One of the most significant negative impacts of airports on their surroundings is aircraft noise. Minimising airport noise pollution, however, is easier said than done. On one hand, the economy is growing, causing an increase in demand for flights and the development of the region. On the other hand, airports are becoming capacity constrained and pressured because of environmental limitations put into effect by (local) authorities. The question therefor is, how can we achieve maximum environmental benefit on reducing the increase of aircraft noise, whilst ensuring economic growth?
The reason why
Due to local and national pressure, airports are facing problems with the increasing noise load of aircraft operations. Airports are constrained in capacity, due to operational limitations and increasing opposition to airport expansions. The result: uncoordinated policy developments which lead to the disruption of the airport’s role in the economic development. Hence it is of great importance to find the balance between the environment and economy – especially taking into account the growing concern on health issues, all while expecting air traffic to double within 20 years.
At Adecs Airinfra Consultants, we have been aiming to tackle these problems through what is called ‘the balanced approach’. This approach, adopted by ICAO, aims to reduce noise pollution around airports using flexible and transparent processes. The European Commission has also implemented this approach because of the increasing impact airports have, both economically and environmentally. One of the innovation programmes initiated by the Commission, is the ANIMA project. This project focusses on improving the lives of people at and around airports while supporting stakeholders. Their research expresses the need for this balanced approach.
The way how
Every airport is on a unique location, dealing with unique circumstances. To achieve maximum environmental benefit and ensure economic growth, the balanced approach focusses on an airport-by-airport approach, taking into account the specifics of the airport. First of all, every airport needs to identify its noise problems and define an objective to reduce annoyance to a certain level. A useful procedure for this is to determine the noise contours for a scenario, based on aircraft type, the number of movements, the time of day and the type of flight procedure. Next, it is time for finding that balanced result. To do so, there are four elements that need to be focussed on:
Reduction of noise at the source
The first element is mainly focussing on the development of new technologies by the aircraft- and engine manufactures, but also on the fleet evolution of airlines. Future noise scenarios should consider the noise performance trend of the fleet. Unfortunately, the reduction of noise at the source is not within the control of individual airports, but can be encouraged through research studies or by improving the communication among stakeholders. This would improve transparency, mutual understanding and therefore improves decision-making.
Land use planning and -management
The second element’s objective is to minimise the number of people affected by aircraft noise by managing the use of land around an airport. Land use measures should be identified at an early stage to maximise benefits over the long term. New airports must take appropriate measures so that land use planning is taken into account, including locating away from sensitive areas and discussing development around the airport with local authorities. Existing airports, however, are limited but can still act transparent to communities, by providing environmental information and defining and updating zones around the airport associated with different noise levels.
Again, individual airports are not in the control of the area development. Yet, by working closely with the responsible authorities, it is possible to manage the development. Sharing the noise impact of airport operations will help and support appropriate land use planning and control measures. In the Netherlands for example, noise zoning enables designating the use of (shares of) land, depending on the noise exposure. For Amsterdam Schiphol, the latter comprises ‘no noise-sensitive buildings’ within the 70 Lden dB(A) contour and ‘no new noise-sensitive buildings’ within the 58 Lden dB(A) contour. Additional to these planning instruments, airports can fall back on mitigating instruments such as land acquisition and noise barriers, or financial instruments like promoting noise insulation.
Noise abatement operational procedures
The third element focusses on route optimisation in correlation to minimising noise. A few measures to achieve this, are the use of noise preferential flight paths (to avoid noise-sensitive areas) and implementing newly designed take-off and/or approach procedures to optimise – or rather minimise – noise exposure. Nevertheless, these measures may only be implemented when a noise problem has been demonstrated or is anticipated and safety of operations has been guaranteed. Additionally, implementing these procedures might significantly affect the air traffic capacity. Successful implementation depends heavily on close collaboration between airports, authorities, air navigation service providers, operators, manufacturers and research organisations.
Operating restrictions
The fourth element may only be put in action after close consideration of the previous three elements. This element is defined as a ‘noise related action, limiting or reducing an aircraft’s access to an airport’. ICAO urges authorities not to introduce operating restrictions on aircraft that are compliant before phasing-out the aircraft which actually exceed the prescribed noise levels.
Restrictions can vary from aircraft specific restrictions to partial restrictions applying for only a certain period of time during the day (e.g. curfew). The introduction of these restrictions can be complex. Before put into action, the airport must among others, research the effect on the air traffic network, give operators notice duly in advance (if no suitable alternatives appear) and take into account the economic impact.
Our perspective
We have been working with the balanced approach for some time now and have adopted this in our procedures. Currently, the balanced approach focusses only on airports operating more than 50,000 flights annually, while it would be as interesting to the smaller, regional airports as well. They are facing the same environmental challenges and this approach could help them move in the right direction.
If you would like to know more about how we can help you with a balanced approach or if you would like any further information, please contact us.