Evolution of the Surveillance Infrastructure

Transcription

1 Evolution of the Surveillance Infrastructure Document information Project title Surveillance Infrastructure Rationalisation Project N Project Manager THALES Deliverable Evolution of the Surveillance Infrastructure Name Deliverable ID D10-02 Edition Template version Task contributors DFS, EUROCONTROL, THALES Please complete the advanced properties of the document Abstract This paper forms part 2 of the final deliverable of the WP project. This report summarises the drivers for change that are foreseen to influence the European surveillance infrastructure and proposes a roadmap of how the changes will influence the evolution of the infrastructure. The roadmap can be used as a contributor when considering means for rationalisation of an ANSPs surveillance infrastructure or when assessing the surveillance specific aspects of higher-level strategic documents such as the European ATM Master Plan and the Strategic Guidance in Support of the Execution of the ATM Master Plan and for compiling an ANSPs local surveillance plans.

2 Authoring & Approval Prepared By Name & company Position / Title Date Andrew Desmond-Kennedy / EUROCONTROL Project Member 19/10/2012 Reviewed By Name & company Position / Title Date Philippe Juge / THALES Project Manager 29/10/2012 Daniel Muller / THALES Project Member 29/10/2012 Thomas Oster / EUROCONTROL Project Member 29/10/2012 Christos Rekkas / EUROCONTROL Project Member 29/10/2012 Michel Borely / EUROCONTROL Project Member 29/10/2012 Marcel Sobottka / DFS Project Member 29/10/2012 Roland Mallwitz / DFS Project Member 29/10/2012 Andreas Herber / DFS Project Member 29/10/2012 Approved By Name & company Position / Title Date Philippe Juge / THALES Project Manager 29/10/2012 Andrew Desmond Kennedy / EUROCONTROL Project Member 29/10/2012 Marcel Sobottka / DFS Project Member 29/10/2012 Document History Edition Date Status Author Justification /10/2012 New Document IPR (foreground) This deliverable consists of SJU foreground. SESAR JOINT UNDERTAKING, Created by [Member(s)] for the SESAR Joint Undertaking within the frame of the SESAR Programme co-financed by the EU and EUROCONTROL. The opinions expressed herein reflects the author s view only. The SESAR Joint Undertaking is not liable for the use of any of the information included herein. Reprint with approval of publisher and with reference to source code only. SESAR Joint Undertaking Point of Contact For further details regarding the SESAR Programme please visit or for specific information regarding the WP please contact: info@sesarju.eu (Please ensure that the subject field of the mail contains the message: Query Regarding WP ) 2 of 70

3 Table of Contents EXECUTIVE SUMMARY INTRODUCTION PURPOSE OF THIS PROJECT PURPOSE AND SCOPE OF THIS DELIVERABLE INTENDED READERSHIP INPUTS FROM OTHER PROJECTS ACRONYMS AND TERMINOLOGY INFLUENCES ON THE EVOLUTION OF EUROPEAN SURVEILLANCE OPERATIONAL ENVIRONMENT AND DRIVERS FOR CHANGE General Operational Environment RF Environment ATC Controller Efficiencies Composition of the Aircraft Fleet Legislation AVIONICS SUPPORTING SURVEILLANCE Equipage Requirements DEVELOPMENT STATUS OF SURVEILLANCE TECHNIQUES General Independent Cooperative Surveillance Techniques Dependent Cooperative Surveillance Techniques Independent Non-Cooperative Surveillance Ground Data Fusion DEPLOYMENT STATUS OF THE SURVEILLANCE INFRASTRUCTURE The Current European Surveillance Infrastructure ROADMAP TO THE SURVEILLANCE INFRASTRUCTURE OF TARGET STATE DESCRIPTION Principal Differences between the Current and Future Scenarios for Surveillance PHASE 1 OF THE ROADMAP - TODAY TO Description of the Phase 1 Surveillance Infrastructure Surveillance Coverage PHASE 2 OF THE ROADMAP TO Description of the Phase 2 Surveillance Infrastructure Surveillance Coverage ROADMAP IN GRAPHICAL FORM Airborne surveillance by ground Aircraft-Aircraft Surveillance SUMMARY OF TASKS IDENTIFIED AS NECESSARY TO SUPPORT THE TRANSITION TO THE TARGET STATE IDENTIFIED WORK AREAS Support the Development of ADS-B In Applications Support the Provision of Additional ADDs from an Aircraft: /1090 Spectrum Activities Investigate and Develop Means to Provide Oceanic or Remote Region Surveillance Enable ADS-B Equipage on ALL Aircraft Maintain the Surveillance Infrastructure Support the Development of MSPSR Products and Associated Standards CHANGES TO THE SESAR MASTERPLAN AND THE SUPPORTING GUIDANCE DOCUMENT SESAR ATM MASTERPLAN SUBJECTS FOR INCLUSION IN THE SESAR ATM MASTERPLAN STRATEGIC GUIDANCE IN SUPPORT OF THE EUROPEAN ATM MASTER PLAN of 70

4 6 CONCLUSIONS REFERENCED DOCUMENTS...58 APPENDIX A ACRONYMS AND TERMINOLOGY...60 APPENDIX B DEFINITIONS...64 B.1 SURVEILLANCE TERMS...64 B.2 MISCELLANEOUS TERMS of 70

5 List of tables Table 1: Key Dates Contained in Published European Commission Implementing Regulations...19 Table 2: Summary of Independent Cooperative Surveillance Technique Availability...23 Table 3: Summary of Dependent Cooperative Surveillance Technique Availability...25 Table 4: Summary of Independent Non-Cooperative Surveillance Technique Availability...28 Table 5: Secondary surveillance radars (Mode A/C) installations...31 Table 6: Secondary surveillance radar (Mode S) installations...32 Table 7: Operational Improvements Placing Requirements Upon Surveillance...54 Table 8: Categories of air traffic surveillance sensors...66 List of figures Figure 1: Long Term Trend in European IFR Air Traffic (Source: Eurocontrol)...13 Figure 2: Predicted traffic in Figure 3: Airborne surveillance by ground...47 Figure 4: Aircraft to Aircraft Surveillance...48 Figure 5: Aeronautical surveillance system...65 List of Standalone Appendices The information presented in the two tables that form the following appendices is too condensed to be viewed in A4. Consequently they are provided in a standalone form. Appendix C: Correlation between Operational Improvements, Enablers and ADS-B Functionality Appendix D: Correlation between Operational Improvements, Enablers and Further Surveillance Developments to Support the Future ATM Infrastructure 5 of 70

6 Executive summary This report describes drivers for change and how the surveillance infrastructure is foreseen to evolve over the next 20 years. The objective of the surveillance infrastructure is to provide the required surveillance functionality and performance to enable a safe, efficient and cost-effective Air Traffic Management service. The current surveillance infrastructure is mainly composed of mono-pulse and sliding window (Mode A/C) Secondary Surveillance Radar (SSR), SSR Mode-S and Primary Surveillance Radars (PSRs). Recently, however, technological developments such as Automatic Dependent Surveillance Broadcast (ADS-B) and Wide-Area Multilateration (WAM) have reached maturity and are being deployed across Europe. Emerging technologies such as Multi-Static PSR (MSPSR) and Hybrid Surveillance (ACAS using ADS-B message content) have demonstrated their feasibility and once developed, validated and deployed can influence the future surveillance infrastructure. In parallel, new performance targets and associated operational requirements are emerging from Single European Sky and SESAR initiatives. These factors will drive changes to the existing surveillance infrastructure. This evolution needs to be managed, for it will also be influenced by an extensive range of other factors such as global interoperability, civil-military coordination, the introduction of functional airspace blocks (FABs), and changes to the composition of the aircraft fleet with the introduction of very light jets and unmanned aircraft. Furthermore, cost and radio frequency spectrum efficiency considerations will lead to a rationalisation of the current infrastructure, in which legacy systems will be phased out as soon as practicable and new, more efficient technologies will be introduced. Surveillance systems are a key enabler of the SESAR future operational concept. They are expected to be leaner and more efficient in the future achieving safety and service continuity objectives by combining a layer of ADS-B with a layer of secondary surveillance (provided either by SSR Mode S or WAM). Primary radar coverage will also be available, where required (e.g. for safety or security reasons), either by classic (mono-static) PSR or possibly in the form of multi-static PSR (MSPSR). In addition to ground-based surveillance, ADS-B will also enable the development of new airborne surveillance operational services including air traffic situational awareness, spacing, separation and self-separation. Subject to design, validation and the establishment of a positive business case it is also possible that an aircrafts ADS-B transmissions could be relayed to the ground via satellite. This could, if considered necessary, provide improved surveillance in Oceanic and Remote areas. To achieve these changes, the avionics carried on board an aircraft must become a fully integrated element of the surveillance infrastructure. The scope of surveillance systems will extend to embrace an increasingly diverse range of avionic components such as GNSS, traffic computers and cockpit display systems, as well as the transponders. The activities conducted in recent years have established a solid foundation which allows the European surveillance infrastructure to meet future needs and upon which SESAR can build. 6 of 70

7 1 Introduction 1.1 Purpose of this Project In recognition that the future surveillance infrastructure is to be leaner and more efficient in respect of a number of key performance indicators a key objective of the project was to detail a methodology that promotes a rationalisation and adaptation to the Surveillance Infrastructure. (See Ref Doc 1) A secondary objective of this project was to develop a roadmap, this document, to support a transition to the future Surveillance Infrastructure as envisaged in the ATM Masterplan (Ref Doc 2). The roadmap or strategy is to exploit the benefits that new and emerging surveillance techniques can bring whilst taking due cognisance of its context within the evolution of the wider Civil/Military ATM Infrastructure. 1.2 Purpose and Scope of this Deliverable The purpose of this document is to provide a general, high-level description of the current European surveillance infrastructure, the status of surveillance techniques and guidance concerning the anticipated evolution and their capability to meet the demands of a changing operational environment. It proposes a roadmap detailing a path to achieving the surveillance infrastructure required to meet future needs in an efficient manner taking advantage of new Surveillance techniques and technologies such as ADS-B, WAM and MSPSR. It describes how the changes foreseen may impact upon the SESAR ATM Masterplan (Ref Doc 2) and to supporting literature such as the document Strategic Guidance in Support of the Execution of the European ATM Masterplan (Ref Doc 3). The surveillance roadmap indicates when the surveillance techniques will be available and how the different techniques will be used in support of existing operational services and future improvements developed by SESAR. It also provides an indication of the drivers for change behind the evolution. The scope of this Roadmap does not cover weather radar, wake vortex detection, airport surveillance or debris detection. Its primary focus is upon the ground based surveillance of the airspace and the supporting avionics used in TMA and En-Route applications and surveillance used to support air-air applications. The impact of ACAS upon the 1030/1090 MHz frequencies is addressed within the scope of this paper. The roadmap identifies the need for supporting legislation and a support infrastructure but does not address operational procedures or system components such as controller tools. 1.3 Intended readership The stakeholder groups considered throughout the scope of this project were: Aeronautics industry. Airport operators. Airspace users. Air Navigation Service Providers. EUROCONTROL Agency. International organisations. Regulatory bodies. Military Authorities in their different roles as regulator, ANSP, airspace user and airport operator. Non-ECAC Organisations. European Commission. SESAR Joint Undertaking. 7 of 70

8 1.4 Inputs from other projects In addition to the information derived from the numerous supporting activities conducted within the scope of SESAR WP further influences also arose from: SESAR WP a Surveillance Ground System enhancements for ADS-B SESAR WP Spectrum Management and impact assessment SESAR WP 9.47 re Hybrid Surveillance (ACAS and ADS-B) SESAR Masterplan Update Cycle and B4.3 project activities. 1.5 Acronyms and Terminology A comprehensive list of acronyms and definitions is provided in Appendix A. 8 of 70

9 2 Influences on the Evolution of European Surveillance This section synthesises the key findings of the previous activities conducted within the scope of the SESAR WP project and how these could influence the evolutionary path of the European surveillance infrastructure. The focus of the WP Project is upon TMA and En-Route applications however much of the content may be equally applicable to other surveillance applications. 2.1 Operational Environment and Drivers for Change General The objective of a surveillance infrastructure, be it civil, military or combined, is to provide the required functionality and performance to enable a safe, efficient and cost-effective service. New performance targets and associated operational requirements are emerging from Single European Sky legislative packages and SESAR initiatives. Whilst not explicit in introducing requirements upon surveillance they introduce implicit requirements and drive changes to the existing surveillance infrastructure. This evolution needs to be managed, for it will also be influenced by an extensive range of other factors such as global interoperability, civil-military coordination and changes to the composition of the aircraft fleet with the introduction of very light jets and unmanned aircraft. Through the increasing deployment of Wind-Turbines, the clutter environment is changing. Furthermore, cost and radio frequency spectrum efficiency considerations will be conducive to a rationalisation of the current infrastructure, in which legacy systems will be phased out as soon as practicable and new, more efficient technologies will be introduced. The number of stakeholders with responsibilities within the sphere of surveillance is increasing. Current stakeholders include civil and military air navigation service providers, aircraft operators (civil and military, commercial and general aviation), avionic manufacturers, regulatory authorities (civil and military national authorities and the European Aviation Safety Agency (EASA)), EUROCONTROL and the European Commission. Each of these brings unique contributions which reflect their specific expertise and perspective. The traditional means of surveillance (Independent Non-Cooperative PSR and Dependent Cooperative -SSR) remain dominant in supporting current European ATM operations. SSR Mode S is in increasing operational use throughout Core Europe. WAM is being increasingly deployed initially addressing niche requirements but its use and market penetration is now expanding. Whilst certain applications in the use of ADS-B 1090 MHz are currently under validation pending wider availability of appropriately configured avionics to enable full operational use it is noted that initial exploitation of ATSAW and ADS-B NRA within Europe has commenced. The ASTERIX data-format is the main format used for the transfer and sharing of surveillance information. Changes arising through the introduction of functional airspace blocks (FABs) are influencing the surveillance architecture required. These have the potential to reduce the requirements for surveillance sensors providing cross-border surveillance and afford a means to support the widespread sharing of surveillance data. Such aspects can be key contributors to realising efficiency gains. It is recognised that a degree of overlap of surveillance cover is required to support the transfer of radar control (see ICAO EUR Doc Ref Doc 8) and to ensure appropriate service continuity. An assessment of the benefits that data sharing (including releasable military data) can bring could potentially reduce this level of duplicated coverage. This would bring benefits in terms of reduced cost but also reduced transponder occupancy and reduced 1030/1090 MHz spectrum occupancy. 9 of 70

10 2.1.2 Operational Environment Performance Requirements An ANSP needs to demonstrate to their Regulatory Authority that the performance that is required by and achieved by their surveillance infrastructure is acceptable and appropriate however the recent emergence of new technologies such as WAM and ADS-B has necessitated a change to the way performance requirements for surveillance systems are documented. The EUROCONTROL Specification for ATM Surveillance System Performance which details the required performance of a surveillance infrastructure in a technological independent manner (Ref Doc 9) could be used as one of the means to support ANSPs in this regard. The performance of the surveillance system relies upon aircraft being appropriately equipped with correctly functioning and interoperable transponders and appropriate avionics RF Environment There is increasing pressure for ATM to improve the manner in which the RF spectrum currently assigned to it is managed and used. This is coming not only from parties external to ATM but the increasing use of the 1030/1090 MHz band is also increasing pressure from within. Congestion of the RF environment is already becoming a problem area in dense traffic and ground system areas and, unless appropriate mitigations including rationalisation are introduced, it will continue to get worse and could eventually compromise system performance. The RF spectrum is core to the correct functioning of all surveillance techniques and technologies. Demands upon the spectrum need to be managed and improvements need to be made to accommodate the increasing demands being placed upon it both from within ATM and from external sources Spectrum Overview Until 2030 ATC surveillance in Europe will rely on 3 families of surveillance technology 1. Independent Cooperative Surveillance (using 1030/1090 MHz) (Such as SSR, SSR Mode S and WAM) 2. Dependent Cooperative Surveillance (using 1090 MHz) 3. Independent Non Cooperative Surveillance (using spectrum allocated within L Band and S Band). In addition the 1030/1090 MHz SSR bands also support the safe operation of airborne safety nets (i.e. ACAS) and of forthcoming air to air applications (e.g. in-trail procedure) and are needed to support the deployment of cooperative surface surveillance systems at airports. ADS-B operations rely on GNSS and the RF bands in which it operates (dependent upon which GNSS technology is used on board the aircraft. Options could include GPS, GLONASS, Galileo or COMPASS-Beidou). Either Active or Passive Multi-static PSR technology could, subject to development and deployment, replace classical mono-static PSR technology. As Active MSPSR is expected to utilise an L-band frequency bandwidth narrower than those currently assigned to classical PSR it could be envisaged that some portions of both the L-Band and the S-Band could be released for non-atm application. Widespread deployment of MSPSR may require a co-ordinated frequency allocation mechanism to fully exploit the ability to reduce spectrum requirements. As reflected in SESAR WP SESAR Spectrum Strategy (Ref Doc 10) it is assumed that the spectrum currently allocated to these types of systems will continue to be used up to at least 2030 and must be protected against interferences from other systems to ensure the safe operation of surveillance ATC. 10 of 70

11 A mix of different links to support ADS-B operations is possible. However such an approach introduces a degree of system complexity by requiring multiple band receivers or by requiring additional ground function to rebroadcast the data received from one link onto the other link (ADS-B Rebroadcast) and in some instances uses elements of spectrum that are already heavily utilised. Whilst these links may be used elsewhere on the globe this roadmap for Europe does not foresee the use of links other than 1090 MHz for Surveillance applications /1090 MHz Frequency Band The high number of SSR Mode A/C radars configured with relatively high interrogation rates and interrogator power has, over recent years, lead to congested usage of the 1030/1090 MHz frequency band. As ACAS and all the cooperative surveillance techniques are dependent upon this frequency band its use is considered to be fundamental to the future of surveillance. Deploying an alternative band would be expensive, time consuming and would introduce technical difficulties. It is preferable to manage, monitor and protect the current frequency assignments in recognition that the 1030/1090MHz as a valuable asset that is to be used with care. The protection of the 1030/1090 MHz frequencies is a key objective of this surveillance roadmap. Various measures ranging from the removal of spectrally inefficient Mode A/C SSRs (such as promoted through the Implementing Regulation No 1206/2011 Ref Doc 6) through to improvements in ACAS technologies (hybrid surveillance) or the clustering of SSR Mode S ground-stations will lead to improvements in this band and obviate the need for deployment of an alternative frequency band. The deployment of WAM techniques has the potential to reduce excessive transmissions in the 1030/1090 MHz band when compared with conventional SSR systems. However it should be noted that Active Wide Area Multilateration systems configured with broad-beam or omni-directional transmit stations can also place a significant impact upon this frequency band and the surveillance sensors that depend upon it Primary Surveillance Frequency Bands There is growing pressure being exerted by non-atm users, particularly mobile phone and television bodies, for access to the two frequency bands (L Band and S Band) used by civil and military PSR radars and that are allocated internationally for radio-navigation purposes. It is reported that some governments are considering the introduction of spectrum charging. As traditional Primary Surveillance Radars require a broad RF spectrum their continued use may become expensive for some ANSPs. See WP D26 (Ref Doc11) for further details. Such demands upon spectrum usage are placing pressure upon the use of conventional Primary Surveillance Radars. Recent technological developments point to a new type of Independent Non- Cooperative surveillance technique, Multi-Static PSR, which could, subject to verification of viability, address these issues ATC Controller Efficiencies Surveillance systems support Air Traffic Controllers in conducting their tasks in an efficient manner. Modern systems, such as Mode S EHS, ADS-B and WAM, not only present a clearer, less garbled image but also provide additional benefits over conventional systems by providing timely indication that an aircraft is not complying with, or deviating from ATCs instructions. The fact that the information is constantly being updated without the need for ATC intervention or voice communications between ATC and the aircrew can also help alleviate RF congestion in the frequencies used for voice communications. The attribution of such benefits to surveillance is difficult to quantify. Modern and emerging surveillance systems provide improved mitigation against human error and also provide benefits in terms of human factors such as: Safety Workload and capacity Efficiency 11 of 70

12 Modern Surveillance Systems (and the tools they support) provide benefits in terms of safety through: Clear presentation of call-sign and level Automatic same level indication Improved situational awareness o o Use of certain down-linked aircraft parameters (DAPs) and 25 altitude reporting to improve radar tracking algorithms. Conflict detection tools using values derived from Mode-S DAP or ADS-B ADDs are potentially more consistent than those using data derived from radar plots. Potential reduction in level busts o o o Display of Vertical Stack Lists Down-linking of pilot Selected Flight Level supports the resolution of issues stemming from: Correct pilot read-back followed by incorrect action Incorrect pilot read-back by correct aircraft Pilot read-back by incorrect aircraft Same Selected Flight Level Alert Similarly benefits can be accrued in terms of workload, capacity and efficiency: Reduction in Radio Transmission (between controller and pilot). Display of DAPs. Overall enhanced situational awareness. Reduced clutter. Garbling, compared to conventional SSR Mode A/C, is reduced through clustered Mode S, ADS-B and WAM. Improve management of aircraft in stacks. ANSPs may wish to consider how best to exploit these potential benefits when conducting an upgrade or a rationalisation exercise (see Ref Doc 1) that introduces new surveillance techniques which make additional aircraft derived data available and whether their introduction merits consideration within the scoring mechanism applied within the rationalisation methodology Composition of the Aircraft Fleet Changes to the Aircraft Type and Numbers Despite recent declines in the numbers of flights made per year the long term trend is predicted to remain in an upward direction albeit less that the capacity requirements predicted within the original high level SES objectives. The EUROCONTROL Long-Term Forecast of IFR Flight Movements 2010 to 2030 report (Ref Doc 12) focuses on the developments between 2016 and The forecast is for 16.9 million civil IFR flight movements in the EUROCONTROL Statistical Reference Area (ESRA) in 2030, 1.8 times the traffic in This is an average growth of 1.6%-3.9% per year (with 2.8% considered most likely). The growth will be distributed unevenly in time and across regions. It will be faster in early years, stronger in Eastern Europe and for arrivals/departures to/from outside Europe than for intra-europe flights. It should be noted that neither military IFR and OAT traffic nor General Aviation is included in these predictions yet may impact upon the requirements of the surveillance systems. 12 of 70

13 Figure 1: Long Term Trend in European IFR Air Traffic (Source: Eurocontrol) Growth, in percentage terms is expected to be stronger in Eastern Europe where the market is relatively less mature and the States are catching up with the more developed Western economies. The total number of flights is represented in Figure 2. Future air traffic will be limited by capacity at the airports, million flights will not be accommodated in 2030, 5%-19% of the demand. Congested airports create pressure on the flow of operations in the network and will exacerbate delays. Resolving such issues may introduce requirements for additional surveillance sensors. Even with airport capacity restrictions airports will grow. In 2030, it is predicted that there will be airports as big as the top 7 are now. Some of the faster growing East-European airports will join the top 25. European hubs will be faced with competition from hubs outside Europe, primarily in the Middle-East. Figure 2: Predicted traffic in of 70

14 Aircraft fleet types The composition of the catalogue of aircraft types operating in European airspace is evolving. The introduction of super heavy jets, such as the A380 will bring challenges to areas such as airport design and operation as well as wake vortex issues however, from a surveillance perspective the fact that the aircraft is fully equipped to operate in controlled airspace means that it does not need further significant consideration. (It is to be noted that sufficient provision is included in ADS-B specifications to accommodate a broadcast of distance between the transponder location and nose tip necessary for surface movement operations). The potential consequences of changes to fleet type through the introduction of Very Light Jets (VLJs), Remotely Piloted Aircraft (RPAs) and low Radar Cross Section (RCS) composite body aircraft should also be considered from a surveillance perspective Very Light Jets (VLJs) Very Light Jet (VLJ) is the term used to describe a range of small jet aircraft, seating 4-8 people, with a maximum take-off weight below 3000 kg. They do not have a separate ICAO classification and are considered as Light Aircraft. They have very dissimilar performance characteristics to commercial jet aircraft with lower landing and cruising speeds differences that may place new requirements upon the surveillance infrastructure. Whether or not VLJs are to be ACAS equipped remains under discussion. As such aircraft operate in the same airspace as commercial aircraft there are arguments for amending the current ACAS thresholds to accommodate such aircraft. However should a large number of VLJs become operational or the revised ACAS thresholds include a large number of aircraft that are currently excluded from these requirements there will need to be a consideration of the impact upon the 1030/1090 MHz frequency. Development and deployment of VLJs is under way with forecasts of a significant enough growth in Europe for there to be concern as to their likely impact, and how they will be integrated with today s larger commercial traffic Remotely Piloted Aircraft (RPA) RPA Operations The number of RPA in operation across the globe is steadily increasing. Within Europe, besides military applications, a number of RPA are already being used for civilian applications such as high voltage power cable health-assessments, and crop and fishery tasks as well as border control and to support policing. It is anticipated that the number of platforms in operation will increase further with their regular operation in European airspace foreseen from ICAO and EUROCAE specifications for such aircraft are currently being developed. The basic principle being adopted for the operation of RPA operated in controlled airspace (outside of visual line of sight of the ground-based pilot ) is that the aircraft must adhere with the same avionic equipage required for conventional aircraft e.g. they need to carry transponders if the airspace requires them for conventional aircraft. (The deployment of ACAS on such aircraft is not yet decided). The application of this principle simplifies matters from a surveillance perspective however a significant amount of effort may still be required by ANSP s and their regulatory counterpart to consider how operations of such platforms are to be integrated into daily practice and how aspects like the allocation and management of the 24 bit ICAO aircraft code are to be managed and the manner in which ATC are made aware of indicators such as loss of control link. As such aircraft may only exhibit a low radar cross section the ANSP may also need to consider whether the existing PSR are capable of providing a safety mitigation in the event it is required if the aircrafts transponder fails (see section ). SESAR Work-packages 9 and 15 address to a limited extent the integration of RPA into the European ATM infrastructure. There are elements of RPA operations that are particularly well suited to SESAR given that its wide scope embracing all of ATM includes SWIM (System Wide Information 14 of 70

15 Management), improved sense and avoid, advanced communications, precise trajectory management, ASAS (Airborne Separation Assistance Systems) and autonomous flight. The following section focuses upon the potential changes that may be required to surveillance functionality to support operations by such aircraft Possible Impact of Remotely Piloted Aircraft upon Surveillance The widespread deployment of Remotely Piloted Aircraft (RPA) into operations in controlled airspace is expected to happen towards the latter end of the time-period of the ATM Masterplan. There are three matters, namely 'sense and avoid', equipage requirements and flight profiles that may have implications upon surveillance components in terms of performance requirements, design and integration into operations. A "Sense and Avoid' function will be required in the RPA not only to avoid all obstructions in the flight path; buildings, terrain, pylons, wires but also other aircraft. However RPA platforms cover a broad spectrum of size, weight and performance envelopes. Smaller RPA may not be capable of carrying or powering the conventional ACAS systems. Some larger RPA platforms may not be able to follow ACAS Resolution Advisories. Consequently new systems, procedures and practices will need to be developed. RPAs may have a reduced radar cross section - this could mean that coverage provided by current PSRs, including military, may be reduced for such aircraft. A reduction in detection capability would impact upon the system safety case. The flight profile or performance envelope of some RPA may also impact upon the performance requirements of the surveillance infrastructure. Some RPA will fly above the altitude of normal manned aircraft and will impact upon current separation minima only during ascent and descent phases of flight. Other large RPA will operate 'nonconventional' missions flying at slow speed, not necessarily conducting 'point to point' operations. Similarly some RPA may fly at lower altitudes in airspace not currently covered by existing surveillance systems. The performance envelop of an RPA (Tighter turns, higher altitude, slower / almost static operations at height) may place new demands upon mono and multi-sensor trackers and controller support tools. ATC may introduce a specific user requirement regarding confirmation of whether an aircraft is manned or unmanned. Such information could be broadcast from RPA equipped with ADS-B or Mode S EHS capabilities. The receipt, processing and data transfer for presentation of such data will place new requirements upon the surveillance infrastructure. Consideration could also include whether an indication to a controller is necessary that a RPA has lost contact with its pilot and is therefore not under control but is following a pre-defined return route. These aspects will need to be addressed to ensure that RPA can be operated safely in controlled and non-controlled airspace. (See SESAR Work-packages 9 and 15) Reduced Radar Cross Section Recent developments in composite technologies have provided aircraft manufacturers with a material that is both light and strong and thus ideal for aircraft construction. Such material however can also exhibit a low radar cross section (RCS). Informal feedback from ANSP s has confirmed that poor PSR returns are being observed from some small pleasure type aircraft built from composite materials. The presence of low RCS or micro-light aircraft operating in the vicinity of, and in recorded cases infringing upon controlled airspace are influencing ANSP s decisions regarding the retention and required performance of independent non-cooperative surveillance systems. When conducting assessments of system performance requirements and capabilities ANSP s should consider whether current PSR will continue to provide adequate safety mitigation in the event they are to be used when the cooperative surveillance system or avionics fails or to detect airspace infringement of non-avionic equipped aircraft. The detection of small aircraft with an RCS that is lower than for today s fleet of aircraft could place increasing demands upon non-cooperative surveillance systems. Whilst the requirement to provide safety mitigation for aircraft with a low RCS could, potentially, be achieved through the use of military Air Defence radar data it may be more likely to form a user requirement for the development or procurement of new PSRs (with improved detection capabilities) 15 of 70

16 or in the development of MSPSR as this technique is likely, subject to successful development and validation, to fulfil this requirement Legislation Summary The European Commission now adopt an active role in supplementing the legislative capabilities of individual states National Supervisory Authorities or Civil Aviation Authorities. The publication of AICs, AIPs or other local legal instruments can now be supplemented by regulations published by the European Commission. A number of important developments have recently taken place with regard to ATM. These include the publication of a number of European Commission Regulations. These supplement existing legislation and include: Commission Implementing Regulation (EU) No 677/2011 laying down detailed rules for the implementation of Air Traffic Management (ATM) network functions and amending Regulation (EU) No 691/2010. (Published 7 th July 2011) (Informally known as the NM IR) (Ref Doc 4) Commission Implementing Regulation (EU) No 1207/2011 laying down requirements for the performance and the interoperability of surveillance for the single European sky. (Published 22 nd November 2011) (Informally known as the SPI IR) (Ref Doc 5) Commission Implementing Regulation (EU) No 1206/2011 laying down requirements on aircraft identification for surveillance for the single European sky. (Published 22 nd November 2011) (Informally known as the ACID IR) (Ref Doc 6) Commission Regulation (EU) No 1332/2011 laying down common airspace usage requirements and operating procedures for airborne collision avoidance. (Published 16 th December 2011) (Informally known as the ACAS IR) (Ref Doc 7) The publication of Implementation Regulation No 1207/2011 (Ref Doc 5) by the European Commission establishes a European wide instrument to introduce ADS-B carriage requirements upon aircraft whose take off mass or maximum cruising true airspeed exceed defined thresholds. These requirements are one of the greatest influences behind how the surveillance infrastructure will change in the next decades. To gain the maximum benefit from an ADS-B surveillance infrastructure it is necessary that 100% of the aircraft under ATC control are appropriately ADS-B equipped. Achieving this will require additional mandates. In the first instance it is anticipated that these will be published locally to introduce ADS-B requirements upon all aircraft within defined volumes of airspace and to preclude ADS-B transmissions by non-approved ADS-B configurations. Introducing such requirements in designated airspace could also be achieved through additional European wide legislation such as a subsequent Implementing Rule. Furthermore the Implementing Regulation No 1207/2011 not only supplement the existing mandates published for core Europe for such aspects as Mode S ELS and EHS but it also replicates such requirements across all of Europe. 16 of 70

17 Key Dates in Legislation Affecting the Surveillance Infrastructure The legislation identified above introduces a number of milestone dates which pave the way to the surveillance infrastructure of In summary form those that become effective after the publication date of this paper are detailed in Table 1: Key Dates Contained in Published European Commission Implementing Regulations below: Date Milestone Source of Requirement 8 Jan Aircraft with an individual certificate of airworthiness first issued on or after 8 January 2015 that are operating IFR/GAT flights in European airspace are to be equipped with secondary surveillance radar transponders that have appropriate Mode S ELS capabilities. Implementing Regulation for performance and interoperability of surveillance for the single European sky. 8 Jan Aircraft with a maximum certified take-off mass exceeding kg or having a maximum cruising true airspeed capability greater than 250 knots and with an individual certificate of airworthiness first issued on or after 8 January 2015 that are operating IFR/GAT flights in European airspace are to be equipped with secondary surveillance radar transponders and avionics that have appropriate Mode S EHS and ADS-B capabilities. (Aircraft of specific types with a first certificate of airworthiness issued before 8 January 2015 that have a maximum take off mass exceeding kg or a maximum cruising true airspeed greater than 250 knots that do not have available on a digital bus on-board the aircraft the complete set of parameters required for Mode S EHS compliance may be exempted from complying with the EHS requirements). Implementing Regulation for performance and interoperability of surveillance for the single European sky. 5 Feb By 5 February 2015 Member States shall ensure that a secondary surveillance radar transponder on board any aircraft flying over a Member State is not subject to excessive interrogations that are transmitted by groundbased surveillance interrogators and which either elicit replies or whilst not eliciting a reply are of sufficient power to exceed the minimum threshold level of the receiver of the secondary surveillance radar transponder. Member States shall also ensure that the use of a ground based transmitter operated in a Member State does not produce harmful interference on other surveillance systems. 5 Feb Member States shall ensure that, by 5 February 2015 at the latest, a safety assessment is conducted by the parties concerned for all existing surveillance systems. Implementing Regulation for performance and interoperability of surveillance for the single European sky. Implementing Regulation for performance and interoperability of surveillance for the single European sky. 17 of 70

18 Date Milestone Source of Requirement 1 Dec All aircraft required to equip and operate ACAS shall be configured with ACAS II v7.1 1 July 2017 Aircraft of specific types with a first certificate of airworthiness issued before 1 January 1990 that have a maximum take off mass exceeding kg or a maximum cruising true airspeed greater than 250 knots may be exempted from complying with the requirements of SSR antenna diversity. The Member States concerned shall communicate to the Commission by 1 July 2017 at the latest, detailed information justifying the need for granting exemptions to these specific aircraft types based on the criteria of paragraph 5. 7 Dec Civilian Aircraft Operators shall ensure that: (a) aircraft with an individual certificate of airworthiness first issued before 8 January 2015, are equipped with secondary surveillance radar transponders with appropriate ELS capabilities (b) aircraft with a maximum certified take-off mass exceeding kg or having a maximum cruising true airspeed capability greater than 250 knots, with an individual certificate of airworthiness first issued before 8 January 2015 are equipped with appropriate Mode S ELS and ADS-B avionic configurations. (c) fixed wing aircraft with a maximum certified take-off mass exceeding kg or having a maximum cruising true airspeed capability greater than 250 knots with an individual certificate of airworthiness first issued before 8 January 2015 are equipped with appropriate Mode S ELS and EHS avionic configurations. Implementing Regulation on common airspace usage requirements and operating procedures for airborne collision avoidance. Implementing Regulation for performance and interoperability of surveillance for the single European sky. Implementing Regulation for performance and interoperability of surveillance for the single European sky. 7 Dec Jan July July 2018 Member States shall ensure that, by 7 December 2017 State aircraft operating IFR/GAT flights in European airspace are equipped with secondary surveillance radar transponders with appropriate ELS capabilities Member States shall ensure that, by 1 January 2019 transport-type State aircraft with a maximum certified takeoff mass exceeding kg or having a maximum cruising true airspeed capability greater than 250 knots, operating IFR/GAT flights in European airspace are equipped with appropriate ADS-B, Mode S ELS and EHS avionic configurations. Member States shall communicate to the Commission by 1 July 2016 at the latest the list of State aircraft that cannot be equipped with secondary surveillance radar transponders that comply with the Mode S ELS requirements, together with the justification for nonequipage. Implementing Regulation for performance and interoperability of surveillance for the single European sky. 18 of 70

19 Date Milestone Source of Requirement Member States shall communicate to the Commission by 1 July 2018 the list of transport-type State aircraft with a maximum certified take-off mass exceeding kg or having a maximum cruising true airspeed capability greater than 250 knots, that cannot be equipped with appropriate ADS-B and Mode S EHS avionic configurations together with the justification for nonequipage. 31 Dec Dec Jan Member States shall communicate to the European Commission by 31 December 2017 at the latest, those approach areas where air traffic services are provided by military units or under military supervision and when procurement constraints prevent compliance to the ACID Implementation Regulation. The date of compliance for these areas shall not be later than 2 January The Commission, in consultation with the Network Manager (Eurocontrol) may review the exemptions communicated that could have a significant impact on the EATMN. The decision of the European Commission shall be communicated before 31 December Implementing Regulation on aircraft identification for surveillance for the single European sky and Implementing Regulation for performance and interoperability of surveillance for the single European sky. 2 Jan ANSPs shall ensure that, by 2 nd January 2020 the cooperative surveillance chain has the necessary capability to allow them to establish individual aircraft identification using the downlinked aircraft identification feature Implementing Regulation on aircraft identification for surveillance for the single European sky Table 1: Key Dates Contained in Published European Commission Implementing Regulations 2.2 Avionics Supporting Surveillance As an aircraft flies within the airspace of a number of States the avionics it carries on board becomes the common-denominator across the European Surveillance infrastructure and is needed to ensure seamless operation of the aircraft throughout European airspace. Increasing the capabilities of transponders and their supporting avionics enables ANSPs on the ground to exploit new, cheaper and more capable technologies, to process increasing air traffic densities and to conduct more demanding separation applications whilst improving safety. The migration of surveillance functionalities from the ground to the aircraft represents a fundamental aspect in which the scope and the manner of how surveillance is undertaken and how it will evolve in the coming years. Timely coordination with civilian and State aircraft operators is necessary to prevent significant delays for full implementation of such functionalities Equipage Requirements Current requirements In a number of States in Core Europe mandates have been established that have led to the replacement of the conventional SSR Mode A/C systems carried on board aircraft by SSR Mode S avionics. In certain transponder mandatory zones these requirements can also extend to Mode A/C or Mode S ELS equipage for flights conducted as VFR. In a number of States in Core Europe mandates have been established that require SSR Mode S Enhanced Surveillance systems to be carried on board aircraft whose weight or speed exceed specified thresholds (and which are capable of being upgraded to Mode S EHS). 19 of 70

20 As the majority of European flights are conducted within the Core Area a significant percentage of aircraft operating in Europe are thus already equipped with Mode S ELS and, for aircraft exceeding specified weight and speed criteria (and which are capable of being upgraded) with Mode S EHS. The upgrade of avionics to the more demanding Mode S requirements was and still is not without technical issues (especially for State aircraft). Indeed a number of design anomalies have been identified and despite rectification means being available the issue remains unresolved on a significant number of aircraft. As a consequence, some Mode S ground-stations continue to be operated in a sub-optimal manner (with respect to RF) in order to ensure that anomalous aircraft are correctly detected. The publication of European Commission Implementing Regulation1207/2011 (Ref Doc 5) supplements existing (locally issued) Mode S carriage requirements and introduces European wide requirements for aircraft with a maximum Take Off Mass greater than 5700kg or a Maximum Cruising True Air Speed greater than 250 knots to be appropriately configured with ADS-B 1090MHz Extended Squitter (ES) and Mode S (ELS and EHS) avionics. However this implementing regulation only applies the EHS and ADS-B Out requirements to a sub-set of aircraft (those exceeding defined weight and speed thresholds, including State aircraft). However, the use of ADS-B is optimised when 100% of the aircraft in a defined volume of airspace are equipped. Additional legislation is therefore required to support the operational introduction of standard ADS-B applications. This would be achieved either through the segregation of airspace or ADS-B equipage on all aircraft. The inclusion of such requirements through a European wide Implementing Rule could be considered in the longer term Near Future Requirements The avionics specified in the above regulation brings improvements to the quality of surveillance and paves the way for airborne self assured separation. The availability of Aircraft Derived Data (ADD) on the ground, such as available through Mode S EHS, WAM and ADS-B, has also being demonstrated to bring significant safety benefits. It is recognised that changes to an aircraft avionics places a cost burden on the aircraft operator however the introduction of Mode S and ADS-B ES functionalities is considered a necessary measure to support future ATM. SESAR WP 9.24 studies the possibilities to implement ADS-B IN/OUT functions on board all types of State aircraft by reutilisation of existing on board equipage to the maximum intend possible. The development of suitable ADS-B avionics for use with smaller or all aircraft is to be expedited Extension to Avionic Capabilities The following should be considered within the ATM Masterplan updates as they will impact upon the time-scales for the availability of additional aircraft derived data and may be constrained by developments and deployment of transponder modulation techniques (and, where necessary, adaptations to ground-stations) that may be necessary to support the increased capacity demands. Deployment should be dependent upon a proven cost-benefit case Aircraft Derived Data Whilst Implementing Regulation1207/2011 (Ref Doc 5) took into account and, when published, specifications such as CS-ACNS (Ref Doc 14) will take into account the ADD requirements of SESAR Operational Improvements (OIs) that were sufficiently mature for their inclusion it may be that the further development of some SESAR OIs necessitates the provision of further ADDs. The down-linking of additional data such as meteorological data, runway friction, wake vortex information or even details of the VHF voice frequency that is being used could also be considered. However whilst it is feasible to extend the number of parameters that can be broadcast it is necessary that any further additions to the list of parameters should be carefully managed to minimise the cost burden on aircraft operators and the ability of the RF environment to support additional transmissions. 20 of 70