Reports & Statistics

Noise and Flight Path Monitoring System

Under its environmental responsibilities Airservices Australia has established a Noise and Flight Path Monitoring System at Australia 's major airports, including Cairns, Brisbane, Sydney, Canberra, Melbourne, Essendon, Adelaide and Perth.

This NFPMS is the world's largest, most geographically-spread system of its type. The complete system is operated or controlled from Canberra Head Office.

Around each of the airports is a number of noise monitoring terminals (NMTs). The NMT basically consists of a microphone atop a 6m mast and an electronics box. The noise level to which the microphone is exposed over the range of 30 to 130 dB(A) is continuously measured and transmitted via a data line to the NFPMS central computer where it is processed and stored for later analysis. Apart from measuring the aircraft noise, the NMT also continuously monitor the background noise.

The system is also connected to the secondary surveillance radar at each airport to acquire flight track information on aircraft operating into and out of the airport.

When the level and duration of noise generated by any noise source in the vicinity of the NMT location exceed the threshold level and duration that have been set for the detection of aircraft noise, a noise event is recorded. The time at which the noise event is recorded, and the NMT location where the noise event is recorded, is checked against movement times and radar tracks of aircraft operating in the vicinity. If the time and NMT location of the noise event match the movement time and radar track of any aircraft, the noise event is attributed to that aircraft. Otherwise it is regarded as part of the background noise.

The NFPMS is an automated multi-user system. On a map display on each airport, the system displays is the noise levels measured by each of the NMTs and the flight tracks of the aircraft in the vicinity of the airport.

The data stored by the NFPMS can be recalled to display on request the tracks flown by any user selection of aircraft operations, together with the noise levels that those operations produced at the NMTs. The track information includes aircraft altitude and speed. The system includes statistical and acoustical computation software to undertake analysis of noise or flight track information as required by the user.

Regular NFPMS quarterly reports that contain tabular and graphical summaries of noise and aircraft movement data for each airport are produced. These reports include aircraft movement statistics such as runway usage by the various categories of aircraft and movement profiles.

It compiles track density plots consisting of a map of the airport and its surrounds, displaying with colour coding the number of aircraft movements over the area surrounding the airport, over selected time periods.

The system includes the capability to automatically analyse aircraft tracks by defining geometric windows and corridors through which aircraft are expected to pass, and highlighting and listing those tracks that deviate from the defined areas or altitude. The analysis can be selective on either specification of aircraft type or the route being flown.

The NFPMS is a valuable tool to assist in the environmental management of aircraft operations in the vicinity of airports. ln a more general sense, data from the system benefits air traffic control planning and traffic analysis and enhances planning for the use of airspace and runways.

The NFPMS collects noise and flight path data 24 hours a day, seven days a week. It also accumulates flight plan and weather data.

The information collected is used by Airservices Australia to:

• determine the contribution of aircraft to overall noise exposure;
• assess the effects of operational and administrative procedures for noise control and compliance with these procedures;
• assist in planning of airspace usage;
• validate noise forecasts and forecasting techniques;
• assist relevant authorities in land use planning for developments on areas in the vicinity of an airport;
• provide reports to, and responses to questions from, Government, members of parliament, industry organisations, Federal Airports Corporation, community groups and individuals; and
• assist in answering noise complaints about aircraft operations from the general public.