Major changes to flight paths are underway across Australia's three largest cities.
Authors
- Milad Haghani
Associate Professor and Principal Fellow in Urban Risk and Resilience, The University of Melbourne
- Abbas Rajabifard
Professor in Geomatics and SDI, The University of Melbourne
- Gavin Lambert
Director, Iverson Health Innovation Research Institute, Swinburne University of Technology, Swinburne University of Technology
- Rico Merkert
Professor in Transport and Supply Chain Management and Deputy Director, Institute of Transport and Logistics Studies (ITLS), University of Sydney Business School, University of Sydney
- Taha Hossein Rashidi
Professor of Transport Engineering, UNSW Sydney
Brisbane's new runway has already shifted aircraft noise onto suburbs that never experienced it before .
Western Sydney Airport's finalised routes will bring flight paths to entirely new parts of the city from 2026. Sydney's Mascot Airport has also released a draft plan for 2045 , signalling further changes to flight patterns and noise exposure as flight numbers grow. It forecasts a 75% increase in annual passengers.
Melbourne's proposed third runway would alter noise patterns across the city's west for decades.
In each case, thousands of residents who did not buy or rent under a flight path may soon be exposed to regular aircraft noise. For many, the expected noise levels are significant.
Decades of international research show well-documented and consistent links between long-term exposure to aircraft noise and harms to health and wellbeing - as well as hits to property values.
This raises questions for any community affected by new or redesigned flight paths. What exactly are these wellbeing and financial impacts, and how should they be recognised or offset? How do other countries address them?
What long-term aircraft noise does
Research from many countries shows long-term aircraft noise has clear and measurable effects on health , including sleep , children's learning , wellbeing and mental health , and property values .
These effects appear consistently across different regions, airport settings and study methods .
Health and sleep
Long-term exposure to aircraft noise is linked with higher risks of high blood pressure , heart disease and stroke .
These effects tend to be strongest where night-time noise is high . The mechanism may entail noise activating the body's stress response , placing strain on the cardiovascular system over time .
Even moderate levels of night-time aircraft noise can increase insomnia across all age groups, but particularly in children .
Children's learning
One of the clearest findings in the entire aircraft-noise literature is its impact on children's learning .
When schools are located under busy flight paths, students make slower progress in reading, in particular. These effects add up to months of learning lost each year . These impacts accumulate over time, rather than children adapting to the noise.
A small rise in noise - even just a few decibels - is also associated with measurable increases in child hyperactivity .
Property values
Airports increase economic activity and can even raise property values regionally, through better connectivity, jobs and investment.
But these broader regional benefits do not erase the local, often uneven costs borne by households directly under flight paths. This is particularly the case for those far enough from the new airport to miss out on the economic uplift, yet close enough to experience frequent low-altitude flights. For these homes, the net effect on price is often negative.
Recent analysis of thousands of individual house sales in Melbourne found that homes further from the airport runway - but otherwise similar in standing - sell for up to 37% more than those closer in.
International evidence shows the same pattern. Across multiple studies, house prices fall by about 0.5-0.6% for every 1 decibel of aircraft noise.
Countermeasures are limited
Airports generate jobs, investment and economic activity - but the costs are partly carried by the households that live under the flight paths. The core policy problem is whether those costs are recognised and offset.
Unlike other countries, Australia has done little to address those impacts on households.
Curfews at a few airports reduce night-time operations, but they do nothing for daytime noise. Many major airports - including Melbourne, Brisbane, Perth and the new Western Sydney Airport - have no curfew at all.
Sydney Airport's insulation and acquisition program in the 1990s insulated more than 4,000 homes and acquired over 160 properties at a cost of about A$300 million - the last time Australia implemented noise mitigation on a large scale.
A planned insulation program for Western Sydney Airport will help. However, an earlier investigation found that although the modelling predicted thousands of homes would be affected, only a small fraction would be eligible for insulation.
For other major airports - such as Perth, Adelaide and Melbourne - insulation requirements apply only to new residential developments. So, long-standing residents recently exposed to new or intensified flight paths receive no support.
Other countries do it better
Many countries treat noise mitigation as a core part of airport expansion, with schemes that support existing communities affected by changing flight paths.
In the United States, airports receive federal funding to insulate homes, schools and community buildings under established flight paths.
Airports such as Chicago O'Hare have insulated thousands of homes through these programs. When flight paths or operations change, airports update federally approved noise maps, which can expand eligibility.
In Maryland, some counties offer a 50% reduction in property tax for owner-occupied homes in designated aircraft-noise zones around major airports.
In the United Kingdom, Heathrow has offered noise-insulation funding to about 20,000 homes within defined noise-exposure bands.
What can be done to support residents?
Australia's current mitigation measures, at least in relation to some airports, fall short of offsetting the full impact on affected residents.
When airport expansions generate substantial economic benefits, a portion of that value could be used to directly support the communities that absorb the noise burden.
The most immediate and practical steps could be:
offering much broader insulation support for homes, schools and childcare centres that are newly exposed to high aircraft noise, rather than narrow and time-limited schemes
introducing land-tax or council rates relief for households inside defined noise-exposure zones.
A fairer mitigation approach would ensure the benefits of aviation expansion are not built on uncompensated losses for the people living under the flight paths.
Gavin Lambert receives funding from the National Health and Medical Research Council of Australia, the Australian Economic Accelerator, and CSIRO-Data 61. He is affiliated with Hypertension Australia, acting in the role of Company Secretary. He has previously received research funding from the CASS Foundation, Diabetes Australia Research Trust, Heart Kids, the Victorian Managed Insurance Authority and Medibank Private Limited. He has received consulting fees and travel and research support from Medtronic.
Rico Merkert receives funding from the ARC and various industry partners. He frequently works with airlines, including Qantas and Virgin Australia.
Abbas Rajabifard, Milad Haghani, and Taha Hossein Rashidi do not work for, consult, own shares in or receive funding from any company or organisation that would benefit from this article, and have disclosed no relevant affiliations beyond their academic appointment.
