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Comment by escapologybb | Hacker News Reader

Can anyone break down how they knew that the missile exploded within a one square metre volume of air, just above and to the front of the plane please?

Do they do it just from the pattern of debris, or do they use other methods as well. I think I got that they can use the microphones in the cockpit to work out the direction the missile fragments came from, but not quite sure on the details.

Thanks in advance!

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They triangulated it using the three microphones I guess. Also I guess you can figure that out by looking at the debris pattern because they seem to have a lot of knowledge about the used rocket.

They did that and they also used string to track back from the impact sites to a rough point in space.

There were actually four microphones - captain, first officer, cockpit and observer (see page 46, Figure 9). Four receivers is sufficient to determine the sound origin at a point in space, with an associated error volume (three receivers only allows you to determine a curve in space).

See https://en.wikipedia.org/wiki/Multilateration

The problem is complicated if we consider that the missile is moving at supersonic speeds (~mach 3 + aircraft speed).

I don't know much about supersonic fluids. For anyone interested in following this up, here is a paper on "Reproduction of Virtual Sound Sources Moving at Supersonic Speeds in Wave Field Synthesis":

http://www.researchgate.net/publication/230702229

They also reconstructed the front section of the plane from the wreckage which indicated where the shrapnel had entered.

I'm interested that the missile effectively missed. Is this the intended method of action, nearby explosion with shrapnel impacts or should the missile have entered the body of the plane in a, militarily speaking, perfect deployment. With such weapons do they choose the point of impact, ie is the cockpit the target, or are the weapons not that "refined".

Intended.

Planes are too fast and too maneuverable. Especially military planes — SAMs weren’t actually designed to down civilians. That’s why missiles have proximity-based detonators, so called “proximity fuze”, to explode at the right moment.

BTW, here’s 8 minutes video about the history of that technology: https://www.youtube.com/watch?v=Kq_Uy5hGazc

Good video, thanks.

Summary of video: USA developed the "VT fuze" proximity fuse used initially in ship based AA fire; improved efficacy rates from 2400 down to 400 rounds needed to down an aircraft. First used over ground at the Battle of the Bulge.

It's really well explain on the video linked by nns https://youtu.be/KDiLEyT9spI?t=624

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