A new satellite-supported system designed to replace radar as New Zealand's main aircraft tracking technology will be rolled out across the country.

Airways New Zealand has a deal with a supplier of ground infrastructure for its Automatic Dependent Surveillance - Broadcast (ADS-B) network.

The $12 million network will provide a more detailed picture of airspace than is currently possible with radar.

The ADS-B network updates the aircraft's location every second, while existing radar calculates the position approximately every five seconds.


''It will enhance the way aircraft are monitored in domestic airspace and will play a crucial role in supporting the growth of air travel in New Zealand," Airways chief operating officer Pauline Lamb said.

ADS-B uses satellite GPS systems, aircraft transmitters and a network of ground station receivers to follow aircraft with a more precise level of accuracy.

With a network of 28 ground receivers installed even in remote locations, the system will detect aircraft in places where there is limited radar coverage, like behind mountain ranges and at low altitudes in regions such as the Hawkes Bay, Gisborne and much of the South Island's west coast.

She said no air traffic control jobs would be lost but the way controllers worked would change with greater access to surveillance. Aircraft operated by airlines in New Zealand were already equipped to enable them to use the new system but some smaller operators may have to retrofit their planes when the system in mandatory for all from 2021.

While the basic idea of radar had its origins more than a century ago, it was further secretly developed by the Allies before and during World War II. The term RADAR was coined in 1940 by the United States Navy as an acronym for RAdio Detection And Ranging.

ADS-B is the global standard for airspace surveillance and its introduction here is a key part of the New Southern Sky programme, the Government's 10-year plan to modernise this country's aviation system.

Airways said an intense period of air traffic growth is forecast for the Asia Pacific region. Visitor numbers to New Zealand are set to hit 4.5 million annually by 2022 (up from 3.3m now) and with 99 per cent of them arriving by air, ADS-B will help to provide the airspace capacity to handle increased numbers, Lamb said.

"The precise tracking ability and increased surveillance coverage ADS-B provides allows us to reduce the separation between aircraft to have them safely fly closer together and on the most direct route, improving the flow of traffic and reducing environmental impacts," Lamb said.

In an emergency or search and rescue situation, this level of detail would mean we would be able to provide help to an aircraft in distress more quickly.


"In an emergency or search and rescue situation, this level of detail would mean we would be able to provide help to an aircraft in distress much more quickly."

Airways has awarded a contract to French multinational Thales to provide ground equipment for the $12m network.

Installation will begin in early next year and the first phase of the network will be operational by the end of December 2018 when a Civil Aviation rule is planned to be implemented requiring all aircraft flying in controlled airspace above 24,500 feet in New Zealand to be using ADS-B.

The requirement will be extended to all controlled airspace by the end of 2021 when the current radar system will be de-commissioned. At the moment New Zealand is covered by one constellation of high orbit satellites but by then this would be duplicated.

A smaller radar network will remain in place in New Zealand as a back-up.

ADS-B extends the capability of Multilateration radar systems currently in place at Queenstown Airport and Auckland Airport.

Airways looks after key aviation infrastructure around New Zealand and manage the more than 1 million traffic movements per year into and around New Zealand's 30 million square kilometres of airspace.