There's been a lot of ideas mooted about preventing hijackers getting control of the aircraft and I wonder if there is really any sure method. Some expert claims that Sky Marshalls would stand out like sore thumbs among the ordinary passengers. If that is the case then 'jackers don't need to bring weapons on board. They will be there already. The Israeli model is probably the best, which has a combination of steel doors to the cockpit as well as armed guards. Another probability is the installation of an over-ride which could be controlled from the ground allowing the controller to land the aircraft. I suppose that in future pilots must be thought to ignore the fact that passengers and colleagues will be killed in order to bring them out of the cockpit. Not a decision to be taken lightly and will need a special breed of person. But then who know what humans are really capable of. Only look at Switzerland today. The last place on God's earth where it would be assumed someone would go berserk with a gun.