In the days of the Cold War, aviators used to be issued a Beretta 9-millimeter pistol in the event they were shot down, but the experience of Somalia--plus the advent of two additional wars in th Middle East--have led Army aviators to carry both their 9-mm plus an M-4 carbine.
Before every flight--much like on your civilian passenger flights--the crew sits down and discusses what to do in case of an emergency. On one flight, I heard one of my fellow pilots say, "If we crash, I have a bag in the back of the aircraft. It has several hundred rounds of ammunition--if you grab no other bag, make sure you grab that one, because we're gonna need it"
Ever the cynic, I chimed in, "I, on the other hand, strapped all of my ammunition to my survival vest. Because I know if I crashed a burning aircraft into the middle of a hostile crowd, I'm not sticking around to dig through the cabin for a backpack. We'll all be too busy running and shooting for our lives."
"Eh, good point"