[frevd]

In summary, there must be mechanisms to de-authorize personal, by means of majority vote. To prevent an attack vector, biometric systems need to be used to verify other authorized personal safely (it might be far fetched, but measuring certain stress hormons might prevent attackers from controlling authorized personal and using them to override controls as well, and likewise, other authorized people must be able to act, e.g. by having controls that cannot be blocked by any means (re voice recorders all over the plane to enable or disable locks etc, again by majority vote)). Does that sound too futuristic? I wouldn't want to board a plane if I cannot be sure that any and all cases are covered.