Aircraft noise

About: Aircraft noise is a research topic. Over the lifetime, 3051 publications have been published within this topic receiving 32039 citations.

Air traffic assignment to reduce population noise exposure using activity-based approach

Abstract: Aircraft noise has been regarded as one of the major environmental issues related to air transport. Many airports have introduced a variety of measures to reduce its impact. Several air traffic assignment strategies have been proposed in order to allocate noise more wisely. Even though each decision regarding the assignment of aircraft to routes should consider population exposure to noise, none of the air traffic assignment strategies has addressed daily migrations of population and number of people exposed to noise. The aim of this research is to develop a mathematical model and a heuristic algorithm that could assign aircraft to departure and arrival routes so that number of people exposed to noise is as low as possible, taking into account temporal and spatial variations in population in an airport’s vicinity. The approach was demonstrated on Belgrade airport to show the benefits of the proposed model. Numerical example showed that population exposure to noise could be reduced significantly by applying the proposed air traffic assignment model. As a consequence of the proposed air traffic assignment, overall fuel consumption increased by less than 1%.

Auralisation of airplanes considering sound propagation in a turbulent atmosphere

Abstract: Aircraft noise is a major issue in urban areas. Due to a rising level of urbanisation and the continuing growth of air traffic more people are exposed to aircraft noise than ever. Methods currently used for assessing the impact of aircraft noise on humans consider mostly energetic quantities, and not the dynamic character of the sound. Therefore, in order to obtain a more accurate picture of the impact of aircraft sound it may be helpful to assess how the audible sound is perceived. Auralisation is a method for rendering audible sound fields and may be used to create audible aircraft sound. A tool was developed to auralise the sound of jet airplanes and consists of an outdoor sound propagation model and an emission synthesiser. The emission synthesiser computes an emission signal consisting of tonal components and broadband noise. The spectral components vary over time and take into account directivity. An inverse propagation model was developed to compute back from a receiver to source in time-domain. An automated procedure was developed to extract features from the resulting signal. These features were then used to directly synthesise the emission as function of time, and this signal was propagated to the original receiver resulting in an auralisation that should reproduce the recording it is based on. To validate the auralisation tool, a listening test was conducted where participants were presented with recordings and auralisations and had to rate their similarity. Results indicate that differences exist between the auralisations and recordings. Improving the synthesis of the blade passing frequency is expected to improve the similarity between auralisations and recordings. Finally, fluctuations can typically be noticed when listening to sound from a distant aircraft, and one cause of these fluctuations is atmospheric turbulence. A computationally fast algorithm was developed to take into account the amplitude and phase modulations that arise as the sound propagates through the turbulent atmosphere. According to the author the method results in improved plausibility of the auralisations.

Aircraft Noise Effects on Sleep—Results of a Pilot Study Near Philadelphia International Airport

Abstract: Current objective data on aircraft noise effects on sleep are needed in the US to inform policy. In this pilot field study, heart rate and body movements were continuously measured during sleep of residents living in the vicinity of Philadelphia International Airport (PHL) and in a control region without aircraft noise with sociodemographic characteristics similar to the exposed region (N = 40 subjects each). The primary objective was to establish the feasibility of unattended field measurements. A secondary objective was to compare objective and subjective measures of sleep and health between control and aircraft noise exposed groups. For all measurements, there was less than 10% of data loss, demonstrating the feasibility of unattended home measurements. Based on 2375 recorded aircraft noise events, we found a significant (unadjusted p = 0.0136) exposure-response function between the maximum sound pressure level of aircraft noise events and awakening probability inferred from heart rate increases and body movements, which was similar to previous studies. Those living near the airport reported poorer sleep quality and poorer health than the control group in general, but when asked in the morning about their last night’s sleep, no significant difference was found between groups. Neither systolic nor diastolic morning blood pressures differed between study regions. While this study demonstrates the feasibility of unattended field study measurements, for a national study around multiple US airports refinements of the study design are necessary to further lower methodological expense and increase participation rates.

Noise prediction toolbox used by the DLR aircraft noise working group

Abstract: Focus of the activities of the aircraft noise working group of the German Aerospace Center (DLR) is the development and application of aircraft noise calculation models. The different tools currently in use are covering the range from best practice models like FAA´s INM or the German AzB up to the sophisticated partial-sound-source models SIMUL and PANAM, which were developed at DLR during the last years. Consequently, the field of application is very large – reaching from the classical aircraft noise prediction tasks for land-use planning up to a noise optimization already during conceptual vehicle design. This paper gives an overview on these tools, typical applications as well as their advantages and limitations. Special attention will be paid on the SIMUL and PANAM models, which are currently used mainly for scientific applications.