The warhead is surrounded by hundreds of steel ball-bearings. The proximity fuse detonates the warhead before it hits the target. The steel ball bearings are what do the damage, so if you examine one of these you might find the bottom of the fuselage and wings peppered with many small holes.
Trust me, the second and third generation shoulder-fired SAMs rarely miss. They can differentiate between a jet exhaust and the flare the pilot dropped to try and fool the missile. You can't climb into the Sun and then roll out to send it climbing vertically past you. They're too smart for that. They're always looking for the "second hottest" source.
That's why we're now sweating bullets because of the SAMs that were sent to Libya and have simply vanished. Any jihad monkey with half a brain and a basic knowledge of English can take down an airliner.
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