Also I would imagine they have undercover people too in the cabins.
In the worst case scenario they might hurt some people in the cabin, but they ain't taking the controls...
Armed guards are fine, but uniformed guards on airlines would not. If they know who has the guns, they can just kill that guy first. If they don't know who is who, that is a whole different matter.
What about that Egypt Air flight? Everyone keeps saying it was a suicide crash of a commercial airliner.
What happens if they get a mole through things and the actual pilot is the guy who wants to hijack the plane? He could shoot the co-pilot then have his way.
Without guns, they could at least start "rasslin' " over the controls.
Come on this is silly. If the pilot is going to crash the plane you are screwed. It makes no difference if he has a gun or not. What does it take to steer the plane into the airport instead of the runway if the pilot really wanted to do that??