The aviation industry has a vital role in supporting Australia’s successful economy. In Australia, aviation activity is expected to increase by more than 60 per cent over the next 20 years. This growth must be accompanied by actions to manage even further the impact of the aviation sector on noise.
All parts of the industry are already working on noise reduction measures.
Quieter aircraft technology
Reducing noise is a priority for all global aircraft manufacturers. This is achieved by improving aerodynamic design, using turbofan engines and lining engines to dampen noise.
A growing number of modern aircraft are now fitted with navigation systems that use satellite-assisted guidance. These systems allow aircraft to use GPS information to fly with a high degree of accuracy with only a small variation in the actual routes flown from one aircraft to another. This technology is known as Smart Tracking.
In certain circumstances, Smart Tracking flight paths can be designed to curve around obstacles (high terrain or buildings), follow existing noise corridors (highways) or to avoid noise sensitive areas in favour of overflying industrial land or other non-residential areas. This technology has already been successfully implemented at some of the busiest and most geographically challenging airports in the world.
The aviation industry is seeking opportunities to minimise aircraft noise, by trialling new procedures such as flight paths that avoid residences as far as possible. Often these trials are undertaken as a result of issues raised by communities.
Continuous descent approach
A Continuous Descent Approach (CDA) is a method by which aircraft approach airports prior to landing. It is designed to reduce fuel consumption and noise impacts compared to conventional approaches and involve maintaining a constant three degree descent angle during landing, until meeting the airports Instrument Landing System (ILS). Instead of approaching an airport in a step fashion, as is the conventional method, CDA allows for a smooth, constant-angle descent to landing.
Reduced thrust take-off
To ensure a safe take-off, airlines consider several factors when calculating required engine thrust levels. A reduced thrust takeoff is a takeoff that is accomplished utilising less thrust than the engines of an aircraft are capable of producing. The primary advantage to a reduced thrust takeoff is cost savings through increased engine life and reduced overhaul costs. Secondary advantages include potential to reduce aircraft noise and fuel savings.
During landing, a combination of reverse thrust and wheel brakes slow aircraft down on the runway. Reverse thrust uses engine panels to direct air forwards so the engine can help in slowing down the aircraft. Runway length and condition determine how much reverse thrust pilots apply.