NATS to enable ADS-B transponder functionality for GA community

A trial to enable General Aviation (GA) pilots to use the full ADS-B functionality of their Mode S transponders has been kicked off by NATS, with support from the CAA and AOPA UK

The trial, which began in December 2014, has seen pilots encouraged to connect their transponders to a non-certified GPS receiver in order to start broadcasting their position via ADS-B.

Doing so will allow them to track their aircraft in real-time, while with an additional receiver it will help increase awareness of nearby ADS-B equipped aircraft.

While NATS doesn’t rely on ADS-B to detect aircraft, it believes that encouraging the GA community to use it will deliver additional capabilities in the air and on the ground, and make the UK’s busy airspace even safer and more efficient.

Jonathan Smith, NATS General Aviation Lead, said: “The aim of the trial is for NATS and the GA community to understand whether uncertified GPS positions can be used to deliver real safety benefits. This could be in the form of traffic alerts in the cockpit, enhanced situational awareness or even information being spoken directly into a GA pilot’s headset.”

“In addition, GA pilots will start to become visible on apps like Planefinder and FlightRadar24, which we think is very exciting for the community.”

To take part in the trial a minor aircraft modification must be approved by either the CAA or EASA, or other delegated authority like the Light Aircraft Association or British Microlight Aircraft Association. The CAA is helping to encourage the trial by waiving its minor modification fee for qualifying ‘annex II’ aircraft.

The trial is being run as part of a wider project called ‘EVA’ – Electronic Visibility via ADS-B – where NATS is working in partnership with AOPA UK, Trig Avionics, Funke Avionics Gmbh and Eurocontrol, to validate the use of ADS-B by the GA community. The project is co-funded by the SESAR Joint Undertaking.

A second element of the trial will see the introduction of a new prototype device called the Low Power ADS-B Transceiver (LPAT), which is being developed by NATS with Funke Avionics.

LPAT is being positioned as a portable, battery powered and affordable device that will provide the minimum functionality needed to make a GA pilot visible to other airspace users, as well as to provide warnings against other suitably equipped aircraft.

Jonathan added: “For those that either can’t afford to invest in a transponder, or don’t have the power to run one or are weight restricted – like some very light aircraft, gliders or perhaps a hot air balloon – LPAT could be the answer.”

LPAT can send and receive ADS-B signals allowing pilots to have greater awareness of the traffic around them; however it does not match a full transponder in terms of functionality. For example, it is not currently compatible with TCAS and it use will not allow access to some airspace if a transponder is mandatory.

Jonathan concludes: “Transponders are the ideal solution for some GA aircraft, but any additional information pilots and NATS can have about aircraft in the sky, the better and safer for everyone.”

More details on the trial and how to take part are available on the NATS blog: nats.aero/blog/2015/01/helping-general-aviation-stand-crowd