Datalink – a long time coming

The idea of sending instructions to an aircraft as data rather than voice communication seems like an obviously good one. It would lessen the chances of a misunderstanding while at the same time freeing up the pilot and controller for other tasks – a two-fold safety advantage.

Yet it may be a surprise to many people that a lot of communication between air traffic control and aircraft is still via two people at either end of a radio, but that’s expected to change in the coming years with the greater use of datalink technology.

The journey to this point has been a long one. Datalink was first used within NATS back in 1999/2000 to enable us to better communicate with traffic over the North Atlantic where there is little or no radar coverage and VHF radio contact is impossible. As a result, around 70% of transatlantic traffic is now datalink enabled. That means we no longer have to respond to communication difficulties by increasing separation distances, something that results in delays and a loss of capacity.

However, oceanic traffic accounts for only 1,200 of the 6,000 or so flights through UK airspace every day. As such, in August this year we completed the roll out of datalink technologies at our two en-route centres at Swanwick and Prestwick, meaning we are now ready to provide air traffic services via datalink to any equipped aircraft anywhere in our airspace.

This has taken a significant investment – including large scale upgrades to existing legacy systems; the training of every en-route controller in the UK; and changes to our central flight data processing system. Installing VHF stations across the UK in some very remote locations was a major engineering challenge and as part of our customer engagement, we also ran three airline workshops, with representation from BA, Virgin, SAS, Thomson, FlyBe, Easyjet and, Monarch amongst others.

To date, equipage levels in domestic airspace are still low – in the tens of aircraft a day – but we’re already starting to see the benefits. There was an example of three aircraft all with call signs ending ‘71’ where the controller elected to use datalink to communicate with one of them to eliminate the potential for any confusion between the pilots.

And while numbers are modest today, aircraft equipage will grow as airlines move to meet a European deadline and as more ground based infrastructure becomes available. Eurocontrol is predicting a 75% equipage rate by the end of 2015, with datalink forming an important technical aspect of achieving the vision of a Single European Sky.

The greater the take-up the greater the benefits for all parties will be.

At NATS, we are trying to reduce our controllers’ workloads and increase their wider understanding of the air traffic environment in the safest way possible. The aim is to cut down on routine tasks to enable them to devote more time to improving the efficiency of the services offered to our customers.

Datalink will definitely play an important role in achieving that aim in the coming years.