Aircraft noise pollution
[1][2][3] Governments have enacted extensive controls that apply to aircraft designers, manufacturers, and operators, resulting in improved procedures and cuts in pollution.
Aircraft noise is noise pollution produced by an aircraft or its components, whether on the ground while parked such as auxiliary power units, while taxiing, on run-up from propeller and jet exhaust, during takeoff, underneath and lateral to departure and arrival paths, over-flying while en route, or during landing.
The mechanical sources produce narrow band high intensity peaks relating to the rotational speed and movement of the moving parts.
The high velocity jet leaving the back of the engine has an inherent shear layer instability (if not thick enough) and rolls up into ring vortices.
[4] The PowerJet SaM146 in the Sukhoi Superjet 100 features 3D aerodynamic fan blades and a nacelle with a long mixed duct flow nozzle to reduce noise.
Elevated workplace or other noise can cause hearing impairment, hypertension, ischemic heart disease, annoyance, sleep disturbance, and decreased school performance.
[9][10] Elevated noise levels can create stress, increase workplace accident rates, and stimulate aggression and other anti-social behaviors.
[13] A large-scale statistical analysis of the health effects of aircraft noise was undertaken in the late 2000s by Bernhard Greiser for the Umweltbundesamt, Germany's central environmental office.
The results were then corrected for other noise influences in the residential areas, and for socioeconomic factors, to reduce possible skewing of the data.
[14] For example, a day-time average sound pressure level of 60 decibels increased coronary heart disease by 61% in men and 80% in women.
As another indicator, a night-time average sound pressure level of 55 decibels increased the risk of heart attacks by 66% in men and 139% in women.
Statistically significant health effects did however start as early as from an average sound pressure level of 40 decibels.
Cabin noise can be studied to address the occupational exposure and the health and safety of pilots and flight attendants.
[20] Simulated aircraft noise at 65 dB(A) has been shown to negatively affect individuals’ memory and recall of auditory information.
[22] A BAC of 0.10 is double the legal limit required to operate a motor vehicle in many developed countries such as Australia.
In the United States, since aviation noise became a public issue in the late 1960s, governments have enacted legislative controls.
Then, the benefits of building retrofit strategies such as roof upgrading, window glazing improvement, fireplace baffling, caulking construction seams can be evaluated.
[32] Usage of satellite-based navigation systems can contribute to noise relief, trials in 2013–14 found, though results were not always beneficial due to concentrating flight paths.
