As TCS pointed out "A pilot cannot have a 3-inch knife but the crash axe that is in every cockpit is OK?" not only is there one in the Cockpit but on most of the A/C I work on there is also one in the Cabin, not to mention a number of Fire Extingishers (BCF in the eyes hurts and can disable), Plastic trim being snapped off is just as sharp as a 3" Knife if not longer.