Original URL: http://www.theregister.co.uk/2009/10/01/nextgen_on_track/

Flying car & roboplane-worthy air traffic digi-net go for 2025

Radar, voice to be replaced by satnav and data

By Lewis Page

Posted in Government, 1st October 2009 10:02 GMT

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the radars in large part replaced by modern location tech such as onboard satnav, and inefficient voice chitchat mostly superseded by digital networking.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.

But what about the robots and flying cars?

If all this is to happen, however, national and international protocols and standards need to work properly. NextGen and its European equivalent, SESAR, need to be compatible. The architectures have to be open so as to allow new technology to be added - for instance the soon-to-appear new Euro-satnav constellation Galileo, or improved networking kit. Security needs to be got right.

Is this happening?

To answer that question, the FAA handed out a five-year, $10m deal in July to a body called the Network Centric Operations Industry Consortium (NCOIC). Under the agreement, the aerospace-IT industry matches the FAA dollar for dollar in monitoring and assessing NextGen kit as it comes on line, identifying problems that need sorting out.

Early indications are apparently positive, with Flight International reporting today that the NCOIC ongoing study says that NextGen is "headed down the right street" and that a 2025 timeframe is realistic.

NextGen/SESAR type technologies are of interest to Reg readers apart from their implications for ordinary aviation, too.

For one thing, a working system along these lines would make life hugely simpler for builders and operators of unmanned aircraft. At the moment, such machines are mostly restricted to operations outside civil regulated airspace, as they are deemed to lack the "sense and avoid" capability offered by human pilots - much though this is often largely notional in the case of high-speed aircraft, especially in poor visibility.

A working location net would tell a robot pilot where all the other aircraft were in terms it could understand, allowing it to operate in congested, tightly-regulated airspace at least as safely as a human pilot does under instrument-flying rules and radar control. Unmanned aircraft would be able to fly in normal airspace, rather than being restricted primarily to operations above far-flung warzones as they are today.

And that in turn has important implications for the field of personal air vehicles - flying cars. In order to be safe in the air, especially crowded airspace above urban areas, such cars would currently need to be flown by very highly-qualified pilots, making them too troublesome to own for most people. This is why more realistic personal-air-vehicle plans have usually assumed a hugely capable autopilot/flight-director system, one so good that it would be pretty much capable of conducting a trip without any human input at all. Such autopilots are already available, but collision avoidance is the one thing they have yet to master.

In the skies of 2025, with working NextGen/SESAR not just available but quite possibly mandatory*, with the traffic system able to handle orders of magnitude more aircraft per cubic mile, one of the toughest obstacles to our long-desired flying cars might finally have disappeared.

Now all we need is the actual cars. ®

*Just as a secondary-radar transponder is more or less required for ordinary aircraft these days, certainly if they want to fly outside quite limited portions of the UK.