Aeronautics, Commercial -- 12 Security measures 6 Aeronautics -- 5 Terrorism -- 4 Law and legislation 3 Prevention 3 Security measures -- 3 more ... Airports -- 2 Evaluation. -- 2 Government policy -- 2 Hijacking of aircraft 2 Hijacking of aircraft -- 2 Lockerbi -- 2 Political aspects 2 Prevention. -- 2 Terrorism 2 Terrorists -- 2 War on Terrorism, 2001-2009 2 Accidents 1 Aeronautical engineers -- 1 Aeronautical engineers -- 1 Aeronautics 1 Aeronautics -- 1 Aeronautics, Military -- 1 Aeronautics, commercial -- 1 Air travel -- 1 Airlines -- 1 Airlines, International -- 1 Airspace (International law) 1 Congresses 1 less ...