I'm curious -- how do they determine where to insert the stinger? Obviously they don't want to injure anyone and there are probably areas of the fuselage (hydraulic & fuel lines, etc) better left alone. Additionally I should think there are areas of a fuselage (attic area of 747 for example) that are less than ideal for fire suppression or rescue purposes.
Note that there are stinger holes in the fuselage side and crown areas
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