The level of noise you hear from a plane during take-off, landing and during flight can vary. Aircraft noise is influenced by a number of different factors, including:
- The weather, including season, wind & cloud cover
- The height of an aircraft
- Changes in engine thrust
- Type of aircraft
Noise is also subjective person to person and what you hear can be influenced by many different factors including your surroundings and other activities happening in the background.
Sound is measured in decibels (dB). The sound level of typical daytime activities can vary between 40 dB and 85 dB. Typical aircraft noise levels are between 65 dB and 95 dB. Very close to a runway, an aircraft could be as loud as 130 dB.
Weather impacts such as wind, clouds and rain all impact where planes fly and the level of noise experienced.
Wind
At Brisbane Airport seasonal weather patterns affect how often aircraft can fly over the bay. Generally speaking, during the warmer months there are increased northerly and easterly winds at Brisbane Airport, which means flights are more likely to arrive over the city and take-off over the bay. While during cooler months, there are increased southerly and westerly winds, so planes will often arrive over the bay and take-off over the city.
When the wind falls below 10 km/hr at night, Airservices Australia will operate simultaneous opposite direction operations where flights both land and take off over the bay.
When there are high winds in the airfield above 10km/hr, or rain or low cloud, aircraft will be able to land over the bay, however departures would occur over the city. This is needed to make sure that operations are consistent with international rules and standards.
When there are north easterly winds above 10km/hr aircraft would be able to depart over the bay however would need to land over the city. This is also needed to make sure that operations are consistent with international rules and standards.
Cloud
It is common for people often say that aircraft are noisier when it is cloudy. Cloud cover acts like a blanket and can “trap” noise, amplifying it downward.
Rain
Whether it is raining or not also influences how an aircraft can land or take-off. Reduced visibility from rain may require pilots to use specific flight paths to safely land and depart.
A buffer zone is measured by drawing a straight line from the centreline at the end of the runway to the nearest residences.
Brisbane Airport has the largest noise buffer zone of any capital city airport in Australia. Drawing a straight line from the end of the legacy runway, the nearest residence is 6.7km away. Using the same straight line approach, the distance from the end of the new runway to the nearest residence is 6km.
Other Australian airports with a curfew have a much smaller buffer zone, in some cases measuring just 600m from the nearest residences.
Airservices Australia monitor aircraft noise via a number of fixed noise monitors strategically placed around communities close to the airport. Details of the information collected is displayed in the Airservices WebTrak tool which can be found here.
New noise monitors will be placed in the community prior to the opening of the new runway.
In early 2020, BAC developed the first combined Airport/Airservices Aircraft Performance and Noise Program in Australia. Recognising the sensitivity of residents to major changes in aircraft noise patterns, this program includes the provision of six extra noise monitoring terminals in addition to the eight permanent noise monitors already in use by Airservices.
Four temporary noise monitors have been placed in New Farm, Bardon, Carina and Hamilton, plus two permanent noise monitors south of the two runways. The system will allow BAC to monitor how aircraft are performing against the noise abatement procedures, explore noise improvements, and report this information to the community. The additional noise monitors will be shown on Airservices’ WebTrak.
You can find out more about this program here.
For current information on flight paths and aircraft movements at your location, visit Airservices Australia’s Aircraft in your Neighbourhood website.