Gatwick ATC
ZOOMER
Been there; done that, am old stick and yoker.
The principle feeling on noise is that those that should be exposed to noise are those who have purchased properties very close to the airport OR under the extended centreline in each direction. Those property prices would have reflected the noise issue.
However, NATS and GAL are now directing both arrivals and departures over new flight paths or a variation on flight paths that introduce serious noise to people who have purchased properties well away from the airport for peace and quiet or as the scientists call it, tranquility. The base db at these locations is about 35-42 db and when the aircraft pass over this can rise as high as 85 db - yes 85 db (I have a calibrated noise monitor). Around Heathrow for example the base db is frequently a constant 65db and on the approach to LHR from the east it is about 65 even 15 miles from the threshold.
It is perfectly possible to plan CDAs that keep noise to the minimum and departures and arrivals that stay on or arrive at the Gatwick extended centre line until at least 7000 feet on take off and above 7000 on arrivals; well below LHR traffic. Arrival merge points should ALL be located over the Channel.
I am sure I do not have to remind you that noise amplitude measured in db is a logarithmic scale. Thus the amplitude of 90db is 10,000 times the amplitude of 30db. It can be horrendous.
As far as autonomous navigation is concerned I have a friend who is even now working on the system for the next range of aircraft.