- Understanding aviation noise
- Noise annoyance management
Noise exposure ≠ Noise impact
In order to reduce the impact of noise on communities the majority of efforts guided by ICAO initiatives have focused on reducing noise exposure (as measured by some form of Leq). As we shall see elsewhere, experience has shown that efforts to reduce noise exposure have not always delivered the expected improvements to impact, which has encouraged the refinement of approaches to impact management as explained in the section on “Improving Impact Management”.In order to reduce the impact of noise on communities the majority of efforts guided by ICAO initiatives have focused on reducing noise exposure (as measured by some form of Leq). As we shall see elsewhere, experience has shown that efforts to reduce noise exposure have not always delivered the expected improvements to impact, which has encouraged the refinement of approaches to impact management as explained in the section on “Improving Impact Management”.
ICAO Balanced Approach and guidance
Regulatory responses to aircraft noise are influenced at the global level by the UN International Civil Aviation Organisation (ICAO), and specifically its ‘Balanced Approach’ to noise management, adopted at the ICAO 33rd Assembly on Aircraft noise in 2001. The rationale for the Balanced Approach was built on the concept that airports face their own specific circumstances in terms of levels of traffic, the amount of night flying, proximity of the airport to built-up areas, design of flightpaths, and attitudes of local residents to noise. By providing a simple framework focusing on the core aspects of noise management, airports would therefore be able to have the flexibility to adopt their own approaches as appropriate to their own situation. This also recognises that Member States may already have their own noise regulations and policies in place.
The Balanced Approach provides a flexible way to identify and transparently address specific noise problems. It comprises four principal elements:
- Reduction of noise at source – by encouraging the use of quieter aircraft;
- Land-use planning and management – to prevent noise sensitive developments close to airports and flight paths, and to mitigate noise impacts (i.e. through sound insulation);
- Noise abatement via alternative operational procedures that separate aircraft from noise sensitive areas or reduce thrust settings and therefore the noise generated by aircraft; and,
- Operating restrictions on aircraft at sensitive times (e.g. at night) or in terms of absolute numbers of movements
As well as these guiding principles, a supporting guidance document ‘Guidance on the Balanced Approach to Aircraft Noise Management’has been produced to support airports in implementing interventions within these core elements. Key to note is that this document states that operating restrictions should only be applied as a last resort, after the other elements have been considered and applied where appropriate. This acknowledges the central role played by aviation in the global socio-economic system, and that reductions in noise can be achieved at a lower economic cost when a stronger focus is placed on the other Balanced Approach elements.
The ICAO Balanced Approach is transposed into European Law through EU Directive 2002/30/EC, later replaced by Regulation (EU) No 598/2014. In the EU, legislation is set centrally, although its implementation into local law, occurs at the Member State level. This ensures that the exact implementation of the four Balanced Approach elements is at the behest of the contracting states, who can also choose to delegate their powers to a competent authority. Below this level, airports are generally empowered to implement their own specific interventions designed to reduce noise exposure and thereby impact, although this is commonly supported by external stakeholders, particularly national airspace providers. Doing so is intended to ensure that aircraft noise problems at individual airports can be managed in both an environmentally and economically responsible way - achieving maximum environmental benefit in a cost-effective manner.
Noise Policies in Airport Regions
In 2015, the review by Airport Regions Council “Noise Policies in Airport Regions” found that the “must have” mitigation procedures strongly implemented in almost every airport studied were:
- Noise monitoring;
- Flight operations, such as continuous descent operations;
- Passive protection, such as noise insulation;
- Ground noise related measures, such as auxiliary power units;
- Noise related fines – for noisy aircraft that exceed stated limits.
The report also found that developing trust amongst noise stakeholders was an essential characteristic of good noise management, with dissemination of noise data, and engagement through tools such as dialogue forums being important.