Pilots flying into Schiphol airport at night comment it is easy to find, they just have to follow the dark patches that are leading to the runway. Years of regulations and sensible planning have made sure the planes are not flying over main residential areas in the Netherlands. A very different story compared to airports around the globe. Still the noise pollution discussion is never relenting. People experience aircraft noise as a nuisance and oppose vigorously to changes in routes and procedures that have a negative impact on them. A change that is beneficial for one community is likely to hurt another community. The discussion on how aircraft noise should be distributed (e.g., concentrated or dispersed) requires effective communication with all stakeholders about the aircraft noise exposure.
In communication of aircraft noise, aggregated noise metrics such as Lden, Lnight, LAeq plotted on a charts using contour lines are used extensively. These metrics are useful for spatial planning and decision making. The sound levels during each aircraft noise event are ‘reduced’ to a (weighted) average value. However, these aggregated metrics have strong shortcomings when it comes to informing the general public. It takes considerable explanation before the metrics are understood; the metrics are too technical and individual aircraft noise events are no longer recognisable. This leads to misunderstanding and possibly mistrust of the information presented about aircraft noise. Most importantly a contour on a chart has little meaning to the general public. Additional information is needed to effectively communicate about aircraft noise.
We feel that our aircraft noise visualizations can improve the situation. We create short videos showing the aircraft noise footprint as the aircraft departs or approaches the airport. The visualizations are easy to understand. For example, take a look at the visualisation for a new standard instrument departure (SID) procedure.
Example of Noise Visualization of a New Departure Procedure
[vc_separator type=’transparent’ position=’center’ color=” thickness=’1′ up=” down=”]The blue line represents the new SID. The aim of the new SID is to guide the aircraft accurately in between two residential areas. The noise footprint moves with the aircraft. The colour of the footprint indicates the noise level. The noise levels decrease when the aircraft gains altitude and reduces power. The ‘poles’ in the two residential areas show the instantaneous noise level as the aircraft passes. You can watch the video here. By adding the actual aircraft noise and the typical background noise for these two locations to the video, people can experience the sound via a click on the screen.
Visualisations aren’t only useful for communication about proposed procedure changes. Another great application is incident management. When an incident occurs, and a certain aircraft does cause a storm of complaints, a visualisation of that flight will help in the discussion afterwards.
Recent developments are interactive tools that give an aircraft noise forecast – similar to the weather forecast. These tools provide the annual number of aircraft movements and the likely number of aircraft movements in the next hours together with the noise levels, distance to their location, the aircraft altitude, and sound clips. These tools are not only useful for residents but also for prospective buyers to decide whether to buy a property close to an airport or not.
To communicate effectively about aircraft noise issues, it is important to realize that different stakeholders have different information needs. Information that is tailored to the information needs of each stakeholder will benefit the discussion on how aircraft noise should be distributed. At To70 we have developed a range of models and tools to provide each stakeholder with information tailored to their needs.
About To70. To70 is one of the world’s leading aviation consultancies, founded in the Netherlands with offices in Europe, Australia, Asia, and Latin America. To70 believes that society’s growing demand for transport and mobility can be met in a safe, efficient, environmentally friendly and economically viable manner.