FALBALA Final Project Report

Transcription

1 FALBALA Final Project Report First Assessment of the operational Limitations, Benefits & Applicability for a List of package I AS applications FALBALA Project Drafted by: Beatrice Raynaud Authorised by: Thierry Arino on ADDRESSEES: Francis Casaux (CARE/ASAS Manager), Mick Van Gool (CARE Manager), Bogdan Petricel (AGC Programme), Costas Tamvaclis (ADS Programme) COPY TO: CENA, DFS, EEC, NATS, UoG & Sofréavia Participants. EUROCONTROL CARE/ASAS/Sofréavia/ FALBALA Project Page 1/51

2 RECORD OF CHANGES Issue Date Detail of changes th May-2004 Document initialisation based on Project Progress Report dated April th June 2004 Refined sections 3, 4 and 6 based on WP1, WP2 and WP4 final report, respectively th June 2004 Minor changes in all sections following partners comments, draft material about WP3 in section 4 and proposed recommendations in section th July 2004 Changes in all sections following comments from EUROCONTROL and partners, additional material in section 5 following WP3 final report update, and additional material in section 7 about project conclusions and dissemination forum th July 2004 Proposed first issue IMPORTANT NOTE: ANY NEW VERSION SUPERSEDES THE PRECEDING VERSION, WHICH MUST BE DESTROYED OR CLEARLY MARKED ON THE FRONT PAGE WITH THE MENTION OBSOLETE VERSION EUROCONTROL CARE/ASAS/Sofréavia/ FALBALA Project Page 2/51

3 EXECUTIVE SUMMARY E.1. E.1.1. E.1.2. E.1.3. E.1.4. E.2. E.2.1. E.2.2. Project overview FALBALA stands for First Assessment of the operational Limitations, Benefits & Applicability for a List of package I AS applications. The project supported the validation of three selected Airborne Surveillance (AS) applications from Package I [1]: Enhanced Traffic Situational Awareness during flight operations (ATSA-AIRB), Enhanced Visual Separation on Approach (ATSA-VSA) 1, and Enhanced Sequencing and Merging operations (ASPA-S&M). It aimed at providing a better understanding of the current situation from both an airspace and an aircraft perspective through the analysis of European radar data recordings, and assessing the possible operational benefits brought by the AS applications under investigation. The FALBALA project was conducted by a consortium of six organisations (CENA, DFS, EEC, NATS, UoG, and Sofréavia as project leader). The contribution of three major European ANS Providers, as well as the participation of three major European airlines, significantly helped in the successful performance of the project. The project comes within the framework of the CARE/ASAS action. It is also of particular importance for the AGC and ADS Programmes and will support the EUROCONTROL CASCADE Programme charged with the validation / implementation of the applications included in Package I. Current situation analysis Airspace perspective From an overall airspace perspective, the assessment of the current situation was focused on three high-density environments of the European Core Area in which maximum operational benefits could be expected, i.e.: the Paris TMA, including both Paris Charles de Gaulle and Orly airports, the London TMA, including both London Heathrow and Gatwick airports, and the Frankfurt TMA. The analysis performed includes a qualitative assessment of the main arrival traffic characteristics observed within each TMA and Extended-TMA, as well as a quantitative assessment using representative operational indicators. This work took advantage from the preparatory radar data processing aimed at identifying typical arrival traffic patterns, as well as from the AIP and METAR information gathered to support the radar data processing and analysis. The analysis also benefited from the support of European ANS Provider representatives familiar with each environment. 1 This application was formerly named Enhanced Successive Visual Approaches (ATSA-SVA) within [1]. EUROCONTROL CARE/ASAS/Sofréavia/ FALBALA Project Page 3/51

4 E.2.3. E.2.4. The qualitative analysis dealt with the runway use, the use of radar vectoring to optimise the runway capacity while merging the arrival flows, the use of holding patterns to delay aircraft, the ordering of aircraft in the landing sequences and the spacing between successive aircraft in an arrival sequence. Some of the traffic characteristics were also addressed from a quantitative perspective. This was particularly the case for the spacing between aircraft in each arrival flow. Finally, specific traffic characteristics relevant to each investigated TMA were also assessed. These includes the aircraft spacing at the Initial Approach Fixes (IAF) for the traffic inbound to the Paris airports, the use of holding patterns by the traffic inbound to the London airports and the use of the Clearance limits within Frankfurt. This work provided a better understanding of the current situation within the Paris, London and Frankfurt TMAs. It has demonstrated that the arrival traffic patterns in the investigated TMAs are highly dependent on the ATC working practices developed to cope with the actual traffic demand and the airspace and airport constraints. In particular, different strategies seem to be applied for each airport of the three investigated TMAs to get maximum benefit from the available resources. E.2.5. Consequently, the operational indicators measured in each environment are not directly comparable. They need to be interpreted taking into account the characteristics of each airspace and airport (in particular, the available runways), as well as the strategic actions (e.g. ATC organisation, standard procedures) set up by ATC to manage the air traffic flows inbound and outbound of these airports. E.2.6. Finally, the analysis of the current situation, performed in the first phase of the FALBALA study, provided evidence that the applicability of the AS applications should be assessed in relationship with the current situation in each considered airspace taking into account their respective characteristics and constraints. E.3. E.3.1. E.3.2. E.3.3. Current situation analysis Aircraft perspective From an aircraft-centred perspective, the assessment of the current situation dealt with the description of the traffic environment as seen by both IFR and VFR flights in the three investigated TMAs, as well as the European Core Area en-route environment. The work combined both quantitative and qualitative assessments of what a pilot could see on a traffic display using traffic samples derived from the European radar data recordings and assuming full ADS-B equipage. The analysis dealt with the amount of the traffic information available in a given surveillance range and a given altitude band, and with the influence of various display modes. It addressed separately IFR and VFR operations, as well as the various phases of flight associated with the three ASAS applications under investigation. A specific analysis of the maximum number of surrounding traffic in the Northern Europe Area (i.e., apart from the Paris and London TMAs) was performed independently from the phase of flight. It should be underlined that the FALBALA project was not to assess or propose a particular CDTI design, but to bring elements for consideration by the future CDTI designers. These elements should also help defining required performances of an Airborne Surveillance and Data Processing system in the European airspace. EUROCONTROL CARE/ASAS/Sofréavia/ FALBALA Project Page 4/51

5 E.3.4. E.3.5. E.3.6. E.4. The study has demonstrated that the link between the airspace traffic density and the density of traffic information on the CDTI is not as direct as expected. Therefore, it is not possible to rely only on an airspace absolute perspective: a study based upon the relative perspective (counting aircraft observed by each aircraft of interest along their trajectory) seems essential. The study showed the sensitivity of the results to the quantity and the quality of the surveillance data used. The analysis of the maximum numbers of visible aircraft has also demonstrated the need for traffic filtering onboard the aircraft. For VFR flights, as the selected range values are small, a simple vertical filtering seems to be enough to allow for CDTI legibility. For IFR flights, a specific analysis would be required to determine if the required traffic filtering needs to be linked to the ASAS application or to the phase of flight. Indeed, the study already shows that a safetyoriented filter will be different from a situational awareness oriented filter. Finally, the study supports the idea that the ATSA-AIRB application is likely to bring safety benefits for VFR flights. Operational indicators, questionnaires and workshop E.4.1. Operational indicators were defined at the start of the study to drive both the assessment of the current situation and the extrapolation of potential benefits. This was mainly the case when analysing the European radar data recordings from both the airspace and the aircraft perspectives, although effort was focused on a few of them. When performing the operational assessment of the AS applications, the operational indicators were actually used as background information. E.4.2. This operational assessment was supported by the performance of operational interviews (through questionnaires) and an operational workshop. The purpose was to obtain expert opinion on the studied ASAS applications from operational representatives. There were eighteen questionnaire respondents from a mixture of operational staff, (pilots or controllers) and management staff (ATM & airline managers). The analysis shows some areas of strong common opinion, as well as some issues with very wide-ranging opinion. From the questionnaire responses, a set of key issues was identified for each of the three ASAS applications studied within FALBALA, which were used as starting points for the discussion at the workshop. The workshop itself was hosted by NATS at Heathrow Control Tower Building during March In all, twenty-six people attended the workshop. Topics of discussion included the operational applicability of each AS application, their technical requirements (e.g. level of onboard automation, use of intent information and required displayed information), as well as the nature of the operational benefits that can be expected. EUROCONTROL CARE/ASAS/Sofréavia/ FALBALA Project Page 5/51

6 E.4.3. For ASPA-S&M, it was felt that it would be highly feasible to implement the application in the Paris area, and even possible for London Gatwick. However it was considered unfeasible to implement such procedures for London Heathrow and Frankfurt due to the complexity of the airspace. The ASPA-S&M application was considered to increase efficiency due to the reduction in R/T and through more consistent aircraft spacing. It was uncertain whether the application would increase capacity. There was mixed opinion on the level of automation required, and the need for ADS-B intent data. As a consequence the impact of ASPA-S&M on pilot workload could not be determined. E.4.4. E.4.5. E.4.6. E.5. E.5.1. E.5.2. The applicability of the ATSA-VSA application within core European airspace appears to be very limited. For airports that do not currently use visual separation on approach, there is unlikely to be a case to introduce Enhanced Visual Separation. The additional benefits of the use of the CDTI for visual acquisition was that it would allow pilots to better judge spacing and might allow visually separated approaches to be used when VMC minima are not met but still with permanent visual contact. The ATSA-AIRB application was considered to give improved common situational awareness between pilot and ATC although it recognised that their perspectives of the traffic situation were different. It was felt there would be little affect on pilot or ATC workload. It was felt the largest benefit of the ATSA-AIRB application would be in remote airspace and not radar controlled airspace. There were also some issues identified which are common to all applications. It was recognised that there is a need to know what will be the minimum avionics requirements for ASAS, and what level of aircraft equipage needs to be reached before the anticipated benefits can be gained. The need for clear operational requirements and procedures for use of ASAS was restated and the issue of cost of retro-fitting aircraft avionics was raised. Assessment of possible operational benefits Finally, an initial assessment of possible operational applicability, limitations and benefits was performed which took advantages of: the analysis of real-time experiment outcomes, the analysis of the current situation performed from both the airspace perspective and the aircraft perspective, and the outcomes of the FALBALA operational interviews and workshop, as well as the operational expertise of the European ANS Providers participating in the project. For the ATSA-AIRB and ATSA-VSA applications, the results of the Cargo Airline Association s (CAA) Ohio Valley Operations Evaluation (OpEval) performed in July 1999 at Wilmington, Ohio and 2000 at Louisville, Kentucky were reviewed. EUROCONTROL CARE/ASAS/Sofréavia/ FALBALA Project Page 6/51

7 E.5.3. E.5.4. E.5.5. E.5.6. E.5.7. In summary, the study concluded that there are potentially many benefits of sharing traffic information with flight crew via a CDTI if the clutter and head down time issues can be resolved. One of the few potential disadvantages identified may be a tendency for pilots to question or hesitate over controller instructions, although this is difficult to anticipate for real operations. Further, it was highlighted that a CDTI could help in tasks such as visual acquisition, maintaining visual contact, gauging distance and closure rates during visual separation on approach. Therefore, it might be worthwhile to investigate why visual separation is so little used at major capacity-limited airports in Europe compared with the US. A specific approach was defined to address the ASPA-S&M application, which took advantage of the availability of the CoSpace real-time experiments conducted by EEC. It consisted of a comparison of the generic environment used in the experiments and the three specific environments (in conventional ATC ) described in the first step of the FALBALA study. Hence, a set of key characteristics for initial assessement of applicability of ASPA- S&M in TMA and E-TMA has been defined, and assessed against each specific environment with the support of the ANSP representatives participating to the FALBALA study. Finally, the framework proposed for the radar data extrapolation was illustrated using one metric, i.e. the aircraft spacing in the arrival sequences. However, the study highlighted that the assessment of benefits related to spacing at reference points was hardly feasible in the scope of the FALBALA study. To go a step further, it seems essential to determine the minimum applicable spacing for pairs of successive landings (e.g. considering wake vortex, runway type of operations, runway occupancy time) before benefit extrapolation. E.5.8. Although challenging, the assessment of operational benefits from a generic environment should be continued to develop the trends already identified. Further, since it is not easy to derive conclusive benefits from a generic environment, it is also necessary to assess the benefits using experiments on specific environment. E.6. E.6.1. Project results and dissemination In conclusion, the FALBALA study has demonstrated that: the airspace and airport characteristics and the traffic demand should be considered when assessing operational applicability and benefits of AS applications envisaged for implementation. the radar data analysis is of particular interest to better understand the current situation and assess possible benefits within specific airspace and at various airports. operational benefits depend on the AS application and the operational environment. EUROCONTROL CARE/ASAS/Sofréavia/ FALBALA Project Page 7/51

8 E.6.2. E.6.3. E.6.4. E.7. E.7.1. E.7.2. E.7.3. Key elements of the FALBALA study were presented to European stakeholders and representatives of the operational community during a one-day dissemination forum. The forum was held on the 8 th July 2004 in the premises of Eurocontrol Head- Quarters in Brussels. During this dissemination forum, the synthetic and combined descriptions of ATM operations at major European airports was well received. Further, the need to assess the applicability and possible benefits of future ASAS operations in the context of various airspace characteristics was recognised. Finally, although it was agreed that the conclusions of the FALBALA study should not be taken as definitive, it was mentioned that the initial assessment performed during the study using various sources (including not only feedback from operational experts, but also real-time simulation outcomes) allowed getting some confidence in the results. Project recommendations Based on the experience gained within the FALBALA study, it is recommended to enhance the evaluation process based on radar data extrapolation in order to support to the benefit assessment in relationship with specific European environments. Further in-depth analysis of the benefits identified for the ASPA-S&M and ASPA- AIRB applications should be performed, taking into account the potential limitations due to ASAS and CDTI design options. Such analysis could well be supported by a range of activities including: enhanced benefit evaluation based on radar data extrapolation, development of test and validation experiments in various operational environments, design studies of appropriate airborne traffic information and level of automation, assessment of the level of aircraft ADS-B/ASAS equipage necessary to deliver benefit and the cost of avionics retrofit, and benefit analysis in comparison with alternative operational improvements. With regard to the ATSA-VSA application, it is considered that an investigation of the differences in operations between United States and Europe, will support the assessment of the possible benefits. EUROCONTROL CARE/ASAS/Sofréavia/ FALBALA Project Page 8/51

9 TABLE OF CONTENTS 1. INTRODUCTION OBJECTIVE AND SCOPE BACKGROUD AND CONTEXT PROJECT OVERVIEW SCOPE AND PURPOSE PROJECT BREAKDOWN PROJECT PARTICIPANTS WP1 CURRENT SITUATION ANALYSIS AIRSPACE PERSPECTIVE GENERAL DATA GATHERING AND PROCESSING RADAR DATA ANALYSIS AND ASSESSMENT OF THE CURRENT SITUATION MAIN SIMILARITIES AND DISCREPANCIES MAIN ACHIEVEMENTS AND CONCLUSIONS WP2 CURRENT SITUATION ANALYSIS AIRCRAFT PERSPECTIVE GENERAL QUALITATIVE ASSESSMENT OF THE CURRENT SITUATION QUANTITATIVE ASSESSMENT OF THE CURRENT SITUATION MAIN ACHIEVEMENTS AND CONCLUSIONS WP4 OPERATIONAL INDICATORS, INTERVIEWS AND WORKSHOP GENERAL OPERATIONAL INDICATORS OPERATIONAL INTERVIEWS OPERATIONAL WORKSHOP MAIN ACHIEVEMENTS AND CONCLUSIONS WP3 ASSESSMENT OF POSSIBLE OPERATIONAL BENEFITS GENERAL ENHANCED TRAFFIC SITUATIONAL AWARENESS DURING FLIGHT OPERATIONS ENHANCED VISUAL SEPARATION ON APPROACH ENHANCED SEQUENCING AND MERGING WP5 PROJECT RESULTS AND DISSEMINATION SYNTHESIS OF RESULTS FINAL DISSEMINATION FORUM MAIN ACHIEVEMENTS AND CONCLUSIONS RECOMMENDATIONS FOR FUTURE WORK REFERENCES ACRONYMS...48 APPENDIX A: MAIN ISSUES DISCUSSED AT THE FALBALA DISSEMINATION FORUM...49 EUROCONTROL CARE/ASAS/Sofréavia/ FALBALA Project Page 9/51

10 LIST OF TABLES TABLE 1: DEFINITION OF THE THREE AS APPLICATIONS OF INTEREST TABLE 2: FLIGHT PHASES UNDER CONSIDERATION PER ASAS APPLICATION TABLE 3: PERSPECTIVES UNDER CONSIDERATION PER ASAS APPLICATION TABLE 4: AVERAGE AND MAXIMUM NUMBER OF VISIBLE AIRCRAFT PER PHASE OF FLIGHT IN (ARC, NORMAL) NAVIGATION DISPLAY MODE TABLE 5: RELATED OBJECTIVES OF OPERATIONAL INDICATORS TABLE 6: EXAMPLE OF A TYPICAL QUESTIONNAIRE ITEM TABLE 7: SUMMARY OF OPERATIONAL QUESTIONNAIRE RESPONDENTS TABLE 8: SUMMARY OF RESULTS FOR THE ATSA-AIRB APPLICATION TABLE 9: SUMMARY OF RESULTS FOR THE ATSA-VSA APPLICATION TABLE 10: SUMMARY OF RESULTS FOR THE ASPA-S&M APPLICATION LIST OF FIGURES FIGURE 1: ILLUSTRATION OF ARRIVAL TRAFFIC PATTERNS AT PARIS, LONDON AND FRANKFURT FIGURE 2: ILLUSTRATION OF ARRIVAL SPACING DISTRIBUTION AT PARIS, LONDON AND FRANKFURT FIGURE 3: ILLUSTRATION OF COCKPIT TRAFFIC DISPLAYS AT PARIS, LONDON AND FRANKFURT FIGURE 4: MAXIMUM NUMBER OF DISPLAYED TRAFFIC ON BOARD CRUISING IFR FLIGHTS IN (ARC, NORMAL, 80NM) NAVIGATION DISPLAY MODE FIGURE 5: MAXIMUM NUMBER OF VISIBLE AIRCRAFT IN NORTHERN EUROPE FIGURE 6: ISSUES RELATED TO THE BENEFITS EXTRAPOLATION EUROCONTROL CARE/ASAS/Sofréavia/ FALBALA Project Page 10/51

11 1. Introduction 1.1. Objective and scope This report presents the objectives and outcomes of the FALBALA project: FALBALA stands for First Assessment of the operational Limitations, Benefits & Applicability for a List of package I AS applications The project lasted one year, from mid-july 2003 to mid-july Its first phase consisted of setting the foundations for a first assessment of the operational applicability and the benefits associated with some Airborne Surveillance (AS) applications included in Package I [1]. The second phase of the project consisted of getting feedback from the operations experts on, and performing an initial assessment of, the operational benefits and constraints related to the ASAS 2 applications under investigation The project comes within the framework of the CARE/ASAS action. The main purpose of the CARE/ASAS action is to support the validation of a strategic line of action identified by the ATM2000+ strategy, in particular by establishing a common view of ASAS applications. The main issues include the feasibility and conditions of applicability of the concept The project is also of particular importance for the EUROCONTROL CASCADE Programme in charge of the validation / implementation of the applications included in Package I. The results of the project will contribute to the validation activity of Package I and to future Cost / Benefit Analysis work Backgroud and context The use of ASAS is seen as a promising option in the future ATM concept to provide an increase in capacity and flight efficiency while enhancing flight safety. By exploiting advances in flight deck technologies, ASAS applications aim is to increase the flight deck s involvement in the maintenance of a safe, orderly and efficient flow of air traffic As for any new ATM concept, the evolution to a mature ASAS environment must be conducted via a phased implementation. At all stages of this phased implementation, compatibility must be assured between current and future systems and procedures. In addition, potential benefits must be assessed to encourage aircraft equipage and operational use of ASAS applications The agreed packaging approach aims at the early implementation of some ASAS applications on a worldwide basis. Package I of GS/AS applications [1] is going to help focusing the energies required for the development of the appropriate operational / technical standards and equipment. 2 The Airborne Separation Assistance System (ASAS) is considered a major enabler of airborne Package I applications. Hence, AS and ASAS EUROCONTROL CARE/ASAS/Sofréavia/ FALBALA Project Page 11/51

12 2. Project overview 2.1. Scope and purpose The FALBALA project supported the validation of three selected Airborne Surveillance applications from Package I: Enhanced Traffic Situational Awareness during flight operations (ATSA-AIRB); Enhanced Visual Separation on Approach (ATSA-VSA), formerly named 3 Enhanced Successive Visual Approaches (ATS-SVA); and Enhanced Sequencing and Merging operations (ASPA-S&M) As a reminder, the Package I definition [1] of the three AS applications of interest is provided in the following table: AS application Enhanced traffic situational awareness during flight operations (ATSA-AIRB) Enhanced successive visual approaches (ATSA-SVA) Enhanced sequencing and merging operations (ASPA-S&M) Short description This application provides the flight crews with an enhanced traffic situational awareness irrespective of visual conditions. Additional data is provided to flight crews to supplement traffic information provided either by controllers or other flight crews. The objectives are to improve safety of flight and the efficiency of air traffic control. In all airspace, the flight crews will be better able to detect an unsafe situation. This application is an aid for the flight crews to perform successive visual approaches when they are responsible for maintaining visual separation from the aircraft they are following. The objectives are to perform successive visual approach procedures on a more regular basis to enhance the runway throughput, and to conduct safer operations especially in high-density areas. The objective is to redistribute tasks related to sequencing (e.g. in-trail following) and merging of traffic between the controllers and the flight crews. The controllers will be provided with a new set of instructions directing, for example, the flight crews to establish and to maintain a given time or distance from a designated aircraft. The flight crews will perform these new tasks using a suitable human-machine interface. The main expected benefit is increased controller availability, but increased capacity through better adherence to ATC separation minima is also expected especially in high-density areas. Table 1: Definition of the three AS applications of interest Depending on the ASAS application under investigation, the following flight phases were considered: AS application Flight phases Take-off Climb Cruise Descent Approach Final ATSA-AIRB X X X X X X ATSA-VSA ASPA-S&M X X X Table 2: Flight phases under consideration per ASAS application X 3 The Requirement Focus Group (RFG), in charge of the Package I harmonisation between US and Europe, recently agreed this renaminig to avoid any misunderstanding between visual separation and visual approach. EUROCONTROL CARE/ASAS/Sofréavia/ FALBALA Project Page 12/51

13 The assessment performed within the project considered two distinct perspectives: an airspace perspective: this perspective addresses traffic synchronisation aspects, i.e., the tactical establishment and maintenance of a safe, orderly and efficient flow of air traffic. This perspective encompasses the regulatory authority, the ANS provider and the aircraft operator perspectives; and an aircraft perspective: this perspective addresses airborne surveillance and traffic situational awareness aspects. This perspective is own aircraft-centred and it encompasses the flight crew perspective for both IFR and VFR flights. AS application Airspace perspective Aircraft perspective IFR VFR ATSA-AIRB X X ATSA-VSA X X ASPA-S&M X X Table 3: Perspectives under consideration per ASAS application The project was based on sound and validated data. Hence, it aimed at: providing a better understanding of current situation through the analysis of European radar data recordings. From an airspace perspective, consideration was on three high-density environments of the European Core Area in which maximum operational benefits could be expected, i.e.: the Paris TMA, the London TMA, and the Frankfurt TMA; From an aircraft perspective, the European Core Area en-route environment, comprising France, Germany, UK and Maastricht en-route airspace was also considered. assessing the possible operational benefits brought by the AS applications under investigation; Both qualitative and quantitative assessments of the circumstances, in which, and the frequencies, with which, the applications can be used, and the operational benefits that would accrue, has been initiated Project breakdown The work programme carried out within the project was organised into Work Packages (WP) with clearly defined objectives and deliverables [2]: WP1: Current situation analysis Airspace perspective (Cf. section 3); This analysis was focused on the arrival traffic patterns identified within European radar data recordings gathered at the start of the project. WP2: Current situation analysis Aircraft perspective (Cf. section 4); This analysis was focused on the characteristics, and possible limitations, of the enhanced traffic information as possibly displayed in the cockpit of both IFR and VFR flights within typical arrival and en-route traffic situations. EUROCONTROL CARE/ASAS/Sofréavia/ FALBALA Project Page 13/51

14 WP3: Assessment of possible operational benefits (Cf. section 6); This WP consisted of the analysis of the outcomes of existing relevant ASAS real-time simulations, and the comparative analysis between the current (as described in WP1 and WP2) and the future situations taking into account the WP4 outcomes about possible operational benefits. WP4: Operational interviews and workshop (Cf. section 5); This WP first consisted of defining a set of operational indicators for use within the project. In a second phase, it consisted of the performance of ATC controller and pilot interviews, and in the organisation of an operational workshop, to get a better understanding of the operational benefits and constraints related to the three ASAS applications under investigation. WP5: Project management and results dissemination (Cf. section 7); This WP consisted of the management of the FALBALA project and ensured a close co-ordination of the work between the project participants. It also consisted of the consolidation and the dissemination of the results obtained in the previous Work Packages The FALBALA project was composed of two main phases: Phase 1 (current situation) consisted in providing the foundations of the project by gathering and processing the radar data, by adapting the tools and by defining the metrics required for the successful performance of the project. The analysis of the current situation both for an airspace perspective and an aircraft perspective was part of this phase. It was mainly composed of WP1, WP2 and WP4; Phase 2 (extrapolation) provided a first assessment of the operational benefits of the three AS applications investigated. It also aimed at extrapolating the results of the current situation analysis and providing an assessment of possible operational improvements. It concluded in synthesising the work performed during the project, in developing a final report and organising a dissemination forum. It was mainly composed of WP3, WP4 and WP WP4, which belonged to both phases, defined the operational indicators that supported the analysis of the current and future situation, and was supported by the operational workshop aiming at getting the operational community feedback for both pilot and ATC controller perspectives Project participants The FALBALA study was conducted by a consortium of six organisations (CENA, DFS, EEC, NATS, UoG and Sofréavia) with a leading role for Sofréavia (ATM division, AAA skill unit). A dedicated Task Leader was identified for each work package. The approach taken and the nature of the work entailed a close coordination between the project participants and with the CARE/ASAS Manager In addition, three major European airlines, i.e. Air France, British Airways and Lufthansa also participated to the operational interviews and workshop aiming at getting their operational feedback during the performance of the project. EUROCONTROL CARE/ASAS/Sofréavia/ FALBALA Project Page 14/51

15 3. WP1 Current situation analysis Airspace perspective 3.1. General Within WP1, focus has been on analysing the arrival traffic patterns identified within European radar data recordings gathered at the start of the project. This analysis includes a qualitative assessment of the main traffic characteristics observed within each TMA and Extended-TMA, as well as a quantitative assessment using representative operational indicators The WP1 final report [3] first describes the methodology and tools that supported the assessment of the current situation performed using European radar data recordings. It provides an overview of the arrival traffic patterns observed in each Extended-TMA, each TMA and at the major airports. It also presents the main similarities and discrepancies identified between the three investigated airspace Finally, it draws some general conclusions on the work performed and provides recommendations for future work. In particular, it is expected that assessment of the current situation performed in WP1 will help assessing the applicability of the investigated ASAS applications within the various considered airspace Data gathering and processing The preliminary task conducted within WP1 consisted of the gathering of one month of radar data from the European Core Area. Relevant information that supported the analysis of the radar data recordings (e.g. associated METAR data and AIP data from each airspace) was also collected. This was ensured through the implication within the project of three major European ANS Providers and of EEC The gathered radar data were from various sources (i.e. Mono-pulse SSR, Radar Data Processing Systems and Mode S station). Initial radar data processing, common to all environments, was applied to get radar data in a common standard format (i.e. MADREC format) and to discard irrelevant tracks for the purpose of the FALBALA study. It should be noted that FALBALA is the first project dealing with the processing of such a significant amount of radar data for different environments and for the same period To support the identification of the relevant traffic patterns within the radar data recordings, further radar data processing was performed to extract and classify the tracks taking into account the airspace characteristics, i.e. the airports, the runways and the arrival procedures. In a nutshell, an innovative approach has been developed that consisted in associating a radar track to published procedure, the procedures being initially described using the ARINC 424 semantic in an XML format. EUROCONTROL CARE/ASAS/Sofréavia/ FALBALA Project Page 15/51

16 3.3. Radar data analysis and assessment of the current situation The core work conducted in WP1 consisted of analysing the arrival traffic patterns extracted from the European radar data recordings for each of the three TMA under investigation, i.e. Paris, London and Frankfurt TMA. This analysis benefited from the support of European ANS Provider representatives familiar with each environment The analysis of the current situation included a qualitative assessment of the main traffic characteristics observed within each TMA and Extended-TMA (E-TMA), as well as a quantitative assessment using representative operational indicators. This work took advantage from the radar data processing performed previously, as well as from the AIP and METAR information gathered to support the radar data processing and analysis Separate and detailed analysis was made for each major airport, i.e. Paris Charles de Gaulle, Paris Orly, London Heathrow, London Gatwick and Frankfurt. The result of these analyses is described into three separate annexes of the WP1 final report [3], respectively for the Paris, London and Frankfurt TMA The analyses dealt with the runway use, the use of radar vectoring to optimise the runway capacity while merging the arrival flows, the use of holding patterns to delay aircraft, the ordering of aircraft in the landing sequences and the spacing between successive aircraft in an arrival sequence. This preliminary work was mainly focused on the understanding of each airspace structure, the local traffic demand and ATC practices used to handle traffic flows in the considered airspace The following figures illustrate arrival traffic patterns observed within the three TMAs under investigation, during a westerly landing configuration. These snapshots give an overview of the approach and final phases in the three major airports in Europe. Paris (Charles De Gaulle) London (Heathrow) Radar vectoring area EUROCONTROL CARE/ASAS/Sofréavia/ FALBALA Project Page 16/51

17 Frankfurt Figure 1: Illustration of arrival traffic patterns at Paris, London and Frankfurt In a second step, some of the traffic characteristics were also addressed from a quantitative perspective, i.e. with the computation of operational indicators over the period of radar data recordings used for the study or on selected days. This is particularly the case for the spacing between aircraft in each arrival flow (as illustrated in the following figures). Paris CDG - Two pairs of parallel runways < L 26R 27L 27R (s) Specialised runways in the south for either landings or departures, and alternatively used runways in the north for both landings and departures London Heathrow - Two parallel runways 27L 27R Specialised runways for landings, swapped at around 3 pm for environmental reasons < (s) EUROCONTROL CARE/ASAS/Sofréavia/ FALBALA Project Page 17/51

18 Frankfurt - Dependent parallel runways 07L 07R Dependent runways used for both landings and departures < (s) Figure 2: Illustration of arrival spacing distribution at Paris, London and Frankfurt Specific traffic characteristics relevant to each investigated TMA were also assessed. These includes the aircraft spacing at the Initial Approach Fixes (IAF) for the traffic inbound to the Paris airports, the use of holding patterns by the traffic inbound to the London airports and the use of the Clearance limits within Frankfurt Main similarities and discrepancies Different strategies seem to be applied for each airport of the three investigated TMAs to get maximum benefit from the available resources. The main similarities and discrepancies between the three environments identified during the study include the following: The similar definition of a Terminal Control Area (i.e., a TMA) around the major airports with three or four main TMA entry points (which correspond to the initial fixes for arrival procedures), but the distinct airspace characteristics at each airport of the considered TMAs: small terminal airspace around the London airports with IAFs close to the runways; two runways at Heathrow and only one runway in Gatwick. medium terminal airspace around the Frankfurt airport; two dependent parallel runways and a third one with distinct orientation at the airport. large terminal airspace around the Paris major airports with remote IAFs; Triple parallel approaches with some shared IAFs between airports; two set of close parallel runways at Paris CDG and two converging runways at Paris Orly. The similar use of direct routing in E-TMA to expedite arrival flights converging towards same IAF (when traffic density permits) and the same limited use of the Standard Arrival Routes (STAR), but the distinct use of approach procedures in TMA depending on ATC working practices: no published approach procedures in London Radar Vectoring area; use of initial approach procedures, followed by radar vectoring towards final approach procedures, in Paris; use of RNAV procedures in Frankfurt including radar vectoring for integration on final approach. EUROCONTROL CARE/ASAS/Sofréavia/ FALBALA Project Page 18/51

19 The existence of two, three or four distinct IAFs for major arrival flows towards distinct airports in London and Paris TMA (a part from a few exceptions), but the distinct operational use of the IAFs towards each airport depending on their proximity from the runway thresholds and the ATC working practices. The same definition of holding patterns typically at the IAF (or Clearance Limit in Frankfurt), but the distinct use of holding patterns depending on ATC practices, actual traffic demand and airspace constraints: not typically used in Paris CDG and London Gatwick; sometimes used in Paris Orly and Frankfurt; typically used in London Heathrow. The similar use of radar vectoring to either expedite or delay the flights when building arrival sequences in E-TMA and when merging one or more arrival flows in both E-TMA and TMA, as well as the early radar vectoring similarly applied before the IAF in TMA (depending on the IAF proximity from the final approach axis), but the distinct traffic patterns observed in TMA depending on the airspace available and the applicable procedures: S-shaped traffic patterns in London (for merging of arrival flights on final approach); Trombone -like traffic patterns in Frankfurt (with long downwind legs of RNAV procedures); combination of large trombone and comb -like traffic patterns in Paris (with pseudo-downwind legs and vectors towards base legs or final approach axis). The distinct use of the runways depending on the airport characteristics and constraints: specialised runway for either landings or take-offs in London Heathrow, Paris Orly and Paris CDG south, and for departures only in Frankfurt; runway used for both landings and take-offs in London Gatwick, Paris CDG north and Frankfurt parallel runways; triple parallel approaches in Paris CDG approach (due Le Bourget proximity); staggered landings on closed parallel runways in Frankfurt. The significant variations observed in the three TMAs with regard to the aircraft spacing between arrival flights depending on the runway use, the traffic demand (with more or less pressure on the landing runway) and the type of aircraft (and applicable Wake Vortex minima) Main achievements and conclusions The work conducted within WP1 provided a better understanding of the current situation within the Paris, London and Frankfurt TMAs. It has demonstrated that the arrival traffic patterns in the investigated TMAs are highly dependent on the ATC working practices and supporting tools developed to cope with the actual traffic demand and the airspace and airport constraints. EUROCONTROL CARE/ASAS/Sofréavia/ FALBALA Project Page 19/51

20 Consequently, the operational indicators measured in each environment are not directly comparable. They need to be interpreted taking into account the characteristics of each airspace and airport (in particular, the available runways), as well as the strategic actions (e.g. ATC organisation, standard procedures) set up by ATC to manage the air traffic flows inbound and outbound these airports. Main conclusions and results The analysis of the current situation performed within WP1 has concluded that: the airspace and airport characteristics and the actual traffic demand must be considered carefully when assessing the traffic patterns resulting from ATC practices, a more in-depth investigation of the current situation should be performed to better support the quantitative assessment of the possible benefits brought by any AS application, and the applicability of the AS applications envisaged for early implementation in Europe should be assessed in relationship with the current situation in each airspace taking into account their respective characteristics and constraints. Hence, the analysis of the traffic patterns identified through the European radar data recordings should support the assessment of the operational applicability and the possible benefits brought by the AS applications under investigation. Recommendations for future work To get a more complete and detailed picture of the current situation, it could be envisaged that future work addresses the following items: the current situation to other major TMAs in Europe to identify any other traffic patterns resulting from different ATC methods; the consideration of additional data (like flight plan data with the actual aircraft type) in relationship with the European radar data recordings, in particular to correlate between the actual aircraft spacing and the radar wake vortex separation minima, the actual vertical profiles to assess the operational use of vertical separation between arrival flights converging towards the same merging point, the actual speed profiles to assess the actual use of speed control to establish and maintain the arrival sequences, and to correlate it to the vertical profiles, the interference between arrival and departure flights to assess the constraints that apply to the arrival and departure flows, and the relationship between the traffic density and complexity, and the actual aircraft spacing in the arrival sequences Finally, to support a detailed quantitative assessment of possible benefits brought by the AS applications, additional statistics could be performed on: the heading and speed changes during the establishment and maintenance of arrival flows of traffic, and the flight distance and duration during the descent, approach and final phases of flight could be assessed. EUROCONTROL CARE/ASAS/Sofréavia/ FALBALA Project Page 20/51

21 4. WP2 Current situation analysis Aircraft perspective 4.1. General The assessment of the current situation performed within WP2 provided a description of the traffic environment as seen by both IFR and VFR flights in the three environments assessed in WP1, as well as in the en-route environment of core Europe. This work benefited from the European radar data processing performed in WP1, as well as from the AIP and METAR information gathered (cf. section 3.2) The WP2 final report [4] combines both the quantitative and qualitative assessment, from an aircraft perspective, of the cockpit display of traffic information derived from the European radar data recordings. This work is expected to help define the required performance of an Airborne Surveillance and Data Processing system in European airspace Finally, WP2 also developed some AVI format films of CDTI animations, which supported discussions during the operational workshop (cf. section 5.2.2) about the possible benefits and constraints linked to the provision of airborne traffic information Qualitative assessment of the current situation Initial work conducted within WP2 consisted in analysing what a pilot could see on a traffic display fed with traffic samples from the three TMAs under investigation. This initial analysis was mainly a qualitative assessment of the main airborne traffic information characteristics during typical scenarios. It addressed separately IFR and VFR operations, as well as the various phases of flight associated with the three ASAS applications under investigation This analysis used cockpit display facilities developed at CENA. These include an EFIS (Electronic Flight Information System) Control Panel, a Navigation Display (ND) combined with a Cockpit Display of Traffic Information (CDTI), and a Primary Flight Display, which can be customised to assess various display options like the Navigation Display mode, traffic display range, altitude band or symbology The following figures illustrate some typical scenarios analysed during the study. Various display modes (i.e. Rose and Arc modes), traffic display ranges and altitude bands are presented. EUROCONTROL CARE/ASAS/Sofréavia/ FALBALA Project Page 21/51

22 VFR traffic information at a GA airfield IFR holding pattern in London TMA IFR Sequencing & Merging in Paris TMA IFR on RNAV procedure in Frankfurt TMA Figure 3: Illustration of cockpit traffic displays at Paris, London and Frankfurt It should be underlined that the FALBALA project was not assessing or proposing a particular CDTI design, but that it brought elements to be considered by the future CDTI designers Quantitative assessment of the current situation The next step within WP2 consisted in performing a quantitative assessment of airborne traffic information characteristics seen on a cockpit display of both IFR and VFR flights in different phases of flight and different environments. In particular, distinct analysis was performed for IFR flights: in cruise phase of flight, along STARs towards Paris and London airports, along RNAV procedures towards Frankfurt airport, during initial approaches in Paris and along final approaches at major airports. EUROCONTROL CARE/ASAS/Sofréavia/ FALBALA Project Page 22/51

23 The amount of the traffic information available in a given surveillance range and a given altitude band have been analysed. Two methods of aggregation have been used to get statistics over samples of radar data recordings: the first one was based on the curvilinear abscises along the procedure followed by the aircraft of interest. This determined the quantity of traffic that could be seen by an aircraft of interest along a given procedure and depending on the curvilinear distance to a given fix. another one was based on the geographical position of the aircraft of interest and the split of the airspace into squares whose size depended on the considered phase of flight. This gave the number of traffic that could be seen by an aircraft of interest in this square during the amount of time that was processed The influence of the various display modes of this traffic information was evaluated using several days of radar data recordings. The results highlighted the need for specific traffic filtering, possibly depending on the phases of flight, to support enhanced traffic situational awareness during flight operations The following figure illustrates the maximum number of traffic displayed onboard an IFR flight in cruise phase, depending on its geographical position inside the European core area. The selected ND mode is Arc, with a 80 NM range and the normal TCAS relative altitude band, i.e. from 2700 feet to feet. These display options are the actual selections used for navigation purposes. Figure 4: Maximum number of displayed traffic on board cruising IFR flights in (Arc, Normal, 80NM) navigation display mode EUROCONTROL CARE/ASAS/Sofréavia/ FALBALA Project Page 23/51

24 Using Maastricht radar data recordings, a specific analysis of the maximum number of surrounding traffic in the Northern Europe Area (i.e., apart from the Paris and London TMAs) was performed independently from the phase of flight, to help set up the maximum surveillance tracking requirements for an airborne surveillance system This graph shows the evolution of the maximum number of visible traffic in relation with the selected range. All the surrounding traffic (in the radar coverage) is taken in account for the aircraft of interest and the ranges are extended up to the maximum range actually used for the Navigation Display. Figure 5: Maximum number of visible aircraft in Northern Europe To set up the maximum surveillance requirements, only the Rose mode without any vertical selection (dark blue curve) is relevant. This curve does not follow the square progression of the radius. The maximum number is not directly linked with the covered surface. An almost linear extrapolation seems to be preferable to assess the maximum number of targets with higher range (y x + 1.2x + 0.7) Actually, with the additional use of Gatwick and Paris-North radar data which cover the two most crowded TMAs, the analysis of the maximum targets for IFR flights in cruise phase shows a higher number of visible aircraft for ranges up to 80 NM than that measured with the Maastricht radar data alone. However, due to the two radar coverage limitations, it is not possible to assess this maximum number for ranges up to 160 NM as it is in the case of the Maastricht radar data The following table provides a synthesis of the average and maximum number of aircraft visible (obtained with an aggregation based on the geographical position of the own aircraft) to an aircraft in a specific phase of flight with a selected altitude filter of Normal ([-2700 ft; ft]), in Arc mode. Similar synthesis is also provided in the WP2 final report [4] for the Rose mode. EUROCONTROL CARE/ASAS/Sofréavia/ FALBALA Project Page 24/51