Although multi-standard systems are safer than single-standard , one can presume that in the event of a "warm" conflict eg. Ukraine, electronic warfare would make civiilan navigation systems the first casualty.
Whether at some point during a "warm" conflict some clever and deniable kid in Maryland will propose making team red's presidential aircraft or even a tourist craft land 100 feet under the tarmac is a different question; I am sure that neither Boeing nor Airbus like the idea, as once this bell has been rung it can never again be unrung.
Another good reason for having two pairs of trained Mark I eyeballs sitting at the pointy end of the aircraft instead of Roby McRobot.
Last edited by edmundronald; 19th Jun 2016 at 12:48.