Australian air traffic service provider Airservices Australia completed the installation and commissioning of its nationwide automatic dependent surveillance - broadcast network in late December, with the country becoming the first in the world to provide nationwide ADS-B coverage.

ADS-B is available to suitably equipped aircraft above flight level 300 through ground stations at 28 sites throughout the country, providing radar-like coverage over continental Australia for the first time. An aircraft's call-sign, position, altitude, velocity and other data are broadcast twice every second. The accuracy of the information displayed on air traffic controllers' screens allows separation standards to be reduced from 30nm (55.5km) to 5nm.

Airservices Australia embarked on its ADS-B project in early 2004, signing a contract with Thales for the supply of 57 ADS-B ground stations to be installed at 28 sites. The programme was the largest deployment of ADS-B ever planned and followed a trial of the technology in the Burnett Basin region, north of Brisbane in Queensland.

The project was originally due to be completed by the end of 2005 but proved more complicated than expected, with delays attributed to the provision of duplicated communication links that are required to enable ADS-B to provide a 5nm separation service.

More than 1,100 aircraft, ranging from single-engined trainers to international airliners, are equipped and approved to operate with ADS-B in Australian airspace, according to Airservices.

"ADS-B is a huge advance in our surveillance capability and provides significant safety benefits," says ADS-B project manager Donna Willis. "Not only does it provide surveillance over remote areas of outback Australia that previously had no coverage at all, but we are also getting early warning of international flights coming over our northern airspace boundary. This helps enormously in setting up an orderly flow into major capital city hubs," Willis adds.

Through reduced aircraft separation standards, ADS-B is expected to minimise delays, improve efficiency and as a result reduce aircraft fuel burn and CO2 emissions.

Meanwhile, Airservices and Thales have completed the latest upgrade, comprising 51 enhancements, to Australia's ATM system, the Australian Advanced Air Traffic System. The enhancements support the introduction of new radar surveillance tracking, barometric pressure (QNH) sensor processing and radar bypass services.

Source: Flight International