Not a good idea. If they know that there are guns in the cockpit than those in the cockpit are most probably the first to die..And what about the aircraft and passengers than?
Security should start 1 mile outside the airport, like in Israel and the change that you will ever get a hijacker in the cockpit should be reduced to zero or at least bare the same risk as a triple engine failure on a 747.
I talked to a guy who trains anti-terroris teams. He said : do you really think that you have any change with weapons or pepper spray with a guy who has been training for the last two years in any dirty trick in the book? That guy doesn't need his eyes to kill you...
Lets learn the lessons from El Al. Apart from that: I was hired to be a pilot and not a soldier.
