“a heat seeker would have hit an engine not the body of the plane... that’s what they do is seek the hottest heat source, and that was not the fuselage “
A 747’s engines are right there next to the fuselage. Missiles are not terribly accurate at those speeds and it will rarely hit the engine directly. Not to mention, do you know if the missile guidance system is programmed to find center mass between those 4 hot spots and not just strike a single hot spot? (Hint: I know they are.)
is it selectable on all stinger/sidewinder systems? or is it standard? who selects the option or does the missile select which mode it will use? what if there's only one engine?