Moves to replace conventional air-traffic infrastructure - at present reliant on slow and inaccurate radar and voice comms - with modern satnav and digital networking tech are reportedly "on the right track".
Present-day air traffic is handled primarily by ground controllers using radar, either primary (where the pulse from the transmitter bounces back from the aircraft's skin) or nowadays more commonly secondary (where a transponder on the aircraft sends out a signal in response to the ground radar). In either case, the controller's picture updates only as rapidly as the radar antenna can spin, generally every six seconds or so, and the information - particularly the bearing, as opposed to the range - isn't very accurate.
A jet can fly a mile in six seconds, and the radar blips are far from precise to begin with. Furthermore, instructions and messages are transmitted to and from planes very largely by voice at the moment, leading to very time-consuming comms and high error rates.
All this means that large margins of safety must be maintained, sharply limiting the number of aircraft that can move through a given amount of airspace in a given time. With green/nimby pressure against new runways and airports intense - despite the fact that aircraft may well be greener than surface transportation overall - there's a pressing need to make air-traffic control more efficient and reliable.
That's the idea behind the US Federal Aviation Administration (FAA) "NextGen" plans, which would see the radars in large part replaced by modern location tech such as onboard satnav, and inefficient voice chitchat mostly superseded by digital networking. Precursor schemes such as Automatic Dependent Surveillance-Broadcast (ADS-B), which is underway now, offer a picture updated every second and accuracies inside 50m. Better still, they can make pilots independent of ground control - which is by no means always available - by offering them a clear picture of all the aircraft in the sky around them.
As most Reg readers will be well aware, the cost of NextGen equipment could be insignificant in the context of aviation - any modern smartphone already contains hardware capable of the job.
So the potential's there to move many more aircraft through the sky, faster and more safely - and even to get much more use out of existing runways. Existing Instrument Landing Systems have now reached the point where they can bring a plane down automatically onto a runway in the thickest fog - but the rules mean that planes must still be spaced further apart in low visibility, so that fog still causes chaos at airports. New technologies, using satnav and other locating means, could not only more-or-less put a stop to weather problems, but potentially get more planes down safely in a given time and so obviate the need for more runways. Alternatively, perhaps, they could be used to cut down on night flights.