Dissecting the Air Traffic Chain:
Exploring Capacity and Efficiency from
Gate-to-Gate
By:
Marijke Weerkamp
m.weerkamp@student.rug.nl I s1330853
Supervisor University: Dr. Ir. H. van de Water Supervisor ADSE: Ir. J. Brandse
October 14th 2008
Faculty of Economics & Business Scorpius 90
Preface
The last six months I have been working on my Master Thesis, with this report as result. I wrote this thesis for the Master Technology Management at the Rijksuniversiteit Groningen, and performed my research at ADSE in Hoofddorp. During the project I had my ups and downs. Many people helped me at these moments, and I would like to thank all of them.
First my supervisor from the University: Hen van de Water. Without his help I would not even finished the project in the first place. Next to that he supported me during the entire research with the structure, methodology and execution of this thesis.
I would also like to thank my external supervisor Jeroen Brandse, from ADSE. He helped me to get the problem clear, and to get in touch with the right people who could help me solving the problem. Jeroen also introduced me in the company and made sure I had a great time over there. All colleagues who helped me with my research; thanks for your contribution. And all the others I would like to thank for their support and social talks during lunch and coffee breaks.
My brother Wouter has been a great support for me. In the starting phase he helped me to structure the research, and in the end he checked all the English grammar mistakes. I would like to thank my parents, who always believed in me and offered me an ear to lend, and made sure I would finish the project. All my dearest friends who helped me with some distraction when I needed it, Hilde thanks for all your emails! My co-assessor Mr. Frans Bakker. And all my co-students with whom I spend my study time in Groningen, and most of the time enjoyed working with.
Abstract
Air traffic is continuously growing, the forecast is that the number of flights will double during the next twenty years. This growth in demand is constrained by several factors. One of the major factors is the capacity and efficiency of the gate-to-gate chain. The gate-to-gate chain describes the whole system of air traffic, starting from the point where a plane is parked at the departure gate, and ending when the plane arrives at the destination gate. Due to lack of capacity and inefficient processes in the gate-to-gate chain, the growth in demand cannot be met and this leads to congestion.
This research looks at the whole gate-to-gate chain and in which part the real problem regarding congestion lies. This leads to the following research question: “Where in the gate-to-gate chain can improvements be made, to improve the chain to a satisficing level?”
To give an answer to this question, a research is performed following the DDC methodology. DDC stands for Diagnosis, Design and Change. In the Diagnosis phase the problem is made clear, and in the Design phase a solution is constructed. The Change part is left out of this research. Due to the complexity of the problem, both soft and hard methods are used during the research.
First the gate-to-gate chain needs to be set out. This chain can be divided into a vertical and a horizontal chain. The horizontal chain describes the different flight phases and their characteristics. The stakeholders and the different processes related to the flight phases are described in the vertical chain. Next the horizontal chain can be researched by looking at the capacity of the different flight phases occurring in the gate-to-gate chain. This is done by constructing a capacity-model. In the capacity-model the maximum available capacities of each flight phase are calculated and compared. The runways are the bottleneck, but the maximum available capacity of the TMA and en-route phase cannot be calculated.
To still come to a clear view of the problem, another method is introduced. The Delphi method leads to a more complete view of the gate-to-gate chain and its problems. The Delphi method stands for individual, anonymous interviews with experts on the topic. From each stakeholder one or two persons are defined as experts. In the first round the experts receive a questionnaire. The results of these questionnaires are compared and the results are send back to the experts as feedback. In the second round the experts can respond to the feedback and answer new questions. Finally this leads to consensus among the experts about the topic. The experts agreed on the fact that the real cause of congestion in the gate-to-gate chain can be found in the air part of the chain., instead of the airport side. When demand grows, the real problem will occur in the TMA and en-route phase. Due to inefficient processes in these phases, congestion will arise.
the brainstorm session two groups of employees draw Rich Pictures, in which all the related processes are described. By discussing the Rich Pictures a ranking of processes arises. Four processes are identified as being most important, i.e. most contributing to the congestion in the air. These are: ATC processes, organization process of the airspace routes, safety issues, and information services. To more ground this ranking of processes, a new method is introduced: AHP ranking. Each participant needs to rank the different processes using an AHP matrix. This matrix compares the different processes pair wise, and a final ranking will appear. All individual rankings are combined into one final ranking, and after this a joint ranking is made. The individual rankings are not exactly the same as the ranking from the Rich Pictures, due to dependencies among the processes. The joint ranking is equal to that from the Rich Pictures. So this ranking is used by creating a solution for the problem.
The following recommendations are done:
For the ATC processes the high workload for the controllers need to be solved. This workload is caused by the inefficiency of the performed tasks. By automating systems, a lot of work can be done more efficient.
The structured air space and the indirect flight routes can be solved by continuing with the implementation of SESAR and FAB’s. This will in the end lead to one single European sky. The collaboration between different national ATC’s and civil and military air traffic needs to be optimized.
Safety procedures and margins cause inefficiency in the system. Due to inaccuracy safety procedures and margins are necessary, by eliminating this inaccuracy the margins can be decreased and this will lead to a more efficient performance of specific processes. This can be done by automating systems.
Table of contents
PREFACE ... 2 ABSTRACT ... 3 TABLE OF CONTENTS... 5 LIST OF ABBREVIATIONS ... 7 1 INTRODUCTION... 8 1.1 AIR TRAFFIC... 8 2 PROBLEM STATEMENT ... 10 2.1 MOTIVATION... 10 2.2 RESEARCH GOAL... 13 2.3 RESEARCH QUESTIONS... 13 2.4 RESTRICTIONS... 15 3 RESEARCH REVIEW ... 17 4 METHODOLOGY... 21 5 DIAGNOSIS... 27 5.1 AIR TRAFFIC CHAIN... 275.2 GATE-TO-GATE CHAIN... 28
5.2.1 Horizontal chain – Flight phases... 29
5.2.2 Vertical chain – Stakeholders ... 29
5.2.3 Vertical chain – Processes... 33
5.3 CAPACITY... 36 5.3.1 Introduction ... 36 5.3.2 Capacity model ... 39 5.4 DELPHI INTERVIEWS... 43 5.5 OUTCOMES... 46 6 DESIGN... 49 6.1 BRAINSTORM SESSION... 49 6.2 OUTCOMES... 50 6.3 AHP RANKING... 52
7 CONCLUSION AND DISCUSSION ... 55
7.1 CONCLUSION... 55
7.2 RECOMMENDATIONS... 57
7.4 FURTHER RESEARCH... 59
REFERENCES ... 61
APPENDIX 1 CHAIN... 64
A1.1 AIR TRAFFIC CHAIN... 64
A1.2 GATE-TO-GATE CHAIN... 66
A1.3 ATC PROCESSES... 67
APPENDIX 2 BRAINSTORM SESSION 1... 68
A2.1 FACTORS CAPACITY & EFFICIENCY FLIGHT PHASES... 68
A2.2 CALCULATIONS USED & AVAILABLE CAPACITY... 69
APPENDIX 3 DELPHI METHOD... 70
A3.1 DELPHI INTERVIEWS ROUND 1 ... 70
A3.2 DELPHI INTERVIEWS ROUND 2 ... 71
APPENDIX 4 BRAINSTORM SESSION 2... 74
A4.1 RICH PICTURES... 74
APPENDIX 5 AHP ... 76
A5.1 INDIVIDUAL RANKINGS... 76
A5.2 COMBINED RANKING... 77
A5.3 JOINT RANKING... 77
List of abbreviations
AAS Amsterdam Airport Schiphol
ACC Area Control Centre
ADSE Aircraft Development and Systems Engineering ANSP Air Navigation Service Provider
APP Approach Centre/Control
ATC Air Traffic Control
ATM Air Traffic Management
CFMU Central Flow Management Unit
CTA Control Area
CTR Control zone
FAB Functional Airspace Block
LAS Lower Air Space
RVSM Reduced Vertical Separation Minimum
SES Single European Sky
SESAR Single European Sky ATM Research
TAT Turnaround Time
TMA Terminal Manoeuvring Area
1
Introduction
This report describes the research project performed at ADSE. ADSE is a consulting and engineering company specialized in Aerospace, Defence, Infrastructure and Rail transport. The company was founded in 1996 by Henk de Groot, after the bankruptcy of Fokker. There are about 85 employees working at ADSE, especially with a background in Aerospace, Electrical or Mechanical Engineering.
The research project will focus on the air traffic chain. In the next paragraph a short introduction to the air traffic industry will be given.
1.1 Air traffic
The first powered flight took place in 1903 by the Wright Brothers. In addition to this breakthrough several airships and small airplanes were developed. But only in the 1920s and 1930s real progress was made. Planes that could exclusively carry passengers were introduced, and many cities and countries built airports. World War II brought several innovations to aviation. After this war the general aviation business grew fast. There were many pilots and aircrafts from the military available. Manufacturers produced new light aircrafts for the middle class market. In the 1950s a new civil plane was introduced, the Boeing 707, the first widely used passenger jet. In the following years planes became more efficient and quiet. Instrumentation and control were improved by new radar systems, satellite connections and GPS. Today, over 10 million flights a year are performed in Europe only1.
Aviation can be divided into civil aviation and military aviation. Civil aviation includes all non-military flights, both general aviation and scheduled air transport. General aviation is all the non-scheduled flights, like private jets, flight training, ballooning, parachuting, etc. Scheduled air transport includes all passenger and cargo flights operating on regularly-scheduled routes. All scheduled air transport is commercial, i.e. flying for hire. General aviation can either be commercial or private; pilots flying for their own goals.
The passenger air fleet exists of different airplanes, ranking from small charters to the large air crafts. These planes have different velocities, safety regulations and required handling operations.
To regulate all these airplanes in the air and on the ground Air Traffic Control (ATC) was introduced. ATC helps aircrafts to maintain separation and by doing so keep the airspace and the airports safe. The airspace is divided into several ATC zones. The flight height indicates in which zone you fly, see
1
Figure 1 left. The zone that stretches out from airport till an established upper limit is called Control Zone (CTR). CTR controls the planes at the ground and gives clearance for take-off and landing. The Terminal Control Area (TMA) is a controlled airspace set up at the contour of airports to protect climbing and descending traffic. The Approach Controllers (APP) operate in the TMA zone. APP will lead the plane through the traffic flows and control the beginning part of the climb. During descend APP will range the planes in a certain approach rank.
On top of the TMA the Control Area (CTA) is situated. This airspace is divided into a lower and upper level, the LAS and the UAS. En route traffic controllers operate in centers called Area Control Centers (ACC). The responsibility of the ACC is to guide planes to their flight altitude and protect the safety distance between planes.
Each country has its own airspace block (see Figure 1 right). National control centres or Air Navigation Service Providers (ANSPs) operate in these blocks. ANSPs are organizations that separate aircrafts both on the ground and in flight in a dedicated block of airspace on behalf of a state or a number of states. All these blocks have specific routes, which the airplanes follow. The planes have limited freedom to fly where they want in a block, but they fly from one recognised point (a waypoint) to another.
Figure 1: Airspace divided into control zones and flight blocks2
2
Source: www.vatpac.org/nzair/nzair.htm &
2
Problem statement
2.1
Motivation
Situation
Air traffic in Europe has tripled between 1980 and 2000 and is continuously growing. Between 1992 and 2005 the number of intra-EU routes has increased by 150%3. The long-term forecasts conducted by Eurocontrol4, the European organization for the safety of air navigation, show a more than doubled number of flight movements in the European sky, see Figure 2. The graph is based on four different growth scenarios. These scenarios range from a strong economic growth in a globalised world, to a world with increasing tensions between regions and weaker economies.
Figure 2: Demand air traffic (Eurocontrol, 2006)
The growth in demand in the next years will be constrained by several factors. An increase in flight movements will bring more pollution. Air and noise pollution is restricted by regulations5, so an
3
Communication from the commission to the council, the European Parliament, the European Economic and Social Committee and the Committee of the Regions: An action plan for airport capacity, efficiency and safety in Europe. Website:
http://ec.europa.eu/transport/air_portal/airports/doc/2007_capacity_en.pdf
4
Eurocontrol Long-term Forecasts, Flight movements 2006-2025. Website:
unlimited growth without any adjustments to the emission of planes is not possible. Next to this there is the restriction of safety. Safety regulation in air traffic is very strict. More flights will be no problem, on condition that it will not harm the safety of passengers, crew and environment.
Another major constraint is the capacity of airports and airspace. A doubling of the number of flight movements requires a large expansion of the capacity of airports and airspace. Capacity is defined as the amount of flight movements an airport or part of airspace can handle per time period. This can be in terms of operations, infrastructure, space, or even money. In this research there will be looked at physical capacity of the airport and airspace. The physical factors which lead to a certain amount of flight movements that can occur at an airport or in the air will be taken into account. For example the arrival-capacity of an airport is based on the number of runways and taxiways available, the available gates, the velocity of planes and their separation distance. Looking at this capacity the efficiency of the processes plays a major role. Inefficient use of the processes can also become a constraint for the capacity and therefore for the possibility of demand to grow.
Under current conditions airports and airspace are not able to handle future demand. According to several studies6 the capacity of the air traffic chain is not sufficient for the future amount of flight movements in Europe. This can be in terms of the physical capacity like available runways and airspace, or the use of this available capacity. How efficient capacity is managed is an important factor in this issue.
Complication
With a growing demand and a stagnating capacity, congestion is likely to occur. Congestion is a blockage of the operational space, and can be best compared with (air) traffic jams. When the demand of road users is larger then the amount of roads, it will lead to traffic jams: a congestion of the roads. In the air and on the ground at airports, the same principle is rising. When there are more airplanes that want to transport people, than there is allocated airspace in which they can fly and airports on which they can land, congestion will occur.
Congestions will lead to an influent throughput of airplanes. It can occur that planes have to wait in the air before they can land at a certain airport. Or they have to fly through a different sector, because of the occupation degree of that sector. There might be too little air traffic controllers to handle all the planes that would like to fly through that sector or due to safety regulations, the sector is full. Another problem that can occur is long waiting times for planes at the ground. This can happen when there are not enough runways available to depart or not enough gates to unload the plane.
Congestion is not only an effect of lack of (used) capacity. It can also turn into a cause of this problem. Due to congestion and waiting times in the air, planes will expel more pollution than by flying directly to
6
their destination. The regulation around emission is a constraint to the capacity of airspace and airports. Regulations allow a maximum of noise and air pollution from airplanes. This limits the maximum number of flights movements in a part of the airspace or at an airport. So when planes produce more emission due to congestion, they will be restricted by these regulations. Fewer airplanes can fly at the same time in a specific sector, or depart/arrive at an airport; this will harm the capacity of that sector or airport. Not the physical capacity will be reduced, but the capacity due to regulations. This will lead to lack of capacity and eventually more congestion.
All these problems have an inefficient flow of planes as result. Such an inefficient flow will lead to delays of airplanes. Delays are the result of congestions, but also of unexpected events. These unexpected events, like bad weather and interruptions, will not be taken into account in this research. Although it has a major impact on congestions and therefore on delays, it will take too much time to research this.
Research
To limit the congestion, demand should be stagnated, or the constraints (limited capacity/regulations) that limit the growth of air traffic flow should be subsided to a certain level. Total elimination of the constraints will lead to an infinite growth of air traffic, which again will lead to more congestion. A balance should be found.
The focus in this research is on the transportation of people through the air. This transport has to be done efficiently, without any interruptions as mentioned above. Constraints, congestion, and delays all contribute to the efficiency of the transport of people. Because delays and congestion derive from constraints, this research will be aimed at these constraints. By researching this, a start is made for improving the efficiency of the transportation of people through the air.
Air traffic can be seen as a chain. It is a process which starts when a passenger decides to book a flight, and ends when the passenger walks out of the destination airport. Between these points many operations occur. Because these operations are sequenced and linked to each other, the whole process can be seen as a chain. However, due to all integrated information and communication processes, it is a chain with network characteristics. The flight phases are sequenced in a chain, but several processes are networked in the chain. This will be further explained in Chapter 5.
The gate-to-gate chain is investigated by looking at the constraints of the links, like environmental and safety regulations although the focus is on capacity. Regulations influence the capacity of airports and airspace in some way. Planning also influences capacity. In theory a good planning can positively contribute to the capacity case. Distributing the flight movements over the day will prevent certain peak times with under capacity, or quiet periods with over capacity. All these processes will be discussed in Chapter 5.
Economical factors are not taken into account. Economical factors can be a major constraint, both for capacity as for demand. Because of the limited time for this research, this is left out.
The future problems in the air traffic, like lack of capacity and congestion, will probably occur from one or more problems in the air traffic chain. It is necessary to identify these points. Identifying the cause of the problems is the first step in improving the air traffic chain.
In this research the goal is to identify this cause and to improve the chain. The improving phase is not conducted in this research, but can be the starting point for a new research.
2.2
Research goal
Regarding the motivation above, the research goal is as follows:
Transport people efficiently in the gate-to-gate chain
The aim is on transporting people in the air efficiently. Efficiently refers to doing the work right. It can be seen as the quotient of the expected offer you have to make to achieve something, and the real offer you made7. In this case it means transporting people from one gate to the other gate, doing this with a minimum offers made. These offers depend on interruptions and delays.
2.3
Research questions
In order to achieve the goal of this research we need to define a research question. This research is focused on the gate-to-gate chain and making this chain more efficient. It is not possible to optimize the chain; this is beyond the scope of this research. So a satisficing result is pursued. Satisficing means to meet criteria for adequacy, rather than to identify an optimal solution: Satisficing is looking for solutions that are an improvement to a system. These solutions are not intrinsically the “best ones”.8 One of them probably is, but it is not the purpose of pursuing a satisficing result to identify that
7
Analyse van organisatieproblemen, In ‘t veld, J., 1996
8
best solution. In the research the satisficing theory is applied because it is not possible to test all possible solutions, and then select the best one. The available time is not sufficient, and testing all solutions is not considered feasible.
Making the gate-to-gate chain more efficient probably means that some improvements to the chain need to be made. However, as stated in the motivation section (2.1) the implementation of these improvements is not part of this research. We propose several recommendations of places to implement any improvements.
The previous leads to the following research question.
Where in the gate-to-gate chain can improvements be made, to improve the chain to a satisficing level?
The research question is answered in this report by answering several sub questions. It starts with investigating the gate-to-gate chain at a high aggregated level; the flight phases. By defining the links of this chain and their characteristics, it is possible to investigate the physical capacity of the different links. This probably leads to the identification of a most restrictive link in the chain. The following sub questions need to be answered for this phase:
1 Looking at the gate-to-gate chain at a high level (flight phases), what are the different links? 2 What are the characteristics of, and relations between, these links?
3 How can we define the physical capacity and the efficiency of the links in the gate-to-gate chain?
4 Looking at these capacities and efficiencies; what is the most restrictive link?
In this phase of the research a most restrictive link is identified from the sub questions above. This link is defined as the bottleneck of the system. A bottleneck is an element which has a substantially smaller capacity than that of preceding or succeeding elements. When demand stays below the capacity of the bottleneck, there is no problem. However when demand exceeds that capacity, delays will occur9. Goldratt (1999) developed the weakest link theory10. Every chain consists of a weakest link; the most restrictive link. This link must be identified and is the bottleneck. A buffer should be placed in front of the bottleneck, so the bottleneck will always operate at its full capacity. Improving a chain is only possible when the weakest link is improved. It is initially not of any use to strengthen other links, because the strength of the chain is determined by the strength of the weakest link. However, the linkages between the links are as important as the links itself. Improving the capacity of one link can have a negative influence on the capacity of another link. So when looking at one link, the
9
Congestion Theory and Transport Investment, Vickrey, 1969
10
relations with the other links should be examined too, considering these can influence each others capacity.
After defining the most restrictive link, recommendations can be made to improve the gate-to-gate chain to a satisficing level. These recommendations should concern the weakest link, because by improving the weakest link, the entire chain will be improved. This will be done by answering the following sub question:
5 What improvements can be made to relieve the capacity problem?
When it is not possible to make satisficing improvements on this level of detail, the bottleneck-subsystem is investigated in more detail. A new model is designed to map all the elements and the relationships. By investigating these elements and relationships, it might be possible to identify a new restrictive factor. This factor is seen as the problem of the capacity issue. The following sub questions lead to this:
6 What is an appropriate level of detail? 7 How can this subsystem be modeled?
8 How do the elements of the modeled subsystem interact with each other?
9 How can these elements and their relationships be measured, with regard to the capacity problem?
10 Which relationships and/or elements cause the greatest problems in the capacity issue? 11 What improvements can be made to relieve the problem?
By the previous sub questions the problem is identified at a more detailed level. This problem can be seen as the most restrictive factor in the detailed gate-to-gate chain. When this is achieved, recommendations can be made to improve the gate-to-gate chain to a satisficing level. It is possible that sub questions 6 till 11 will not be performed in this research, because the recommendations made by sub question 5 are sufficient for this research.
2.4
Restrictions
The research is done by using data of Amsterdam Airport Schiphol. The focus is on AAS and the European airspace.
Economical factors are left out of this research.
Assumptions are made when the correct data is not available. These assumptions are based on estimations from experts in the field.
This research is done in a time period of 5 months.
Stakeholders are limited to the most relevant national stakeholders, so not all European and international stakeholders are part of this research.
3
Research review
This chapter briefly describes the conducted literature research. This research is started by searching for related articles and studies. First a distinction is made between scientific articles and social studies. Scientific articles are scientific grounded; they are written by scholars and published in scientific journals. By social studies we mean studies conducted by research institutes, other than universities, for example the National Aerospace Laboratory. Articles and studies are searched online using google.scholar.com.
Scientific articles
The table below represents the results of the search. These are recent articles from 2003:
Keywords Number of (recent) articles
“Air traffic” capacity 8.200
Air traffic flow efficiency 20.600
Gate-to-gate capacity 244
Table 1: Search results
The time for this research is too limited to review all articles, so a selection is made. This is done based on the number of times they have been cited. The most cited articles are evaluated on their abstract, and subdivided in prescriptive or descriptive. Descriptive articles describe the situation and prescriptive articles come with a solution or recommendation; a prescription. Another difference is whether they are based on theory or on experiments (empirical). Finally, we have 9 relevant articles which are situated in the following model. The blue sections represents the most relevant articles for this research, and these are described below.
Empirical Theoretical Prescriptive - Erzberger - Miller - Song - Ferchaud - Welch - Erzberger - Miller - Miltiadis - Welch Descriptive - Song - Zelinski - Majumdar - Menon
In the article “Transforming the NAS”11 by Erzberger, the en route phase is described and a new system that controls air traffic is introduced. This study is based on the American airspace, and is mainly focused on safety of planes and ATC. It states that en-route capacity is limited by the controller workload. Therefore a new system is designed that reduces the workload of controllers using computers and automation. The focus in the article “Communication and the future of air traffic management”12 (Miller) is also on the United States’ National Airspace. The NAS has to grow to handle the passenger demands of the future. It is constrained by operational and technical issues in the terminal area. A new project is set up to increase the capacity in this area. This project is aimed at automation and improving terminal operations and infrastructure.
In the article from Miltiadis: “A decision support system for airport strategic planning”13, the focus is on the airport side of the gate-to-gate chain. Models are constructed to estimate the capacity of an airport, and a decision support system is developed for strategic airport planning. The system is dependent of the characteristics of airport capacity and demand, and on airports operations. The article “Predicting sector capacity for TFM decision support” 14 by Song is also aimed at a decision support system. It looks at the en-route capacity and the prediction of it. A model is constructed to predict capacity under certain circumstances.
“Slot allocation under uncertainty” 15 (Ferchaud) outlines the capacity of the European airspace. Capacity must increase to handle demand, but safety can not be harmed. Since the airspace is a complex system, all parties should be involved when increasing the capacity. The aim of the study is to increase the used capacity by improving managing of the available capacity. So the real capacity will not be increased, but it will be used more efficient and therefore more flights can take place. The en route capacity is also the main topic in the article from Welch: “Macroscopic workload model for estimating en route sector capacity”16. This article looks at the workload of controllers, and the maximum of air traffic flow they can handle, which is called design capacity. Under specific circumstances the capacity decreases, for example due to bad weather, this is called the dynamic capacity. To handle unforeseen events it is necessary to have a clear view of the capacity of the en route sector. The authors develop a model to predict the required capacity of controllers.
11
Transforming the NAS: The next generation Air Traffic Control system, Heinz Erzberger, October 2004, NASA STI program office
12
Communication and the future of air traffic management, Miller, M.E., Dougherty, S.P., 2004
13
A decision support system for airport strategic planning, Stamatopoulos, M.A., Zografos, K.G., Odoni, A.R., 2004
14
Predicting sector capacity for TFM decision support, Song, L., Wanke, G., Greenbaum, D., 6th AIAA Aviation Technology, Integration and Operations Conference (ATIO), 2006
15
Slot allocation under uncertainty, Ferchaud, F., 3rd International Conference on Research, Innovation and Vision for the Future, 2005
16
Social studies
We review relevant social studies in a similar fashion. Via google.scholar.com and google.com conducted studies are found. By reading the abstract, a few studies are found to be really useful. The studies are from research institutes operating in the air traffic business and are discussed below.
The National Aerospace Laboratory (NLR) conducted several studies in the topic of capacity and efficiency in air traffic. Three relevant studies are "Flow Management on the ATM Network in Europe”17, “Refined Flow Management: An operational concept for Gate-to-Gate 4D flight planning”18 and “Airport Modeling: Capacity Analysis of Schiphol Airport in 2015”19. The first two studies focus at the ATM system and its performance.
In the third study the capacity of Schiphol is measured to see if it meets demand. This is done by using a simulation model. The conclusion of the study is that using more runways simultaneously and segmentation of arrivals by wake turbulence category leads to an increasing capacity.
The paper “Paradigm SHIFT: A contract-based ATM organization in line with SESAR recommendations”20 describes the key SESAR recommendations. SESAR is a project of the European Commission to redesign the ATM system with support of all stakeholders and innovative technologies. The SESAR consortium21 studies of Eurocontrol describe the whole project from step to step. This project is aimed at consensus between stakeholders. It is focused on ATM, managing of the air space. It does not look at the different steps in the gate-to-gate chain.
“An action plan for airport capacity, efficiency and safety in Europe”22 is a study of the European Union. In this study the focus is on the capacity of the European airspace. Safety, environment and economical factors play a major role. It states that the capacity of an airport is determined by the number of runways. Another measure is the communication and collaboration between stakeholders. Without accurate collaboration, the efficiency of the air traffic flow will not increase. This growth must be with respect to safety and environment. The European Commission prioritizes these factors, so the capacity growth is limited. An action plan has been set up to achieve regarding safety, efficiency, and capacity goals.
17
Flow Management on the ATM Network in Europe, Hugo de Jonge, Jos Beers and Ron Seljée, NLR, 2007
18
Refined Flow Management: An operational concept for Gate-to-Gate 4D flight planning, de Jonge, NLR, 2002
19
Airport Modeling: Capacity Analysis of Schiphol Airport in 2015, Polack, NLR,1997
20
Paradigm SHIFT: A contract-based ATM organization in line with SESAR recommendations, Guibert, S., Guichard, L., Dohy, D., Grau, J.Y., Eurocontrol, 2006
21
SESAR Consortium, Deliverable 1-6, 2000 – 2008, Eurocontrol.
22
In the study “Challenges to growth”23 of Eurocontrol the focus is on the interaction between traffic demand and airport capacity. The study describes four different growth scenarios of the flight demand. These scenarios are analyzed by looking at the environmental and airport constraints, which lead to the required capacity. The study is performed at 133 European airports, 80 % of the airports stated that they need to build more runways to handle demand. However this is difficult due to infrastructural, environmental and geographical reasons. When airports can not grow, there would be a market for up to 10 new major airports and 15 medium airports in Europe. The output is a number of recommendations about mitigating the constraints of capacity.
Comparison
For this research the scientific articles with a prescriptive nature are relevant, because the aim of this research is to give recommendations for improvements. This study can be seen as partially theoretical and partially empirical. Most articles found are prescriptive. However, none of them can be compared with this thesis. In this thesis the whole gate-to-gate chain is discussed, and the capacity of every link is determined. In the previous relevant articles, only one part of the gate-to-gate chain is investigated, like a physical flight phase, or a more social issue (e.g. workload and planning). They have already defined a bottleneck in the chain, and analyzed this link, without discussing the whole chain. Next to this the difference is in the nature of the articles. Many of them are based on economical factors. Privatizing, costs and local economy are objectives. In this thesis the aim is on the processes and capacity, and not on any economical factors. The scientific articles are also not focused on Schiphol or the European airspace, they are mainly performed in the United States, and the NAS. The methodologies of the previous articles are more technical, with models and statistical analysis. Simulations have been performed but due to the limited time period, this is not possible.
The social studies are more general and are not focused on a specific part of the gate-to-gate chain. They are softer, more aimed at the network of stakeholders than at the technical aspects of the different flight phases. These studies are more relevant for this thesis, because this thesis is also focused on the softer side of the problem, the technical details will not be investigated. However they are still different from this thesis. This thesis contains the whole process of identifying a weakest link in the gate-to-gate chain, to propose recommendations for improving this chain. None of the other studies covers this whole process. Therefore this research has been conducted, and this thesis has been written.
23
4
Methodology
To conduct this research a suited methodology is needed. With this methodology the sub questions are answered, it represents how data is collected or generated, and how it is analyzed by the use of specific methods.
In this research it is not only important to understand the gate-to-gate chain and all the processes related to it, but some interference in this chain also plays a role to reach the goal of this research. In the DDC method of de Leeuw24 all these steps are combined.
DDC stands for Diagnosis, Design and Change. These words represent the phases of the methodology. The first phase is to diagnose the problem, in a way that the problem becomes clear and the system is defined. The next phase covers the designing part of the research. The problem is clear and a solution for this problem is needed. In the design phase such a solution is constructed. The last phase contains the real changing part. By implementing the designed solution, the system shifts to an improved situation. The implementation phase will not be part of this research. A solution is constructed, but the real implementation can be done in a future study. Figure 3 represent the DDC method.
Figure 3; DDC model of de Leeuw Diagnosis
The diagnosis phase consists of the goal of the research and the system that is investigated. The goal is defined in Chapter 2: Transport people efficiently in the to-gate chain. The system is the gate-to-gate chain and all its elements and relations. The gate-gate-to-gate chain is the process of a plane that contains the parking and departure from one gate, up to the arriving at the gate of its destination. In this research the chain is subdivided in flight phases. It starts with the gate pushback, and ends with taxiing to the arrival gate. In between the following phases are defined: taxiing, departure, climbing,
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en-route, descending, and landing. The airport handlings will be viewed from Amsterdam Airport Schiphol. The airspace side is the European airspace.
The DDC method can be used when the definition of the real problem has not yet been made. Sub questions 1, 2, 3 and 4 can be used in the diagnosis phase to construct the real problem; the most restrictive link. Finding this link is done by looking at the whole chain and the characteristics of its links. The chain exists of various factors, processes and stakeholders. According to Jackson25 this can be defined as a complex system, because of the involved richly interconnected sets of parts and because the relationships between the parts can be more important than the nature of the parts themselves. From the literature26 it can be presumed that a hard and a soft approach are useful to solve these kinds of problems. In a hard approach the world is seen as made-up of systems that can be studied objectively and that have clearly identifiable purposes. The soft approach uses a more subjective view of the real world. Systems models that capture different perceptions of the problem are constructed27. We use both a hard and a soft approach for this research because of the complexity of the problem. By applying only a hard approach to this system, the different viewpoints of stakeholders and the variety of the processes are not researched in an appropriate way. The technical and static part is investigated, but the more social and dynamic part is forgotten. This side is just as important to solve this complex problem. In the same way it is not sufficient to only use a soft approach. Physical capacity, defined by real numbers, cannot be measured, and it is possible that this leads to the cause of the problem, and therefore to a solution. Both approaches are used in this research. The methods used for this hard and soft approach are briefly described below. When the methods are actually applied, they are described in detail (Chapters 5 and 6).
First the gate-to-gate chain is mapped. This is done by looking at the flight phases, their characteristics, and the related stakeholders. Sub questions 1 and 2 are answered afterwards. For sub question 3 the physical capacity of the links in the chain must be measured. This is done using theory and numbers of previous studies, but also using the knowledge of experts at ADSE gained in a brainstorm session. Capacity is measured at a high level, details and interruptions are left out of consideration. Physical capacity can be seen as the maximum number of flights that can pass through the flight phase, being safely and efficiently handled, in a given time period. In Chapter 5 a more detailed definition of capacity is given. The capacity model is a hard method.
Next to this hard approach, sub question 3 is answered by using a softer approach: interviews with experts. All experts have different views on the problem, the interviews must lead to a clear view of the problem, and how efficient the processes in the different links are performed. For these interviews the
25
Systems approaches to management, Jackson, 2000
26
Systems approaches to management, Jackson, 2000 & Systems thinking, systems practice, Checkland, 1981
27
Delphi method is used. Delphi is aimed at reaching consensus between different experts, in a complex problem. It is an individual interview method, so experts will not be influenced by opinions of others. Our problem can be seen as complex, due to the different stakeholders and all the associated processes. The stakeholders have different interests and the processes are really specific. By using the Delphi method independent knowledge of experts is extracted, and this can be helpful for this research. At the end of this chapter and in Chapter 5 this will be explained in more detail.
From the model and the interviews, one link must be identified as the most restrictive. This link can have the lowest available capacity, or is identified as the link with the most inefficient processes. This can be seen as the real problem of the system; the diagnosis. By identifying the most restrictive link sub question 4 is answered.
Design
After defining the real problem in the diagnosis phase, a solution can be constructed in the design phase. This is done by a brainstorm session with experts working at ADSE. This brainstorm session is described further along in this paragraph. The opinions of the experts will finally lead to clear recommendations that can be made to come to improvements for the gate-to-gate chain. Sub question 5 is now answered. However it is possible that during the brainstorm session it becomes clear that no real recommendations for improvements can be made on this level of detail. When this occurs, the gate-to-gate chain should be researched in more detail. A top-down method is used. We zoom in to a more detailed level using model reticulation28. The most restrictive link is modeled and the diagnosis phase starts again. This time the diagnosis is done on a different system level. But the goal is still be defining the real problem, so a solution can be developed in the design phase. The relationship between subsystems is also important. Changing something in one subsystem can influence the other subsystems, this might be in a positive way, or more negative. This should be considered when proposing and implementing the solutions.
Sub questions 6, 7, 8, 9, and 10 are answered in this diagnosis phase. Hereafter the real problem is defined at a more detailed level. The modeling of this link is done using the knowledge of experts from ADSE, which leads to a detailed model of the link, where the important elements and their relations are defined. Sub questions 7 and 8 can be answered now. For sub question 9 the elements and relations need to be measured. To measure this theory and knowledge from experts is used. These experts are interviewed using the Delphi method. After defining the capacity, the real problem on this detailed level can be identified. Sub question 10 is answered. In the design phase sub question 11 is answered using opinions of experts.
Change
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This phase is not part of this research. Recommendations are given in the design phase, but the actual implementations of these recommendations cannot be done, due to the scope and the design of this research.
Figure 4 represents the scheme of the research.
Figure 4: Methodology model Delphi method
In the diagnosis phase an interview method is used to obtain information about the efficiency of the gate-to-gate chain. These interviews are conducted using the Delphi method. The Delphi method is an individual independent interview method. Experts are interviewed without knowing it from each other. This way their answers are not influenced by opinions of others.
A Delphi procedure can be seen as a systematic way of collecting and processing opinions of experts29. These experts settle down in a Delphi panel. This method is especially aimed at objectivity. The goal can be to reach consensus between panel members, or to collect various arguments and alternatives for a problem. The interviews can be conducted by letter. The first round exists of an information session about the problem and the intent of the researcher. The panel members return their first ideas about the problem. Next the researcher processes these ideas and gives them back to the panel. The panel in their turn can adjust and extend their opinions. Two or three rounds should be enough for the researcher.
29
According to Pill30 the Delphi technique is a method of combining the knowledge and abilities of a diverse group of experts to the task of quantifying variables which are either intangible or shrouded in uncertainty. In this research the variables are uncertain and in some way intangible. Some of the required data to construct a well-founded capacity model is just not available, or very hard to obtain for the researcher. Obtaining this information through the knowledge of experts is then a useful method. The problem in this study can be identified as complex, due to the required data and all different stakeholders with their own viewpoints and relations. From literature and previous studies it is still not clear what the real problem is regarding to the efficiency of the gate-to-gate chain. All studies focus on different issues and work with different viewpoints. Therefore it is necessary to come to a shared viewpoint and a clear problem statement. Delphi method is a good tool for this.
Delphi will try to reach consensus between the experts so that the real problem and possible solutions can be defined. The results are not designed to represent a statistical sampling of a larger population, but only to reach a consensus group response to a difficult question31.
Delphi is also a technique used to obtain expert judgments about the likelihood of specific occurrences in the future32. The efficiency of the gate-to-gate chain is a long term problem, and due to growing demand in the future the problem will expand in the next years. Delphi is the right technique to deal with this kind of future problems.
In this research the experts can be identified as the stakeholders of the gate-to-gate chain. This means employees of the AAS, LVNL, Government, Eurocontrol and KLM are members of the Delphi panel. The stakeholders are described in Chapter 5.2.2. Some literature recommends 10-18 experts on a Delphi panel33, although another article stated that there are no universally agreed criteria for the selection of experts, and no guidance exists on the minimum or maximum number of experts on a panel; rather it appears to be related to common sense and practical logistics34.
Brainstorm session
Besides the Delphi method another way of obtaining information and reaching consensus is brainstorming. Brainstorming is a technique where a group of people discusses all kind of ideas about a specific topic. The goal of this technique is to come to one or more specific ideas about the topic, that can be used in further research. In this research two brainstorm sessions are held. The first one is
30
The Delphi method: Substance, Context, a critique and an annotated bibliography, Juri Pill, 1971
31
Responsible property investment criteria developed using the Delphi Method, G. Pivo, 2008
32
An Application of the Delphi Method of Forecasting to Nursing Education Planning in West Virginia, Doctoral Dissertation, Stead, F.L., 1975
33
The Delphi method as a research tool: an example, design considerations and applications, Okoli, C., Pawlowski, S.D., 2004
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aimed at obtaining information about the physical capacity of the different flight phases in the chain. This is done with ADSE employees. After the interviews the second brainstorm session is done. This session is performed in a SSM-like way. SSM stands for Soft System Methodology, and is a method that is useful to examine complex organizational issues, with social components. SSM is aimed at letting the members of the organization and/or the stakeholders of the problem participate in the process of examining. By the process the stakeholders should reach consensus and the problem can be defined and solutions can be implemented. In this research particularly the part of participating and reaching consensus is useful. Therefore we do not apply the whole SSM method, but it will be a brainstorm session with tools from the SSM method.
A group of 6 employees of ADSE participates in the brainstorm session. They are subdivided into two groups. Each group discusses their ideas about the problem situation, and draws a Rich Picture of the situation. These Rich Pictures represent how the groups look at the problem and all the related stakeholders, processes and relations. When the Rich Pictures differ a lot after comparing them, the groups draw a new picture. This process leads to a final collected picture. The described processes occurring in the problem situation will then be ranked by the employees on importance. The process that most contributes to the problem and is not too hard to change is defined as most important. During the brainstorm session everyone is asked to vote on the for him most inefficient processes. These rankings will lead to a final ranking of all the processes, and the 4 most important processes are further discussed to come to improvements.
AHP
To check the ranking made during the brainstorm session, the AHP method is used. This more “hard” method asks all participants to rank the same processes again. This time it is done individually. AHP stands for Analytic Hierarchy Process and is developed by Thomas L. Saaty in the late 1960’s. It is a methodology for structuring, measurement and synthesis. And is mostly used in choice problems in a multicriteria environment35. According to Saaty a common way to deal with complexity is hierarchically structuring the different factors. Because of the inability of humans to structure more than a certain number of factors, the AHP method is constructed. In this research many different processes are defined. To give some structure to these processes, they can be hierarchically ranked. Using the AHP method, this ranking is more objective and grounded then just rank them during a brainstorm session. The ranking of the processes is done by comparing alternatives in a pair wise manner. This is further explained in Chapter 6. A mathematical structure of matrices and eigenvectors is the basis of AHP, but this is not further explained in this research. For this research a self-constructed matrix is used and imported into an existed computer program.
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5
Diagnosis
In this chapter the diagnosis phase of the research is conducted. During this phase the problem situation is set regarding to the goal of the research and the investigated system. The goal of the research is efficiently transporting people through the air from point A to point B. The system is defined as the gate-to-gate process. This process can be seen as a chain, and is part of the whole air traffic chain. Within the gate-to-gate chain several stakeholders and processes are active. These processes and stakeholders do not all operate sequenced, but more in a network frame. Calling the gate-to-gate process a chain is not entirely correct. To keep it simple it is called a chain, which makes it easier to understand the sequence of the flight phases and to keep an overview of the whole process. After the description of the whole air traffic chain in the following paragraph, the gate-to-gate chain will be described in more detail and the different links and their capacity are defined.
5.1
Air traffic chain
P a s s e n g e r L u g g a g e P la n e D e c id e s t o b o o k a f lig h t / b u y s a t ic k e t T r a n s p o r t s t o t h e a i r p o r t C h e c k s i n E n t e r s r e s t r ic t e d a r e a G o e s t o t h e g a t e B o a r d s C h e c k e d i n I n s p e c t e d a n d s o r t e d T r a n s p o r t e d t o p la n e L o a d e d o n b o a r d P r e f lig h t o p e r a t io n s G a t e p u s h - b a c k T a x ie s t o r u n w a y T a k e o f f C lim b E n - r o u t e D e s c e n t L a n d T a x ie s t o g a t e A r r i v e s a t g a t e G e t s o u t o f p la n e W a lk s t h r o u g h t e r m in al C o l le c t s b a g g a g e P a s s e s s a f e t y a r e a W a l k s o u t o f a ir p o r t I s u n lo a d e d o f p la n e S o r t e d C o ll e c t e d b y p a s s e n g e r s P la c e d o n b a g g a g e c a r o u s e l D e p o s e s b a g g a g e C h e c k e d b y s e c u r it y
Figure 5: Air traffic chain
5.2
Gate-to-gate chain
process that can be allocated to the different flight phases. In this research we speak of a chain, to make it easier to describe the whole system. Appendix 1.2 represents the whole gate-to-gate chain.
5.2.1 Horizontal chain – Flight phases
Figure 6 represents the horizontal gate-to-gate chain. All different flight phases are reproduced. The horizontal chain starts with the plane parked at the gate. Baggage and passenger have been loaded in and the gate push-back starts. In this section the plane is pushed away from the gate and transferred to the taxi-way. After arriving at the taxi-way the plane starts its engines and depending on the weather it gets de-iced, or taxi straight to the take-off runway. From here the plane takes off. It climbs untill it reaches the flight-level. At this point the plane flies en-route. When the plane approaches its final destination, it starts the descent. The plane lands and taxis to its destination gate. All these phases are controlled by ATC, which is described in the following paragraphs.
Figure 6: Gate-to-gate chain (Eurocontrol, 2007)36
5.2.2 Vertical chain – Stakeholders
The vertical chain describes all the stakeholders related to the horizontal phases of the air traffic chain. The airspace is a complex socio-technical system. Next to the technological features required in this area, many stakeholders are involved with all different viewpoints and interests. This makes it a complex system. To make it simpler, the technical side is not discussed in this research.
ANSP is a major player. ANSP provides air traffic control, which involves securing the safety in the air and on the ground. Maintaining separation between the different planes is one of the factors in safety. The planes need to have a certain distance, horizontal and vertical, to each other, to eliminate the risks of collisions. Next to ANSP other stakeholders can be defined. Government, airports, airlines, and Eurocontrol are important stakeholders that are described in this paragraph.
All the stakeholders contribute to the capacity of the gate-to-gate chain in their own way. This can be in the form of constraints or adjustments. A stakeholder can adjust something to the gate-to-gate chain in a positive way, so it helps to increase the capacity or the efficiency, but a stakeholder can also
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produce limitations to the capacity or efficiency, for example by regulations introduced by the government.
ANSP
The air space structure is divided into several control sections. These are the control zone (CTR), the terminal control area (TMA), and the Control Area (CTA), which consists of lower and upper air space (LAS/UAS)37. In each of these different control areas an ANSP is active. ANSP stands for Air Navigation Service Provider. An ANSP is the organization that separates aircraft both on the ground and in flight in a dedicated block of airspace on behalf of a state or a number of states. It can be a government department, state owned company or privatized organization. The Dutch National ANSP is LVNL (Luchtverkeersleiding Nederland)38.
The Control Zone (CTR) is an area that vertically stretches out from the ground to an established upper limit. It has a horizontal radius of 5 to a maximum of 8 NM39 around the middle centre of the aviation area. This area is controlled by three control centers: Clearance Delivery, Ground Control and Tower Control40.
The most important responsibility of the Clearance Delivery is to ensure the planes receive the right take-off time and flight route. Ground Control is responsible for the movement area of the airport, like runways and holding areas. Tower Control is responsible for the movements on runways as well as the air traffic near the airport.
The TMA is a controlled airspace set up at the contour of airports to protect climbing and descending traffic. The Approach Controllers (APP) operate in the TMA zone. These controlled zones cover the CTRs and can even control several airports.
On top of the TMA the Control Area (CTA) is situated. This airspace is divided into a lower and upper level, the LAS and the UAS. En route traffic controllers operate in centers called Area Control Centers (ACC). The responsibility of the ACC is to guide planes to their flight altitude and protect the safety distance between planes.
LVNL controls the Control Zone at Schiphol, the Terminal Area and the Lower Airspace. The Upper Airspace is controlled by Maastricht Upper Area Control Centre (MUACC). They are responsible for Benelux and the north-west of Germany. The workload of air traffic controllers plays a huge role in the capacity of the gate-to-gate chain, mainly in the en-route sector. All planes that fly in the airspace needs to be controlled by an ANSP, this can only be done when there are enough traffic controllers. At this moment the LVNL has a luxury position. It is a state owned company with no competitors. The 37 http://www.aviationwiki.nl/index.php/Luchtruimtestructuur 38 www.lvnl.nl 39 Nautical Miles 40
Belgocontrol; Air Traffic Control Belgium, website:
whole air traffic market is dependent of them: without air traffic controllers, no flight movements can occur. There are plans to redesign the airspace structure and combine national ANSPs to less European ANSPs. This can mean that LVNL has to give up their excellent position.
Government
V&W
The Ministry of Transport, Public Works and Water Management41 offers possibilities for air traffic growth, but within the constraints of safety, environment and noise. They produce legislation around those topics. Several rules have been constructed by European government, but due to the scope of this research, these are not defined as separated stakeholder.
The most important law is the Civil Aviation Act42. This law contains all regulations about noise, air pollution, emission, etc. Next to this there is the “Luchthavenverkeerbesluit Schiphol43”, this is an ordinance for Schiphol that contains limits to pollution and emission. In European legislation the regulation around CO2 emission is established. The Dutch government has enlisted this law. Another important factor is safety, for the planes and their passengers, as well as for the society.
The Dutch government acknowledges that growth of Schiphol and thereby air traffic, is good for the national economy, in particular for tourism, job opportunities and charged fees. The government has benefits from a well working air traffic market, but on the other hand they also have to look after the members of the society. Neighbors of airports need to be protected against noise pollution, and the environment against CO2 emission. Herefore the government limits the growth by some constraints. The government has to find the right balance between economical benefits and damage to the environment. The Dutch government can be defined as a stakeholder in the whole gate-to-gate chain.
IVW
IVW is the inspection of the ministry Transport, Public Works and Water Management. IVW controls the regulation for air traffic. This is done by inspections, licenses, and knowledge sharing. They supervise airlines, maintenance and production companies, airports, air traffic control, and education institutions. The behaviour of airspace consumers is also controlled. Goal of the supervision is to reduce the chance on accidents, environment pollution, and interrupted market dimensions.
IVW controls the legislation made by the ministry of Transport, Public Works and Water Management and international government.
Military
41
Ministerie van Verkeer en Waterstaat
42
Luchtvaartwet, since 1958, Website:
http://www.vlinderstrik.net/documenten/Schiebroeksepark_Rooivergunning_Toeg_Luchtvaartwet.pdf
43
Luchthavenverkeerbesluit Schiphol, 2002, Website:
The military aviation uses a specific part of the airspace. This part is reserved for practicing and testing, and may not be used by the civil air traffic. Because of this a free flight is not possible. Planes cannot fly straight to there destination. They need to fly a specific route defined by ATC, to avoid military regions. Ministry of defence is responsible for the military aviation. The military is a stakeholder in the en route flight phase.
Eurocontrol
Eurocontrol is the European Organization for the Safety of Air Navigation. It is a civil and military intergovernmental organization that is focused on making the European aviation safer, more secure and more environmentally-friendly, by developing a uniform pan-European ATM system. Eurocontrol integrates all aviation stakeholders to achieve common goals. This integration is an important objective for Eurocontrol. Without collaboration and shared views their goals cannot be achieved. Therefore Eurocontrol introduced SESAR. SESAR is focused on collaboration between all stakeholders to make the air traffic flow in the air more efficient. It also involves the industry part of the aviation sector.
Besides the development of a new ATM system, Eurocontrol provides the slot allocations of the European airports. Each airline gets slots allocated to their flights. A slot is a scheduled departure or arrival time. Eurocontrol (CFMU44) allocates these times to the airlines based on airport and airspace capacities. Eurocontrol is mainly focused on the airspace side. It strives to a safe ATM network, to facilitate the growth of air traffic in Europe.
Airports
In this report we focus on Schiphol, so when talking about airports, we mean Schiphol. Airports are important stakeholders. Their infrastructure and operations play a huge role in the capacity issue. Schiphol would like to grow, for economical benefits, but due to regulations (environment/noise) Schiphol is very restricted in its growth. This not only brings congestion and delays, but in the long run also a threatened position in the air traffic market. Airlines can choose to fly to surrounding airports, and Schiphol could loose fees and customers. Transfer passengers can also decide to fly to other transfer airports. Schiphol’s competitive transfer position could be jeopardized. To make optimal use of the limited capacity, Schiphol requests the airlines to build more silent planes and less exploitation of night flights. The latter is done by differentiating the take-off and landing fees. Another measure is appealing priority for silent planes by the slot allocation. The limit of Schiphol’s capacity, due to regulations, is now 440.000 flight movements a year45. Schiphol wants to grow to 600.000 movements in 2020. This can only be realized when current regulation regarding environment and noise is adjusted.
44
Central Flow Management Unit: Air Traffic Flow Management is provided within Europe by the Central Flow Management Unit (CFMU) which is operated by EUROCONTROL.
45
