Noise abatement around Frankfurt Airport
Frankfurt Airport (Fraport) is Germany’s largest, Europe’s third largest and the world’s ninth largest airport. Up to 1,500 planes take off and land here every day. The noise pollution for local residents, particularly those living right under the flight path, is extremely high. As the latest noise impact research shows, aircraft noise has highly detrimental effects on health. Effective measures to protect the communities concerned are therefore essential.
A distinction is made between active and passive noise abatement. Active aircraft noise abatement mainly consists of technologies to avoid and reduce the noise at source and therefore focuses on the aircraft itself. It may also include optimising flight paths or varying route or runway schedules in order to redistribute noise emissions from air traffic. Modern flight operation procedures allow aircraft to fly at higher altitudes for longer, thus reducing noise at ground level. And not least, it is important to create an enabling environment for more effective implementation of noise abatement schemes.
In contrast, passive noise abatement protects people by means of structural modifications. Areas defined as severely affected are entitled to certain passive aircraft noise abatement measures: for example, homeowners may claim reimbursement of the costs of installing soundproofing. In addition, the construction of facilities which need particular protection from noise, such as hospitals, elderly care homes and convalescent homes, is generally prohibited in these areas.
Legal standards: German Act for Protection against Aircraft Noise
In 2007, the German government amended the German Act for Protection against Aircraft Noise (Gesetz zum Schutz gegen Fluglärm – FluLärmG). The purpose of the Act is to protect the public from hazards, significant disadvantage and nuisance caused by aircraft noise. However, the legislation does not address the issue of active noise abatement but focuses on passive measures, i.e. structural modifications to buildings. The Act must be reviewed regularly, at least every 10 years, to determine whether its objective – to protect the public more effectively from aircraft noise – is being achieved. The German government is required to report on progress to the German Bundestag.
The Act provides for the establishment of noise protection areas (with different protection zones for daytime and night-time) around airfields, based on noise limit values. Depending on the location of their property within the protection area, homeowners are entitled to reimbursement of expenses incurred for structural modifications, i.e. soundproofing, or to compensation for impairment of their outside living area. Prohibitions on the construction of homes and facilities which need particular protection from noise, such as hospitals and elderly care homes, apply in adjacent municipalities.
How effectively does the law protect against noise? Expert reports see a need for action
Two expert reports produced by the Oeko-Institut on behalf of the German Environment Agency (UBA) as part of the review of the German Act for Protection against Aircraft Noise clearly reveal that there is a need for action to give local residents genuine and effective protection from aircraft noise. One of the main criticisms is that the existing legislation does not aim to reduce aircraft noise at source.
The reports therefore call for active aircraft noise abatement measures to be given priority. An analysis of the latest aviation technology reveals considerable untapped potential here. Recent studies in the field of noise effects research also show that both the disturbance caused by aircraft noise and the long-term physiological impacts are more severe than previously assumed. The current noise limits are therefore too low.
Furthermore, the Act differentiates between new and existing airfields or airfields which have undergone substantial structural expansion, and between civilian and military airfields. From a scientific perspective, this unequal treatment of local residents cannot be justified.
Expert report: Weiterentwicklung der rechtlichen Regelungen zum Schutz vor Fluglärm (Further development of legislation on aircraft noise abatement) by the Oeko-Institut on behalf of the German Environment Agency
Active noise abatement: aircraft-based technology, avoidance of populated areas, flight routes
A wide range of measures can be taken to actively reduce aircraft noise. Wherever possible, noise abatement should start with the aircraft itself, which should be equipped with noise reduction technologies, such as vortex generators, which suppress the particularly unpleasant whistling noise produced on the underside of the wings. Lufthansa and Condor have installed this technology on all the aircraft in their A320 fleets, and other airlines are keen to follow suit. The airlines are also progressively replacing the noisy aircraft in their fleets with quieter models. In 2016, Lufthansa completed its phase-out of all its Boeing 737s, which were notorious for producing a large noise footprint.
In addition, people affected by aircraft noise will benefit if the distance between their homes and the noise source is increased. For example, a steeper approach to landing at a 3.2° angle instead of the usual 3° reduces the noise level by increasing the altitude at which an aircraft passes over residential areas.
Rerouting flight paths for takeoff and landing away from densely populated areas does not, in itself, lessen noise emissions but it does reduce the number of people affected by them. Since 2018, a transparent consultation process has therefore been addressing the concerns of all the affected communities. In addition, various technologies have been developed to improve track keeping; fixed turn radiuses help aircraft to stay on course, reducing the size of the overflown area.
The institutional frameworks for active noise abatement also have an important role to play. At the Frankfurt site, continuous monitoring keeps aircraft noise reduction science up-to-date as a basis for implementing potential solutions. In addition, efforts are under way to introduce simplified approval procedures to speed up the process of trialling new noise abatement schemes.
Expert Group on Active Noise Abatement (ExpASS)
Researchers from the Oeko-Institut have provided coordination and support to the Expert Group on Active Noise Abatement (ExpASS) – part of the Airport and Regional Forum (Forum Flughafen & Region, FFR) – since its establishment. Its task is to continuously develop new methods of protecting the public from aircraft noise.
ExpASS brings together representatives of various stakeholder groups – policy-makers, the aviation industry, affected communities, researchers and independent experts – to identify, research and evaluate active noise abatement measures, the aim being to achieve consensus. Its work is facilitated by researchers from the Oeko-Institut, who thus make an important contribution to active noise abatement.
A key milestone in ExpASS’s work is the active noise abatement package published in 2018. It defines measures which can be implemented in the short or medium term as well as long-term schemes and research projects. Other actions focus on the legal aspects and policy frameworks of relevance to flight operations.
A new element is the local consultation process with affected communities on noise rerouting. In many cases, this is about weighing up interests: rerouting a flight path can lessen the impact on large numbers of people in a densely populated conurbation but may make noise pollution worse for a smaller community elsewhere. Maximum transparency is required here. During the second half of 2018, for example, a consultation was held on the possible rerouting of the AMTIX short takeoff flight path in Darmstadt.
The background paper Fluglärm: Rechtliche Expertise, Wissenschaftliche Begleitung, Wirkungsforschung (Aircraft noise: legal expertise, scientific research, impact monitoring) (2016) describes all the various aspects of the Oeko-Institut researchers’ work on noise abatement.