SRC POSITION PAPER. Edition December 2011 Released Issue

Transcription

1 E U R O C O N T R O L SRC POSITION PAPER Review of the Preliminary Safety Case for Airborne Traffic Situational Awareness for Enhanced Visual Separation on Approach, PSC ATSA-VSA Version 2.0, dated May 2011 Edition December 2011 Released Issue

2 Position Paper and Advice to States Review of the Preliminary Safety Case for Airborne Traffic Situational Awareness for Enhanced Visual Separation on Approach, PSC ATSA-VSA Version 2.1, dated August This paper denotes the SRC s position and advice to ATS implementers and National Supervisory Authorities (NSAs) ensuing from a review of the Preliminary Safety Case for Airborne Traffic Situational Awareness for Enhanced Visual Separation on Approach, PSC ATSA-VSA Version 2.1, dated August The review was conducted by nominees from NSA/Member States of the SRC Coordination Group following a mandate approved at the 33 rd meeting of the Safety Regulation Commission held on 01/02 October The only State represented in the ATSA-VSA review task force was Slovakia. Additional substantive comments were received from IFATCA and Sweden. The comments and positions contained in this Position Paper are for information purposes only. They do not constitute formal approval, acceptance or certification or other legal commitment, which remain the responsibility of the authorities and entities concerned, and shall not be interpreted, or inferred as being such. This Position Paper is provided without any warranty of any kind, either express or implied. EUROCONTROL shall not be held liable for any direct or indirect loss resulting from the use of the review. SRC Position The Preliminary Safety Case for Airborne Traffic Situational Awareness for Enhanced Visual Separation on Approach (ATSA-VSA) - hereafter called the PSC - presents a credible set of generic arguments for the safe provision of the ATSA-VSA system in augmenting own visual separation on approach. Implementers choosing to deploy ATSA-VSA will need to develop elements that will be required by the local NSA for a local implementation eg local Safety Case and cannot rely on the PSC alone. Guidance Material is developed throughout the PSC to identify the issues that need to be addressed at the local level. The PSC contains a generic set of Arguments in the form of Goal Structuring Notation that can be re-used by implementers when developing elements that will be required by the local NSA for a local implementation eg local Safety Case. Where attention to the key issues identified and attached to this Position Paper has been made, the SRC consider the PSC for ATSA-VSA a valuable information document for implementers to use as a starting point for developing elements that will be required by the local NSA for a local implementation eg local Safety Case of ATSA-VSA. ADS-B-Applications Context and Development The EUROCONTROL CASCADE Programme co-ordinates the implementation of initial ADS-B applications in Europe. [WAM implementation was incorporated into the CASCADE Programme activities in January 2010]. Global aspects of requirements definition, certification basis and development of standards are coordinated within the Requirements Focus Group, (RFG). The RFG is a joint activity between RTCA, EUROCAE, FAA and EUROCONTROL, combining technical and operational expertise with additional participation from Airservices Australia, JCAB (Japan) and many industrial partners.

3 In particular, RFG coordinated EUROCAE ED-160 / RTCA DO-314 joint standard that provides the minimum, Safety and Performance requirements (SPR) and Interoperability requirements (INTEROP) for the implementation of the ATSA-VSA system. ATSA-VSA is one of the applications defined by the RFG as part of an initial package of ground and airborne surveillance applications enabled by ADS-B (initially derived from CARE-ASAS "Package 1 applications). The airborne and ground based ADS-B surveillance applications supported by CASCADE as part of the RFG Scope of work are: ADS-B Ground-Based Surveillance Applications: ADS-B-NRA: Enhanced ATS in non-radar areas using ADS-B surveillance ADS-B-RAD: Enhanced ATS in radar areas using ADS-B surveillance ADS-B-APT: ADS-B Airport surface surveillance. ADS-B Airborne-Based Surveillance Applications: ATSA-VSA Enhanced visual separation on approach ATSA-ITP In-trail procedure in oceanic airspace ATSA-AIRB Enhanced traffic situational awareness during flight operations ATSA-SURF Enhanced traffic situational awareness on the airport surface. ATSA-VSA Overview Part of the EUROCONTROL CASCADE Programme, the ATSA-VSA (Airborne Traffic Situational Awareness for Enhanced Visual Separation on Approach) system is defined as all the elements (people, procedures and equipment) required to enhance existing ICAO (or State defined) own visual separation on approach operations through the use in the cockpit of a Traffic Display that graphically depicts ADS-B derived traffic information to support Airborne Traffic Situational Awareness. (Ground surveillance remains unchanged). The ATSA-VSA application assists flight crew, during a visual approach, with the visual acquisition and identification of reference aircraft to facilitate the operation of "maintaining own separation". Furthermore, it supports flight crew in maintaining visual contact with reference aircraft and provides more precise distance from the reference aircraft than eyesight can estimate. The Traffic Display will augment the verbal traffic information provided by the controller and out of the window information to support the flight crew in their: visual acquisition of the preceding aircraft; task to maintain visual separation from the preceding aircraft. As a means of implementation of ATSA-VSA system, several standards have been specifically developed. The EUROCAE ED-160 / RTCA DO-314 joint standard includes two types of procedures for ATSA-VSA, (Basic and Advanced). The SRC wishes to highlight that the ATSA-VSA PSC is scoped to the Basic Procedure only. At the time of writing, there are no notified intentions to adopt the Advanced Procedure in Europe. Introduction to the ATSA-VSA Operation Present Situation To increase runway capacity, some airports permit operations based on flight crew being responsible for maintaining own separation from a preceding aircraft by visual means own visual separation on approach ; (ICAO Procedures for Air Navigation Service PANS- ATM Doc 4444 (sections 6.1.c, and b), or in accordance with specific operations approved by individual States.

4 In the vicinity of aerodrome, the controller delegates the responsibility to the flight crew of an aircraft, referred to as the Succeeding Aircraft, to maintain own visual separation on approach with respect to an aircraft ahead, referred to as the Preceding Aircraft. The flight crew of the Succeeding Aircraft must report that the other aircraft is in sight and that own visual separation on approach can be maintained before the controller issues the clearance for own visual separation on approach. This procedure permits reduced separation between the two aircraft. The preceding aircraft may be either ahead and approaching the same runway (i.e. in-trail), or ahead and approaching an adjacent closely spaced parallel runway (i.e. when independent parallel approaches cannot be conducted because the runway separation is less than that required for independent approaches). The procedure is conducted in VMC and, if authorised, may be used during instrument approaches or visual approaches and for single or parallel runway operations. The own visual separation on approach operation is generally comprised of the following successive phases: 1) Visual acquisition: the objective is that the flight crew of the succeeding aircraft has visually acquired the preceding aircraft and that the visual contact can be maintained; and has reported visual contact on the preceding aircraft to the controller; 2) Clearance for maintaining own visual separation on approach ; 3) Maintaining own visual separation on approach. During this phase, the flight crew looks at the preceding aircraft out-the-window; decides if a manoeuvre is required based on visual information; and manoeuvres the aircraft if required to maintain own visual separation on approach. ATC separation is not provided to the succeeding aircraft with respect to the preceding aircraft; and 4) Termination phase: the clearance ends when the preceding aircraft lands. The ATSA-VSA System The ATSA-VSA system has been designed to enhance current own visual separation on approach operations through the provision of relevant data of the preceding aircraft to the flight crew of the succeeding aircraft by means of a Traffic Display. In particular, the ATSA-VSA Basic Procedure is based on existing ATC and flight crew procedures for own visual separation on approach. There is no change on the ground side introduced by this system and for the airborne domain, only changes in procedures for the use of the Traffic Display by the flight crew. SRC Advice on Coordination with Other Regulatory Areas The SRC recognises the opportunity to notify the broader aviation community of the work undertaken in the PSC to identify minimum requirements for the end-to-end implementation of the ATSA-VSA system. The SRC advises States that these requirements, in conjunction with EUROCAE ED-160 may be used as a component for certification / approval processes (e.g. MOPS, TSOs, etc.) used for aircraft type design approval, aircraft operator operational approval, and Air Traffic Services (ATS) provider operational approval.

5 Multiple Use of ADS-B Systems The SRC advises States that the airborne systems developed as part of the ATSA-VSA system may also be used in other surveillance applications based on ADS-B, e.g. AIRB, ITP, etc. This PSC and other PSC for individual ADS-B applications treat each application individually; interactions between two, or more ADS-B applications are out of scope of this PSC. The SRC advises States that when they wish to implement several ADS-B applications together, this could be accomplished by use of a local Safety Case taking account of the local combinations of ADS-B applications. Flight Crew Training The SRC reminds States that information provided by the Traffic Display is not a substitute to visual information and flight crews must maintain visual contact with the preceding aircraft throughout the own visual separation on approach operation. Therefore the Traffic Display must not be used alone. The SRC advises States that Flight crew training and familiarisation with the procedure and traffic display device shall be conducted. Monitoring of Use of Traffic Display The SRC advises States to put in place MANDATORY mechanisms to monitor the use of the traffic display by pilots to ensure that visual monitoring does not deteriorate. Human Factors and HMI Interface SRC advises States that human factors as well as HMI interface of Traffic Display design aspects are out of scope of the PSC, and have to be dealt with as part of the elements that will be required by the local NSA for a local implementation. Equipage Issues The SRC advises States that partial airborne ADS-B equipage (mix of ADS-B-OUT equipped and non equipped aircraft) associated with own visual separation on approach operations has implications for aircraft using the ATSA-VSA system, as this will result in incomplete traffic information being displayed. The SRC advises States that the PSC assumes all ADS-B-OUT aircraft are certified (see A002 in PSC). However, as there are options on how to accommodate possible variations of equipment that do not meet this assumption, reference should be made to GM004 in the PSC. SRC Advice Arising from the ATSA-VSA PSC Differences between PSC and Current local Operations and Environment The SRC advises States that the PSC includes the definition of the Operations, and the Operational Environmental conditions and the minimum end-to-end requirements for using the ATSA-VSA system. The SRC advises States that, if current operations are different from own visual separation on approach as described in the PANS-ATM Doc 4444 as above, the differences shall be documented and the impact of these differences shall be assessed.

6 The SRC advises States to verify if there are any differences between the Typical Operational Environment used in the PSC and the local Operational Environment, to document the differences and assess their impact in a Local Safety Case. The SRC advises States that this PSC does not address the implementation of ATSA-VSA system where own visual separation on approach operations do not currently exist. The SRC advises states that all current requirements for maintaining own visual separation on approach are still valid (whether ICAO or State defined) when supporting the ATSA-VSA system. ATC Training The SRC advises States that, although the ATSA-VSA Basic Procedure does not require modification to controllers procedures or additional information elements on the ground, training for controllers SHALL BE MADE MANDATORY to address the issues identified in GM 020 in the PSC. SRC Advise Arising from the PSC Structure Use of Assumptions The SRC advises States that assumptions are made in the PSC to support the safety argument. It will be necessary for each implementer to validate the applicability of these assumptions in their own operational environment, and if not valid, address them as part of the elements that will be required by the local NSA for a local implementation eg local Safety Case Safety Targets The SRC advises States that the PSC covers both the airborne and the ground elements. The safety targets have been set to ensure the end to end safety, as such these safety targets are distinct from the airworthiness approach as they have been set from an overall ATM perspective. These safety targets may not be consistent with those used in states. SRC advises States to consider the implications of their own Safety Targets on the resulting requirements as part of the elements that will be required by the local NSA for a local implementation eg local Safety Case. Risk Apportionment The SRC advises States that the risk apportionment approach used in the PSC is based on the use of ED-160/DO-314 which is based on ESARR 4/ED125. The SRC advises States to address the applicability of this approach, when combined with any existing local risk apportionment approach. Hazards The SRC advises States that the generic safety assessments for ATSA-VSA are based on hazards derived from current operations and environments. The SRC advises States to consider that new technologies may create as yet unidentified hazards. The SRC advises States to use monitoring data to identify other pre-existing or new hazards.

7 Security Issues The SRC advises States that, in common with other communication, navigation and surveillance technologies, ADS-B is sensitive to outside interference. The interference sources can be malicious or accidental and can occur intermittently or for an extended period. The SRC advises States that the PSC does not address the possible solutions to these aspects. Safety Issues Arising Through Implementation The SRC advises States that the PSC does not address the implementation, transition and in-service stages of the safety lifecycle. However, the SRC advises States that the change in separation assurance responsibilities from ATC to pilots in the 'own separation on approach' and ATSA-VSA may result in reduced distance between aircraft being applied. States should ensure that MANDATORY monitoring is applied to ensure that spacing applied by pilots while performing ATSA-VSA does not fall below the spacing applied during 'own separation on approach' Unintended Use The SRC advises States that the PSC does not address the abuse of, or intentional misuse of, information provided to the flight crew or the controller. Reference Material In order to provide appropriate and sufficient evidence to demonstrate the claim through the proposed arguments, the PSC presents information based on ED-160/DO-314, as well as from other standards and related activities (ICAO annexes and documents, EASA reference documents, other CASCADE Programme work and standards, etc.). The information presented in the PSC has been in some cases adapted and summarised from its original form in order to obtain a coherent and simplified document. The SRC advises States that the PSC does not supersede all assumptions and results made in these reference documents, in particular those from ED-160/DO-314. Applicable and Planned Regulations and Standards for Airborne Traffic Situational Awareness for Enhanced Visual Separation on Approach, PSC ATSA-VSA The SRC advises States that EC Regulations requires ANSPs to notify the NSA/State of changes to the ATM system in accordance with the classification set by the NSA/State of what constitutes a major or minor change. The SRC advises States of the EASA view that, in general, any change that introduces an application based on ADS-B shall be considered as a MAJOR change. Standards and manuals that could be applicable by NSA/States and ANSPs when considering ATSA- VSA implementation are: EUROCONTROL - Safety Case Development Manual, DAP/SSH/091, Edition 2.2. Nov EUROCONTROL - ANS Safety Assessment Methodology (SAM) v2.1. Nov 2006.

8 EUROCONTROL - Safety Regulatory Requirement 4 (ESARR4), Risk Assessment and Mitigation in ATM. EUROCONTROL - Safety Regulatory Requirement 3 (ESARR3), Safety Management Systems by ATM Service Providers. EUROCONTROL document SAME: Safety Assessment Made Easier, Edition 1.0, 15/01/2010. EUROCONTROL document SAME: Safety Assessment Made Easier, Part 2 under development at the time of edition of this PSC. ICAO, Air Traffic Management, Procedures for Air Navigation Services, Document 4444, Fifteenth edition ICAO PANS-OPS - Procedures for Air Navigation Services - Aircraft operations, Document ICAO Annex 10 - Aeronautical Telecommunications, Volume IV Surveillance Radar and Collision Avoidance Systems, Edition 3. ICAO Airborne Surveillance Task Force "Airborne Surveillance Manual" presently under development EUROCAE ED-160 Safety, performance and interoperability requirements document for ATSA-VSA Application, November EUROCAE ED-78A / RTCA DO Guidelines for approval of the provision and use of Air Traffic Services supported by data communications. December EUROCAE ED-125 Process for specifying Risk Classification Scheme and deriving Safety Objectives in ATM (March 2010). EUROCAE ED-126 / RTCA DO-303, Safety, Performance and Interoperability Requirements Document For ADS-B-NRA application, December RTCA DO-242A Change 1 published December 13, 2006, to DO-242A, Revision A: published June 25, 2002 as, ADS-B MASPS. Commission Regulation (EC) No. 2096/2005 of 20 December 2005 laying down common requirements for the provision of air navigation service. Commission Regulation (EC) No. 1315/2007 of 8 November 2008 on safety oversight in air traffic management amending Commission Regulation (EC) No. 2096/2005. EUROCONTROL Cascade Operational Focus Group - Use of ADS-B for Enhanced Application of Own Visual Separation by Flight Crew on Approach (information leaflet for ATCOs) (ATSA-VSA) Edition Number: 1.0 dated 1 December EUROCONTROL - Flight Crew Guidance for Enhanced Visual Separation on Approach, Edition Number: 1.0 dated 1 Dec 2008 EUROCAE ED-194, Airborne Surveillance Application (ASA) MOPS. In progress and expected to be published Q IFATCA Proposed material for the 2012 IFATCA Conference, IFATCA Technical and Operations Committee (TOC) working paper on "visual separation on approach". No provision yet for EASA material for "ADS-B IN" A-CNS Certification Specification ( *** )

9 2011 The European Organisation for the Safety of Air Navigation (EUROCONTROL) This document is published by EUROCONTROL for information purposes. It may be copied in whole or in part, provided that EUROCONTROL is mentioned as the source and it is not used for commercial purposes (i.e. for financial gain). The information in this document may not be modified without prior written permission from EUROCONTROL.