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Using Flight Data Recorder Data to Determine Aircraft Noise Levels in the Vicinity of Airports CHAPTER TWO Aircraft Noise 66 INTRODUCTION Airport operators, especially those operating airports located close to residential areas, need to evaluate noise levels of individual aircraft in the vicinity of the airport. (...) In total, more than 2,000 noise level values were recorded for various points on the ground. (...) The highest noise measurement levels are rounded to integers.
Language:English
Score: 1437141.3 - https://www.icao.int/environme...2019/ENVReport2019_pg66-71.pdf
Data Source: un
Aircraft Noise Annoyance CHAPTER TWO Aircraft Noise 89 RECENT DEVELOPMENTS Researchers have tried for half a century to identify predictive statistical relationships between transportation noise exposure levels and human annoyance levels. (...) At a noise level of Ldn = 55 dB, the prevalence of highly annoyed varies between 0 % and 90 %. (...) At equal noise levels, the annoyance has been observed to increase with an increasing number of movements.
Language:English
Score: 1432304.6 - https://www.icao.int/environme...2019/ENVReport2019_pg89-92.pdf
Data Source: un
AEROPLANE CERTIFICATION PROCEDURES Aeroplane acoustic certifi cation involves measuring the noise level of an aircraft in Effective Perceived Noise Level (EPN) dB2 at three reference points: Fly-over: 6.5 km from the brake release point, under the take- off fl ight path; Sideline: the highest noise measurement recorded at any point 450 m from the runway axis during take-off; Approach: 2 km from the runway threshold, under the approach fl ight path. (...) The progression of the ICAO Noise Standard. As a result of the new Chapter 14 noise Standard, it is expected that the number of people affected by significant aircraft noise will be reduced, and that more than one million people could be removed from “Day Night average sound Level (DNL) of 55 dB affected areas” between 2020 and 2036. (...) The goal of the procedures formulation effort is to establish technical flight test procedures for supersonic noise certification. These would be in addition to the certification requirements for the subsonic local airport conditions, where the maximum noise levels that would be applicable to subsonic jet aeroplanes would likely be used.
Language:English
Score: 1419779.3 - https://www.icao.int/environme...2016/ENVReport2016_pg27-29.pdf
Data Source: un
Over the past century many anthropogenic marine activities have increased levels of noise (Hildebrand 2009; André et.al. 2010; Miksis-Olds and Nichols 2016) These modern anthropogenic noises have the potential for physical, physiological and behavioural impacts (Southall et.al. 2007). 6. (...) The aim is to model the received sound levels at given distances from the noise source. The amount of sound lost at the receiver from the sound source is propagation loss. 22. (...) III.5. Sound Exposure Level cumulative (SELcum) 26. Sound Exposure Level (SEL) is generally referred to as dB 0 to peak or peak to peak (dB 0 to peak or dB p to p) for impulsive noise like air guns or pile driving, and dB Root Mean Squared (dBrms) for non-impulsive noise such as ship noise, dredging or a wind farm’s constant drone.
Language:English
Score: 1409135.8 - https://www.un.org/Depts/los/g...ft_guidelines_marine_noise.pdf
Data Source: un
APPENDIX D Phase-out of subsonic jet aircraft which exceed the noise levels in Volume I of Annex 16 Whereas certification standards for subsonic jet aircraft noise levels are specified in Volume I of Annex 16; Whereas for the purpose of this Appendix, a phase-out is defined as withdrawal of a noise-based category of aircraft from international operations at all airports in one or more States; Whereas the Committee on Aviation Environmental Protection has concluded that a general phase-out of Chapter 3 aircraft operations by all the countries which imposed a phase-out on operations of Chapter 2 aircraft is not supported on cost-benefit grounds; Whereas some States have implemented or initiated phase-outs of aircraft which exceed the noise levels in Volume I, Chapter 3 of Annex 16, or are considering so doing; Recognizing that the noise standards in Annex 16 are not intended to introduce operating restrictions on aircraft; Recognizing that operating restrictions on existing aircraft may increase the costs of airlines and could impose a heavy economic burden, particularly on aircraft operators which may not have the financial resources to re-equip their fleets, such as those from developing countries; and Considering that resolution of problems due to aircraft noise must be based on the mutual recognition of the difficulties encountered by States and a balance among their different concerns; The Assembly: 1. (...) Urges States not to introduce any operating restrictions at any airport on aircraft which comply with Volume I, Chapter 3 of Annex 16 before: a) completing the phase-out of aircraft which exceed the noise levels in Volume I, Chapter 3 of Annex 16, at the airport concerned; and b) fully assessing available measures to address the noise problem at the airport concerned in accordance with the balanced approach described in Appendix C; 3. (...) Urges States that have phased out operations of Chapter 2 aircraft at their airports as provided for in Appendix D to this Resolution, whilst preserving the benefits for local communities to the greatest extent practicable, to avoid inappropriate land use or encroachment whenever possible in areas where reductions in noise levels have been achieved; 2. Urges States to ensure that the potential reductions in noise levels to be gained from the introduction of quieter aircraft, particularly those complying with the new Chapter 4 standard, are also not avoidably compromised by inappropriate land use or encroachment; 3.
Language:English
Score: 1401374.5 - https://www.icao.int/Meetings/...%2036th%20Session/wp035_en.pdf
Data Source: un
Anthropogenic underwater noise and its impacts have received increasing attention from various intergovernmental fora at the global and regional levels. (...) Offshore wind farms construction undertaken using impact pile driving creates low-frequency noise at relatively high source levels, while their operation produces moderate source levels, with additional noise generated by maintenance and repair work. (...) Several technologies aiming to reduce sound levels or mitigate noise impacts have been developed in recent years.
Language:English
Score: 1399410.2 - https://www.un.org/Depts/los/c...ative_process/icp19_report.pdf
Data Source: un
Evidence of ubiquitous noise-like emissions The cooperation with CENELEC coincided with increasing concerns that nearly all items of electronic and electrical equipment were radiating significant amounts of noise-like emissions as well as feeding back RF energy into the mains wiring The common element identified is use of high speed switching in the power supplies and power conversion stages almost universal nowadays in every item of equipment RF noise in the 7.8-8.3 MHz range RF noise effects The liaison with CENELEC proved particular useful in highlighting the problems caused by increasing RF noise levels Their studies have reveal that RF noise on mains wiring can affect connected equipment in a variety of unexpected ways. In effect, nearly all items of electrical and electronic equipment could be both sources of mains borne RF noise and victims of various noise induced disturbance mechanisms There have, for example, been instances of microprocessor controlled equipment carrying out uncommanded actions Re-focus on interference studies in Study Group 1 Cooperation with CENELEC has influenced the work in WP1A, steering it more towards the long term risk to all radiocommunication services coming from increasing levels of RF noise in the environment WP1A therefore started a campaign to gather evidence on the prevalence and impact of RF noise from other Working Parties and stakeholder groups. These efforts have been supplemented by work in ITU-R by WP 1C and WP3L to measure, characterize and predict RF noise levels in the environment Impact of mains borne RF noise RF noise on mains wiring has be found to reduce the lifetime of filter components in switch mode power conversion stages through overheating, and resulting in more RF feeding back on the mains wiring, which then causes the same failures in other connected devices and so on – a vicious circle of degradation The most alarming effects discovered were with LED lighting systems and units.
Language:English
Score: 1396123.9 - https://www.itu.int/en/ITU-R/s...ivities%20WP6A_John%20Shaw.pdf
Data Source: un
As a result, the acoustic noise affecting the amateur radio decreased slightly, but still remained. 3) Search technique 2 (to find the noise source) When a noise is emitted, there must be both a noise source and a noise radiator. Both elements were searched for. a) The system was measured in an anechoic chamber and the noise level was checked. b) The noise source was searched for using a near-field magnetic probe and a spectrum analyser, as shown in Figure 1.4-2. (...) Areas close to board components IC8 and Xtal4 had higher noise levels. c) The noise level was checked by trial and error in an anechoic chamber when a mitigation device such as a capacitor or ferrite core was installed.
Language:English
Score: 1396122.3 - https://www.itu.int/wftp3/Publ...tigation-part2-merged-E_19.pdf
Data Source: un
As a result, the acoustic noise affecting the amateur radio decreased slightly, but still remained. 3) Search technique 2 (to find the noise source) When a noise is emitted, there must be both a noise source and a noise radiator. Both elements were searched for. a) The system was measured in an anechoic chamber and the noise level was checked. b) The noise source was searched for using a near-field magnetic probe and a spectrum analyser, as shown in Figure 1.4-2. (...) Areas close to board components IC8 and Xtal4 had higher noise levels. c) The noise level was checked by trial and error in an anechoic chamber when a mitigation device such as a capacitor or ferrite core was installed.
Language:English
Score: 1396122.3 - https://www.itu.int/wftp3/Publ...gation/WebSearch/page0019.html
Data Source: un
Noise levels in the Slovenian sea are influenced mainly by marine traffic, coastal construction and tourism. (...) The Slovenian sea is very shallow, so that reflections of noise from the seafloor and the sea surface (echo), add up to noise levels higher than those from the actual noise input. (...) The proposal aims at stronger coordination between member states that share marine regions and sub- regions, in order to increase the conservation status and the level of protection of the marine species of the Mediterranean Sea against damage caused by the underwater noise resulting from anthropogenic activities.
Language:English
Score: 1395542.8 - https://www.un.org/Depts/los/g...files/SLOVENIA_ocean_noise.pdf
Data Source: un