There are probably a handful of incidences like this, and statistically several where this was the truth but we have no way of ever knowing (e.g. MH370). I'm n

There are probably a handful of incidences like this, and statistically several where this was the truth but we have no way of ever knowing (e.g. MH370). I'm not sure how it could get any worse than this? At the end of the day you will never have a system that will protect you against a homicidal pilot. The closest you can get is requiring two pilots in the cockpit at all times, but if the bigger and stronger of the two wants to kill everyone anyway, there's little stopping them from just trying to kill the other pilot first while the door is locked.