The IFATCA Technical and Operations Committee (TOC) was tasked to review IFATCA Policy on environmental issues in ATM. TOC has decided to produce two working papers; one that deals with IFATCA Policy (B.5.9) and this working paper which will provide an update on currently known facts, will list relevant ICAO Regulations, will address new developments, techniques, procedures, research (including Global Warming) and its impact on ATC. The information and conclusions provided with this paper could assist civil aviation authorities, Air Navigation Service Providers (ANSPs) and Member Associations (MAs) in finding an acceptable balance between safety and environment, especially when new techniques and procedures are implemented solely for environmental reasons.This paper must be read as an individual paper but does also provide additional background information on the review of related policy. This working paper is information material.

1.1.  Since the second part of the last century, preserving the environment is an important issue to human existence. There are several environmental issues in Air Traffic Management (ATM). Aircraft noise and aircraft emissions are issues that have the greatest environmental impact. Therefore noise abatement and improving Local Air Quality (LAQ) has the highest priority on the environmental agenda of ICAO. For this reason these two issues, and their impact on Air Traffic Control (ATC), will be addressed by this paper.

1.2.  The objective is to provide a clear, impartial and comprehensive information paper containing all relevant information about current environmental issues in ATC. There is a huge source of information available on the Internet, in books, magazines and ICAO documents. Although there is disagreement on global warming and the assumed effects for climate change, the Technical and Operations Committee (TOC) has tried to provide IFATCA with an objective presentation of all known facts via this working paper.

1.3.  TOC has been tasked to provide a follow up regarding preceding working papers concerning environmental issues in ATC. TOC has decided to draft a separate paper on reviewing IFATCA policy in this matter (B.5.9).

2.1 ICAO

2.1.1  ICAO is conscious of its responsibility and that of its contracting States; “to achieve maximum compatibility between the safe and orderly development of civil aviation and the quality of the environment” (Assembly Resolution A35-5). ICAO activities on the environment are primarily focused on those problems that have the largest impact, namely aircraft noise and aircraft engine emissions. ICAO current environmental activities are largely undertaken through the Committee on Aviation Environmental Protection (CAEP), which was established by the Council in 1983, superseding the Committee on Aircraft Noise (CAN) and the Committee on Aircraft Engine Emissions (CAEE). ICAO cooperates closely with other United Nations (UN) organizations dealing with the environment, notably with the United Nations Framework Convention on Climate Change (UNFCCC) and the Intergovernmental Panel on Climate Change (IPCC).

2.1.2  Each formal CAEP meeting produces a report with specific recommendations for the consideration of the ICAO Council. In the seventh meeting of the CAEP the following recommendations were made:

• New Standards and Recommended Practices (SARPs) for Annex 16 Environmental Protection, Vol.1;
• New guidelines on the use of procedures in the emissions certification of aircraft engines;
• New mid and long-term technology goals for NOx;
• New airport air quality guidance manual;
• New ICAO Circular on noise and emission effects from National Atmospheric Deposition Programs (NADP);
• New report on voluntary emissions trading for aviation;
• New draft emissions trading guidance;
• New Local Air Quality (LAQ) emission charges guidance; and
• Changes to the ICAO policy on charges for airports and air navigation services. 

No new standards for aircraft noise were proposed at CAEP/7. Additional technical information for the ICAO Doc 9501 Environmental Technical Manual on the Use of Procedures in the Noise Certification of Aircraft was developed and the document will be updated accordingly.

2.1.3  ICAO provides guidance material, ‘Operational Opportunities to Minimize Fuel Use and Reduce Emissions’ (Circular 303), for States so as to enable airports, airlines and other stakeholders that have successfully reduced emissions to share their techniques with others. ICAO has set certification standards for engines to reduce emissions from aviation. These are contained in Annex 16 Environmental Protection to the Convention on International Civil Aviation and were originally designed to respond to concerns regarding air quality in the vicinity of airports. As a consequence, they establish limits for emissions of oxides of nitrogen (NOx), carbon monoxide, unburned hydrocarbons. In order to reduce aircraft noise, ICAO has set (in Annex 16 Environmental Protection ) requirements for the manufacturing of airplanes and helicopters to meet noise certification standards.

2.1.4 Aviation was the first sector to request the IPCC to prepare a full assessment of the Impact of its activities. An assessment of aviation’s estimated impact on the atmosphere is contained in the “Special Report on Aviation and the Global Atmosphere”, which was prepared at ICAO’s request by the IPCC, in collaboration with the Scientific Assessment Panel to the “Montreal Protocol on Substances that Deplete the Ozone Layer” and was published in 1999.

2.2 General

2.2.1  IFATCA addresses environment in the ’Statement on the future of global ATM’:

“This relates to, gaseous emissions noise, visual intrusion, etc. Each member of the ATM community is individually responsible for behaving in an environmentally responsible manner. It could therefore be argued that if the airspace user flies their requested 4-d trajectory without modification that they would therefore be responsible for all environmental consequences of that flight –however this is too simplistic as the combination of all ATM activities is a community activity and there will be a level of shared commitment, collaboratively agreed, to the ATM system operating in an environmentally sustainable way.”

2.2.2  Aviation contributes to global warming in a number of ways; the most significant is the emission of greenhouse gases by combustion of kerosene in flight. The principal greenhouse gas emission from aircraft in flight is carbon dioxide (CO2), but other emissions include nitric oxide and nitrogen dioxide, water vapour and particulates.

2.2.2.1  Carbon dioxide (CO2) emissions

CO2 emissions from aircraft-in-flight are the most significant and best understood element of aviation’s total contribution to climate change. The level and effects of CO2 emissions are currently believed to be broadly the same regardless of altitude (i.e they have the same atmospheric effects as ground based emissions). Emissions of CO2 from aircraft is estimated at around 3% of all such anthropogenic emissions.

2.2.2.2  Oxides of nitrogen (NOx) induced effects

At altitude, emissions of NOx are particularly effective in forming ozone (O3) in the upper troposphere. High altitude (8-13km) NOx emissions result in greater concentrations of O3 than surface NOx emissions, and these in turn are thought to have a greater global warming effect. The effect of O3 concentrations are regional and local (as opposed to CO2 emissions, which are global).

2.2.2.3  Water vapour induced effects

Aircraft-in-flight emit water vapour, a greenhouse gas, which under certain atmospheric conditions forms condensation trails or contrails. Contrails are visible line clouds that form in cold, humid atmospheres and are thought to have a global warming effect (though one less significant than either CO2 emissions or NOx induced effects).

Contrails

Cirrus cloud formation

2.2.3  Calculating the total climate change effect

In attempting to aggregate and quantify these effects the IPCC has estimated that aviation’s total attribute to global warming is some 2-4 times that of its CO2 emissions alone. This is measured as radiative forcing. The origin of climate metrics lies in the physics of the phenomenon of climate change. The basic property that is affected by ‘greenhouse gases’ is the energy balance (radiative balance) of the atmosphere. This is the balance between incoming short-wave solar radiation and outgoing long-wave infrared radiation.

While there is uncertainty about the exact level of impact of NOx and water vapour, governments have accepted the broad scientific view that they do have an effect. Accordingly, more recent government policy statements have stressed the need for aviation to address its total climate change impacts and not simply the impact of CO2. The IPCC has estimated that aviation is responsible for around 3.5% of anthropogenic factors, a figure which includes both CO2 and non-CO2 induced effects. The IPCC has produced scenarios estimating what this figure could be in 2050. The central case estimate is that aviation’s contribution could grow to 5% of the total contribution by 2050 if action is not taken to tackle these emissions, though the highest scenario is 15%. Moreover, if other industries achieve significant cuts in their own greenhouse gas emissions, aviation’s share as a proportion of the remaining emissions could also rise.

2.2.4  Aviation and the Kyoto Protocol

Greenhouse gas emissions from fuel consumption in international aviation, in contrast to those from domestic aviation and from energy use by airports, are not assigned under the first round of the Kyoto Protocol, neither are the non-CO2 climate effects. In place of agreement, Governments agreed to work through ICAO to limit or reduce emissions and to find a solution to the allocation of emissions from international aviation in time for the second round of Kyoto in November 2007.

2.2.4.1 Aviation and emissions trading

As part of that process ICAO has endorsed the adoption of an open emissions trading system to meet CO2 emissions reduction objectives. Guidelines for the adoption and implementation of a global scheme have been further developed, and have also been presented to the ICAO Assembly in 2007, although the prospects of a comprehensive intergovernmental agreement on the adoption of such a scheme are uncertain.

2.2.5  According to the IPCC, stated in earlier assessment reports, there is a climate change in progress due to global warming on account of anthropogenic factors, mainly the increase of greenhouse gases. Other scientists challenge this statement, they claim that the present climate change is merely a normal action caused by nature. In their opinion the contribution of anthropogenic factors in this process are to neglect. These scientists claim that solar activity is mainly responsible for the global warming despite the production of greenhouse gases by man. According to these scientists nature itself produces the majority of greenhouse gases and are believed not to be the result, but the reaction of global warming. Global warming is, according to these scientists, the cause for oceans to produce the main part of CO2 emissions.

2.2.6  Despite the question if and by what degree man is responsible for global warming, which causes climate to change, reduction of manmade emissions of greenhouse gases is absolutely required. Beyond the need for reduction of manmade emissions there is the absolute fact that mankind is running out of fuel. Especially this last fact is of the highest importance to aviation. A large percentage of commercial aviation currently uses kerosene as fuel, currently no alternative has been identified.

2.2.7  Potential for emissions reductions and increasing efficiency

Modern aircraft are significantly more fuel efficient (and thus emit less CO2 in particular) than 30 years ago. Moreover, manufacturers have forecasted and are committed to achieving reductions in both CO2 and NOx emissions with each new generation of design of aircraft and engine. The accelerated introduction of more modern aircraft therefore represents a major opportunity to reduce emissions per passenger kilometre flown. Other opportunities arise from the optimisation of airline timetables, route networks and flight frequencies to increase load factors, together with the optimisation of airspace. Collaborative Decision Making (CDM) and projects like Single European Sky ATM Research (SESAR) are examples of initiatives in this perspective. The Eurocontrol Performance Review Commission (PRC) has calculated that current en route emissions per flight could be reduced by 6% by optimising flight efficiency. Single European Sky (SES), 4D Trajectory Concepts (WP B.5.2) and SESAR are initiatives that could provide an improved ATM system. In the long-term, potential radical new airspace management techniques could allow aircraft to be routed to avoid climate- sensitive parts of the sky, where contrails would be produced. However, this remains a complex area with many uncertainties, and would not eliminate CO2.

2.2.8  Presently the required standards of ICAO regarding aircraft emissions have little impact to the operations of ATC. Airlines, aircraft manufacturers and airports are much more directly influenced by these ICAO requirements. However, ATC is likely to expect these stakeholders to enforce more efficiency and higher capacity for economic and environmental reasons.

2.3 Aircraft noise

2.3.1 Beside the effect of aviation to global warming the aspect of aircraft noise is as an important environmental issue. Aircraft noise is defined as sound produced by any aircraft on run-up, taxiing, take off, over-flying or landing. Aircraft noise is a significant concern for approximately 100 square kilometres surrounding most major airports. Aircraft noise is the second largest (after roadway noise) source of environmental noise. While commercial aviation produces the preponderance of total aircraft noise, private aviation and military operations also play a role. It is usually measured in Decibels. Take-off of aircraft may lead to a sound level of more than 100 decibels at the ground, with approach and landing creating lower levels. Since aircraft landing in inner-city airports are often lower than 60 meters above roof level, a sound level above 100 dBA can be realized.

2.3.2 The annoying effects of aircraft noise are widely recognized. Studies in the U.S.A. from Centers for Disease Control and Prevention (CDC) and the National Center for Environmental Health (NCEH) have concluded that aircraft noise is also responsible for a significant amount of hearing loss as well as a contributor to a number of diseases. High levels of aircraft noise that commonly exist near major commercial airports are known to increase blood pressure and contribute to hearing loss. Research has indicated that aircraft noise contributes to heart diseases, immune deficiencies, asthma and other stress related diseases. Further research is being carried out to better understand these effects.

2.4 Applications

2.4.1  ICAO has provided guidance material to reduce the effect of aircraft noise. ICAO guidance on this subject is contained in Annex 16 Environmental Protection.

In 2001, the ICAO Assembly endorsed the concept of a “balanced approach” to aircraft noise management (Appendix C of Assembly Resolution A35-5). This consists of identifying the noise problem at an airport and then analyzing the various measures available to reduce noise through the exploration of four principal elements, namely:

1. reduction at source (quieter aircraft),
2. land-use planning and management,
3. noise abatement operational procedures, and
4. operating restrictions.

This with the goal of addressing the noise problem in the most cost-effective manner. ICAO has developed policies on each of these elements, as well as on noise charges.

2.4.2  Land-use Planning and Management

Land-use planning and management is an effective means to ensure that the activities nearby airports are compatible with aviation. Its main goal is to minimize the population affected by aircraft noise by introducing land-use zoning around airports. Compatible land-use planning and management is also a vital instrument in ensuring that the gains achieved by the reduced noise of the latest generation of aircraft are not offset by further residential development around airports.

2.4.3  Noise Abatement Operational Procedures

Noise abatement procedures enable reduction of noise during aircraft operations to be achieved at comparatively low cost. There are several methods, including preferential runways and routes, as well as noise abatement procedures for take-off, approach and landing. The appropriateness of any of these measures depends on the physical lay-out of the airport and its surroundings, but in all cases the procedure should give priority to safety considerations. The use of noise abatement procedures in take off and landing are used all over the world. Standard Instrument Departure (SID) and Standard Arrival Route (STAR) are the most common tools used to avoid excessive noise while over flying populated areas. Furthermore are Continuous Descent Approaches (CDAs), that offer environmental benefits in the form of reduced noise and a decrease in emissions. Studies have highlighted CDA as the leading technique for reducing arrival noise, for more detail on CDAs, see also working paper 85/2006.

2.4.4 Operating Restrictions

Noise concerns have led some States to consider banning the operation of certain noisy aircraft at noise-sensitive airports. In the 1980s, the focus was on Noise Non Certificated (NNC) aircraft; in the 1990s, it moved to Chapter 2 (ICAO Noise Certification Standards, as described in Annex 16 Environmental Protection) aircraft; today, it has moved to the noisiest Chapter 3 aircraft. However, operating restrictions of this kind can have significant economic implications for the airlines concerned, both those based in the States taking action and those based in other States that operate to and from the affected airports. On each occasion, the ICAO Assembly succeeded in reaching an agreement – contained in an Assembly resolution – that represented a careful balance between the interests of developing and developed States and took into account the concerns of the airline industry, airports and environmental interests.

2.5 Noise legislation

2.5.1  In Europe, some governments control noise by imposing noise level conditions and restrictions. By means of calculating and measuring civil aviation authorities can control the maximum limit of noise level for a particular aerodrome. These noise limits are strictly enforced and the authorities may even impose severe sanctions if limits are exceeded. Such sanctions could for example consist of a very substantial fine for the Air Navigation Service Provider (ANSP), temporary closure of a runway or a reduction in the number of aircraft movements, causing considerable economic damage to the airport and in particular to the airlines involved.

2.5.2  With six runways and over fifty departure routes and handling about 460.000 aircraft movements per year, Amsterdam Schiphol Airport is subject to probably one of the most complex noise legislation in the world. The number of yearly aircraft operations is limited due to the noise limits by 60 enforcement points, making it necessary to manage the operation within the available “noise space” as efficiently as possible. Schiphol has developed a model to accurately forecast the fleet distribution over all runway-route combinations, based on different operational usages of the airport. In addition a model was developed that maximizes the number of aircraft movements within set noise limits, based on optimizing the noise loads that result from different operational usages of the airport, using genetic algorithms. This model enables the Dutch aviation sector to make ongoing decisions on the moment and type of operational measures to be taken in order to both maximize the yearly airport capacity, as well as quantifying and minimizing the risk of exceeding set noise limits in that year.

2.5.3  This noise legislation is also known for some negative side effects. When the maximum amount of noise set for one runway is or is about to be reached, less preferential runways have to be used. This might mean using a runway with more cross- or tailwind.

2.5.4 In 1997 there was a landing-accident at Schiphol. One of the causes of this accident was the runway-allocation at that time, which prescribed the use of the most noise preferential runway up to a maximum of 25 Kts crosswind during night hours. At that time, several runways had been closed as the total computed amount of noise was reached. This resulted in the use of a less preferential runway.

In 2001 an aircraft crashed at Zurich airport while executing a non-precision approach. A precision approach on another runway could not be performed as a result of environmental restrictions. It cannot be said that this accident forced the local authorities to install a precision approach for this particular runway, it was also not mentioned in the incident report, but it is a fact that the precision approach has now been installed.

These two examples clearly indicate that safety can be affected because of environmental concerns.

2.6 United Kingdom

2.6.1 In 2004 the UK Civil Aviation Authority (CAA) did research on the safety issues related to environmental restrictions. The aim was to answer the question: “Are there any instances where the desire to promote environmental benefits raises real problems about the safety assurance being provided operationally?”.

2.6.1.1  Seven types of environmental constraint at an airport were examined:

a) CDA;

b) Low Power Low Drag (LPLD);

c) Use of ‘non-precision’ runways;

d) Crosswind component;

e) Tailwind component;

f) Noise abatement take-off procedure; and

g) Noise Preferential Routeing (NPR).

2.6.1.2  According to the outcome of the study there were three problem areas where there were reasoned concerns:

a)  “The evidence is that the use of non-precision approaches solely for environmental reasons is unwise. This is a policy conclusion not a requirement for any further work.”

b)  “It is important to demonstrate that NPRs can be flown safely, i.e. they are within normal operational conditions and fully under the pilot’s control, immaterial of the type of aircraft using the NPR.”

c)  “The acceptability of workload under CDAs needs to be demonstrated.”

Furthermore the study concluded that an agreed and clearly stated safety methodology has to be employed when assessing environmental with Joint Aviation Authorities (JAA) guidelines and suitable for practical use should be developed. The study also stressed that the UK’s national Department for Transport Guidance was in no way equivocal about the priority of safety in decision-making: it certainly never suggested that the achievement of safety could ever be ‘traded off’ against other goals.

2.7 Noise Abatement Operational Procedures

2.7.1  Noise abatement operational procedures are being employed today to provide noise relief to communities around airports from both arriving and departing aircraft. ICAO Doc 8168 Aircraft Operations, Volume 1, contains guidance for the development Noise Abatement Departure Procedures (NADPs). NADPs are generally designed to mitigate noise either close in to the airport, or further out along the departure path.

Noise abatement operations procedures in use today can be broken down into three broad categories:

2.7.2  Noise abatement flight procedures

Continuous Descent Approach (CDA)

A CDA is an aircraft operating technique in which an arriving aircraft descends from
an optimal position with minimum thrust and avoids level flight to the extent permitted by the safe operation of the aircraft and compliance with published procedures and ATC instructions. The noise benefit arises from reduced thrust and higher altitude of the aircraft and is substantial. The proportion of aircraft achieving CDA will depend on local traffic conditions and the local airspace characteristics, and in a high density traffic area development and implementation of supporting planning and arrival tools maybe necessary.

Noise Abatement Departure Procedures (NADP)

NADPs, published in ICAO Doc 8168 Aircraft Operations, allow for benefits in areas either close-in or at distances further from the airport. Such procedures make better use of the improved performance of modern Chapter 3 aircraft. Several types of noise abatement departure procedures have been adopted to reduce the impact on sensitive areas. They generally involve a thrust reduction after a first segment at take-off power/thrust. Reduction of noise levels to the side of and at the beginning of a runway can be achieved by displacing the commencement of the take-off, but at the expense of increased noise exposures under the flight path.

Modified approach angles, staggered, or displaced landing thresholds. Minor adjustments in aircraft approach profiles can achieve considerable benefits in noise abatement.

Low power/low drag approach profiles (LPLD)

LPLD is a noise abatement technique for arriving aircraft in which the pilot delays the extension of wing flaps and undercarriage until the final stages of the approach, subject to compliance with ATC speed control requirements and the safe operation of the aircraft. In LPLD, the aircraft is flown at the highest safe speeds, with aircraft configuration as ‘clean’ as possible.

Minimum use of reverse thrust after landing

Landing Distance Available (LDA) and other (weather) conditions permitted, minimum use of reverse thrust after landing is an option to reduce noise.

2.7.3 Spatial management

Noise preferred arrival and departure routes (NPR)

Historically, SID and STAR development was based upon the ground infrastructure of navigation aids. The location of these aids (VORs and DMEs) depended on suitable sites and the need to avoid flying, as far as possible, over populated communities. Governments and ATC bodies therefore produced what were once known as Minimum Noise Routes – now termed NPR. These are specific ground tracks, which map on to the SID structure – the NPR is essentially the first part of the SID. By careful choice of NPR/SID/STAR, aircraft tracks can be moved up to several miles away from a sensitive community – producing very large reductions in noise impact.

Flight track dispersion or concentration

Track dispersion to spread the level of noise can be a successful method. On the other hand track concentration will prevent aircraft to overfly noise sensitive areas.

Noise preferred runways

A runway for take-off or landing appropriate to the operation, may be nominated for noise abatement purposes. In ICAO Annex 6 Operation of Aircraft, ICAO has published requirements, regarding maximum cross-wind and tail-wind components, for operations with noise preferential runway selection. According to ICAO runways should not be selected for noise abatement purposes for landing operations unless they are equipped with suitable glide path guidance, e.g. Instrument Landing System (ILS), or a visual approach slope indicator system for operations in visual meteorological conditions. Limits for cross-wind and tail-wind and other factors which determine the runway nomination are also set in Doc 8168 Aircraft Operations, and ICAO Doc 4444 Air Traffic Management. These limits have accordingly consequential effect for the reporting requirements stated in Annex 3 Meteorological Service for International Air Navigation. ICAO has recently amended the requirements for the use noise preferential runways in Doc 4444 Air Traffic Management. In this amendment, ICAO clearly states that runways should not be selected for noise abatement purposes for landing operations unless they are equipped with suitable glide path guidance, e.g. ILS, or a visual approach slope indicator system for operations in visual meteorological conditions.

“Noise abatement shall not be a determining factor in runway nomination under the following circumstances:

a)  if the runway surface conditions are adversely affected (e.g. by snow, slush, ice, water, mud, rubber, oil or other substances);

b)  for landing in conditions: when the ceiling is lower than 150 m (500 ft) above aerodrome elevation, or the visibility is less than 1 900 m; or when the approach requires use to be made of vertical minimums greater than 100 m (300 ft) above aerodrome elevation and: the ceiling is lower than 240 m (800 ft) above aerodrome elevation; or the visibility is less than 3 000 m;

c)  for take-off when the visibility is less than 1 900 m;

d)  when wind shear has been reported or forecast or when thunderstorms are expected to affect the approach or departure; and

e)  when the crosswind component, including gusts, exceeds 28 km/h (15 kt), or the tailwind component, including gusts, exceeds 9 km/h (5 kt)”.

2.7.4 Ground management

Hush houses and engine run up management

This enhances carefully chosen locations for engine run-ups and testing in perspective to build-up areas’ around the aerodrome. Also the time of day, the level of thrust and the direction in which the aircraft is pointed will contribute to the level of noise affected.

APU management

Minimizing APU use can save a considerable amount of fuel.

Taxi and queue management

Start-up planning and management will increase efficiency and reduce traffic jam on taxiways and therefore improve fuel-efficiency and subsequently reduce emissions and noise.

Towing

Towing instead of taxiing for repositioning or maintenance reasons and to remote de- icing spots will reduce noise and emissions.

Taxi power control

Single engine taxi will economize operations and will increase fuel efficiency.

2.8 Visual intrusion

2.8.1 The measurement of visual intrusion or tranquillity is not well developed. There is no universally accepted metric by which tranquillity can be measured, although several interesting ideas have been suggested. There is very little published material on the subject of visual intrusion with respect to aircraft. There is some literature on the subject of visual intrusion related to wind farms but there is not an obvious way of applying this method to aircraft. It should also be noted that Areas of Outstanding Natural Beauty (AONB) and national parks are afforded certain statutory protection. However, this does not extend to precluding overflight by aircraft. However, related to this subject, an environmental action group in the UK has started a legal procedure to stop aircraft overflying a national park.

3.1  Air transport is essential, an integral and vital part of modern society. 80% of aviation emissions are related to flights over 1,500 km for which there is no alternative mode of transport. According to the IPCC, aviation is responsible for around 5% of the total of all anthropogenic emissions.

3.2  In the short-term, improved ATM systems have the greatest potential of the currently available measures for delivering significant environmental benefits by reducing fuel burn and emissions through optimised flight paths.

3.3  Aircraft fuel efficiency has improved since the beginning of aviation. Airlines and manufacturers of aircraft will continue on improving fuel efficiency in order to minimize the effects on the environment and reduce costs. The increasing cost of fuel clearly makes the need for efficiency indisputable. In this process the stakeholders are already putting in the maximum effort to gain improvement.

It is recommended that;

4.1. This paper is accepted as information material.

ICAO Assembly Resolution 35 5.

ICAO Annex 3 Meteorological Service of International Air Navigation.

ICAO Annex 6 Operation of Aircraft.

ICAO Annex 16 Environmental Protection.

ICAO Doc 4444 Air Traffic Management.

ICAO Doc 8168 Aircraft Operations, Volumes I – V.

ICAO Doc 9836, CAEP/6 Report of the Committee on Aviation Environmental Protection.

ICAO Doc 9884 Guidance on Aircraft Emission Charges Related to Local Air Quality.

ICAO Doc 9885 Draft Guidance on the use of Emissions Trading for Aviation.

ICAO Doc 9886, CAEP/7 Report of the Committee on Aviation Environmental Protection.

ICAO Review of the Report of the OPSP/6 Meeting.

CAA PAPER 2004/08 Delivering Safety in the Context of Environmental Restrictions.

CAA CAP 725 CAA Guidance on the Application of the Airspace Change Process.

Commission of the European Communities, Reducing the Climate Change Impact of Aviation.

IPCC assessment Report On Climate Change.

IPCC Special Report on Aviation and the Global Atmosphere.

“The Great Global Warming Swindle” documentary produced by the BBC.

Optimization of yearly airport capacity within noise limits at Schiphol Airport.

IFATCA WP91 Cancun 2002.

Aviation and the Environment – Killing Myths and Setting the Agenda, Anthony Concil, IATA.

Report of The High Level Group for the future European Aviation Regulatory Framework.

Giving wings to emission trading, Inclusion of aviation under the European emission trading system (ETS).

Clearing the Air, The Myth and Reality of Aviation and Climate Change, T&E 06/2.

Aviation and global climate change, Friends of the Earth.

Air travel taxation is no solution to climate change, by David Browne.

Aviation and climate change, some food for thought, European Federation for Transport & Environment.

EU Aviation Policy and Climate Change, DG Energy & Transport European Commission.

https://www.icao.int/icao/en/env/ReviewNADRD.pdf