Operating restrictions can be partial, global or progressive and may be classified in two categories:
(a)
Restrictions of traffic such as night curfews, or a cap on movements or noise energy.(b)
Restrictions on the use of aircraft with a particular noise, technical, or performance characteristic.Ground Measures, although covered under the principal elements of the Balanced Approach, are generally considered and implemented separately. They can include, but are not limited to, the following measures:
(a)
Limitation of engine ground running.(b)
Designated areas for engine ground running.(c)
Minimised APU operation.(d)
Minimised taxi times and routing.(e)
Noise barriers.E3.2.2 Noise Assessment
The noise assessment should identify the level of noise from the airport to which the nearby community
is exposed. Whether a noise 'problem' exists depends on whether noise is worsening based on the particular standard that the airport and/or the competent authority in which it resides currently employ.
The noise-related standard, or noise objective that is meant to be achieved, should be identified and defined before the assessment is to begin. The baseline is the noise situation currently experienced by the community surrounding the airport and projected into defined points in the future, taking into account existing plans without revising current mitigation measures or providing additional measures.
If the baseline noise situation does not meet the noise objective that has been identified, a noise problem may be determined to exist. Under the balanced approach program, in such a case, possible
new or revised noise mitigation measures under the elements of the balanced approach — sometimes
referred to as 'action scenarios' — would be considered.
To determine whether any such measure under an 'action scenario' might improve the noise situation,
the competent authority or airport undertaking the assessment would compare the baseline noise situation with the noise situation that would occur were the new or revised measures adopted. In light of the many factors contributing to the noise situation at a particular airport, methods to measure the noise from single aircraft events or single points in time are not considered to describe the noise situation at an airport. Instead, a noise index or equivalent parameter, comprised of aggregated noise information, often is recommended. Although a calculated noise index for a particular
airport is a means of reflecting noise information, by itself it is not considered sufficient to describe the noise situation at the airport. Usually one would want to place the information from the calculated
noise index into a larger context, so that the exposure of people to significant levels of noise may be assessed over a given time period (preferably at least one year). One way of determining the
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Noise Monitoring: Although noise annoyance generally is a subjective matter, it is recognized that the noise surrounding an airport should be assessed based on objective, measurable criteria and other relevant factors.
The noise at points on the ground, caused by aircraft flying into and out of a nearby airport, depends on a number of factors. These include the types of aircraft using the airport, the overall number of takeoffs and landings, the time of day the aircraft operations occur, the runways that are used, weather
conditions, and airport-specific flight procedures that affect the noise produced. Single, point-in-time noise measurements cannot be expected to represent the overall noise situation at an airport. Instead,
noise monitoring and/or noise modelling may be necessary.
To the extent noise monitoring is used, it should be undertaken over time to reflect noise at the airport
under different conditions. A one-year monitoring period would be expected to provide noise data that is representative of the periodicity of the traffic schedule, operational characteristics such as payload changes, and meteorological data. The noise monitoring equipment should be capable of capturing noise from aircraft alone, or a method should be employed for screening out non-aircraft noise. Placement of noise monitors at different distances can identify noise energy in different areas around the airport. However their placement should not be nearer to the airport than as defined for noise certification in order to ensure at least proper measurement at the three-certification points.
Identification and Assessment of Measures: When identifying the noise problem at an airport and
analyzing the various measures available to reduce noise through the exploration of the four principal elements of the Balanced Approach (noise reduction at source, land-use planning and management, noise abatement operational procedures and operating restrictions), the goal is to address the noise problem using objective criteria in the most cost-effective manner.
On implementing the concept of the balanced approach to noise management, particular attention shall be given to the principal elements and the analytical and methodological tools that might be needed to assess and compare those elements. Steps taken by airports to address local noise issues
should be consistent with the principal elements and ensure that the relationship between them — in particular in the area of noise and emission trade-offs, the impact of short term versus long term solutions, as well as local versus regional solutions — are fully addressed.
Environmental benefits (in terms of reduction of numbers of inhabitants severely affected by noise) associated to the measures considered should then be compared to their respective cost of implementation through the use of the cost-effectiveness analysis methodology. The measures will be ranked both by potential environmental benefits and cost of implementation. For each measure this will enable the definition of a unit cost per inhabitant that will not be further affected by noise in the future.
This process will provide stakeholders with an assessment of benefits and costs associated with each of the measures being considered. The appropriate measure, or a combination of appropriate measures, should then be chosen from among the measures assessed, in consideration of the objectives set forth at the beginning of the process.
Transparent Process: When developing or updating a noise mitigation program there is a need for
a transparent process which will include, but is not necessarily limited to, the following:
(a)
Assessment of the noise situation including the evolution of the problem and expectedimprovements resulting from current measures and fleet renewal.
(b)
Definition of the noise objectives.IATA
Environmental Issues
(e)
Cost effectiveness analysis of the available measures.(f)
Selection of measures with the goal to achieve maximum environmental benefits most cost effectively.(g)
Notification and coordination in the implementation of measures. (h) Dispute resolution for stakeholders.E3.3 IATA RECOMMENDATIONS
E3.IR1 Noise Abatement Policy
Although noise annoyance is a subjective matter and noise mitigation programs are well established at many international airports, IATA recommends that airports, when assessing tbait noise climate for either updating existing measures or for the introduction of new measures, take into account the methodology for the Balanced Approach. In addition, IATA re-emphasises the ICAO policy in Resolution A33-7 where States have agreed not to permit the introduction of any operating restrictions aimed at the withdrawal of aircraft that comply with the noise standards in Volume I, Chapter 4 of Annex 16.
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SECTION E4: EMISSIONS E4.1 INTRODUCTION
Airport emissions affect the environment in a variety of ways, most of them on a local scale. Aircraft landings and takeoffs, taxiing, ground handling, maintenance, power generation, office buildings and
road traffic at and around the airport all contribute to the airport's environmental footprint. Efforts to reduce the airport's overall impact should, therefore, ideally address all sources in a balanced way.
E4.2 AIRPORT EMISSIONS FROM AIRCRAFT
In the immediate vicinity of airports, aircraft emissions of nitrogen oxides (NOx) unburned
hydrocarbons
(HC), carbon monoxide (CO) and particulate matter (PM, including visible smoke) contribute to local air quality concerns. The effects on local air quality of other minor trace species such as sulphur dioxide (S02), hydroxyl radicals (OH), nitrous and nitric acids, and chemi-ions are negligible and
mostly poorly understood. In spite of the relatively low levels, airport emissions are increasingly linked
to respiratory health problems among the local population.
As with noise, ICAO's international certification regime for aircraft emissions has brought about significant improvements in the emissions performance of aircraft through the progressive tightening of standards. Since the 1960s, emissions of HC, CO and smoke from aircraft have come down by at least 90%, to the extent that further mitigating efforts are no longer seen as a priority by regulators.
The combustion conditions required to achieve these reductions as well as noise reductions have, however, led to a simultaneous increase in NOx emissions.
International emission standards for the certification of turbo-jet and turbo-fan engines were first introduced by ICAO in June 1981, and published as Volume II of Annex 16 to the Chicago Convention.
The ICAO standard-setting process is important to the industry because it maintains consistency in manufacturers' and carriers' requirements around the world. In 1993 ICAO subsequently increased the NO, stringency limit by 20% (effective 1995) and by another 16% in 1999 (effective 2004). ICAO's
Committee on Aviation Environmental Protection (CAEP) is currently evaluating the potential for a further increase in NOx stringency for new engines.
Additional reductions in aircraft NOx emissions require careful development and deployment of more
complex and more expensive combustor designs. Major industry research programmes focus on NOx
reductions of 70% for future aircraft within 10 years, and 80% within 25 years. These efforts will help to meet new NOx standards in the future, such as the European Union limits regarding NOx
emissions
around Community airports, expected to come into force in 2010.
Besides the continuous introduction of new engine technologies in their fleets (like, for example, the DAC engine), airlines further minimise ground level emissions through a variety of operational techniques, such as one-engine taxiing, being towed instead of taxiing, minimal APU-use, pilot shut- down of engines during ground delays, and delayed engine start.
As a consequence of the steadily growing number of aircraft movements at airports around the world,
authorities are, however, increasingly obliged to respond to local public and political pressures to curb airport activities. For this reason, local NOx emissions are quickly emerging as a potential