London's Docklands Light Railway has been driverless since it opened in 1987 and in 2013 carried 101 Million people, its accident rate is way way less than rest of London Underground with drivers attached.
UK's Rail Network uses GPS to decide what door needs to be opened and at which station because simply drivers couldn't cope with the sheer variety of station platforms sizes and door which need opening. There is a manual facility in event GPS goes down but rarely used.
I see Pilotless airlines within 20 years and also believe after initial scepticism they will be accepted.
There is the weather issue but believe that Fuel use will allow airlines to slow and wait outside of weather cells with fuel economy better than current position and closer to other airlines also waiting.
It just has an inevitability about it where computers do the work and humans become drones always at leisure.