation. That seems paradoxical because impact has not yet happened at the time of detonation.

            That can be explained more easily by thinking about a bullet fired at right angles to the direction of a very fast speeding car, and grazing its roof. The grazing mark will be at an angle, and at the time of impact it will not point at the gunman. However if you imagine rewinding back to to the time that the bullet was fired and if you draw the grazing mark on that image, it will then point towards the gunman. That seems paradoxical because that’s a different position of the car and a different time to when the bullet strikes the roof. It can be seen to produce the correct result, however, if you consider the speeds and distances travelled by the bullet and the car until the time of impact.

            Based on that, a similar argument can be made to show that the angles of impact on MH17 point towards the warhead’s location at the time of detonation. So I believe that the stringing method can find that location correctly.

  7. > Holes on IL-86 must be made by lower speed of fragments than the holes on MH17, since relative velocity between plane and missile must be added

    My point is that the Il-86 holes look higher speed, while they should look (a bit) lower speed, as you say. I am talking purely about the observation.

    And, please, get grip with numbers, at last. The fragment speed in the dynamic case is greater than that of in static test by around mere 6 percent:
    sqrt(2400*2400+(600+250)*(600+250))/2400=1.06
    It’s not worth bringing that static-vs-dynamic argument again.

    • Wind Tunnel Man // January 29, 2016 at 5:40 pm // Reply

      Eugene:

      “It’s not worth bringing that static-vs-dynamic argument again.”

      No, it is significant.

      I fully agree with Brendan when he says ‘I now think that what matters is not the direction of the grazing at the time of impact, but their direction at the time of detonation. That seems paradoxical because impact has not yet happened at the time of detonation.

      That can be explained more easily by thinking about a bullet fired at right angles to the direction of a very fast speeding car, and grazing its roof. The grazing mark will be at an angle, and at the time of impact it will not point at the gunman. However if you imagine rewinding back to to the time that the bullet was fired and if you draw the grazing mark on that image, it will then point towards the gunman.’

      Eugene, if you can imagine a slow motion replay of the aircraft moving into an expanding fragmentation cloud where fragments are traveling at various average speeds then you might realize that any single static representation of this is quite useless. A series of static diagrams representing time after detonation and the relative movements of warhead fragments and the aircraft might however be useful. For this we need to know a hypothetical warhead position and missile orientation relative to the aircraft at the moment of detonation, the nature of the fragmentation spread and the velocity of individual fragments. Any over simplification of this scenario by using a few numbers and perhaps a single static diagram is not helpful.

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