abcd: aircraft based concept developments work package …...itinerary: station 0 corresponds to the...

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ABCD: Aircraft Based Concept Developments

Work Package n°1

State of the art

Aircraft-Based Concept Consolidation

A D V A N C E D L O G I S T I C S G R

Madrid � Barcelona

EUROCONTROL

ABCD: Aircraft-Based Concept Developments

Date: 17/05/2007 Issue: 0 Rev: 1 Page: 2

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DOCUMENT IDENTIFICATION SHEET

DOCUMENT DESCRIPTION

Document Title WP1

Aircraft -Based Concept Consolidation

Abstract

This document describes the limits of the existing Flight-Based concept and processes, and introduces the necessity of a new approach which is identified in the definition of a new Aircraft-Based traffic concept.

Keywords CFMU Airport ATC ATFM Capacity Airlines Coordination CTOT Delay EOBT FPL Messages Slot Assignment Taxi time ANSP Turn around

CONTACT PERSON: TEL: DIVISION:

DOCUMENT STATUS AND TYPE

STATUS CATEGORY CLASSIFICATION Working Draft � Executive Task � General Public � Draft � Specialist Task � EATMP � Proposed Issue � Lower Layer Task � Restricted � Released Issue �

ELECTRONIC BACKUP

INTERNAL REFERENCE NAME:

HOST SYSTEM MEDIA SOFTWARE Microsoft Windows Type:

Media Identification:



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DOCUMENT CHANGE RECORD

The following table records the complete history of the successive editions of the present document.

EDITION DATE DESCRIPTION OF EVOLUTION SECTIONS /

PAGES AFFECTED

0.1 17/05/2007 Working Draft Creation All

1.0 30/06/2007 Final version All

1.1 11/07/2007 Final version All



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TABLE OF CONTENTS

1 INTRODUCTION...................................................................................................6

1.1 CONTEXT AND BACKGROUND ...........................................................................6 1.2 ABCD PURPOSE .............................................................................................7 1.3 PURPOSE OF THE DOCUMENT ..........................................................................8 1.4 STRUCTURE OF THE DOCUMENT .......................................................................8

2 GENERAL FRAMEWORK.................................. ................................................ 10

2.1 MAIN ACTORS ............................................................................................... 10 2.1.1 Airlines / Aircraft Operators.................................................................... 10 2.1.2 ANSPs – ATS Providers (incl. Airport Towers)....................................... 10 2.1.3 ATFM Providers..................................................................................... 10 2.1.4 Airport – Ground handlers...................................................................... 11

2.2 BASIC DEFINITIONS........................................................................................ 11 2.2.1 Flight vs. Flight Itinerary......................................................................... 11 2.2.2 Flight Plan ............................................................................................. 12 2.2.3 Minimum Time for Turn around (TTM) ................................................... 12 2.2.4 Stop Time .............................................................................................. 13 2.2.5 Slots ...................................................................................................... 13 2.2.6 Time phases.......................................................................................... 14

2.3 HIGH LEVEL EXCHANGE MAPS ........................................................................ 15

3 FLIGHT PLAN DATABASE............................... ................................................. 17

3.1 FLIGHT DATA ELEMENTS ................................................................................ 17 3.1.1 Flight Identifier ....................................................................................... 17 3.1.2 Time ...................................................................................................... 18 3.1.3 Position.................................................................................................. 18

3.2 FLIGHT DATA COMMON STRUCTURES .............................................................. 19 3.2.1 Schedules.............................................................................................. 19 3.2.2 Flight Plans............................................................................................ 19 3.2.3 Flight Progress Messages ..................................................................... 22 3.2.4 Aircraft position reports (ATC radar derived data and AO position reports– airborne phase)................................................................................................... 27

4 LIMITS OF EXISTING PROCESSES.................................................................. 29

4.1 INTRODUCTION.............................................................................................. 29 4.2 SCHEDULING OF AIR TRANSPORT OPERATIONS ................................................ 30 4.3 PRE-DEPARTURE DELAYS .............................................................................. 31 4.4 PREDICTION INACCURACY OF AIRPORT TURN AROUND TIME ESTIMATES ............ 32

4.4.1 Turn around times: lack of operating data.............................................. 32 4.4.2 Airlines’ strategy .................................................................................... 33

4.5 OPERATIONAL PERFORMANCE AFTER OFF-BLOCK ............................................ 34 4.6 COMMUNICATION GAPS BETWEEN INVOLVED ACTORS: AIRPORT OPERATOR, AIRLINE OPERATOR, ATC, CFMU ............................................................................. 34



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4.6.1 ATFM current limitations........................................................................ 34 4.6.2 ATFCM evolution................................................................................... 35 4.6.3 CDM studies.......................................................................................... 36

4.7 CONCLUSION ................................................................................................ 37

5 ABCD CONCEPT DESCRIPTION ........................... ........................................... 38

5.1 INTRODUCTION.............................................................................................. 38 5.2 ABCD ENVIRONMENT DEFINITION ................................................................... 39

5.2.1 CFMU Flight Plan database................................................................... 39 5.2.2 Roles and responsibility......................................................................... 40

5.3 ABCD OPERATING CONCEPT PRINCIPLES ....................................................... 43 5.3.1 Case of operations: flights between Lyon and Zurich airports ................ 44 5.3.2 Case of operations: flights between Rennes, Paris CDG and Southampton....................................................................................................... 49

5.4 ABCD INFORMATION MESSAGES .................................................................... 51 5.4.1 Airlines – data exchanges with the CFMU ............................................. 51 5.4.2 Airlines’ agents (airport) / ANSPs – “DEP” or “MVT” messages ............. 52 5.4.3 ANSPs – flight progress messages and actual position reports ............. 53 5.4.4 DPIs / FUMs / CDM messages .............................................................. 53 5.4.5 CFMU information broadcast ................................................................. 53

6 ABCD COST BENEFIT ANALYSIS: OVERVIEW............... ................................ 54

6.1 INTRODUCTION.............................................................................................. 54 6.2 PRIMARY DELAY AND REACTIONARY DELAY .................................................... 54

Who benefits from ABCD? .................................................................................. 56 6.3 COSTS OF IMPLEMENTING ABCD CONCEPT .................................................... 57 6.4 ABCD BENEFITS AND THEIR ESTIMATION ........................................................ 58

6.4.1 Slot Allocation mechanism improvement ............................................... 58 6.4.2 Enhanced planning of Airport and Ground Handling resources with respect to flight schedules................................................................................... 59 Thanks to the availability of on-line information about aircraft status there will be an improvement in the alignment between scheduled and actual use of airport resources. ........................................................................................................... 59 6.4.3 Improved Cost efficiency for Ground Handlers....................................... 59 6.4.4 Customer service................................................................................... 59 6.4.5 Better use of available capacity and increased impartiality in the slot assignment process ............................................................................................ 59

6.5 CONCLUSIONS .............................................................................................. 60



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1 INTRODUCTION

1.1 Context and background

Nowadays, air transport stakeholders (airlines, ANSPs, CFMU, airports) have established several processes, which aim at maximizing the use of available capacity while ensuring safety and a fair, transparent and non-discriminatory use of existing facilities. The two main processes are airport and ATFM slots allocations, since they deal with the main bottlenecks of the system: airports and airspace.

Each of these two processes has its own logic and sense: airport slot allocation process ensures the balancing of the airline’s strategic demand regarding the airport’s capacity, while the ATFM slot allocation process introduces the operational flexibility required in order to react to more tactical perturbations. These processes are complementary and take place at different chronological phases: the airport slot allocation process is ensured during the strategic phase, several months before the day of operations. The ATFM slot allocation process is operated during the day of operations, a few hours before real execution of flights.

The FPL (Flight Plan) management links the processes; through FPL aircraft operators transform allocated airport slots into EOBT (Estimated Off-Block Times) and collect all the relevant information about planned and actual flights. For flights within the European airspace, aircraft operators send to the CFMU a message (FPL) containing basic information about the flight in order to obtain clearance to over-flight, take off and/or landing at European airports. The aggregation of all FPLs, sent by airlines and handled by the CFMU, constitutes a “FPL database”.

With this definition, the FPL database provides a picture of the overall aircraft traffic, which is flying and going to fly over Europe in the future. This database is regularly updated upon the reception of messages, sent essentially by airlines to CFMU through the use of IFPS and through CDM (Collaborative Decision Making) at some major European airports and of course through the real aircraft position provided by radar. The FPL database is composed of individual flight plans, which are usually not linked to each other.

In the same time, it has been determined that when a delay appears on a given flight, part of this delay propagates for the flight using the same aircraft. In one of his previous study ADV systems has evaluated the impact of an ATFM delay on a daily itinerary on the Air Fance fleet by measuring the knock-on effect which could be defined as the cumulative delay due to the propagation of the ATFM delay throughout the itinerary.

The overall results are presented in Figure 1 below in which the knock on effects curves are represented for the occurrence of an ATFM slot at a given station and for sundry magnitudes of the ATFM delay.



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0.0

10.0

20.0

30.0

40.0

50.0

60.0

Statio

n 0

Statio

n 1

Statio

n 2

Station

3

Statio

n 4

Statio

n 5

Cum

ulat

ed k

nock

-on

effe

cts

(min

.)

10 m in. 20 m in . 30 m in. 4 0 m in . 50 m in.

Figure 1: Cumulated knock-on effects due to a singl e slot

In the figure above, the knock-on effects are shown for different legs of an aircraft’s itinerary: station 0 corresponds to the first leg of the itinerary, i.e. to the first airport of departure; station 1 corresponds to the second airport of departure (first airport of arrival) and so on.

The overall result shows that knock-on effects are not a constant proportion of the initial ATFM delay. For instance, a 20-minute ATFM delay allocated at station 0 generates approximately 15 minutes in knock-on effects whereas a 50-minute ATFM delay at the same station produces nearly 60 minutes in knock-on effects. In the same way, a 50-minute ATFM delay occurrence at station 2 will generate less than 20 minutes in knock-on effects.

Conversely, a slot allocated at the first, fourth or fifth station1 generates maximum knock-on effects.

Nowadays, because the FPL database is composed of individual flight plan not linked to each other, the CFMU could not foresee precisely (more than on stage ahead) what could be the impact of a delay on a given flight on future flights operated with the same aircraft than the one at which the delay occurred.

1.2 ABCD purpose

The aim of the ABCD (Aircraft-Based Concept Development) concept consists in using the aircraft registration, which is already a parameter of the FPL message, in order to link the individual flight plans of the CFMU FPL database.

Thank to this linkage, it will probably be possible to update in a more efficient way the CFMU FPL database and thus to provide a better picture of the future traffic flow over

1 Respectively number 0, 3 and 4 on the figure



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the European sky. The aim of the present document is to describe the ABCD concept and to analyse the benefits it could provide to air transport stakeholders.

1.3 Purpose of the document

The present document constitutes the first part of the project and intends to:

• Describe the state of the art of the FPL management: actors involved, basic definitions, actual strategies related to the management of the FPLs’ database;

• Provide for the current flight information context: description of the progress of flights; that is, flight schedules, flight plans, flight progress messages, and aircraft position reports;

• Assess the current limitations of the processes;

• Introduce the concept of ABCD, as a way to link the FPLs within the existing FPLs databases;

• Present some preliminary costs and benefits derived from the introduction of the ABCD concept.

As the development of the ABCD concept requires support among involved actors, including airlines, CFMU and airports, a number of interviews have been conducted. The interviews were aimed at getting the feedbacks about the ABCD concept.

The interview process has started with five airlines and one airport. Further interviews with more airports and CFMU are foreseen and will be presented in the follow up of this study.

In addition, a first version (draft) of the present document has been communicated to interested Eurocontrol research and operational areas. In particular, the comments that were received show the strong interest on the concept, from other areas than ATFM as well, such as the CRCO (Central Route Charges Office). Selective remarks from the CRCO are provided in the end of this document (Annex 6).

This document constitutes the base for the development of subsequent analysis within the project.

1.4 Structure of the document

The document is split in 6 sections and six annexes:

• Section 1 – Introduction – presents the context of the project and the purpose of the present document;

• Section 2 – General Framework – provides the state of the art to the following sections and subsequent analysis. The sections begins with a general overview of the actors involved and continues with a high level description of the processes, messages and actual strategies used in the FPL management;



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• Section 3 – Existing mechanisms for FPL database updates – describes the different activities related to the functioning of the FPL database, with particular focus on CFMU. The description presents how the database is updated through the flights’ life cycle;

• Section 4 – Limitations of existing strategies – presents the limitations inherent to the current FPL management processes. These could be grouped into the following categories: Airline’s flight scheduling, ATM processes before off-block, turn around processes, ATM processes after off-block and Communication Gaps;

• Section 5 – ABCD concept description – introduces the concept of ABCD;

• Section 6 – ABCD cost benefit analysis: overview – presents anticipated costs and benefits resulting from the implementation of ABCD.

A set of relevant airlines (including Air France, Ryanair, Airlinair, Onair and Iberia) have been interviewed to obtain their requirements and expectations regarding ABCD concept:

• Annex 1 – is the report of the interview held with Airlinair (French regional airline).

• Annex 2 – is the report of the interview held with On air (Italian low cost airline);

• Annex 3 – is the report of the interview held with Air France (French major carrier);

• Annex 4 – is the report of the interview held with Ryanair (Major low cost carrier);

• Annex 5 – is the report of the interview held with Iberia (Spanish major carrier).

Comments have been provided by Eurocontrol research and operational areas:

• Annex 6 – presents the feedback and comments received from the CRCO on the ABCD concept.



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2 GENERAL FRAMEWORK The objective of the present section is to provide a context to the following sections and subsequent analysis. The section begins with a general overview of the actors involved and continues with a high level description of the processes, messages and actual strategies used in the FPL management.

2.1 Main actors

2.1.1 Airlines / Aircraft Operators

As private for-profit companies, airlines strive to satisfy their business objectives and optimise their operations by determining the optimum flight departure and arrival times as well as flights routes and levels. Therefore, a prerequisite to any airline operations consists in convenient take-off, landing and over-flight rights. This accounts for the importance given by airlines to slot allocation procedures.

Different kind of airlines (flag carriers, low cost, charters), may have different priorities but in general, the ability to operate to published schedules punctually and efficiently is essential. These schedules involve a myriad of connecting and interdependent flights and events. The resources (aircraft and flight-crew) used for a particular flight form part of a continuous inter-connected process in which delay can have a serious and growing effect on subsequent flights.

2.1.2 ANSPs – ATS Providers (incl. Airport Towers)

ATC’s main goals are to prevent collisions between aircraft and to expedite and maintain orderly flow of air traffic while maximising the use of available capacity. These objectives can be achieved by applying separation between aircraft and by issuing clearances to individual flights as close as possible to their stated intentions within the general framework of ATFM measures and according to the state of ATM environment (airspace status, ATC sectors configuration, airport infrastructure, weather, etc).

ATS Providers play an important linking role between involved actors: they issue the ATC clearance that normally includes possible ATFM delays, provide airports with actual flight data and provide the airport coordinator with the available ATC capacity.

2.1.3 ATFM Providers

In the following of the study, ATFM providers encompass CFMU along with FMPs. ATFM main objective is to contribute a safe, orderly and expeditious flow of air traffic by ensuring that ATC capacity is used to the optimum extent possible, and that the traffic volume is compatible with the capacities declared by the appropriate ATS authority.

The emphasis of ATFM is on balancing the management of capacity and demand, planned strategically and applied tactically as a result of physical airport or airspace limitations. ATFM will be one of the primary means of ensuring flight punctuality and efficiency.



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ATFM Providers must contribute to demand/capacity balancing based on cooperation with AOs and ANSPs and allocations of slots, while maintaining the system’s integrity. To do so, they receive (through IFPU) and process the Aircraft Operators requests (FPLs) considering the state of ATM environment (airspace status, route network availability, ATC sectors configuration, airport infrastructure, weather, etc).

ATFM providers prepare these activities in the strategic/pre-tactical phase and their responsibilities culminate in the tactical/operational phase, managing the actual flights plans and flows and integrating as far as possible real time events and conditions. The optimal development of these activities requires accurate and updated information from involved partners (airports, airlines and ATC).

2.1.4 Airport – Ground handlers

In the following of this study, “airport” encompasses the different partners at the airport responsible for the management of the airlines’ turn around activities (i.e. ground handlers).

Each airline has “agents” (airlines’ staff or other staff – ground handlers to which the tasks are subcontracted), at the airport responsible for the disembarkation and boarding of the passengers, baggage handling, refuelling, safety checks on aircraft, etc.

These agents strive to manage their activities to comply as close as possible with the “scheduled” flights’ programme, the one “sold to the clients”.

Punctuality is objective n°1 of the agents. In case of delays, the procedures to manage the delays could be different depending on the strategy of the airlines, but most of them share a common objective: come back to the scheduled flights’ programme. This could imply flights’ cancel or aircraft’s permutation strategies, if a delay implies a risk of significant propagation.

2.2 Basic definitions

Given that the study tackles concepts concerning airports, airlines and ATFM, the terminology that is used is a fusion of airports, airlines and ATFM terminologies. These terminologies have many points in common but they also have some divergences and even some contradictions. This section intends to assemble some basic definitions in order to avoid possible confusions and set up a general understanding.

2.2.1 Flight vs. Flight Itinerary

In ATM terms, a flight is an aircraft departure from an airport followed by its arrival at another airport, with no intermediate touchdown point’s in-between.

By contrast, we could define the term “flight itinerary” as the set of concatenated flights, in which the departure airport for the next flights is the arrival airport of the previous flight, except for the first leg of the itinerary.



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Today, the basic unit of existing ATM systems, including CFMU, is “flight”. Therefore, we define the existing processes, data structures, etc. as “flight-based”. In the ABCD concept, the reference would change to the aircraft, and some processes would thus be referred as “aircraft-based”.

2.2.2 Flight Plan

For flights within the European airspace, aircraft operators send to the IFPU (Initial Flight Processing Unit of CFMU) a message (FPL) containing basic information about the flight in order to obtain clearance to over-flight, take off and/or landing at European airports.

According to ICAO’s Document 4444 and to EATMP Glossary, the Filed Flight Plan (FPL) “is the flight plan as filed with an ATS Unit by the pilot or a designated representative, without any subsequent changes” and the Flight Plan “contains specified information provided to Air Traffic Services Units, relative to an intended flight or portion of a flight of an aircraft”. The current flight plan (CPL) is “the flight plan, including changes, if any, brought about by subsequent clearances”.

For the tactical phase analysis, we will consider the FPL as the initial Flight Plan sent by the Aircraft Operator to an IFPU that contains information about an intended flight:

• Origin and destination airport;

• Aircraft registration and type;

• EOBT: estimated off block time;

• ETA: estimate time of arrival;

• Flight profile (including flight path within route network);

• Detailed flight schedule (estimated time over ATC points);

• etc.

Approaching the time of operation, flight plans may change as they take into account real time events. Initial FPL messages can be followed by flight plan revision messages.

For flights that take place on a regular basis, aircraft operators can send once a RPL (repetitive flight plan), containing the same basic information, which applies to all flights with the same characteristics. According to ICAO’s Document 4444, the RPL is “a flight plan related to a series of frequently recurring regularly operated individual flights with identical basic features, submitted by an operator for retention and repetitive use by ATS units. 20 hours before the EOBT, RPLs are transformed in FPLs and are processed with the rest of FPLs.

2.2.3 Minimum Time for Turn around (TTM)

The “TTM” is the minimal time for turn around necessary for the aircraft operations at the airport. They include activities of refuelling, handling, boarding and deplaning of passengers, etc.



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The “TTM” is a time window between the “in-block” time and the “off-block” time.

Given that the aircraft types are of different size, the TTM may vary from 20 minutes (case of small aircraft types) to up to one hour and a half (case of the major aircraft types). For example, when the aircraft type is “heavy” (e.g. case of a Boeing 747), the airlines have to define a “TTM” of more than one hour.

The compliancy of the time estimates for departure / arrival with the TTM is of high importance for the airlines. The major consequence brought about by a non compliant definition of the time estimates according to the TTM reserved at each of the airports may be the generation of delays.

2.2.4 Stop Time

Airlines organise the different legs of an aircraft’s journey (aircraft’s schedule) by defining a “stop” time for turn around.

In the context of this study, the scheduled time allocated by an airline for turn around will be referred as the “stop time”.

The “stop time” is defined for a given aircraft type, as the scheduled time between the arrival of the aircraft at the airport (in-block) and the departure of the aircraft from the same airport (off-block).

The “stop time” has to be higher than the “TTM” (mi nimum Time for Turn Around).

If the “stop time” is higher than the TTM, a delay occurring on one flight can be absorbed during the turn around: if the TTM plus the delay are lower than the stop time, the delay is not propagated downstream, to subsequent flights.

2.2.5 Slots

Nowadays, there are two types of scheduling regulations for organising flights. These are the airport slots and ATFM slots. Slots are allocated to each flight, i.e. a slot is “an arrival or departure time window reserved for a flight”. Several months before the day of operations, some airports have to limit the airlines’ demand so that the number of schedules flights does not exceed the airport declared capacity. This process corresponds to the “airport slot” allocation process. This process is currently organised around two scheduling seasons: the summer season, corresponding to the Northern summer, and the winter season, corresponding to the Northern winter.

As the day of operations approaches, different factors account for the fact that, in some cases, airlines’ demand (represented by FPLs and RPLs) exceeds the airport and/or the airspace capacity; in these cases, the ATFM regulation process smoothes real demand so that the number of flight does not exceed the airport or the airspace real time capacity (throughput).



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ICAO Document 7030 defines the (ATFM) slot as the calculated take-off time (CTOT) delivery resulting from a slot allocation message (SAM). Actually, this CTOT is valid during the time window going from the CTOT to CTOT + 10 and ATC may also use the previous 5 minutes. Consequently, the ATFM slot definition for ATC that is going to be used in this study is the following: “the time window going from CTOT to CTOT + 10’ (plus a gap of 5’ before CTOT for ATC purposes), allocated by the CFMU for an aircraft movement on a specific date“. The ATFM slot gives clearance of take off, and/or landing and/or over-flight a sector to a given flight.

2.2.6 Time phases

The process that leads to the successful flight operations starts months before the actual flight. This period of time is usually divided in different time phases:

• Strategic phase ; starting several days / weeks before the flights day of operations and ending before the day of operations.

• Pre-tactical / Tactical phase ; starting the day before the flight day, and ending with the Aircraft Operator FPL’s submission to CFMU (on the day of operations, at least 3 hours before departure);

• Tactical / Operational phase ; between 3 hours before departure (EOBT) and departure (EOBT);

• Active phase (almost airborne or airborne phases); starting at the moment, the aircraft is ready to depart (e.g. all passengers on board and all doors closed).



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2.3 High level exchange maps

Figure 2: High level exchange map – relations betwe en actors

Figures 2 present a simplified diagram of the current information exchanges between air transport stakeholders that take place in different time horizons. As highlighted in the previous paragraph, this information process starts several months before the beginning of a winter or summer season, when the airport coordinator collects the necessary information to allocate the available airport slots (actual movements of previous season, airport / ATC capacity restrictions, airlines requests, etc.).

FMPs

TWR / ANSPs

ATCO clearances

Flight progress updates

Real Time positions

Taxi times

Capacity constraints (sectors, runways)

CFMU

FPLs

ATFM Slots

Traffic loads

Aircraft Operators

Flight Plans

A/C registrations & types

Priority of flights

Turn Around times

Delays

Airport / Ground handlers

Airport slots (scheduled

times)

Stand & gate allocation

Capacity constraints (stands)

FPL / RPL messages FPL messages Flight Progress

messages ATFM Slot

Validated FPL messages

Copy of ATFM slot Traffic loads

Flight Progress messages Real Time

position reports

Actual Arrivals / Departures

Airport slot

Landing / departing requests

Capacity constraints Resource planning

(stand & gate)

Capacity constraints

ATFM reg. requests

Strat / Pre-tact

Tact / Active



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When the airport slots are allocated to the Airlines, the commercial schedules are established. Based on these schedules, airlines send their flight plans to the CFMU (IFPS), in the form of RPLs or FPLs.

On the day of operation, the CFMU issues ATFM slots that are sent to ATS Units and airlines. The most significant data concerning the actual flight (actual departure and arrival times, etc.) are collected by ATS Units and sent to CFMU and to airports, which use them to update the planning information.

Figure 3: Process-based overview of Flight Data Man agement

Figure 3 is a variation of the current flight information exchanges view in that it takes a time-based process view of the management of flight data.

Strategic Phase Pre-tactical Phase Tactical Phase Active Phase

Airport (coordinated) Airport Capa. Declar. – Airport slots allocation

Aircraft Operator

Commercial Scheduling

CFMU

Strategic ATFM Capacity planning

Airport Slot FPL/RPL ATFM slot Position reports

Flight Progress Msg slot

Airp ort – ground h.

Turn around processes (Stand)

Aircraft Operator

Flight planning

CFMU

Pre-tactical ATFM Flight Plan Distribution

Airport (coordinated)

Airport scheduled slots adjustments

Aircraft Operator

FPL update (turn-around, a/c substitute.)

CFMU

ATFM Slot allocation

CFMU

Flight Progress updates

ATS Units Regulation activations / adjustments

ATS Units Active flight planning Radar surveillance

Airport – ground h.

Estimated arrival times updates

Aircraft Operator

Active flight

ATS Units

ATC Capacity declarations

ATS Units Regulation requests / Capacity adjustments

DATA STRUCTURES: INFORMATION ON FLIGHT STATUS



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3 FLIGHT PLAN DATABASE

3.1 Flight data elements

As previously described, existing traffic progress information processes are focused on flights. Their structures centre on data uniquely identified for each flight. These data are associated with several aspects, about a flight.

These aspects are mainly related to the three following categories of data:

• Flight Identification: unambiguous identifiers of the entity “flight”.

• Time: time estimates of the scheduled events to occur; actual times; etc.

• Position: representation of the aircraft’s 2D (airport, route) or 3D (level) positions.

3.1.1 Flight Identifier Actors have different standards to identify the flight. A first and common identifier is the flight number or call sign, for example “AF401”. However, that identifier is often not sufficient for an unambiguous identification of a flight, for the following reasons.

First, the same flight number may be in use by two flights simultaneously. This is the case for example, when an airborne flight reports flight progress messages, while a flight plan message is stored for the next leg of the flight (which shares the same flight number).

Second, flight numbers are reused day after day, so that, at a minimum, date is additionally required to achieve uniqueness.

Finally, for some airlines, the flight number is the reference for the flight itinerary during the entire day (i.e. the succession of take offs and landings during the aircraft’s daily journey) rather than the reference for a single flight. Therefore, actors do consider additional elements to achieve “uniqueness”. For example, they consider a set of identifiers such as {flight number, departure airport, arrival airport, departure date}. In this way, the identifier is a set of “natural” flight plan data, which unambiguously identify the flight. In addition, it conveys direct information about a particular flight.

Another option is the system-generated flight identifiers, which are used by flight data processing systems. These bring the advantage of being unique, controllable, always available, and universal, i.e. that cover all flight types. A drawback is that such an arbitrary identifier contains no “natural” data and thus conveys no information about a particular flight.

Therefore, on the one hand, human actors such as controllers use the set of natural identifiers previously described. On the other hand, flight data processing systems use system-generated IDs such as the “IFPLID”. IFPLID is created by CFMU IFPS and is used in the frame of data exchanges between CFMU IFPS/ETFMS and ATS Providers systems.



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In the new context of ABCD (“aircraft-based”), a candidate key is the aircraft tail number or aircraft registration, complemented by the date of departure. This option brings the advantage of covering all aircraft. More over, it allows to unambiguously identifying the “flight itinerary” of the aircraft during the entire day. A drawback is that tail numbers are sometimes not available in advance and may change when aircraft are substituted during the course of a flight itinerary.

Considering the aircraft tail number option, there may be as many as three different contexts in which this key could be applied.

First, the case of the “flag-carriers” or major airlines operating with a hub is representative of the “substitution” issue here-above mentioned. These airlines do require keeping flexibility for aircraft substitution, at least at their hubs, and until a period close to the departure. Thus, a unique “aircraft-based” ID for major airlines is complicated and it seems that we would need to keep the “flight-based” ID option at least to cover the cases when an aircraft is substituted during the course of a flight itinerary.

The second type of airlines in which the “aircraft-based” option would be applied is the so-called “low-cost” airlines, such as Ryanair and Easy Jet. Those airlines have been growing in importance. Today, they capture a significant proportion of European traffic and thus are worth to be considered. For these airlines, which operate “point to point”, aircraft substitution is rarely applied since the entire aircraft fleet is continuously operating. Then, the “aircraft-based” ID is convenient and could be available in advance at a moment where the aircraft allocation programme is established.

The last type of airlines is the case of smaller airlines, general aviation, and other non-scheduled airline types. For these types of airlines, the aircraft fleet is small (in number), and aircraft substitution is rarely applied as well. Then, we could envisage using the “aircraft-based” ID option, which would be available in advance as soon as the aircraft allocation programme is defined.

3.1.2 Time

The management of time is a fundamental aspect of ATM operations. In tracking flight progress, time is used in two basic ways. First, time represents when an event is scheduled to occur, such as scheduled flight departure (e.g. off block time estimate).

The second way in which time is used is for reporting the actual events occurrences, such as actual take off time. These data are important to assess whether the flight progresses according to plan or not. If deviations are observed, the system will re-calculate the future trajectory of the flights, and will update the plan accordingly.

3.1.3 Position

Another fundamental type of data in ATM is position, or location. This applies to aircraft position using the three dimensions of latitude, longitude and altitude.

There are different ways in tracking the aircraft position. First, position can represent the geographic coordinate projections for latitude and longitude of the aircraft and level if the aircraft is airborne.



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The second way is to make a link between an aircraft position and a waypoint or between an aircraft position and a 2-dimensional ground-based facility location, such as an airport or a NAVAID. In this way, the aircraft’s trajectory is regarded as the succession of waypoints/locations along the itinerary.

3.2 Flight data common structures

Through existing common data structures, a large amount of flight information is exchanged: flight identifier, position, time categories of information.

There are currently four types of common structures. The first two types refer to the “planning” status of a future flight: scheduled (strategic phase) and planned (tactical and pre-tactical phases). The other two types refer to the “active” status of the flight: flight progress messages and actual position reports (active phase – almost airborne or airborne).

3.2.1 Schedules

Several months before the beginning of the season, the airline commercial department sketches out routes taking into account issues such as:

• The marketing opportunities and priorities;

• The availability of over-flight rights;

• The slots availability at departure and destination airports;

• The aircraft efficiency for the distance/route to be flown.

The result of this activity is a desired commercial schedule. With this desired schedule, airlines send corresponding airport slots request to airports of departure and arrivals.

At this early strategic stage, the information about the future flight is generally very light. The available data is the following:

• Flight Identifier: {Aircraft Operator, Departure airport, Arrival airport, Airport slots}.

• Time: Date, Scheduled Off-block time (airport departure slot), Flying time, Scheduled In-block time (airport arrival slot);

• Position: Departure airport, Arrival airport.

3.2.2 Flight Plans

According to the EATFMP glossary, “Flight Plans contain specified information provided to Air Traffic Services Units, relative to an intended flight”.

Flight plans are prepared by the AOs, in conjunction with CFMU at different time anticipation levels, before departure of the aircraft. There are different variations of Flight Plans that take an important role:



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• Pre-tactical Flight Plans (FPL / RPL) ;

In the pre-tactical phase, airlines create detailed operational flight plans (OFPLs) that are used firstly for planning purposes (crews, aircraft, maintenance, etc.). Airlines (or the service providers to which the task is outsourced) may have sophisticated tools to create optimised flight plans. Criteria for optimisation are primarily fuel consumption and flight time. Parameters such as winds, temperatures, cost of route charges and expected load may be taken into account.

Once the OFPLs are established, airlines prepare a reduced version of flight plan for submission to CFMU / IFPUs (including origin and destination airport, aircraft registration or call sign, aircraft type, EOBT and ETA), in the form of an ICAO FPL2.

In the case of flights operating on the same day(s) on consecutive weeks, airlines have the possibility of submitting RPLs to CFMU. RPL data will automatically generate individual FPLs in the CFMU system, thus implying a reduction of filing work. However, RPLs may not take into account particular environmental conditions that may apply on the day of operation, when they are created.

Twenty hours before EOBT, RPL take the form of a FPL into the CFMU system. In the absence of any RPL, airlines are requested to submit a FPL version with 3 hours anticipation before departure at the least.

At this phase (pre-tactical), FPL / RPL data is the following:

• Flight Identifier: {Flight Number (Call sign), Departure airport, Arrival airport, departure date}.

• Time: Estimated Off-block time, Flying time, cruise speed(s), Estimated In-block time;

• Position: Departure airport, Arrival airport, routes, waypoints, cruise altitude(s).

• Other: Aircraft Operator, Aircraft Type, Aircraft Tail number.

• Tactical Flight Plans (FPL, ATFM slots);

If a flight is subject to ATFM regulation(s), the concerned airline receives an ATFM slot (CTOT – calculated take-off-time) 2 hours before EOBT. If the airline thinks the delay can be reduced against its operations, the airline will make adjustments to the FPLs and submit changes to CFMU (changes in routes, flight levels). If not, they accept the slot and integrate the information into their operational flight plans.

As the CFMU system processes the flight progress messages and actual aircraft position reports of the other flights (which may deviate to their plan), an allocated ATFM slot could eventually be improved until a few minutes before take off. If an improvement is made available, CFMU can provide the airline with a more convenient slot. The Flight plan is updated accordingly.

2 Submissions of FPLs / RPLs (ICAO format) are a prerequisite to any airline operations within the controlled European airspace



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By default all flights will be in the status called RFI (Request for Improvement). This RFI default status may be changed to SWM status by sending the SIP Wanted Message (SWM). In case the improvement is possible, the AO will receive the Slot Improvement Proposal (SIP). The AO may accept or refuse the new CTOT via a Slot Proposal Acceptance message (SPA) or a Slot Rejection message (SRJ).

For flights having already received their slot and being in a situation to depart before their CTOT, the AO may ask local ATC to send a Ready (REA) message. REA may be sent between EOBT-30 min and CTOT. If an improvement is possible, it will be provided with a Slot Revised message (SRM).

At this phase (tactical), flight data is enriched with additional information, as the following:

• Time: departure taxi duration, take-off-time (includes eventually ATFM slot);

• Position: SID (Standard Instrument Departure procedure), take-off runway.

• ATC Flight Plans

Each ATS Flight Data Processing System (FDPS) concerned by the flight receive the corresponding flight plan from the CFMU / IFPS, in the form of an electronic message. The FDPS processes each message and establish a database for flights (ATC Flight Plans), where relevant sub-sets of flight plan data are stored for use by strip printing, display, printout, and inter-facility data transfer functions.

At a fixed time before the transfer of an airborne aircraft between two ATS Units, the transferring unit send updated planning data about the flight (ATC Flight Plan updates based on actual trajectory reports) to the receiving unit, thus providing the controllers with accurate information.

An ATC Flight plan contains the following item of flight data:

• Flight Identifier: 1. IFPLID or any other system-generated ID; 2. “natural” identifier such as {flight number, departure aerodrome, SSR code};

• Time: Coordination time (ATS Units boundary), Estimated times over waypoints, speed; Estimated landing;

• Position: Route data (portion of the flight which is of ATS Unit’s concern), Requested altitude (derived from the initial flight plan sent by CFMU / IFPS), Assigned altitude (active altitude assigned to the aircraft), Coordination waypoint (ATS Units boundary), STAR;

• Other: Message type (e.g. CFMU/IFPS Flight Plan, ATC upstream Flight Plan), Aircraft Operator, Aircraft Type, airborne equipment, Aircraft Tail number.



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3.2.3 Flight Progress Messages

In its role of central flight plan processor and distributor in ECAC, CFMU {IFPS; ETFMS} receive and transmit many messages from/to the other actors: AOs, ATS Providers and ATS Providers. These can be split into the following categories:

• Flight status reporting messages :

Flight status reporting messages are sent to indicate whether the aircraft is on the ground or is airborne. There are two main classes of reporting messages:

- DEParture:

According to ICAO rules, departure (DEP) messages shall be transmitted for all flights as soon as practicable after the aircraft is airborne.

In Europe, DEP message is sent from the ATS Provider responsible for the area surrounding the airport of departure to CFMU. In certain countries such as France, airlines do also receive a copy of DEP messages, which allow them to be aware of any delay that may occur at take-off. However, not all the airlines in Europe do process DEP messages, as it is the case, for certain airlines, in Spain.

When DEP messages are transmitted, actors have the confirmation that the flight is “airborne”.

For example, upon reception of this message, the status of flight plan changes within IFPS and ETFMS databases, from “filed” status (case of non regulated flights) to “ATC activated” status or from “Slot Issued” status (case of regulated flights) to “ATC activated” status3.

Note: As it has been mentioned, not all the airlines do receive a copy of DEP messages, issued from the ATC. Still, they have other means to be informed of the actual take off times. For example, certain airlines have defined other processes for exchange such information. These are based on other type of messages (such as MVT – Movement), similar to “DEP”, with the exception of the sender. For example, a MVT message is transmitted from an airline’s agent (e.g. ground handler) at the airport of operations to the airlines’ operational control centres.

- ARRival:

Just as with departure, arrival (ARR) messages are transmitted as soon as practicable after the aircraft has landed.

In Europe, ARR message is sent from the ATS Provider responsible for the area surrounding the airport of arrival to CFMU. This confirms that the flight is “landed” and means a flight plan closure.

3 The different statuses defined within CFMU systems are: 1. “Filed” (Basic status), 2. “Filed_Slot_Allocated” (Flight is regulated but the slot has not been published yet), 3. “Slot Issued” (Flight is regulated and the slot has been published), 4. “Tact_Activated” (ETFMS assumes the flight is airborne, but it has not yet received a confirmation from ATC (DEP message)), 5. “ATC_Activated (ETFMS has received a DEP message from ATC), 6. “Cancelled” (Flight has been cancelled by the AO), 7. “Terminated” (ETFMS considers the flight terminated), 8. “Suspended” (The flight has been suspended).



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Upon reception of this message, the status of flight plan is set up at “terminated”.

• Flight progress messages :

Flight progress messages are exchanged between CFMU and the other actors at several instants of the flight’s life cycle. They provide the different systems with early updates about flight data, thus improving the performance of the actors in managing flights.

ATS units send AFP and FSA messages to inform CFMU about flight plan updates and progression of airborne flights. Airports send DPI messages to CFMU, which inform about the progress of aircraft’ turn-around processes.

CFMU uses these messages to create and update its flight data and send ACH, EFD and FUM messages in return to the concerned actors.

- AFP / ACH: ATC Flight Plan Proposal Messages:

The AFP message is sent by an ATC Unit to CFMU / IFPS when one of the following events occurs: a flight plan is missing, the route or flight levels have changed (ATC downstream trajectory portions are affected), the aircraft type – as filed by the airline – is inconsistent.

The message enables downstream ACCs to be provided with accurate updates to the flight plans held in their databases, thus improving their traffic situation awareness. It also enables CFMU / ETFMS to update its traffic information, thus providing more accurate sector load calculations.

The AFP message is processed by CFMU / IFPS, which distributes ACH messages in reply to the downstream ATC units and CFMU / ETFMS.

- FSA: First System Activation message:

The FSA message is sent by an ATC Unit to CFMU / ETFMS in the following circumstances: 1. just after aircraft’s take-off, 2. when the route is changed within an area of responsibility of one ATS Unit, without affecting another ATS Unit’s area (otherwise, the message to be sent would be an AFP), and 3. when time estimates modifications are higher than 5 minutes.

The FSA will supply CFMU / ETFMS with the actual take-off time (ATOT) from the aerodrome of departure or with estimated time, level and point of entry into the airspace of the ATS Unit’s area of responsibility. This information is used to update ETFMS flight data, in order to get a more accurate prediction of the sector counts.

- EFD: ETFMS Flight Data Message:

The EFD message is sent by CFMU / ETFMS to ANSPs that are interested in receiving a copy of the flight data available within ETFMS. The purpose of the EFD is to inform users about the latest state of a flight in ETFMS and it is basically composed by the flight profile elaborated by the ETFMS.



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This message may be sent upon ATS Units’ specific request, at regular intervals or upon reception of flight progress messages such as FSA, AFP and APO. The first event at which the message will be sent is the flight plan creation and its distribution will end when the status of the flight changes to Terminated, cancelled or suspended.

- DPI messages:

DPI messages are a set of coordination messages whose objective is to better co-ordinate ATFM with Airport Operations in order to ensure on time update of the flight data more consistent slot calculation and improve slot adherence. These are provided from any of the airport operational actors (incl. airport operator, handlers, and aircraft operators) to CFMU (actually DPI messages are sent by ATC systems, DMAN systems or CDM systems). Their purpose is to ensure on time update of the flight data, more consistent take-off slot calculation, and slot adherence improvement. There are three types of coordination phases defined: planning phase, turn-around phase and ATC pre-sequencing phase.

The planning phase is the phase where all airport slots and flight plan estimates are made consistent. Ghost flights (i.e. flight plans submitted which have no corresponding flights within the airspace) and duplicated flights are suppressed.

The turn around phase is the phase where the airport actors will provide CFMU with realistic estimates of the take-off times.

The ATC pre-sequencing phase is the phase where the aircraft is controlled by the tower, which delivers the clearances for engine start-up, pushback, taxiing, and take-off. During this phase, ATC will provide to CFMU an accurate estimation of the actual take-off time.

Each of these phases has a specific type of DPI message:

o Planning phase: Early-DPI (E-DPI)

E-DPIs are sent by the airport’s system to CFMU after verification of the flight plan EOBT with the airport slot and as such confirm the ICAO FPL message. It also provides CFMU/ETFMS with the first estimate of the taxi-time and the SID, if available.

o Turn-around phase: Target-DPI (T-DPI)

The Target-DPI provides CFMU/ETFMS with an earlier take off time without taking into account the ATFM regulation if any. This value allowing the CFMU to compute the best slot improvement when it is possible,

o ATC pre-sequencing phase: ATC-DPI (A-DPI)

The ATC-DPI provides CFMU/ETFMS with the latest estimation of the take-off-time. It is based upon the take-off-sequence of the flight and it is sent at delivery of the push-back clearance.

Each DPI serves a specific purpose and is sent at its appropriate time frame. The time frames of the DPIs are:



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DPI-Type Filing time frame

E-DPI 3 – 2 hrs before EOBT

T-DPI 2 hrs – 30 min. before EOBT

A-DPI 30 min. before take-off

Table 1: DPIs

Each DPI message provides CFMU/ETFMS with: a taxi-time, the SID, and also, eventually the aircraft type and aircraft tail number (aircraft registration).

- FUM message:

The FUM message is a message sent by CFMU to any other actors interested in receiving early updates of the progress of the flight. Its main purpose is to supply the airport of destination and aircraft operator with an estimated landing time (ELDT). Another purpose is to provide an ATS Unit with the estimated time of entry of a flight into its airspace of responsibility.

The FUM is sent for the first time 3 hours before landing time. Then, it will be sent to the users at significant updates of the flight in the CFMU/ETFMS system.

Notes:

1. Today, the interface description of DPI and FUM messages has been finalised.

2. However, implementation of the DPI and FUM messages on airport operations has not been achieved and is still under discussion;

3. DPI and FUM messages would only concern a limited number of “CDM-compliant airports”, at least for the short-term;

4. Munich airport has already executed several CDM-trials so far. The Munich airport is currently finalising implementation phase and can be regarded as one of the most advanced airports regarding the implementation of DPI and FUM messages.



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The following table displays the data elements per flight progress message:

Cat Data element AFP /ACH FSA EFD DPI FUM

ICAO FPL data elements

(ID, time estimates, routing estimates) X X X X

I D

IFPLID (System-generated ID) X X X X X

Actual Off-block-time X

ATFM slot X

Estimated Take-Off-Time X

Target Take-off-time X

Anticipated actual take-off time (latest estimation provided by the A-DPI message) X

Actual take-off time X X

Time estimates over the detailed further routing positions X X

Time estimates over airspace entries / airspace exits X

Holding time estimates X

Time estimate over STAR entry point or last point of route X

T I

M

E

Estimated landing time X

Detailed estimation of the further routing of the flight:

Co-ordination points, direct routes, ATS routes, waypoints, holdings area, flight levels over waypoints

X X

SID X X X

STAR X X X X

P O S I T I O N

List of airspaces crossed X

ATFM status of flight

(filed, slot issued, ready, activated, etc.) X X

DPI status

plan; turn-around, ATC pre-sequence X

O T H E R

List of ATFM regulations X



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3.2.4 Aircraft position reports (ATC radar derived data and AO position reports– airborne phase)

This section describes the messages received by CFMU/ETFMS regarding the reports about actual airborne aircraft positions. ATS Units provide those actual positions in the form of CPRs (Correlated Position Reports). CPRs contain radar derived data.

AOs, also provide position reports in the form of APR (Aircraft Position Report). The APR gives the actual position of airborne long-haul aircraft before the flight enters the CPR coverage area.

• CPR messages (ATC correlated position report)

A CPR is a message sent at regular intervals by the ATS Providers to the CFMU. Automatic refresh is provided every minute, on average.

Each CPR is a collection of Flight Data Fields, indicating: 1. the 2D position of the aircraft (geographical coordinates), 2. the aircraft dynamic status (speed evolution, Rate of Climb, of Descent, of Turn) 3. the time on which the above information refers and 4. flight plan ID related data.

CPR data is radar derived: for example, aircraft dynamic information is obtained through the comparison of successive radar plots.

The CPR structure is represented graphically below:

Figure 4: CPR message structure

Correlated Position Report

Flight Data Fields

Time of Track Info.

Calculated Track Position

Measured Flight Level

Calculated Track Velocity

Calculated Rate of Climb

Calculated Rate of Descent

Calculated Rate of Turn

Flight Plan ID Related data

Flight Number

Airport of Departure

Airport of Arrival

EOBT

IFPLID



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• APR messages (Aircraft Operator Position report)

The APR message is a Position Report message that is sent by Aircraft Operators to the CFMU / ETFMS. Its purpose is to inform the CFMU about the progress of an airborne long haul flight, which departs outside the CFMU area of responsibility.

The APR message informs the CFMU with an accurate update of the Estimated Arrival Time or with the Actual Time Over the aircraft’s current position. It will be used to get a more accurate prediction of the sector counts.

APR messages are expected for flights that are airborne and that have departed from aerodromes outside the CFMU area and that have planned to enter the CFMU area. They are expected to be sent approximately 2 to 3 hours before the flight enters the CFMU area. This gives the CFMU sufficient time to optimise the slot allocation and to prevent overloads of airspaces where long haul flights form a significant percentage of the traffic.

Cat Data element CPR APR

ID

FPL ID data elements

(Flight number, airport of departure, airport of arrival, EOBT)

X X

ID IFPLID (System-generated ID) X X

Actual take off time X Time

Actual time of track position X X

Actual track position (2D. geographical coordinates) X X

Actual Flight Level X X

Actual ground speed X X

Position

Rates of turn, of descent, of climb X

Aircraft registration X Other

Weather condition updates X



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4 LIMITS OF EXISTING PROCESSES

This chapter describes the limits of existing ATM processes.

As mentioned in previous chapters, current ATM processes are based on the analysis of single segments of aircraft trajectories, which means that, for a given aircraft, following legs (except in certain the next one after the considered flight) are not considered as linked to previous ones.

As a consequence, there is no possibility to predict following events from the observation of on-going situations.

4.1 Introduction

With the current ATM processes, the main reasons (inter-related), which bring about a lack of prediction, could be classified as follows:

• Airline’s flight scheduling: distribution of block to block times, scheduled buffers between block to block;

• Pre-departure delays (ATM processes, before off-block);

• Prediction inaccuracy of airport turn around time estimates;

• Operational performance of the ATM processes, after off-block;

• Communication Gaps between involved actors: Airport Operator, Airline Operator, ATC, CFMU.

Figure 5: Air Traffic punctuality drivers



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4.2 Scheduling of air transport operations

The basic principles of aviation scheduling are based on:

• A post analysis of the previous season;

• An evaluation of the new airport / ATM implementation;

• A declaration of the airport capacity at an agreed quality of service level;

• The assignment of airport slots to airlines;

• Once received the slot, the elaboration of the airline schedule and the publication to passengers of the final time table.

Airline scheduling is based on previously flown block times in the same time band.

The tighter the distribution of block to block times, the smaller is usually the scheduled buffer. A small buffer between block to block, in turn, increases the risk of schedule distortion.

In particular, the problem of the low level of predictability of the airlines schedules is traduced in the fact that the pre-departure delays4 are not fully taken into account, within the airlines’ flight schedules.

In fact, looking at the following graphic (flight distribution of block times with and without pre-departure delays), it appears that due to the pre-departure delays; the curve is shifted to the right.

4 Pre-departure delays refer to reactionary delays, en-route / airport ATFM regulations and Turn around related delays (airline, airport, security, ATC, etc.)



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Figure 6: Distribution of block times with and with out pre-departure delays

4.3 Pre-departure delays

When pre-departure delays occur, the flights’ punctuality is affected. The punctuality is all the more affected that the airline’s schedule is tight (i.e. the scheduled buffer is very small) since the delay is in that case generator of knock-on effects.

A given flight could be affected by three sorts of pre-departure delays, which are:

• Reactionary delays;

• En-route / airport ATFM regulations;

• Turn around delays (airline, airport, security, ATC, etc.).

Looking at the distribution of pre-departure delays along the day in the following picture, it is possible to notice that highest primary delays are concentrated in the morning and propagate as reactionary delays throughout the operational day. En route drivers and local arrivals drivers are mainly the result of en-route and airport ATFM regulations. Local delays at the departure airport are mainly caused by turnaround issues.



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Figure 7: Distribution of pre-departure delays alon g the day

In general, the largest share of departure delay originates from operations (airline, airport, security, etc.) at the departure airport.

Turns around delays are local issues and vary significantly from airport to airport.

4.4 Prediction inaccuracy of airport turn around ti me estimates

4.4.1 Turn around times: lack of operating data

Aircraft turnaround operations refer to the preparation work of an inbound aircraft for a following outbound flight that is scheduled for the same aircraft.

Accordingly, activities of aircraft turnaround operation include both inbound and outbound exchange of passengers, crew, catering services, cargo and baggage handling. Technical activities in turning around an aircraft include fuelling, routine engineering check and cabin cleaning. Since passenger numbers and cargo / baggage loads vary from flight to flight, the realised turn around time of an aircraft is stochastic in nature. Transfer traffic may occur at airports during the aircraft turn around times such as flight / cabin crew, passengers and cargo / baggage.

Under the complex resource connection mechanism among aircraft, disruptions may occur to any processes of aircraft turn around and may consequently cause delays to departure flights. Disruptions such as connecting passengers, connecting crew, missing check-in passengers, late inbound cargo or equipment breakdown are normally seen in daily airline operations.

While disruptions caused by air transport system capacity reduction attracts much attention mostly because of its scale of impact, it is interesting to know that disruptions



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within this category account for roughly 40% ~ 50% flight delays including those caused by weather. Other delay causes (the remaining 50% ~ 60%) are contributed by the airline turn around operations in which reactionary delays may account for up to 20% ~ 30% of the 50% ~ 60% delay share, while technical faults may account for up to 10% (ref. Eurocontrol Performance Review Reports, 2004; 2005).

Delays cost money for airlines and the travelling public, no matter where the delays come from.

Punctuality data are mostly compiled from the time stamps acquired through the Aircraft Communication Addressing and Reporting System (ACARS). Time stamps may include take off time (wheel off), landing time (wheel on), arrival time (on-block at gates) and departure time (off-block at gates). However, operating data of ground handling, e.g. catering offloading start time and f inish time, are hardly recorded by airlines.

Given the crucial role played by ground operations in minimising knock-on delays in airline networks, it would be of tremendo us benefits to airline operation control, if operational data is available during gr ound operations on a real time basis. This would allow operation controllers to pa y precaution to potential events which might delay a departure and consequent ly cause delay propagation in the network.

4.4.2 Airlines’ strategy

Airframes turn around (stop) times range from twenty minutes to an hour and a half for passenger carriers. Typically turn around can be considered to cover the period from on-blocks to pushback, including disembarkation and boarding by passengers, baggage handling, refuelling and safety checks on the aircraft.

Turn around times depends on:

• Company operating strategy: some airlines plan a greater margin for turn around into their schedule that help manage the effects of delays;

• The aircraft type: bigger aircraft require longer turn around and some types are easier to load and unload by virtue of location of baggage doors on the airplane;

• Passenger connection times if the airlines operates a hub, necessitating sharp peaks in activity;

• Airport, since turn around times are often longer in international airports;

• Whether the flight is short-haul or long haul since short-haul flights are operated with higher frequency than long haul.

The impact of delays is to disrupt an airline’s planned flying schedule. In order to maximize the return on their assets airlines try to increase the proportion of time spent by flying passengers. However, this means that schedules become tighter and more prone to disruption.

Thresholds quoted for delays that disrupt the company schedule range from zero to 30 minutes. If the delay of a flight is greater than this time, the airline cannot absorb it during subsequent flight or turn around and the remaining schedule is affected (knock-



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on delays). Parameters taken into account in determining this threshold are usually the forward schedule and crew working hours, and may vary from flight to flight.

In practice airlines prefer to deal with chronic delays by accepting the disruption and continuing the schedule dealing with knock-on delays as best they can. This strategy is usually preferable to cancellation and in fact they seldom cancel because they do not want their customers to switch to a competing airline’s flight on the same route and instead prefer to fly half-empty.

However, a separate and arguably more significant form of delays arises in disruption situations such as when fog, snow or an incident such as a strike severely reduces the capacity either locally or throughout a region. When this occurs airlines are very badly affected because the disruption often catastrophically upsets the planned schedule and imposes very high costs through aircraft and crews being in the wrong locations.

On these occasions it is difficult for an airline, even with the appropriate tools, to consider different operational scenarios and their consequences in response to delay disruption. Looking more than one flight ahead is not always rewarding, as so much can happen in the meantime to make plans obsolete.

4.5 Operational performance after off-block

Delays which affect the flight after off-block are:

• Taxi time variations;

• En-route transit time variations;

• TMA transit time variations.

Variability of flight operations is a major issue for airline and airport scheduling. Arrival variability is mainly driven by departure variability; flight time and taxi-out also play a significant role.

4.6 Communication Gaps between involved actors: Air port Operator, Airline Operator, ATC, CFMU

4.6.1 ATFM current limitations

Throughout the whole process, all the involved airports actors need to share information with each other in order to carry out their own activities. The multiplicity of airport actors and the interconnected nature of air transport make this information sharing essential to the efficient and safe performance of the system. The flow of information between agents is huge and it has been well analysed in several studies and project such as Collaborative Decision Making (CDM) projects.

Although airports actors share some information, there is available information, which is not known by all actors that could benefit from it. Spatial dispersion, historical procedures, lack of incentives, etc. lead to communications gaps that may have negative effects on the efficiency of the system.



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Several recent studies have noted that currently, ATFM focus is primarily on avoiding the saturation of the air traffic control systems and is still regarded as a synonym for slot allocation mechanism. While some improvements are being developed in this sense, ATFM activities are still centred on the operational phase. In this context, it is not surprising that data processed during this phase are not consistent with data processed during the strategic and the pre-tactical phases, especially if we take into account that there are some gaps in communication between ATFM providers and other agents before the operational phase.

The lack of direct communication between airport coordinators and ATFM Providers may in particular result in inconsistencies between airport slots and ATFM capacity.

4.6.2 ATFCM evolution

One of the cornerstones of the ATFM evolution processes is the improvement of collaboration between the CFMU and the ATM partners, focusing mainly on the sharing of accurate ATM data (FPL, Airspace, crisis decision, etc) within a regulatory framework between all stakeholders. Through an increased collaboration, it is expected that the ATFM will evolve to the ATFCM – Air Traffic Flow and Capacity management – which consists of ensuring seamless and continuous Flow and Capacity Management operations from strategic planning to tactical usage without considering fixed timeframes.

In ATFCM, the Strategic, Pre-tactical and Tactical phases will be continuously iterative and interactive. The output of a phase will aim at preparing the next phase and will therefore be used as input element to be considered at the beginning of the next activity together with any feedback (Figure 8).

Strategic Flow & Capacity Planning

Optimised Capacity Management

Tactical Flow &Capacity Management

Harmonised Planningconsidering :

- Traffic Demand

- Airspace Structure

- ATC Capabilities

- Airport Capabilities

Optimised Daily Planand

anticipation of eventsin order to maintain

the network stability.Reaction to real-time

events to minimisedisruptions impact

and/or to take benefitof opportunities.

1 year 1 week real-time

Planning

Execution

Real-TimeOperations

- ATC

- ASM

- Airport

- AOs

Resources

- Airspace

- ATC

- Airport

Feedback

Feedback Feedback Feedback

TrafficForecast

Figure 8: Seamless and Continuous ATFCM Process



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The ATFCM Evolution Plan develops a series of requirements intended to improve the communication between the CFMU and the aircraft operators, other airspace users (in particular, militaries), airport co-ordinators, airports managers and other involved agents. In this sense, establishing permanent links between the CFMU and the operational centres of certain aircraft operators would allow to improve CFMU visibility of the network and thus, enhance the ATFM slot allocation efficiency.

4.6.3 CDM studies

CDM studies have concluded that communication between airports actors could be improved significantly, particularly during the operational phase: a study carried out at Barcelona’s Airport “showed, in terms of exchange of information between the main business processes within the airport, ATC and the airlines / handlers that the exchange between FMP, ATC and the CFMU is considered to be acceptable, whereas the exchange between airlines / handlers and ATC, FMP is unsatisfactory. Also the exchange between airlines / handlers and airport operations is insufficient. This leads to sub-optimum decisions with regard to the management of ATC and airport resources such as runway and taxiways, stands and gates. In addition it is likely that CFMU and Airport Co-ordinated Slot adherence to ATFM restrictions will be compromised.”5

Airport CDM projects have identified several communication gaps, which may result in inconsistencies between airport slots, FPL and ATFM slots consistency. The most significant ones are the following:

• Aircraft operators do not always share with other airports actors (airport operations, CFMU, ATS, ground handlers, etc.) relevant information concerning the evolution of flights, which could help to reduce delays and improve demand management. In particular, airlines do not share information concerning inbound flights, which can be significant for subsequent outbound flights. For example, if the arriving flight takes off in the precedent airport with a 60 minutes delay, the turn around process and the departure time will also be delayed. This information is known by airlines, but in most cases it is not shared with other partners. This communication gap may result in wasted capacity (the unused departure slot is lost) and in additional delays;

• At airports, there is available information that could be used to calculate more accurate taxi times and which is not used. Today taxi times are considered as fixed values (default taxi times) not only in the CFMU system but also at local airports for the flight progress calculation. At certain airports (i.e. Brussels, Roissy CDG, etc.) taxi times present significant variability and considering fixed values may introduce important mistakes in the flight progress calculation;

• Local ATC and CFMU cannot take into account aircraft operators’ preferences and airport operations constraints in the departure sequence. Presently and as a common rule, aerodrome ATC takes into account several principles in departure sequencing (“first come first served”, aircraft spacing, taxiing routes, choice of

5 Eurocontrol. Airport CDM Applications Operational Concept Document. December 2002.



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SID, etc.) It is possible that these set of rules may not correspond to an optimised departure sequence;

• There is no systematic way of disseminating information concerning the disruption of the normal capacity levels at an airport. The information is provided ad hoc (usually by telephone) and CFMU applies the regulation on restricted airport capacity, as well as a special start up request process, only after the situation has been aggravated due to aircraft holding or diverting to other airports.

In order to address these problems, six CDM applications have been developed: the “Airport CDM Information Sharing”, the “CDM Turn around Process”, the “Variable Taxi Time Calculation”, the “Collaborative Pre-departure Sequence”, the “Management of Updates in the Turn around Process” and the “Reduced Airport Capacity Management due to Disruption”. All these applications could have a positive effect on the improvement of the flight’s predictability.

4.7 Conclusion

Ultimately, improving punctuality means identifying sources of variability that can be reduced, reducing the variability of flight phases below given values, and being able to predict given values during the scheduling phases.

Punctuality is the “end product” of a complex interrelated chain of operational and strategic processes carried out by different stakeholders during different time phases and at different levels (local/network) up to the day of operations.

Punctuality is affected by the lack of predictability of operations in the scheduling phases and by the variability of operational performance on the actual day.

Part of the unpredictability of actual situations with respect to scheduled ones, derives from the lack of information about the status of the flight during the different phases of the day.

Since nowadays each single flight segment is separated from the previous and following ones, there is no possibility to predict in advance consequences which affect subsequent flights.

The aim of the ABCD (Aircraft-Based Concept Develop ment) consists in using the aircraft registration, which is already a param eter of the FPL message, in order to link the separated flight segments. Thank to this linkage, it will probably be possible to update in a more efficient way the p redictions and thus to provide a better picture of the future traffic flow over th e European sky.

In particular, as the CDM processes will allow an improvement regarding the sharing of all the relevant information between the parties involved and as they support a permanent dialogue between the partners through all phases of flight, it could be said that the ABCD concept fits into the CDM processes development.



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5 ABCD CONCEPT DESCRIPTION

This section is dedicated to the description of the ABCD concept.

The development of the concept is on its way and will be developed further, during the second part of the study: Work Package 2.

As an introduction to the future work, this document presents the main assumptions and principles underlying the ABCD mode of operations, the description of the expected environment for its deployment, the overall view of the ABCD services and the description of some of the key information messages used or required by the ABCD concept.

5.1 Introduction

Aircraft-Based Concept Developments (ABCD) explores the reorganisation of the flight plan management into a re-named “aircraft-based” management.

ABCD is primarily based on the use of aircraft parameters, in order to establish a link between the individual flight plans of the CFMU database. This aspect intends to constitute a true evolutionary step forward in the improvement of predictability, and efficiency of the ATM operations.

Thanks to the linkage of individual flight plans, it should be possible to provide more accurate predictions of the downstream legs of an aircraft itinerary, in particular when a flight suffers from perturbations (e.g. delays). Such accurate predictions are expected to lead to an optimised ATFM slot allocation, by e.g. allocating more efficiently the ATFM slots on an early up-to-date knowledge of the flight progress.

• Reorganisation of the flight plan management

The acronym “ABCD” – Aircraft-Based is introduced in order to highlight the fact that the use of the aircraft registration, now offers an additional process to manage the flight database. Nowadays, the airlines can already transmit such information, via the RPL and FPL. In the context of ABCD, the airlines could eagerly transmit the information so long as they get the benefit from it (better use of available capacity, increased impartiality in the slot allocation process, enhanced planning of resources).

The ABCD “strategy” also states that the transmission of the aircraft registration information – together with the turn around minimum duration (TTM) – should be organised in such a way, that airlines keep flexibility to adjust their operations at the airports, as they do it today.

Flexibility is indeed a key aspect for many airlines, which need to be able to change the aircraft allocation to flights in function of commercial and/or technical constraints. In the context of ABCD, the possibility of notifying a change of the allocated aircraft will be made available, through the use of the existing communication channels, as for example the CHG (Change) message, for transmission of the modifications to the flight plans.



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• ATM & CDM environment

The ABCD concept development will not necessitate any changes in the ATM (ATC, ATFM, airports) current equipments or procedures. All the current messages, which are described in § 3, will be used in the frame of the concept.

In particular, as the CDM processes will allow the sharing of all the relevant information between the parties involved and as they support a permanent dialogue between the partners through all phases of flight, it could be said that the ABCD concept fits into the CDM processes development.

The ABCD concept will output new procedures for exchanging information about the aircraft. The messages could be used by the other CDM procedures currently under implementation or development. In return, all the information exchanges in the frame of CDM will be integrated into the ABCD concept, for a better flight plan management.

In the ABCD concept, the emphasis is put on the use of the existing communication channels between the airline and CFMU (exchange of flight plan messages in the current framework of submission, changes and cancellation of flight plans).

ABCD would therefore act as a complementary CDM enabler to other CDM existing at some airports. For example, some airports are implementing the DPIs and FUM processes, which will provide CFMU with the most accurate predictions of the turn around progress at the airports and of the take-off times. For these airports, the ABCD concept should be seen as part of a CDM integrated system. ABCD would provide more accurate data on more than one stage ahead (e.g. the next leg to the next leg of an aircraft’s itinerary).

On the other hand, the ABCD concept could be seen as a new basic CDM process at the airports where the implementation of the other CDM processes have not yet been implemented.

5.2 ABCD environment definition

The purpose of this section is to describe additional or specific constrains that the ABCD concept deployment imply on the ATM processes environment, compared with the current environment, that is described within the previous sections (Flight Plan database, roles and technical aspects).

5.2.1 CFMU Flight Plan database

Nowadays, the management of the CFMU Flight Plan database is supported by a continuous process that collects information on flights / schedules demand all over the entire planning from the strategic phase, through the collection of the RPLs (Repetitive Flight Plans), down to the tactical phase, through the collection of the FPLs and modification to the flight plans.

The flight demand is initially based on historical data and statistics and is refined as long as information of airspace usage – e.g. the RPLs first and then the FPLs and modification to the flight plans – becomes more accurate.



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At a pre-tactical level, one day before the day of operations, the flight demand forecast would turn into an aircraft demand forecast, by taking into account the aircraft allocation schedule for different flight plans (aircraft registration associated to the different legs of an aircraft’s itinerary during the day). At this stage, the link between the individual flight plans is established. If the aircraft allocation schedule is not made available by airlines, then, the link between individual flight plans will not be considered and the demand forecast will be treated as it is today.

The linkage between individual flight plans will constitute the aircraft demand profiles within the database. After that, as soon as up-to-date information, like a delay on a portion of the aircraft’s itinerary (i.e. on a flight), is made available, the aircraft profiles are re-computed accordingly. For example, in case of a delay that occurs on a flight for which the stop time cannot absorb the turn around minimum time (TTM) plus the delay, the downstream legs of the aircraft’s itinerary will be updated.

It must be noted that the ABCD concept of operations is flexibly applied depending on the available information coming from the airlines. That is the reason why the database should maintain flight demand profiles, as it is today together with aircraft demand profiles, whenever airlines can provide the aircraft registration. As an example, among the airlines interviewed, four airlines out of five were feeling disposed at providing the aircraft registration information in advance, one day before the operations.

At the level of tactical phase (i.e. during the day of operations and until a few moments before the off-block-time), airlines could keep on notifying any modifications to the aircraft allocation schedule by exchanging messages with CFMU, as they do today when they send CHG messages for updating the fields of the RPL or FPL.

In essence, with ABCD, the management of the flight plan database is supported by a linkage of the different flight plans, which provides automatic update of the downstream flight plans, when a modification of a given flight plan occurs, to ensure more predictable and consistent Flight Plan data within the database.

5.2.2 Roles and responsibility

• CFMU

The CFMU is the central unit that collects and broadcasts flight data information. In its role of central processor of the information, it is well positioned to make the linkage between various elements describing the course of an aircraft’s itinerary i.e. between different flight plans. If a modification to an initial flight plan occurs, the CFMU should be able, when it has the necessary information (aircraft registration and turn around duration), to update the downstream flight plans.

The CFMU should optimise the slot allocation system by considering the whole journey of an aircraft, when the linkage of the flight plans is effective. If a delay resulting from the allocation of a slot to a given flight propagates, the system should update the



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subsequent times of the aircraft journey, including estimated take off and landing times of subsequent flights.

The CFMU should be able to process TTM information received from the airlines (minimum turn around times). In order to ensure consistency with operations, the airlines should communicate TTMs for their different aircraft types. This could be done strategically (e.g. at a time the airlines define their commercial schedules and/or send RPLs), with regular co-ordination for updates.

The CFMU could be given a primary role in flight data consistency management, as a central repository for relevant data updates, by transmitting accurate flight data to all interested actors. For instance, when a delay propagates to the next stages of the aircraft’ journey, the CFMU, could made this information available to the involved airlines, airports’ actors and ANSPs.

• Airlines

The airlines are responsible for the provision of their flight intentions to CFMU, in the form of RPLs, strategically, and/or in the form of FPLs & flight plan updates, at a pre-tactical level.

Considering that every airline has to define an aircraft allocation schedule in advance (generally they finalise the schedule during the day before the day of operations), the schedule could be made available to CFMU pre-tactically. As the airlines already send a message to the different operating agents at the airports, they could include the CFMU as an additional recipient of the distribution list.

The aircraft allocation notification should remain flexible enough in case of ad-hoc events, where the airline can decide to modify the aircraft allocated to the flights. In such cases, they transmit the update to CFMU, via a CHG message.

The airlines should transmit TTMs (minimum duration time required for turn around operations at an airport and for a given aircraft type). Typically, TTMs can range from twenty minutes to an hour and a half, for major airports.

In case of changes of the TTM parameters, the airlines should notify those changes to CFMU.

• Airport – ground handlers

Airlines’ agents or ground handlers are the representatives of airlines at the airport of operations. Each agent (or handler to which the task is sub-contracted) covers turn around activities, including disembarkation and boarding of the passengers, baggage handling, refuelling, safety checks on aircraft, etc.

The impact of delays is to disrupt an airline’s planned flying schedule. The airlines’ agent at the airports monitors the progress of the turn around progress. They notify the airlines’ headquarters of the actual off-block and take off times of the aircraft, via dedicated messages.



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When the aircraft has taken-off, airlines’ headquarters are informed on the actual take-off time of the aircraft, via dedicated messages. Some of these messages can be sent by an airlines’ agent (e.g. case of a MVT message). Others are sent by ANSPs (e.g. case of a DEP message).

Therefore, airlines’ agents could inform CFMU about the actual take off time of the aircraft by including the CFMU into the recipient list of messages (e.g. MVT message).

Then, CFMU could have other sources of up-to-date information, in addition to the messages they receive from ANSPs (such as DEPs).

• ANSPs

The ANSP is responsible for providing actual (real-time) position reports to the CFMU (radar data derived), in order for the CFMU to verify whether the aircraft progresses according to plan. If the aircraft observes deviation, the CFMU should calculate the impact on the entire downstream aircraft profile (i.e. linked flight plans).



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5.3 ABCD operating concept principles

The principles of the ABCD concept are described through real cases of aircraft operations. These were selected according to the interviews held with the airlines. These interviews provided for a set of regular cases, where the operations are frequently impacted by the knock-on effects of delays due to a single perturbation (e.g. ATFM slot), occurring at a given station of the aircraft’s itinerary during the day.

The first example is an aircraft operating routes between Lyon and Zurich airports, eight times a day. In this case, an aircraft is allocated to four flights from Lyon to Zurich airports and to four flights from Zurich to Lyon airports. An ATFM regulation was implemented during the afternoon, to protect an en-route sector. The regulation has impacted a set of flights, during the afternoon, by the allocation of a single slot at one of the airports. Delays have been propagated.

The second example provides a case of operations involving more than two airports: Rennes, Paris CDG and Southampton. A single aircraft is allocated to a set of eight successive flights, starting early in the morning, at Rennes airport, going to Paris CDG airport, and to Southampton. Then, the aircraft returns to Paris, and arrives finally at Rennes during the end of the morning phase. The same itinerary is repeated during the afternoon. The analysis of this example will show how a delay occurring at a given airport can impact the operations of several flights ahead and how the implementation of an ABCD concept could improve the management of delays.



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5.3.1 Case of operations: flights between Lyon and Zurich airports

Figure 9: Lyon – Zurich flights (return)

Airport: Lyon

Flight: AFR3477 Aircraft: ATR 42 A/C Registration: F-GPYM Initial in-block time: 17:15 Regulated in-block time: 18:08 Actual in-block time: 18:02

Flight: AFR3478 Aircraft: ATR 42 A/C Registration: F-GPYM Initial EOBT: 17:45 Regulated EOBT: 18:16 Actual EOBT: 18:44

Turn around process Aircraft: ATR 42 A/C Registration: F-GPYM Initial Stop Time: 30’ Minimal Turn around time: 30’ Actual Stop Time: 42’

Flight: AFR3477 Aircraft: ATR 42 A/C Registration: F-GPYM Initial EOBT: 16:05 Regulated EOBT: 17:01 Actual EOBT: 17:00

Airport: Zurich

Flight time: 1:10

Flight: AFR3478 Aircraft: ATR 42 A/C Registration: F-GPYM Initial in-block time: 18:55 Regulated in-block time: 19:26 Actual in-block time: 19:49

Airport: Zurich

Flight time: 1:10

CFMU: Slot allocation list

Flight Initial Time Over reference point

Regulated Time Over TV ref. point

AFR3478

KLM1230

DLH910

19:30

19:30

19:30

20:01

20:03

20:05

Actual Time over

(AFR3478):

20:32



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The first case of operations is an example of an aircraft going from Zurich to Lyon, staying at Lyon during a limited time, and returning to Zurich. The example is a real case of operations, extracted from the flight plan repository database (ARCH) of the CFMU. It is presented here as an illustration of the ABCD principles.

The aircraft type is an ATR 42, registered with the registration “F-GPYM”. The example focuses on two successive flights, to which the aircraft was allocated: 1. Zurich – Lyon; 2. Lyon – Zurich.

Both flights are subject to the same ATFM regulation, issued to protect an en route sector (LSAGSE2, in Switzerland), from over-delivery. The regulation is associated to a slot allocation list. The flow rate requested for the regulation is 30, i.e. there are 30 slots allocated within the hour (one aircraft entering the sector every 2 minutes, in average).

The Zurich – Lyon flight is identified as AFR 3477. This flight was initially scheduled at 16:05 for departure (off-block), but because of the ATFM regulation, the departure has been delayed to 17:01. In reality, the aircraft has left the stand at 17:00.

Because of the allocated delay, the next flight of the aircraft’s itinerary (AFR 3478) is unable to meet its schedule. In addition, the same regulation applies on this flight, so that the initial scheduled off-block time (17:45) was delayed to 18:16. However, such an allocation has been based on individual flight plans not linked together, thus generating an inconsistency: the AFR 3478 cannot comply with a departure at 18:1 6 allocated slot because of the initial delay allocat ed on the AFR 3477 flight.

Indeed, in the present example:

• The stop time, i.e. the scheduled time allocated by the airline for turn around, is very short (30’). It is equal to the minimum time window necessary for the activities of handling, boarding and deplaning of passenger, refuelling for an ATR 42 aircraft. Therefore, a delay occurring during the course of the AFR 3477 flight will be propagated to the next AFR 3478 flight;

• The actual records show that the AFR 3478 flight was effectively unable to respect the slot allocated on the basis of the initial flight plan: 18:16. The actual time of departure was 18:44;

• The airport operations were impacted. For example, the aircraft lasted at the airport for 44 minutes, above the 30 minutes turn around time window. This could be a consequence of the disruption of the turn around schedules: for example, stand availability, etc;

• The ATFM slot allocation process is impacted by the fact that the two flights AFR 3477 and AFR 3478 are not linked together (see figure 9). The slot allocated to the AFR 3478 flight (corresponding to a regulated time over TV entry point of 20:01), can not be met because of the regulation applied on the previous AFR 3477 flight. The economic consequence of an “unused” slot is significant as it is detailed below.



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In an “ABCD” context, the following would have happened:

• Slot allocation mechanism improvement:

o The airline would have sent its aircraft allocation schedule the day before the day of operations to CFMU, by including the CFMU into the recipients list (including airlines’ agents, handlers and other involved actors at the airports of operations);

o The airline would have submit a RPL or a FPL strategically or pre-tactically to CFMU;

o The CFMU system knows that the aircraft will stop at least 30 minutes at Lyon airport and can therefore evaluate the delay propagation effect for the next legs of a delay occurring on the first leg; at Zurich airport (thanks to the linkages of the FPLs, see below);

o The CFMU would have linked the two RPLs or FPLs corresponding to the AFR 3477 and AFR 3478 flights, by using the aircraft registration: F-GPYM;

o Within the CFMU FPL database, AFR 3478 flight profile would be updated according to the up-to-date information that concerns the previous AFR 3477 flight. This would optimise the overall slot allocation process, including the improvement of the slots allocated to the other airlines;

o Because of the linkage of the FPLs, the system knows that AFR 3478 is unable to comply with a slot allocated on the basis of an individual flight plan (20:01). This is detected, in advance, pre-tactically, thus contributing to the optimisation of the process. In the example, the “20:01” slot can be allocated to another flight, DLH910, which hence benefits from an improved slot. In turns, this could free a slot for the next KLM1230 flight;

o Then, the overall delay generated by this very regulation is reduced.

Note:

Without ABCD, the above analysis shows that a slot would have been lost (the slot corresponding to 20:01). A preliminary cost benefit analysis, presented in the § 6 of this document shows that the economic saving resulting from the slot recuperation worth nearly 2600 Euros.

• Flight data consistency: availability of on-line information about aircraft status:

o The system processes up-to-date information, from the messages issued from ANSPs: DEP and CPRs;

o As soon as the aircraft takes off (AFR 3477 flight), the system has the confirmation of the real delay of the aircraft (via DEP or MVT messages). In the example above, the actual time for departure is 17:00;



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o The system re-calculates the times at Lyon airport according to the latest information about AFR 3477 flight. It provides more accurate estimates of the in-block AFR 3477 time and accurate estimates of the EOBT corresponding to the next flight (AFR 3478);

o The updates are transmitted to all interested actors, at the airport of Lyon, who thus benefit from more accurate and consistent information.

o The updates are transmitted to more than one stage ahead, if applicable.

Note: In the example above, accurate information could be provided as soon as the aircraft takes off from Zurich, i.e. about 70 minutes in advance for the turn around operations at Lyon. Update information on the schedule to the following stage, would thus be available 70 + 30 minutes = 100 minutes for the next stage, and so on.



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5.3.2 Case of operations: flights between Rennes, P aris CDG and Southampton

Figure 12: Rennes – Paris CDG – Southampton flights

The second case of operations is an example of an aircraft going from Rennes to Paris CDG, and then to Southampton, returning to Paris CDG, and Rennes, during the morning. The same itinerary is followed during the afternoon. In total, eight successive flights are allocated the same aircraft. The example is a real case of operations, extracted from the flight plan repository database (ARCH) of the CFMU. It is presented here as an illustration of the ABCD principles.

The aircraft type is an ATR 72, registered with the registration “F-GVZL”.

In the figure above, the initial times of departure (EOBT) and in-block are shown for the different legs of the aircraft’s itinerary: These are the scheduled times of departure and arrival, by the airline. Rennes is the first airport of departure, Paris CDG is the first airport of arrival and second airport of departure, Southampton is the second airport of arrival and third airport of departure, etc. The airline’s scheduled turn around duration times (stop times) are indicated for each airport.



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The airports, for which turn around duration times (stop times) are equal or very close to the minimum (35’ and 30’) are highlighted in red. Those airports are the ones, likely to be impacted by delay knock-on effects.

Indeed, in the present example:

• For the first morning flights, turn around times (stop times) at Paris CDG (second airport of the day) and Southampton (third airport of the day) airports are very short (equal to the minimum): 35’ at Paris CDG and 30’ at Southampton. These leave no flexibility to absorb a delay since these times correspond to the minimum duration times for turn around at these airports. Therefore, a delay occurring at the first airport, Rennes, even being low, will be propagated to the next flights;

• The delay can be recovered at the fourth airport of the day, Paris CDG, where the (stop time) duration time is set at 120 minutes. Then, if the cumulated delay inherent to the third flight of arrival (Southampton – CDG) is lower than 85 minutes (as the minimum turn around duration time for CDG is 35 minutes), the delay could – in principle – be fully recovered;

• Another chance for delay recovery is offered at the fifth airport of the day, Rennes, since the time for turn around duration (stop time) is 50 minutes, i.e. 20 minutes above the minimum;

• For the afternoon flights, turn around times (stop times) at CDG and Southampton are – as for the first morning flights – equal to the minimum. Then any delay occurring on the sixth or seventh flight will certainly propagate downstream.

With the above analysis of the aircraft flights schedule during the day, the benefits of linking flights are made clear:

• Because of the linkage of the FPLs, the actors can estimate the delay resulting from perturbations occurring at several stages upstream. For example, in the morning, any delay occurring during the first legs of the aircraft itinerary, has an impact on next in-block and off-block estimated times. This happens, at least at all stages, until a “delay recovery” is possible (fourth and fifth airports);

• The system automatically recalculates time estimates, without manual intervention of the actors. Updates are transmitted to all interested actors, one to several stages ahead, who thus benefit in advance, from more accurate and consistent information;

• In case of ATFM regulation, the system will be able to optimise the process of slot allocation by linking the ATFM slot, with the knock-on effects generated downstream.



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5.4 ABCD information messages

This section describes an overview of the expected information messages used or required by the ABCD concept.

Individual fields of data contained within these messages are expected to be interpreted, processed, and stored automatically to increase the predictability of the flight plan database. Thanks to the linkage of flight plans, the accuracy of the future flight estimates (several flight stages ahead) will be improved.

5.4.1 Airlines – data exchanges with the CFMU

• Minimum Times for Turn around (TTMs):

For each airport of operations and for their different aircraft types, the airlines can transmit their minimum Times for Turn around to CFMU. The information will be used by CFMU to re-calculate the estimates of future flight plans (several stages ahead, if applicable) when an actual delay is detected on a flight and when the delay cannot be absorbed during turn around(s).

Minimum Times for Turn around (TTMs), can be communicated strategically to the CFMU, once commercial schedules are established for a given winter or summer season.

• Aircraft allocation schedule:

An aircraft allocation schedule (aircraft registrations allocated to flight) is transmitted to CFMU by the airlines, in the form of an electronic message. The information will be used by CFMU to link Flight Plans of the database. Thanks to this linkage, the CFMU will be able to re-calculate the estimates of future flight plans (several stages ahead, if applicable), when an actual delay is detected on a flight and when the delay cannot be absorbed during the stops times.

Aircraft allocation schedule are communicated to the CFMU the day before the day of operations.

In case of changes, during the day of operations, the airlines transmit the new aircraft registration, in the form of a CHG (Change) message.

A typical aircraft allocation message transmitted to CFMU could be like the following message, which is an example of internal message exchanges between airlines’ agents:



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Figure 13: Aircraft allocation message

5.4.2 Airlines’ agents (airport) / ANSPs – “DEP” or “MVT” messages

A “DEP” or a “MVT” message is expected to be transmitted to CFMU either via ANSP – CFMU existing communication channels (DEP message) or using the existing communication channels defined internally between the actors at the airport of operations and the airline Operational Control Centre (MVT message).

A DEP or MVT message is transmitted to the CFMU at aircraft’s take off. It contains information about the actual off-block time, take-off time, and up-to-date arrival estimates (in-block times), for the flight.

A typical MVT message transmitted to CFMU could be like the following message, which is an example of internal message exchanges between airlines’ agents:

Figure 14: MVT message



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5.4.3 ANSPs – flight progress messages and actual p osition reports

The exiting messages and actual position reports remain the same as today’s ATM operations. They are automatically transmitted to the CFMU to maintain the flight plan database up-to-date.

The estimates obtained through the linkage of the flight plans, are confirmed or refined with the existing flight progress messages and actual position reports.

5.4.4 DPIs / FUMs / CDM messages

If an airport is equipped with “CDM” – DPI / FUM processes, CFMU can use the CDM messages to evaluate the next aircraft leg in the database, with higher accuracy.

DPIs are sent by the airport’s actors. FUM is a message sent by the CFMU to the airport / airline. .

When a resynchronisation for the next legs is waiting the CFMU send an error message to the airline for correction.

5.4.5 CFMU information broadcast

In order to inform “others” (airlines, airport’s actors) about the future flights prediction updates, a set of messages are expected to be transmitted by CFMU.

The messages will contain time estimates (departure, arrival) for the aircraft at different anticipation levels: one to several stages ahead, if applicable. Then, they should complete the estimates provided by the FUM (Flight Update Message) at the airports whit DPI / FUM messages, by providing estimates “more than one stage ahead”. At the airports without DPI / FUM messages, they will enhance the predictability of both the next flight and subsequent future flights.

These messages will be sent at significant updates of the flight plans in the CFMU flight plan database: at process of a DEP / MVT, at important changes (to be defined precisely) of the aircraft’ itinerary.



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6 ABCD COST BENEFIT ANALYSIS: OVERVIEW

6.1 Introduction

This chapter intends to present a high level CBA (Cost benefit Analysis) of the ABCD concept in order to provide a broad estimation of the advantages and drawback conveyed by this concept. A more detailed CBA will be developed in further development of the study.

ABCD concept aims at linking individual flight plans with the support of the aircraft registration and at updating aircraft associated flight plan parameters according to the aircraft information status. Thanks to the ABCD concept, real-time on-line information about aircraft status could also be provided to all involved airport stakeholders improving airport related activities and slot allocation mechanism.

In the case of the ABCD concept, costs are associated to the development and the implementation of this new concept for airports, airlines and CFMU systems and to the creation and implementation of new procedures.

On the other hand, benefits will probably come from the improved availability of real-time on-line information about the aircraft status, the automatic updating of future flight plans and consequently from the possibility for all airport actors to better anticipate potential flight disruption and thus take better real time decisions and actions to smooth the effect of the disruption.

The CBA focuses on the main ABCD fundaments which can be summarised as:

• On-line information management. It means that airport actors manage same on-line information which is used to improve prediction capabilities especially for the CFMU, and slot assignment process, which result in a better use of airports and airspace actors’ resources;

• Reduction of reactionary delays and reduction of propagation effects. It means that considering Air Transport as a chain and not as single separated sequence of flights, it is possible to better predict effects on subsequent segments due to previous segments of the entire aircraft itinerary;

• Reduction of the airlines personnel in charge of reallocation of flight plan slots, who no longer have to allocate personnel for renegotiation of ATFM slots, or for the communication of delays as ABCD can provide automatic updates of flight plans.

6.2 Primary Delay and Reactionary Delay

Delays can occur during the different phases of a flight: when the aircraft is airborne, taxing or parked on the apron. For operated flight versus schedule, one also has to consider another delay type breakdown. Weather delays are primary delays (airborne/ground) or reactionary delays (departure/arrival).



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Primary delays correspond to initial delays caused to a given flight. They are classified according to the delay causes: passenger and baggage, cargo and mail, aircraft and ramp handling, technical and aircraft equipment, damage to aircraft, flight operations and crewing, weather, airport and governmental authorities (including ATC). Late arrivals of connecting flights, connecting passengers, bag gages, loads, or crew members, are not been included in primary delay causes.

Reactionary delays correspond to delays due to the late arrival of aircraft delayed during its previous leg operation, late arrival of a connecting flight, passengers or load, and late arrivals of crew members, expected from another flight.

Reactionary delays occur following primary delays, and if the latter would be reduced, the former would also diminish consequently. Initial (primary) delay could indeed cause disturbances along the day, due to rather tight normal operating schedules, established to achieve economic efficiency, resulting in reactionary delays.

Airlines are in some cases willing to take extreme operational measures in order to avoid, or minimize the impact of reactionary delays (like cancelling one or more waves in case of severe hub operation disturbance).

For a thorough cost assessment of a flight-by flight basis, measuring delay is a difficult matter, since they have to be broken down according to the above mentioned classification and would require very detailed delay statistics identifying for each flight:

• Origin and destination;

• Original schedule;

• Actual time for each phase of flight (parking, taxiing towards take-off, airborne, and taxiing after touch down);

• Name of operating airline and;

• Aircraft type.

The different elements which constitute the various types of delays are:

Figure 15: Types of delays

The figure compares the flight schedule and actual flight, and shows how a delay in the different phases (departure, taxi-out, airborne, taxi-in) affects arrival punctuality. Published airline schedules generally incorporate a buffer, which is added to the

Off-block

Buffer

In-blockLandingTake-Off

Flight Schedule

Actual Flight

DepartureDelay

Taxi-outDelay

Taxi-inDelay

AirborneDelay

ArrivalDelay

Off-block

Buffer

In-blockLandingTake-Off

Flight Schedule

Actual Flight

DepartureDelay

Taxi-outDelay

Taxi-inDelay

AirborneDelay

ArrivalDelay



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planned flight plan, in order to accommodate statistically foreseeable delays. When accumulated delays exceed the buffer, delays occur. Delays and buffer are linked by the following formula:

Arrival delay = departure delay + taxi-out delay + airborne delay + taxi-in delay – buffer

Primary and reactionary delays do not have the same impact on costs, as illustrated in the following table:

Scheduled Flights Distribution

Primary Delays 60%

Reactionary Delays 40%

Table 2: Delays distribution 6

Who benefits from ABCD?

All involved airport actors will benefit from ABCD concept implementation:

• Airport Operator will be able to improve service provision to their customers through better allocation resources as they could be informed long in advance of the future potential disruption in term of flight plan schedule consistency. These apply to both the tactical level, through stability in gate and stand allocation, as well as strategically, as better use of infrastructures supports greater passenger throughput. Airports should also be able to provide better information to their customers. Overall, the airport quality of service should be enhanced;

• As ABCD should help to control reactionary delays, improving the predictability of aircraft operations, aircraft operator will be able to reduce the tactical and strategic cost of delays;

• Ground Handler will be able to improve the use of their resources, saving costs and providing an improved level of service;

• ATC / CFMU will benefit at both local and network level. ABCD will provide a better picture of future traffic flows, improving its management through better expectation of the future ATFM regulations, and better slot management (reduction of unused ATFM slots). In the long term Air Traffic Control Centre will improve the balance between their resources allocation and their capacity per rapport to the traffic demand as a consequence of the increased confidence in the predictability of traffic flows.

6 Reference: Airport CDM Cost Benefit Analysis, EEC note N.18/05, 2005



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Table 3: ABCD Benefits

6.3 Costs of implementing ABCD concept

Costs are very sensitive to the airport type, dimensions and complexity. ABCD concept, as previously mentioned, can be seen as a new information system for airports where CDM is not implemented, and as one more source of information for the CDM integrated system for those airports where CDM are or will be implemented in the future.

As a general guideline for costs, it is possible to indicate some categories of costs like:

o Project definition and management: concerning the project definition, costs are associated to people dedicated to understand the problem, introduce the new concept and its applications. Concerning the project management, costs are associated to the analysis of on-line information, to the reporting and communication to the dedicated staff;

o Procedures development: costs associated to the procedure development are those related to the circulars, handbooks and internal procedures to be defined in correspondence with the introduction of the new concept.

o Training: costs associated to the training of staff people who will deal with the new system.

o System integration: these costs include the modification to the airport actual information system in the way of software development. As above mentioned, the integration has to take CDM implementation into account;

o Hardware: this category includes new hardware to implement ABCD system.

Aircraft Registration Number

Link

• Reactionary Delays reduction

• Optimize use of Infrastructures

and Resources

• Unused Slot reduction

• Down-line effect reduction

On-Line Information on Aircraft Status

• Optimize use of

available Capacity

Performance

MeasurementPerformance DriverStrategic Objective

Aircraft Registration Number

Link

• Reactionary Delays reduction

• Optimize use of Infrastructures

and Resources

• Unused Slot reduction

• Down-line effect reduction

On-Line Information on Aircraft Status

• Optimize use of

available Capacity

Performance

MeasurementPerformance DriverStrategic Objective



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6.4 ABCD Benefits and their estimation

ABCD benefits are described below, and they all derive from the improved information availability provided by the link created between currently separated flights. The possibility to track the itinerary of each aircraft generates benefit for all airport actors.

6.4.1 Slot Allocation mechanism improvement

EEC Analysis of Unused ATFM slots7 (2000) provides conclusions about the impact of unused slots on the total delay. Taking into account the definition of “unused slots” as empty spaces in sequence of slots in regulations, which could be used by a flight, recovery unused slots which represent the 3.6% on average, would make the total delay 21% lower than what it could be if all information concerning potential slot recovery were known as soon as possible.

Moreover, traffic smoothing is improved if the operational disturbances are transmitted to the ETFMS / CASA system as soon as possible. This shows the interest in having a closer look at the importance if transparent information flows in the efficiency of the system.

Using ITA (Institut du Transport Aérien) study8 it is possible to evaluate the economic saving deriving from the reduction in delay associated to the decrease in the number of lost slots.

Starting from the consideration that every lost slot contributes around 36 minutes of additional delay to the total delay on average, multiplying the number of recuperated lost slot, it is possible to calculate the number of saved minutes of delay.

N. of saved minutes of delay = 36 min x N. Of recuperated lost slots

The most comprehensive report on the cost of delays in the air traffic management system is the University of Westminster Report9. In the report, one specific value (72 euros per minute) was presented as a typical average value. This value is only valid for specific circumstances, since it is a tactical ground cost, with the network effect (including reactionary costs) and also includes the opportunity cost to an airline of lost passengers.

Using the data corresponding to the Air Delay Cost, which is 72 euros/minute, the economic saving due to ABCD implementation system can be calculated as:

Economic saving = N. of recuperated lost slot x 36 x 72

7 Reference: Analysis of Unused ATFM slots, EEC note N.9/2000, June 2000 8 Reference: Costs of Air Transport delays, report from the Institut du Transport Aérien, November 2000 9 Reference: Evaluation of the true cost of airlines of one minute of airborne or ground delay, report commissioned by the Performance Review Commission, University of Westminster, May 2004



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6.4.2 Enhanced planning of Airport and Ground Handl ing resources with respect to flight schedules

Thanks to the availability of on-line information about aircraft status there will be an improvement in the alignment between scheduled and actual use of airport resources.

6.4.3 Improved Cost efficiency for Ground Handlers

Ground handlers could use a more accurate estimate of landing time, several stages ahead of the actual flight. By acting – in advance – on the more accurate information, ground handlers can optimise their resources time.

In the document, Cramfield College of Aeronautics, “user costs at airports in Europe, SE Asia and the USA”, it has been established a value of 32.5 euros/minute as the cost of turnaround for medium sized aircraft turnarounds. This means that if we quantify the optimisation in turnaround time (and in particular the reduction of wasted time, due to inaccurate predictions of the landing times), we can calculate the improvement in cost efficiency due to ABCD implementation.

The idea is that from the ground handler point of view having the information about the status of the aircraft means to predict with high accuracy the time the aircraft will arrive at the stand. As a consequence it will have the possibility to optimize its resources and the turnaround times. This means that a better planning of the ground handler can be traduced in shorter turn around times.

6.4.4 Customer service

The increased predictability of departures might enable passengers to be informed in a more efficient way about the flight departure time. A direct consequence could be that passengers instead of waiting at the gate spend more time in the airport increasing airport revenues. This could be considered an airport operator benefit.

6.4.5 Better use of available capacity and increase d impartiality in the slot assignment process

With the implementation of the new ABCD system, the slot allocation list could be updated earlier than with the current system and messages in case of an aircraft flight plan linkage for more than two legs. This possibility of updating the slot allocation list gives to the CFMU the chance to optimise the use of available capacity.

As the allocation slot list could be updated long in advance for airlines providing aircraft registration, these airlines will achieve the same anticipation time efficiency in term of reallocation of their slots and flight management than major airlines dedicating some staff to the task of slot reallocation. Those airlines will get the feeling that there is no

On-Line

information

CFMU Slot

Allocation

List Up-Date

Improved

use of

Capacity

On-Line

information

CFMU Slot

Allocation

List Up-Date

Improved

use of

Capacity



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difference in the slot re-allocation between flag airlines, low-cost, charter, etc. This is one of the important benefits for the small airlines.

6.5 Conclusions

In the one hand, even if the present CBA estimation is not fully developed, the ABCD concept seem to incur low costs as they are likely to involve either the integration of ABCD system to the existing ATC and ATM systems, or the generation of new flight information messages on airports where such messages are not received and processed, but in both cases there will be no radical change to the existing software and hardware.

In the other hand, the ABCD concept potential benefits, which could be generated, seem promising and there are strong chances that the final ABCD CBA would present a positive net present value, showing that this concept brings value to the ATM community.



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ANNEX 1: AIRLINAIR’s INTERVIEW

INTRODUCTION

The objective of this document is to present the results of the interview with the Airlinair’s Operational Control Centre (CCO). The interview was held at Airlinair’s Premises (Orly airport) on Friday 27th of April.

The interview was organised with Mme Dominique Lucas, head of the CCO. She manages a team responsible for activities such as flight planning and tracking, crew management and maintenance support.

The purposes of the interview were to obtain information on the organisational and operational framework of Airlinair, to present the ABCD project to Airlinair and to get her feedback of the presentation of the ABCD concept.

Interview context

The interview, presented in this paper, is part of the WP1 of the ABCD project, which consists in establishing a “state of the art” of the current operations regarding flight planning.

It is the purpose of the “state of the art” work to conduct a series of interviews with operational actors. The development of the ABCD concept requires support among involved actors, including airlines, CFMU and airports.

The interviews process has started with the airlines. Future interviews with airports and CFMU are foreseen and will be presented in the follow up of this study.

List of the interviewed airlines

Recognising that different airlines have different requirements and expectations, the following categories of airlines have been defined: 1. “flag-carriers” or major airlines, 2. “low-cost” airlines, 3. Regional airlines, general aviation or other non-scheduled airline types.

For each of the categories, an airline has been selected for an interview, for an overall coverage of the requirements and expectations regarding ABCD project. Table 4 presents the list of interviewed airlines.

Major Airline Low-cost airline Regional airline

Air France X

Airlinair X

Ryanair X

On air X X

Iberia X

Table 4: List of airlines



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GENERAL CHARACTERISTICS OF AIRLINAIR

Airlinair is a regional type of airline. It provides flight services from Paris to different regions in France and flight services between French regions. The airline, also, acts as an Air France’s subcontractor on liaisons from or to Paris airport. In doing so, it links different regions of France with the hub of Air France at Paris Orly and CDG airports.

Airlinair flights structure breaks down into:

1. Flights operated under Airlinair’s flag;

2. Sub-contracted flights of Air France;

3. Airlinair’s flights outsourced to another smaller regional airline, Chalair.

It’s worth noting that a great part of Airlinair’s activity (80% of flights) is composed by the Air France sub-contracted flights. Airlinair service to Air France is “all inclusive”, which means that both the aircraft and the pilots are Airlinair, operating under Air France’s flag. Air France is responsible for selling the flight to the passengers. These regional flights are generally used by Air France to connect passengers with the hub.

As part of the Air France / Airlinair’s contract, objectives of quality of services are defined, concerning in particular the punctuality and regularity of flights. Air France requires that Airlinair flights ensure punctuality with a 15 min. tolerance window.

Punctuality is also an internal objective of Airlinair. Flights sold under Airlinair’s flag have to be punctual at least 95% of the time, considering the 15 min. tolerance window. Airlinair does not make any difference concerning the causes of eventual delays recognising that the passengers do not make any difference between a delay attributed to the CFMU slot allocation system and a delay attributed to another reason.

For the passenger, the airline is in the front line regarding delays and is always kept responsible of ensuring punctuality. Therefore, Airlinair is very interested on any project that tackles the issue of delays optimisation and propagation. In particular, it welcomes the idea of having a system optimising the allocation of delays by considering the entire journey of an aircraft, making the links between flights, as it is the case in ABCD.

Network’s organisation

The following picture shows the network of Airlinair, including the flights operated under Airlinair’s flag, Air France sub-contracted flights and Chalair’s flights.



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Figure 16: Airlinair’s network

The network is organised on two main “hubs”:

� Paris Orly airport is the main hub of the airline. Airlinair’s headquarters, including the operational control centre are located near the airport (at Rungis);

� Lyon Saint-Exupéry airport is a secondary hub of the airline.

All Airlinair’s flights connect one of these two hubs with regional cities, including: Aurillac, Béziers, Bordeaux, Brest, Brives, Castres, Eindhoven, La Rochelle, le Havre, Poitiers, Mulhouse, Rennes.

The other liaisons indicated in the figure, including the ones in neighbouring countries, are flights integrated into the Air France network (subcontracted Air France’s flights).

Two lines are subcontracted to Chalair: Le Havre – Amsterdam and Paris Orly – Eindhoven.

Airlinair’s fleet

Airlinair fleet (24 aircraft) is composed by propeller’s type of aircraft. The Franco Italian firm ATR manufactures these. Two types of ATR aircraft are operated:

� ATR 72;

� ATR 42.



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Figure 17: Airlinair’s fleet

It can be noted that the fleet is quite homogeneous. The majority of aircraft are ATRs 42. Aircraft affectation to flights is done strategical ly, at least the day before the operations . Aircraft substitution is quite rare, during the day of operations (less than 10% of flights concerned). It could happen exceptionally in case of unexpected failure on aircraft.

Unlike major airlines, which could adapt the size of the aircraft to the latest demand situation for flights, Airlinair is not able to make such an optimisation.

Aircraft’s assignment

A typical aircraft’s journey is composed of 6 flights in average, up to 8 flights in certain cases. Overall, 100 flights are operated per day.

The assignment of every aircraft of the fleet to the individual flights is communicated to involved agents (Airlinair’s representatives, handlers) at each of the airports of operation, the day before the operations. A message is sent, via e-mail, with all actors in copy.

A typical message of aircraft assignment is as follows: (case of the aircraft assignment’s programme for the 27th of April):



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Figure 18: Aircraft’ assignment message

It can be noticed that within the day, up to 8 flights can be assigned per aircraft. For these cases, there are very few margins to adapt the schedule in case of delays. At each airport of the aircraft’ itinerary, the time allocated to the turn-around is very short and has to be optimised.

The Turn around “stop time” (time period between one flight’s arrival – in block and the next leg of the itinerary – off-block) is often set up at a minimum (TTM) value of 30 minutes. In these cases, the turn around processes have to be optimised at a maximum, since the 30 minutes period corresponds to the minimum laps of time required for the boarding and deplaning of passengers, and for the general handling tasks at the airport.

In case of aircraft’s delay, it is thus virtually impossible to recover the delay at aircraft’s stopover. The delay is propagated to the next leg of the itinerary, until a period “off-peak” (i.e. outside peak periods of the early morning and late afternoon).



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According to the CCO, about 80% of flights are concerned with a stop time set up at 30 minutes. Therefore, in a vast majority of cases, delays will propagate to subsequent legs of aircraft’ s journey.

Airlinair welcomes the idea of making the slot allo cation process evolving to a process in which the next legs of aircraft’s itiner ary would be taken into account automatically. They are in favor of a concept such as ABCD.

Airlinair suggests including CFMU in the list of re cipients of the aircraft’ assignment message. In doing so, the CFMU would be provided in advance – one day before the day of operations – with the air craft’ program during the entire journey. With such a message, the CFMU would be able to link the different legs of the aircraft’ itinerary.



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OPERATIONAL CONTROL CENTRE SERVICES DESCRIPTION

The Operational Control Centre (CCO) is Airlinair Operational Headquarter for coordination and control of flights’ programme (incl. planning and monitoring of real-time execution of flights).

General organisation

The CCO’s overall objective is: “to comply with the scheduled flights’ programme, the one “sold to the clients (Air France and Airlinair’s own passengers)”. At the CCO, airlinair has an application that displays the evolution, in real-time, of two performance indicators: punctuality (global) and regularity (global).

Activities such as:

� Flights’ tracking;

� ATFM slots’ management;

� Aircrafts’ permutation;

� Flights’ cancels.

are performed at the CCO, where all decisions for flights’ management are taken.

One single team composed by a “chef de quart” and an assistant to the “chef de quart” are responsible for all of the above-mentioned activities. The “chef de quart” is the one who dialogues with CFMU (i.e. who send initial FPLs and eventual modifications to the flight plans, e.g. delays, who receives the allocated slot and eventually who tries to re-negotiate the slot).

The “Flights’ tracking” activity is reduced to the monitoring of the aircraft’ actual take-off times. A MVT (Movement) message is sent by Airlinair’s agents or by a handling agent to whom the task is subcontracted, at each of the airports of operations. This message gives the actual take-off time of the aircraft.

Airlinair’s aircraft are not equipped with ACARS. Therefore, it is the pilot, via a dedicated frequency, who communicates the actual take-off time to the agents.

The MVT message is the only reporting message that informs the CCO about the status of the aircraft: delayed or on time.

When a slot is allocated to a flight, the slot is quite difficult to “re-negotiate” by Airlinair. For most penalizing cases, they still can contact CFMU directly (by phone) to re-negotiate.

When the flight corresponding to the previous leg of the aircraft’s itinerary has been delayed, the CCO’s strategy is to wait until the very last moment, to communicate about the delay.



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A DLA message will be sent to CFMU only when the CCO is sure that it can’t be recovered either during the turn-around process or when an ATFM slot has not been allocated to the flight. If such an ATFM slot has been allocated, which absorbs the delay of the previous flight, the DLA message is not sent.

In doing so, Airlinair wants to make sure they will not be penalised by the slot assignment process, since they think that any modifications to a flight plan that is already within the CFMU database constitutes a risk of being repositioned at the “end of the queue” of the slot allocation list.

As previously mentioned, the proportion of flights, for which an aircraft’ permutation is applied is low, less than 10% of Airlinair’s flights. Therefore, the aircraft assignment programme – as defined the day before the operations - is generally “stable”. For cases, where it is required (e.g. unpredicted aircraft’ failure or exceptional commercial constraint), Airlinair has one spare aircraft at its hub of Paris Orly and one spare aircraft at its hub of Lyon for permutation.

Flight cancellation is even more rarely applied since Airlinair has reliability objectives of performance to comply with (nearly 100% - 98% - of flights have to effective).

Flight Data existing structures within the CCO

Depending on the time scale and the current Airlinair flight’s operations situation, the CCO manages the following flight data structures: schedules, RPLs, FPLs, aircraft assignment programmes, flight progress messages.

� Commercial Schedules / RPLs

Schedules are defined two times per year, for a six months period: summer and winter seasons. The summer schedule is finalised at the end of March, for a start in April. The winter schedule is finalised at the end of October, for a start in November.

Schedules are prepared one month in advance (i.e. the summer schedule is prepared at the beginning of March), taking into account commercial parameters (passenger demand, Air France demand), slots at co-ordinated airports (Orly) and technical parameters (aircraft fleet, etc.).

Once the schedules are defined, RPLs (Repetitive Flight Plans) are prepared for submission to CFMU (including origin and destination airports, call sign – flight ID, aircraft type, EOBT and estimated duration of the flight). However, the aircraft registration is not available at this stage, since aircraft are assigned later, the day before the day of operations.

RPLs start to be prepared 15 days before the end of March (summer schedule) or October (winter schedule). They are valid for the entire summer or winter seasons. The CFMU receives a list of the RPLs for the summer at the end of March, and a list of the RPLs for the winter at the end of October.



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RPLs will automatically generate individual FPLs in the CFMU system, the day before the day of operations.

According to the CCO, the list of RPLs is relatively stable and rarely modified (homogeneous fleet of aircraft, few changes of the route).

RPLs constitute the vast majority of flight plan types submitted to CFMU: 98% of Airlinair flights are RPLs (2% are FPLs).

� FPLs

As mentioned, the flights are generally planned via RPLs submitted to CFMU at the beginning of each summer or winter season. However, in a few cases (2%), FPLs are submitted.

A FPL could be submitted for a flight related to the convoying of a spare aircraft from one of the hubs (Orly or Lyon) to an airport, where an aircraft is needed for substitution (e.g. aircraft failure). Another type of flights, eventually eligible for FPLs are non-scheduled type of flights, such as charters.

When FPLs are submitted, they are in vast majority of cases (70%) sent the day before the operations to CFMU.

� Aircraft assignment programme

As already mentioned, aircraft assignment is a daily activity performed one day before the day of operations of the flights to which the aircraft are assigned.

The aircraft assignment programme is sent via e-mail to all agents and handlers at the different airports of operation.

In the context of ABCD, Airlinair would suggest to include the CFMU as an additional recipient of the e-mail. The airline expects the CFMU to be able to take into account the format of the message, as the current format is used by the various operational agents responsible to manage the turn around process of the aircraft at each of the airports of operation.

Therefore, Airlinair not only agrees to submit with anticipation (one day before the operations) the aircraft registration for each flight but hopes it will be systematically used by the CFMU systems as a mean to optimise the slot allocation system.

More over, Airlinair insists that CFMU should take into account constraints inherent to the turn around and in particular the time period for turn-around. They are ready to communicate the information on the time allocated to the turn-around systematically (e.g. 30 minutes TTM for 80% of flights, as already mentioned).



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� Flight progress messages – MVT message – Delay management

In the absence of ACARS equipment, the CCO monitors the progress of the aircraft via a MVT message. The MVT message is sent by the agent who is at the airport where the aircraft takes-off. It informs the CCO about the actual take-off time and about the number of passengers. An example of MVT message is provided below:

Figure 19: MVT message

In the example above (Rennes – Toulouse Air France flight subcontracted to Airlinair), the flight had an EOBT set at 13:10 and took off at 13:16 (Actual Take-Off time).

Through the MVT message, the CCO can be notified of any delay inherent to the flight. Since an airlinair flight lasts in average 1 h 15, an eventual delay, which would propagate to the next leg of an aircraft itinerary, is thus communicated with 1 h 15 anticipation to the CCO.

However, the notification of delay to the CCO does not necessarily triggers the immediate sending of a DLA message to the CFMU, even when the delay exceeds the rule which requires that for delays exceeding 15 minutes a DLA message with updated EOBT has to be sent to CFMU.

Indeed, the strategy, as far as the CCO of Airlinair is concerned is to wait until the very last moment to notify the CFMU of the delay of a flight, in order to secure the flight’s position into the slot allocation list, in case of regulation. Since the rule is “first planned, first served”, Airlinair thinks that the risk of being allocated a “bad” slot is higher, when a modification to the flight plan is submitted, as the modification could position the flight at the end of the slot allocation list.

In addition, a DLA message for the next leg of the aircraft itinerary is only sent if the duration of the turn around process makes impossible to absorb the delay at the airport of transit and if the flight that risks to be delayed is not already constrained by a higher delay allocated by CFMU.

In any cases, with such a strategy, the CFMU is usually notified with very little anticipation of a delay.

Therefore, a concept such as ABCD would also benefit the CFMU in notifying the delay in advance from the moment it is detected on the previous legs of the aircraft itinerary (since CFMU would be able to make the link between the different legs of the aircraft itinerary).



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EXPECTATIONS REGARDING FUTURE CFMU DEVELOPMENTS

According to the CCO, there are two main issues to address with future evolutions of CFMU:

� Airport slot – ATFM slots inconsistency;

� Linkage of the different legs of an aircraft daily itinerary.

The first issue has to deal with the fact that the capacity that is defined strategically should be aligned – as far as possible – with the nominal capacity available on the day of operations. Airlinair does not understand why nominal ATFM regulations are still regularly applied to deal with airspace or airports congestion while they have to negotiate a limited number of airport slots strategically in order to manage such limited resources of capacity.

More generally, they insist that a central organism , such as CFMU, has to act as an impartial referee, for the allocation of slots. They have sometimes the feeling to be disadvantaged when they have to renegotiate o r negotiate the slots, either airport slots or ATFM slots.

The second issue is of direct scope of the ABCD study. Airlinair wants the links between flights be taken into account into the logic of the slot allocation system and is ready to communicate to CFMU the information required for that purpose: aircraft registration for all flights, via the aircraft assignment’ programme and information on the turn around processes duration.

The CCO welcomes the flight planning assistance from CFMU, such as re-rerouting options in case of ATFM delays.

However, the CCO insists that they want to keep full authority and flexibility for the planning of the flights, in case of unexpected events. Therefore, in the implementation of such an ABCD concept, mechanisms for updating the flight plan have to be kept.



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ANNEX 2: ON AIR’s INTERVIEW

ONAIR AND EUROAIR: INTRODUCTION & GENERAL CHARACTER ISTICS

This chapter presents the results of the interview with On Air and EuroAir Operational expert which was held in OnAir premises in Pescara (Italy) the 2nd of May 2007. The interview was organised with the responsible of operations, flight planning and route development.

The objective of the interview was on one hand to collect information about the current organization inside the airline company concerning the way they manage the fleet mix, the aircraft assignment and the communications with other airport actors, and on the other hand to present the objectives of ABCD project and to investigate benefits from the airline point of view and possible airline expert suggestions in relation to ABCD project objectives.

On Air is the commercial trade-mark of Sinclair srl, company committed to develop new routes from Pescara Airport to international destinations in co-operation with SAGA spa (Pescara Airport Management Company) and with the Abruzzo region.

The company mission is to increase the incoming tourism to Abruzzo.

European Airlines Ltd” or “Euro Air Ltd” was founded in 1995 and certified by the Hellenic Civil Aviation Authority and the Ministry of Transportation to offer its services for charter, cargo, mail transportation and medical evacuation flight.

Following the completion and commencement of operations from the new International Airport of Athens (A.I.A.) EuroAir relocated into its new offices in the airport.

Today, EuroAir Ltd. with a total fleet of seven aircraft (2 MD82, 2 British Aerospace ATP of 66 seats each and one Let 410 19 seats, and 2 Piper Chieftain 8 passenger seat each) is the third biggest company in Greece in terms of fleet size.

Network Organisation

This document focuses the attention on Euro Air organisation, but since Euro Air operates for On Air, the description of the route organisation and the frequencies of flight are related to On Air company.

Following there is the picture with the destinations served by On Air.



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Figure 20: On Air’s network

Those operate by Euro Air are: Paris, Charleroi, Split, Bucarest and Creta.

Euro Air Fleet and Aircraft assignment

EuroAir fleet is composed by seven aircraft: 2 MD82 of 162 seats, 2 British Aerospace ATP of 66 seats each and one Let 410 19 seats, and 2 Piper Chieftain 8 passenger seat each, but the fleet which operates for On Air is made of the 2 MD82.

The flights to Paris, Charleroi, Split, Bucarest and Creta are operated by Euro Air using MD82 with 162 seats.

Concerning the information about the aircraft type, this is provided at the beginning of each season (summer and winter) together with the RPL, and since the fleet is composed by two MD82, the aircraft type will never change with respect to the information given in the RPL.

After the repetitive flight plan submission at the beginning of the season, 24 hours before the flight, the airline company sends the information of the aircraft type together with the aircraft registration number. This information could change, as instance because of maintenance problems, and there could be modifications in the registration number which have to be communicated by the airline company.

During Euro Air interview the expert explained that aircraft substitution is not that rare in the case of Euro Air.



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OPERATIONS: GENERAL ORGANISATION

All activities like flight planning, aircraft assignment, aircraft registration number modification, flight tracking, etc., are made in the operational centre.

At the moment, flight tracking is made with the use of MVT messages (Movement messages) which are sent by the handling company to the airport. The content of the message is the actual take-off time of the flight which is the only information the airline possesses about the aircraft status.

Concerning delays, the airline company normally waits until EOBT + 10’ to communicate the delay thought the delay message (DLA) in order to receive a new CTOT and not to loose priority in the slot allocation process. The possibility to loose priority and to be inserted at the end of the slot allocation list is a high risk for the airline company, for this reason they try to wait until the last moment and to be sure that the delay cannot be recovered, and only in this situation they send a DLA message to communicate the delay.

Concerning FPL, Euro Air schedules its flights two times per year, for the winter and the summer seasons which have to be decided and delivered respectively in October and in March. Once the scheduled have been agreed the RPL are prepared and sent to the CFMU for approval. As previously mentioned, at the RPL submission the only available data about the aircraft is the aircraft type, while the registration number is an information which is given 24 hours before the flight.



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EURO AIR POINT OF VIEW ON ABCD PROJECT

During the interview the representative of Euro Air operations has shown very clearly his positive opinion on ABCD project. He expressed the importance for the airline company of the availability of on time information about the aircraft status during the different segments of the aircraft daily itinerary, in order to take internal decisions for example in case of delay.

Euro Air already provides the information about the aircraft registration number in advance (24 hours before the flight schedule time).

The interviewed expert expressed his doubts about the aircraft substitution in the last hours before the EOBT. He underlined the limit of the availability of aircraft registration number without the update of this data until the very last moment before take-off. In fact, he said that even if Euro Air has a limited fleet at the moment, which is composed of two MD82, he has been working for other airline companies with fleet mixes composed by less that 10 aircraft, and even in those cases the aircraft substitution was not something rare to happen. In the case of substitution he thinks that there should be an action from the airline company to communicate the registration number change in order to keep the advantages of the project and to be able to track the flight in the following legs of its itinerary.

In the case of On Air and its flights operated by Euro Air, it is possible to see how the delay on a certain segment of the aircraft itinerary could have effects on the following segment. Looking at the schedule, there are examples of flight coming from Crete and going to Paris through Pescara, where the time between the two flights, the turnaround time is 45 minutes. For those flights it becomes evident that the delay on the Crete-Pescara segment could have a propagation effect on the following Pescara-Paris segment.

For those reasons the airline company totally supports ABCD project.



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ANNEX 3: AIR FRANCE’s INTERVIEW

INTRODUCTION & GENERAL CHARACTERISTICS

This chapter presents the results of the interview with the Air France Operational Control Centre (CCO), which was held in Air France premises in CDG airport (France) the 22nd of May 2007. The interview was organised with the responsible of the ATC Slot cell, the responsible of CDM implementation project at CDG airport (CDM@CDG) and the responsible of flight planning tools and software development.

The main objectives of the interview were to collect information concerning the way they manage the fleet mix, the current information flows during the planning process and the operation of the aircrafts, the aircraft assignment and the communications with other airport actors, and to present the objectives of ABCD project in order to know the experts’ opinion and the possible airline’s interest in such a development.

Air France is France’s flagship airline, operating since 1933. Its offering is composed by domestic and international scheduled passenger and cargo services to 225 destinations in 88 countries around the world. Overall, 1800 flights are operated per day.

Its main bases are Orly Airport and Charles de Gaulle International Airport, both in Paris, with a hub at Saint-Exupéry International Airport, Lyon.

Air France has developed a regional network. This network is operated with flights subcontracted to regional airlines, such as Airlinair or with flights operated by Air France’s subsidiaries: Britair, Régional, CityJet. These regional airlines operate regional jet and turboprop flights.

The Air France passenger fleet consists of the following aircraft as of June 2007:

� 145 Airbus A318-319-320-321;

� 16 Airbus A330;

� 19 Airbus A340;

� 12 Boeing 747;

� 43 Boeing 777.

Other activities apart from the transport of passengers and cargo are aircraft maintenance and handling services.



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OPERATIONAL CONTROL CENTRE SERVICES DESCRIPTION

The following picture shows the hierarchical and operational structure of the CCO:

Figure 21: Air France’s CCO

Functional presentation

The CCO is the Air France Operational Headquarter for coordination and control of flights’ programme.

The CCO’s overall objective is: “to comply with the scheduled flights’ programme, the one sold to the clients” (the passengers). At the CCO, Air France has a set of applications that displays the evolution, in real time, of the punctuality / delays of flights. The applications work with data from different sources, like the MVT (Movement Messages), DEP, ACARS (aircraft messages) and CFMU messages.

The data (time estimates, actual times) is processed by flight management systems (in-house developed). Data come from several sources: handling agents (MVT message), aircraft (ACARS), ANSP (DEP), CFMU (CTOTs). With the received information, the Flight Management System is able to forecast the flight operating times of the remaining flights of the aircraft’s planned sequence.



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The information feeds systems (SIROCCO as described in further sections – Tools Description) which analyse conflicts like delays, lack of flight crew, late connection passengers, etc. These analyses are used by the personnel of the CCO to take decisions concerning:

� ATC slots’ re-negotiation;

� Flights’ cancellations (frequently implemented);

� Aircrafts’ permutation (frequently implemented);

� Crew modification.

All decisions for regulating flights are taken at the CCO. The impacts are managed up to the next three days, after the day of operations.

In case of major events the CCO can set-up a “crisis task force”.

SERVICES DESCRIPTION

Le Chef de Quart / Duty Manager

He / She is the “chef d’orchestre”, defines strategy and guidelines of the operations on the flights’ programme.

The Duty Manager works under delegation of Air France General Director, which means full autonomy for taking important decisions (for example, a long-haul flight cancel or a long-haul flight shift to the next day).

Les Chefs de Quart Adjoints / Deputy Duty Managers

The CCO operations are structured as follows:

� Long Haul & Cargo;

� Hub Medium Haul;

� Orly and point-to-point Medium Haul (France);

� Partners.

Each sector is managed by two Deputy Duty Managers.

In a real CDM environment (input provided by the different CCO services), they manage the flights’ programme during the day of operations (D-day), with the objective of reducing the impact of external events (irregularities).

From 17h UTC onwards, they start managing the impact of their decisions on the D-day +1.

La Regulation Programme / Flights Scheduling

The Programme Service (PH.PC) is in charge of preparing the season flights’ programme, 6 (six) months in advance, according to given criteria (safety, IATA conference commercial slots, clients, long term fleet availability, long term crew



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availability….). Once the programme has been completed, RPLs are prepared for submission to CFMU (including origin and destination airports, call sign – flight ID, aircraft type, EOBT and estimated duration of the flight). They are valid for the entire summer or winter seasons.

RPLs will automatically generate individual FPLs in the CFMU system, the day before the day of operations.

RPLs constitute the majority of flight plan types submitted to CFMU, for short-haul and medium-haul flights: 70% of flights are RPLs. For long-haul flights, FPLs are used exclusively. When FPLs are submitted, they are sent 5 to 6 hours before departure to CFMU.

At this strategic stage (flights’ programme preparation, RPL preparation), the flights in the programme have been assigned a category of aircrafts, and not a specific aircraft. The association (“matriculation”) will be performed by the Maintenance Regulation.

The Programme representative and the Deputy Duty Manager have similar responsibilities about the flights’ programme, on different timescales: the DDM handles the programme mainly during the D-day while the Programme representatives’ look-ahead is from D-day +1 to D-day +7.

La Maintenance au CCO / Maintenance Regulation

As far as the planning phase is concerned (D-day +1 to D-day +7), the Maintenance assigns an aircraft to a given flight (“matriculati on”), according to different available data :

� Fleet status;

� Number of expected passengers per flight;

� Crew availability.

The Maintenance Regulation provides in real-time (24h / 24, 7d / 7) the CCO with information about the fleet status. Information sharing between the different CCO actors and the Maintenance is fundamental: to let the CCO Duty Manager (and Deputies as well) define the strategy and manage the D-day flights’ programme three meetings between Maintenance and the Deputy Duty Managers take place during the day of operations (6h45, 10h00, 15h15).

La Cellule Commerciale / Commercial Desk

The Commercial Desk is the “clients’ voice” at the CCO. Commercial criteria (type of passengers, number of passengers, passengers in correspondence and related costs) are keys for building the scenario that will be run by the Deputy Duty Manager:

� during the day of operations the Commercial Desk identifies the flights eligible for cancellation the D-day +1;



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� They identify as well flights “sensible” for the next three days (D-day +1 to D-day +3), i.e. flights whose cancellation would result difficult to manage (few passengers re-routing solutions, or strategic flights for Air France, ….).

The Commercial Desk is also in contact with the SkyTeam Partners’ CCOs in order to coordinate the passengers’ management policy when major events occur.

Le Representant PNT / Duty Pilot

The Duty Pilot manages the link between the pilots and the CCO: feedback / expertise to the CCO, information sharing and communication between PNT (Personnel Navigant Technique) and CCO.

Le Permanent Commandement PNC / Cabin Crew Duty Off icer

Same role like the Duty Pilot for the Cabin Crew.

Les Regulations des PN / Crew Regulation

The Crew Regulation insure (D-day to D-day +1) the correct deployment of pilots (PNT) and crews (PNC), according to institutional and operational (flights’ programme) rules / constraints.

They manage the consequences of modifications on the PN (Personnel Navigant) planned deployment: by elaborating scenarios in advance (as much as possible), they aim at minimising the impacts of irregularities. The scenarios must take into account the following constraints:

� PN planning (including working and resting time);

� PN Flights’ Division;

� Inducted costs (hotels, transport, working time shifting…);

Each modification of the PN deployment automatically feedbacks the PN planning unit (system sharing), which is in charge of the PN deployment planning up to 1 (one) month in advance.

As an example, the time necessary (institutional rule/constraint) to a pilot for a turning round (between 2 long haul flights) is:

� 10 hours stay at the hotel;

� 0h 30min for transport to the airport (up to 1 hour);

� 1h 15min for flight briefing + debriefing.

� 11h 45min (minimum) total time.

As far as the crew is concerned, the total time is 11h 00min if the current flight time is > 6h 00 and the next (planned) flight time is > 6h 00 as well, but it can be reduced down to 8h 00min (minimum) if necessary.

Les Representants d’AFR Cargo / Air France Cargo Du ty Officer

Air France Cargo fleet is composed of



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� 3 Boeing 747-400ERF;

� 9 Boeing 747-200;

� 1 Airbus;

� some Boeing 737 (depending on the needs).

Cargo flights’ are subject to a specific flights’ planning, defined by the Programme Service (Cargo Unit) 6 (six) months in advance (IATA Conference).

As the Cargo activities depend on the time period (winter vs. spring/summer) and the Industry clients, the deployment of the flights’ programme starts quite late (w.r.t. the passengers’ flights programme): D-day – 14.

The Cargo representative is in charge of the flights’ programme management (55 flights / week), by applying the same strategy when external events occur: come back to the scheduled flights’ programme as soon as possible.

As far as the operational resources are concerned, the Cargo programme operates like the passengers programme does: maintenance, PNT, dispatch…

Le Dispatch / The Dispatch Service & The Flight Pla nning

The Dispatch service, in charge of the Long Haul flights’ tracking, is the main support, during the flight, to the pilot and the crew in terms of safety. This role is played respecting the autonomy of the pilot.

The Dispatch service plays also an important role when supporting the Flight Planning Unit: by the use of the Meteo France forecast tool, Dispatch provides the Flight Planning Unit with the latest weather information in order to prepare / fill an optimal flight plan (the flight planning process starts at ETD-7h and ends ETD-3h, when the flight plan is delivered to the CFMU system).

La Cellule ATC Creneaux / The ATC Slot Cell

The ATC Slot Cell, at the CCO under the Duty Manager operational responsibility, is part of the Flight Planning Central Unit (Etude Central des Vols). This means that they can act, depending on circumstances, as flights’ planners or slot allocation “managers”.

The mission of the ATC Slot Cell is to manage the slots allocated by the CFMU, as far as the en-route airspace is concerned; in fact, TMA slots are quite difficult to “re-negotiate”.

Depending on the regulated sectors and the current traffic situation, the ATC Slot Cell tries to anticipate the best routing solution. If this is not possible, they try to improve the slot allocated in order to align it with the ETD (for Air France corresponding to the EOBT).

In practice, they receive all their flights’ ETDs (Medium Haul over the network and Long Haul departing from CDG) and optimise them by the use of internal tools (see the tools description section) and the CFMU system (which can propose re-routings’ options as well). For most penalizing cases they contact CFMU directly or the ACC centre (slot re-negotiation).



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When the flight is delayed and cannot comply with an allocated slot (as a consequence, for example of the late arrival of the previous flight, which shares the same aircraft), these are the strategies applied:

1. if the delay is more than one hour, a DLA message is sent to the CFMU IFPS;

2. if the delay is less than one hour, the strategy is to wait until the very last moment, to communicate about the delay.

For example, the strategy can be to wait until EOBT + 10’ to communicate the delay thought a delay message (DLA), so as to not loose priority in the slot allocation process. The possibility to loose priority and to be inserted at the end of the slot allocation list is a high risk for the airline, for this reason they try to wait until the last moment and to be sure that the delay cannot be recovered, and only in this situation they send a DLA message to communicate the delay.

TOOLS DESCRIPTION

The “Main Courante CCO” tool

Accessible via the CCO Intranet, it shows and notifies to the different services all the main events occurring during the D-day.

The “Tableau de bord” tool

Accessible via the CCO Intranet, this application displays the evolution, in real-time, of the following performance indicators:

� Punctuality (global or per aircraft type);

� Regularity;

� Passengers (estimated vs actual).

At the end of the day, the Duty Manager uses these data to prepare the D-day report, detailing the major events occurred, the punctuality indicators, delays and their causes, passengers, compliance to the flights’ programme.

The “SAILOR” tool

The “Systeme d’Assistance Informatique gLobale aux OpeRations”, SAILOR, is the graphic tool used by the Dispatch to track the Long Haul flights.

SAILOR can display the aircraft position derived from different data sources:

� Estimated position from OCTAVE (the flight plan calculator taking into account the ATD);

� Radar track position provided by USA, Canada, and UK ATC;

� ACARS.

Moreover, SAILOR can display on a geographical map (overlaying the different graphic data):

� Flight plan data;



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� Infrastructure data (airways, airports, waypoints…);

� Weather data pictures (satellite infrared and visible data, predicted data, model data such as winds and temperatures) provided by SYNERGIE (Meteo France weather forecast tool).

The “SIROCCO” tool

The “Systeme Informatique de RegulatiOn du CCO” is a support to decision making tool used by different CCO Services.

It consists of three modules (three tools in one), fed by a common database (80 information flows), allowing the CCO D-day flights’ programme exploitation: air, ground and commercial anticipation.

SIROCCO Vol is the module used by the Deputy Duty Managers for identifying aircrafts eligible to be swapped: different regulation options and their consequences (delays, passengers in correspondence, and PN) can be taken into account, in order to find out the best possible solution.

SIROCCO Sol is the module used by the Maintenance to perform the registration of aircrafts to the flights’ programme for the day of operations.

SIROCCO Commercial is the module used by the Commercial Desk to identify the most “sensible” flights (eligible for cancellation on the D-day +1). If a specific flight is delayed, how many passengers will skip their correspondence? If a specific flight is cancelled, which options for passengers re-routing? How much would it cost the assistance to not on-boarded passengers? Etc.

According to criteria defined by the user:

� Commercial priority;

� Passengers number;

� Financial criteria;

� Night-stops;

� Crew rotation;

� Frequency;

the module will finally propose a list of eligible flights.



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Figure 22: SIROCCO’s display

SIROCCO can be regarded as an in-house comprehensiv e “ABCD” like system since it makes the link between the different fligh ts scheduled with an aircraft. It uses the aircraft registration to make this link. W hen an aircraft is delayed, it identifies the flights, which are impacted by the d elay, and proposes a list of eligible flights for aircraft swapping or cancellat ion.

Then, Air France interest on another ABCD service i s limited since they feel that the ABCD concept is not refined and supple enough t o meet their own specific needs (dynamic swapping, hub management).



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AIR FRANCE POINT OF VIEW ON ABCD PROJECT

During the interview the representatives of the Air France CCO have made it clear that they already have a dynamic and supple “ ABCD like” way of operating their flights.

For instance, they have internal in-house comprehensive systems (like SIROCCO), which give on time information about the aircraft status during the different segments of the aircraft daily itineraries, in order to take optimised decisions for example in case of delays.

Therefore, the interviewed experts expressed their doubts about the added value for Air France of implementing another “flights linking” concept, such as ABCD. In fact, they said that they require flexibility to substitute their aircraft or to cancel flights as they regularly do, and they want to keep full control of the management of delays.

They think that the ABCD concept, as it is defined, and under “management” of the CFMU (for the linking of flights), is not refined and supple enough to meet their needs (dynamic swapping, hub management).



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ANNEX 4: RYANAIR’s INTERVIEW


This chapter presents the results of a telephone interview with a Ryanair pilot, Mr Pierre Bogart, which was held the 4th of April 2007.

The main objectives of the interview were to collect information concerning the way they manage the fleet mix, the current information flows during the planning process and the operation of the aircrafts, the aircraft assignment and the communications with other airport actors, and to present the objectives of ABCD project in order to get to know the possible airline’s interest in such a development.

Ryanair is an Irish airline headquartered in Dublin; however, its biggest operational base is at London Stansted Airport. It is Europe's largest low-cost carrier and it is one of the world's largest and most successful airlines (whether in terms of profits, number of flights, number of passengers flown).

Ryanair is the largest airline in Europe in terms of passenger numbers.

Network Organisation

Following there is the picture with the destinations served by Ryanair (red + yellow dots).



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Figure 23: Ryanair’s network

Ryanair serves 362 routes between 130 airports in 20 European countries. Ryanair’s hubs are highlighted in red. Its main hub is London Stansted Airport, with 88 routes. Ryanair has other hubs throughout Europe, at Dublin, Charleroi Brussels South, Cork, Frankfurt-Hahn, Nantes Atlantique Airport, Girona, London Luton, Liverpool, Milan Orio al Serio, Pisa, Nottingham East Midlands, Glasgow Prestwick, Rome Ciampino, Shannon, Stockholm Skavsta and has announced three new hubs at Marseille Provence, Madrid Barajas and Bremen (from 1 April 2007).

The airline's first new routes outside Europe began in October 2006 when Ryanair planned to begin flying from Frankfurt-Hahn to Marrakech and Fez, both in Morocco.

Most regional airports from which Ryanair operates are located very far from the city centres than their main airports, with Frankfurt-Hahn perhaps the most notorious example, 140 km west of Frankfurt. There are however rare exceptions: Gothenburg City Airport is 11 km closer to Gothenburg than the main Landvetter Airport, Madrid Barajas which is the main airport and is served by the city subway, and Ciampino



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Airport is 17 km closer to Rome than the main Leonardo Da Vinci International Airport, although the latter is better connected.

Ryanair Fleet, Aircraft assignment, Turn around pro cesses

The Ryanair fleet consists of one single type of aircraft: 137 Boeing 737-800, of 189 seats.

The information about the aircraft type is provided at the beginning of each season (summer and winter) together with the RPL. RPLs constitute the vast majority of flight plans submitted to CFMU. Since the fleet is composed by only one type of aircraft, the aircraft type will never change with respect to the aircraft type information given in the RPL.

Overall, the assignment of every aircraft of the fleet to individual flights is established in advance, several days before the day of operations. However, the aircraft registration information is not given in the RPL.

During the interview, Mr Bogart explained that airc raft substitution is very rarely applied in the case of Ryanair . The aircraft registration information is confirmed 24 hours before the flight, to involved agents (Ryanair’s representatives) at each of the airports of operation, and is generally “definitive” (no swap of aircraft performed).

The aircraft turn around “stop times” are often set up at a minimum TTM value of 30 minutes (time period between one flight’s arriva l and the next leg of the itinerary). In these cases, the turn around processes have to be optimised at a maximum, since the 30 minutes period corresponds to the minimum laps of time required for the boarding and deplaning of passengers, and for the general handling tasks at the airport.

In case of aircraft’s delay, it can be very difficult, therefore, to recover the delay at aircraft’s stopover.



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OPERATIONS: GENERAL ORGANISATION

All activities like flight planning, aircraft assignment, aircraft registration number modification, flight tracking, etc., are made in the operational centre, at Dublin.

At the moment, flight tracking is made with the use of DEP messages which are sent by the departure aerodrome (Control Tower), to the operational centre. The content of the messages is the actual take-off time of the flight which is the only information the airline possesses about the aircraft status.

The airline has no dedicated ground handlers at its airport of operations, as part of its cost cutting general policy.

During the interview, Mr Bogart highlighted that Ryanair has a very “light” handling and manual process of the delays. Basically, the company transmits the delay to CFMU as soon it is notified to the operational centre (at reception of DEP messages), thought a delay message (DLA).

Therefore, Ryanair welcomes the idea of making the slot allocation process evolving to a process in which an automatic flight plan update service would be provided (i.e. which would replace the “manual” sending of DLAs, as it happens today). According to Ryanair, this could reduce the costs inherent to the manual handling of DLAs.

Concerning FPL, Ryanair uses RPLs (Repetitive Flight Plans), where the only available data about the aircraft is the aircraft type. However, the registration number is available in advance, and confirmed 24 hours before the flight.

Ryanair would agree to transmit to CFMU the aircraft registration in advance – e.g. one day before the day of flight. With such a message, the CFMU would be able to link the different legs of the aircraft’s itinerary.



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RYANAIR POINT OF VIEW ON ABCD PROJECT

During the interview the representative of Ryanair has shown very clearly his positive opinion on ABCD project. He expressed the strong interest for the airline company in an automatic flight plan update service, which could be handled directly by the CFMU, and “alleviate” the current handling of DLA messages.

Ryanair operates a single type of aircraft type. The aircraft are assigned in advance to flights and the information could be provided to CFMU at least 24 hours before the flight schedule time.

The interviewed pilot confirmed that aircraft substitution is virtually never applied. In fact, the airline has very few margins for this since the entire fleet is continuously operating. More over, the airline has not a “central” hub strategy, as other major airlines such as Air France or Iberia. The aircraft are not based at a single central base. Rather, the aircraft are spread over many different bases and are therefore hardly interchangeable.

For those reasons Ryanair totally supports ABCD pro ject.



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ANNEX 5: IBERIA’s INTERVIEW


This chapter presents the results of the interview with Iberia Operational expert which was held in Iberia’s premises in Madrid-Barajas (Spain) the 7th of June 2007. The interview was organised with the Flight Watch Division Manager (Flight Operations Management).

The main objectives of the interview were to collect information concerning the way they manage the fleet mix, the current information flows during the planning process and the operation of the aircrafts, the aircraft assignment and the communications with other airport actors, and to present the objectives of ABCD project in order to get to know the expert’s opinion and the possible airline’s interest in such a development.

Iberia is Spain’s flagship airline, operating since 80 years ago. Its offering is divided in four main groups:

� Air Shuttle Service between Madrid and Barcelona;

� European Flights;

� International flights;

� Transatlantic flights, where Iberia is leader in the Europe - Latin America Market.

Other activities apart from the transport of passengers and cargo are aircraft maintenance and handling services.



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PLANNING AND OPERATIONS: INFORMATION FLOWS The planning process begins with the definition of the sequence of flights to be operated for each aircraft of the fleet. At this step, the aircrafts aren’t identified yet, which means that each sequence of flights has not an assigned aircraft registration. The next step is to allocate the available aircrafts to the sequences of flights defined. The day before the flight operation, the Material Division defines all the flights to be operated by each specific aircraft. This information is one of the inputs of the Flight Management System. The output of the Flight Management System is the day’s flight programme, which is transmitted to many other systems that integrate this information and use it for different purposes. During the day of operation, this system receives other data from different sources, like the MVT (Movement Messages) that are sent by the handling agents in the departure or destination airport. Another important input received by the Flight Management System is the CTOTs assigned by Eurocontrol for the day’s flights, essential for planning the operation. With the received information, the Flight Management System is able to forecast the flight operating times of the remaining flights of the aircraft’s planned sequence. This information feeds in Real Time another system called SIRIO, which is a diagnosis and analysis tool. SIRIO analyses conflicts like delays, lack of flight crew, late connection passengers, etc. These analyses are used by the personnel of Network Control Department to take decisions concerning flight programmed delays, changes of aircraft, changes of crew, etc. Further developments of the Flight Management System and the diagnosis tool include the automatic creation of messages like the DLY (delay messages) that are to be sent to Eurocontrol. The new system including these developments is intended to begin working on September-October. In conclusion, Iberia already operates its network on an ABCD-similar concept, which shows the importance and interest of keeping on developing this programme. The following pictures describe the information flows: flight planning and tracking at Iberia.



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Figure 24: Iberia flight planning

Figure 25: Iberia flight tracking



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ANNEX 6: CRCO (Central Route Charges Office) REMARK S

This chapter presents the remarks of a CRCO Eurocontrol expert (Mr Georg Schneider), on ABCD. The remarks were provided after delivery of the first draft version of the present document (25th of June 2007), and confirm the interest for the CRCO, in the project.

Following is a note drafted by Mr Schneider, highlighting selective issues for ABCD, and describing requirements for aircraft identity information. Subject: ABCD Aircraft based concept development

Availability of aircraft identity (airframe) information (registration markings and/or 24 bit aircraft address)

In a competitive environment, aircraft operators need to optimise utilisation of their capital (= aircraft), which amongst others can be achieved by optimizing aggregated flight and turn around times in accordance with planning (and to ca tch up upon delays). ABCD is a supporting concept for such a goal. This goal needs to be matched with that of overall ATM capacity optimisation

As I understand, ABCD would amongst others require a reliable feed of aircraft identity information (aircraft registration markings and/or 24-bit aircraft address + up-to-date conversion tables) all:

� at the planning phase (baseline against which the performance is measured and adjustments are to take place);

� during the operation phases (aircraft movements in the air and on the ground) to closely monitor the progress / delay of a given aircraft (airframe clearly identified by its registration/tail number and/or 24-bit aircraft address);

� during the post operation phase, to consolidate and analyse airframe performance as opposed to ATM/airport performance from a network optimisation perspective.

It was of great interest to the CRCO to learn about this concept, which notably requires knowledge of the aircraft identity (i.e. the airframe in terms of the aircraft registration marking and/or 24-bit aircraft address). I believe that ABCD would be a further logistics application in support of mandatory mentioning of the aircraft identity on the FPL. You may know that Francis Gainche from the CFMU is heading a cross Agency Team (of which I am a part) that looks into the corporate needs in support of mandating the mentioning of the aircraft registration on FPLs.

Since some years the CRCO takes particular interest in (and contributes whenever feasible towards) strategic development of “aircraft centric flight information systems”. Our own objective is to make use of (tap into) the additional “aircraft identity information” (aircraft registration marking/tail number and/or the ICAO 24-bit aircraft address) for the development of the route charges system, notably for improved quality of billing, enforced recovery and to enable differential (incentivised) charging,



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dependant upon aircraft specifics (avionics capabilities, pollution, noise, etc) - as provided for under emerging SES regulations.

In this context the CRCO has already prepared for making use of the following aircraft centric evolutions in respect of:

1. airport / ATM flight (plan) messages:

a. DPI-A (Departure planning information) message from CDM airports to CFMU, which provides for data fields for aircraft registration marking and/or the 24-bit aircraft address ;

b. FUM (Flight update message) from the CFMU to CDM airports, which provides for the data fields of aircraft registration marking and/or the 24-bit aircraft address ;

c. FPL for flights intending to make use of CPDLC, where mentioning of the 24-bit aircraft address will become mandatory for safety reasons;

d. FPLs in general: discussions are under way to establish to what extent the mentioning of the aircraft registration on all FPLs should be made mandatory for security (incl. SAFA) reasons and to allow for linking “gate to gate” ATM flight information systems with the “airborne to airborne flight information systems of airports (the knowledge of the aircraft identity in both systems would allow for linking them).

2. messages transmitted by aircraft avionics in :

a. passive mode for SUR purposes such as: • 24-bit aircraft address for Mode S radar the air or • 24-bit aircraft address for airport multilateration systems) or

b. active mode for SUR purposes such as: • 24-bit aircraft address for ADS-B in the air or on the ground • 24-bit aircraft address for CPDLC (LINK2000+) COM purposes

As at present the CRCO sources its flight related aircraft identity information as follows:

� For each chargeable flight a National Route Charges Office (RCO) will send the CRCO a “flight message”, the data fields of which might come from a single or multiple source: CFMU IFPS (FPL or RPL), airport MVT, ATC, etc

As at present 80% of flight messages contain the aircraft registration markings. Our object is to raise the coverage to 100% by tapping airport and avionics emitted 24-bit aircraft address info progressively becoming available.

We will use conversion tables between aircraft : serial number, registration markings and 24-bit aircraft address to use either to identify the unique airframe.

� For each flight the CFMU will send the IFPL to enable the CRCO to extract “route” information” needed to calculate the charges by State planned to be



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overflown. The CRCO has noticed that some 45% of these IFPLs are based upon RPLs and as such do not contain the aircraft registration markings. We have requested ANSPs which operate Mode S radar to capture the 24-bit aircraft address and to make it available to us through the CPRs (Correlated position reports) they already send to the CFMU today. In the future the same would apply for 24-bit aircraft addresses captured by ANSPs from ADS-B equipped aircraft in the air and on the ground.

� From eCODA, (sourced from ACARS of airline operational HQ’s) if available : i.e. aircraft registration markings

Selective Remarks:

The CRCO requirements are of course different from those of ABCD in terms of timing. We only require the flight data (such a s aircraft identity) some +/- 7 days after the date of flight (for billing purposes), whereas ABCD need them in advance and on-line (for ATM optimisation services / purposes).

Overall, I noticed that you only consider the aircraft registration marking (at FPL phase) in the ABCD, thus not availing of the progressive availability of the 24-bit aircraft address (both at FPL and operational phases) to uniquely identify an airframe. For implementations within the next 5 years the 24-bit aircraft address should probably be considered as an equally valid proxy for the aircraft identity / aircraft registration tracking purposes.

Personally, I would assume that the knowledge of the aircraft identity will become increasingly important – and necessary - for monitoring, fine-tuning / optimizing, controlling and even steering of ATM systems in conjunction with Airport systems. ABCD requirements and yields would both contribute towards and benefit from such an evolution.

abcd: aircraft based concept developments work package …...itinerary: station 0 corresponds to the...

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