The only completely automatic trains I know of are at the airports for shuttle duty between the main terminal and the outlets. There aren't any freight/pax trucks/cars/planes that are full auto etc.... There has to be human over-sight, for the reasons you stated above. Could it be single-pilot large transport aircraft, I believe so, but it'll be awhile. Plus the general public wouldn't stand for less than 2 pilots up front for a long long time.