1. Transparent bulletproof plastic or glass door? Why not make the cockpit door transparent so passengers and stewardesses can look into the cockpit?
2. Privacy: A curtain could be installed on the OUTSIDE of the door so that a stewardess can open the curtain to see what is going inside the cockpit.
3. Cam Camera: How about a cam camera in the cockpit? They make such cameras so small that they would hardly be noticed.
4. Cam Camera in passenger area: Also, how about cam cameras in several places in the PASSENGER area, and one especially aimed at cockpit area.
Those suggestions make WAY too much sense. What have you been drinking tonight?
Cameras wouldn’t prevent this. Always having a second person in the cockpit would.
How about just doing a better job of screening the damn pilots in the first place?