Stun guns are absolutely useless. First of all, you have to nearly touch the guy to zap him. If he has a boxcutter, you are very shortly going to be the newest member of Nicole Brown Simpson's PEZ dispensing team.
And what about the recharge time for the second perp? While you're smiling from your new mouth on your neck from the boxcutter, the second perp finishes you off. Think again!
Tasers aren't any better. Unless you can douse the guy with vodka first, and ignite it turning him into a roast. Don't laugh, a policeman did just that to a guy who they couldn't subdue. Turns out they had just liberally sprayed him with Pepper, whose carrying agent is alcohol...
Most military pilots know about bullets going thru airplanes. Most of the time they don't do anything but make a noise like the sound of a quarter hitting the fuselage. (At least AK-47/Chicom SKS that I've experienced, a much faster round 3500 FPS vs 1200 FPS.)
A nice well oiled, properly cared for automatic will do nicely to send the next perp to enter the cockpit to meet his maker.
They make nice bullets for people like that, hollow point with 30 or 40 BB pellets that explode on impact. I like them a lot, for they will stop a man but will not penetrate wallboard. They're called Magsafe, widely available here in the US of A. I use them at home.
The pilot arming provisions have been agreed to by both the Senate and the US House of Representatives. I'm sure there will be no shortage of volunteers for the course of instruction.
I've taken a good look on the bar on the door of my 757. It's only going to slow them down.
One of my company's airplanes recieved a fighter escort today into Denver, CO. Turns out they didn't answer an ACAR's message. The ACARS was locked up in a Dispatching function. Had there been a NORDO, (No Radio), it probably would have been shot down.
I think the least that you can do is let me fight for my life.