Aircraft noise is managed by airport use planning, international noise regulations, development of engine technology and land use planning.
Aircraft noise controlling is comprehensive long-term work that aims for specifying operating practices for reducing noise pollution. The most important goal is to have as few people as possible to live within the area of aircraft noise. Finavia works in close cooperation with municipalities located in the vicinity of airports and routes to allow municipalities to take noise areas and their vicinity into account when planning new residential areas.
Methods for controlling aircraft noise include runway use principles and flight route planning. These actions direct traffic to the least populated areas within the limits of flight safety regulations. At Helsinki Airport, for example, noise pollution is reduced by choosing aircraft takeoff and landing directions. Flight route planning can reduce noise substantially during takeoffs.
The noise management plan of Helsinki Airport describes all the essential methods for reducing and controlling the noise caused by Helsinki Airport.
Safety issues present special challenges to noise control during landings because the final approach is made in line with the runway and the altitude and distance to the runway are controlled with the landing equipment. Maintaining the safety distance between aircraft landing on the same runway is important especially during peak hours.
Aircraft equipment is subject to international noise regulations and due to general technological development new aircraft produce significantly less noise than the older ones.
European Union’s Environmental Noise Directive (2002/49/EY) has been implemented in Finland with a change 459/2004 to the Environmental Protection Act. The directive requires that the member states make noise investigations in 2012 for densely populated areas and busy highways, railways and airports and noise prevention plans in 2013.
During the second stage in 2012, noise investigation was made for all areas with a population of over 100,000 people, busy highways (2,080 km) and railways (375 km) and Helsinki Airport. Noise investigation of Helsinki-Malmi Airport is included in the noise investigation of the City of Helsinki and the noise investigation of Helsinki Airport is made separately. The noise investigations describe the situation in 2011. The results of the noise investigations have been reported to the Ministry of Environment and the European commission.
In noise investigations conducted in accordance with the Environmental Noise Directive, noise areas are described using the Lden unit (noise level / 24h) where noise in different times of the day are given different emphasis: 5 dB is added for noise occurring at 7–10 p.m. and 10 db is added for noise occurring at 10 p.m.–7 a.m. Noise levels described using Lden values increase quite strongly if there are a lot of noise events in the evening or at night: the calculated value of an aircraft flying in the evening, for example, is equal to over three aircraft flying in the daytime and one night flight is equal to ten daytime flights.