That "cannister" has my curiosity spiked. I found a picture at the link below, that shows a soldier pushing in on what appears to be a plunger coming out of the can, facing forward. There are also pictures of the missiles. They are nearly as long as the tube. Definitely a close call for Israel aircraft.
http://www.army.fr.pl/uzbr/sa7.phpSome sort of thermal battery, I believe.
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