Description of the Flight Path

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Reference conditions for aeroplane aerodynamic and engine data:

 Runway Elevation: Mean sea level

 Air temperature: 15 °C

 Takeoff gross weight: As defined as a function of stage length in the ANP (Aircraft Noise and performance Database)database (http://aircraftnoisemodel.org)

 Landing gross weight: 90 percent of maximum landing gross weight

 Engines supplying thrust: All

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specified power and flap settings. The corresponding vertical coordinates are often referred to as profile points.

For noise modeling, flight path information is generated either by synthesis from a set of procedural steps (i.e. those followed by the pilot) or by analysis of radar data - physical measurements of actual flight paths flown. Whatever method is used, both horizontal and vertical shapes of the flight path are reduced to segmented forms. Its horizontal shape (i.e. its 2-dimensional projection on the ground) is the ground track defined by the inbound or outbound routing. Its vertical shape, given by the profile points, and the associated flight parameters speed, bank angle and power setting, together define the flight profile which depends on the flight procedure that is normally prescribed by the aircraft manufacturer and/or the operator. The flight path is constructed by merging the 2-D flight profile with the 2-D ground track to form a sequence of 3-D flight path segments.

3.3.1.4.2 Source of Flight Path Data

3.3.1.4.2.1 Radar Data. Although aircraft flight data recorders can yield very high quality data, this is difficult to obtain for noise modeling purposes and radar data must be regarded as the most readily accessible source of information on actual flight paths flown at airports. As it is usually available from airport noise and flight path monitoring systems, it is now used increasingly for noise modeling purposes.

However the analysis of radar data is a complex task for which methods are still under development.

3.3.1.4.2.2 Procedural Steps. In many cases is not possible to model flight paths on the basis of radar data - because the necessary resources are not available or because the scenario is a future one for which there are no relevant radar data.

In the absence of radar data, or when its use is inappropriate, it is necessary to estimate the flight paths on the basis of operational guidance material, for example instructions given to flight crews and aircraft operating manuals - referred to here as procedural steps. Advice on interpreting this material should be sought from air

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traffic control authorities and the aircraft operators where necessary (ECAC.CEAC Doc29, 1997).

In Table 3.1 there is a summary of the reviewed standards with their main contents.

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Table 3.1 Summary of international aviation standards

1. Determination of the Required Land Area 2. Factors Affecting Airport Location 3. Office Study of Possible Sites - Site Inspection

- Environmental Study - Review of Potential Sites

- Preparation of Outline Plans and Estimates of Costs and Revenues

- Final Evaluation and Selection - Report and Recommendations

1. Airport and its Environs 2.Need for Environmental Control 3.Need for Land use Planning

4.Environmental Impacts Associated with Aviation Activities - Aircraft Noise

- Air Quality

- Water and Soil Pollution - Waste

- Environmental Problems Arising from Aircraft Accident/Incident 5. Environmental Consequences and Control Measures - Noise Abatement

- Air Pollution Control - Water Pollution Control - Waste Management - Energy Management - Environmental Emergencies

- Environmental Impact Assessment of Airport Development - Environmental Management

6. Land-Use Planning

- Assessing Noise for Land-Use Planning - Noise Zones and Associated Maximum Noise - Risk of Aircraft Accidents around Airports - Land Uses within Noise Zones and High Risk Zones 7. Land-Use Control Systems

- Planning Instruments - Mitigating Instruments - Financial Instruments

Aircraft Noise Modeling 1. Concept of Segmentation 2. Flight Paths: Tracks and Profiles 3. Airport and Aircraft Operations - General Airport Data

- Runway Data - Ground Track Data - Air Traffic Data - Topographical Data - Reference Conditions

4. Description of the Flight Path

- Relationships between Flight Path and Flight Configuration - Source of Flight Path Data (Radar Data,Procedural Steps)

ICAO ANNEX 14

ECAC.CAEC Doc.29 Aerodrome Design and Operations– Airport Planning

Land Use and Environmental Control

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CHAPTER FOUR

ENVIRONMENTAL MANAGEMENT AT CONSTRUCTION AND OPERATION PHASES FOR AN AIRPORT

This chapter is a review of the environmental management at an airport for construction and operation phases. The environmental issues in this part are mainly about land use, soil erosion, impacts on surface and subsurface water drainage, and the impact on flora and fauna. Environmental problems do not exist when a new airport is being developed. These problems also exist when airport operations are continuing or when an airport is being expanded. Each airport may have different problems related to the area at which the airport exists.

Soil erosion problems can generally be prevented by replanting; however, in arid areas it can be necessary to take artificial erosion protection measures, such as facing of escarpments, paving of taxiway shoulders and lining of drains.

During construction phases of airports special consideration should be given to possible water pollution. Construction activities likely to cause stream pollution include clearing, grubbing and pest control. For instance, the clearing of vegetation generally results in greater soil erosion into streams. Pest control, particularly the use of sprays, can introduce long-life toxic chemicals into the water. Fuel spillages from equipment and chemicals used in building and pavement construction work can disrupt the hydrological balance of waterways in the area. Changes to the natural drainage patterns of an area due to the construction of an airport can overload certain streams and give rise to flooding. Diversion of flow may cause streams to dry up.

The sitting of some airports may interfere with the shorelines of rivers, lakes and the sea. In planning such airports, careful consideration should be given to possible environmental problems associated with water currents, silt deposits, impacts on marine or fresh water life and marine or stream erosion.

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The utilization of land for airport purposes can also cause disturbances to flora and fauna. Airport development work frequently entails clearing and cutting back of trees and other vegetation, changes to the topography of the area, and interference with watershed patterns. Thus airports may destroy the natural habitat and feeding grounds of wildlife and may deplete certain flora that is vital to the ecological balance of the area.

There are also potential impacts on human beings. For example, airport construction may destroy sources of food or firewood, or may cause agricultural land loss that is a major concern in certain areas of the world.

An important consideration related to airport operational safety is the prevalence and habits of birds in the area and the associated risk of aircraft bird strikes. Bird hazards at proposed new airports can be minimized by careful selection of the site to avoid established bird migration routes and areas naturally attractive to birds and by using the land surrounding the airport for purposes which will not attract concentrations of birds to the area. At existing airports, the bird problem may be controlled by scaring techniques and by making the airport and its environment unattractive to birds. The subject of bird strike reduction is also covered in detail in the Airport Services Manual Part 3, Bird Control and Reduction (ICAO Doc. 9137, 1999).

As far as these environmental problems are concerned, airport construction is not significantly different from any large construction site. In many countries, the issue is governed by general legislation on planning and development of construction sites.