PRELIMINARY SAFETY CASE

Transcription

1 SRC POSITION PAPER E U R O C O N T R O L PRELIMINARY SAFETY CASE Automatic Dependent Surveillance Broadcast, Non Radar Areas (ADS-B-NRA) Version 1.1, dated 12 December 2008 Edition February 2009 Released Issue

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3 Position Paper and Advice to States PRELIMINARY SAFETY CASE Automatic Dependent Surveillance Broadcast, Non Radar Areas, (ADS-B-NRA) Version 1.1, dated 12 December, This Position Paper presents the outcome of the review of the CASCADE Programme ADS-B NRA (Automatic Dependent Surveillance Broadcast for Non Radar Areas) Preliminary Safety Case, (PSC) conducted by representatives of NSA/Member States in the SRC Coordination Group, upon a mandate given by the SRC at the Thirty Third meeting of the Safety Regulation Commission held on 01/02 October 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 (hereafter referred to as PSC ) for Automatic Dependent Surveillance Broadcast in Non-Radar Area presents a credible set of generic arguments for the safe provision of Air Traffic Services, including radar-like separation, using ADS-B surveillance in Non Radar Areas. ANSPs choosing to deploy ADS-B in NRA will need to develop their own 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 an example set of Arguments in the form of Goal Structuring Notation that can be re-used by ANSPs when developing their local Safety Cases. Where attention to the key issues identified and attached to this Position Paper has been made, the SRC consider the PSC for ADS-B in NRA a valuable information, document for ANSPs to use as a starting point for their safety assessment of ADS-B in NRA. SRC Advice The SRC reminds States that the operational context for the NRA application is in areas where radar surveillance currently does not exist. Areas where ADS-B and radar will provide overlapping coverage will be covered by the ADS-B-RAD application. The PSC sets out a generic argument to support ADS-B in NRA. However, ANSPs choosing to deploy ADS-B in NRA are responsible to develop their own Local Safety Case and cannot rely on the PSC. Guidance Material is developed throughout the PSC to identify the issues that need to be addressed at the local level. Several key 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 in their local safety case

4 States will need to consider the implications of partial aircraft equipage at a local level and assess the impact upon: airspace organisation and sector modifications; the requirement for mandates (regional and cross-border) for aircraft certification, or airspace/route segregation. The benefits of ADS-B are dependent upon appropriate equipage - meaning that aircraft will need to be certified to the appropriate level. States may have to consult on a regional basis to achieve commonality of approach in aircraft certification where possible. The SRC reiterates that the determination of the separation minima to be used in ADS-B NRA remains the responsibility of the competent authority. The use of 3nm and 5nm in this PSC is linked to the corresponding technical performance specifications required to support such separation minima and should not be construed as advocating 5NM or 3NM. At the time of writing, ICAO does not consider separation minima lower than 5 NM for ADS-B NRA. For this reason, all requirements related to 3 NM separation service in this document are provided as an input to the ICAO process. The SRC recognises that the use of a single Mode A/C SSR as sole surveillance means is subject to the approval of individual States. The use of the reference radar as a basis for comparative assessment should be made according to each individual State s criteria. The SRC notes that the generic safety assessments for ADS-B NRA are based on hazards comparable to those that could occur in a radar environment. The SRC urges States to consider that new technologies may create as yet unidentified hazards. The SRC recommends that States and implementers avail themselves of ADS-B monitoring data repositories and facilities to support any transition to ADS-B NRA operations, and to fulfil their safety oversight responsibilities. For aircraft subject to EASA certification, AMC applies. It will be Member States responsibilities to promulgate appropriate airspace requirements so that other aircraft are compliant with relevant specifications. It should be noted that when applicable, the SPI Implementing Rule will require a higher certification level (target date 2015 for retrofit). States should be aware of their responsibilities regarding air traffic controller licences and competencies following the introduction of ADS-B: e.g. there will be a requirement for new ratings for the ADS-B airspace, conversion training for controllers already qualified on radar, or training for procedural controllers to obtain radar-like skills. Several key 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 in their local safety case. Like 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 planned deployment of this technology demands that this issue be addressed pro-actively. The likelihood and severity of interference will need to be considered by States when implementing ADS-B NRA, as will appropriate mitigation strategies such as procedural, legal or technical measures. As full disclosure of threats and counter measures is inappropriate in an open forum the SRC invites States to note that the EUROCONTROL CASCADE Programme is working closely with security experts in the development of a Security Safety Case.

5 Applicable Regulations and Standards for ADS-B-NRA At the highest level of regulation, all surveillance equipment and systems in the European Union are legally obliged to comply with the Single European Sky Essential Requirement (ER) for surveillance. Standards and manuals established for ADS-B-NRA to be used by States and ANSPs when considering implementation are: EASA AMC EUROCAE standard ED-126 (RTCA DO-303), Safety Performance and Interoperability Requirements Document for the ADS-B-NRA Application; PANS-ATM DOC4444, Edition 15, 2007, procedures and separation minima of 5 nm ; Annex 10 (Volume III & V) Aeronautical Telecommunications Related Regulatory Requirements CS/FAR , , , , , , or equivalent requirements of CS 23, 27 and 29, if applicable. EU-OPS 1.230, 1.420, 1.845, 1.865, 1040, and , as amended, or, if applicable, equivalent requirements of JAR-OPS 3. National operating regulations. Related EASA/JAA TGL/AMC (and FAA TSO) Material ETSO-2C112b: Minimum Operational Performance Specification for SSR Mode S Transponders (adopts ED-73B) ETSO-129A (TSO-129/TSO-129A): Airborne Supplemental Navigation Equipment Using the Global Positioning System (GPS) ETSO-145/ETSO-146 (TSO-145/TSO-146; TSO-145A/TSO-146A): Airborne Navigation Sensors Using the Global Positioning System (GPS) Augmented by the Wide Area Augmentation System (WAAS) AMC Certification of Mode S Transponder Systems for Enhanced Surveillance JAA Temporary Guidance leaflet (TGL) 13, Revision 1: Certification of Mode S Transponder Systems for Elementary Surveillance Related FAA Advisory Circular Material FAA AC20-138A: Airworthiness Approval of Global Navigation Satellite System (GNSS) Equipment At the time of this assessment, no gaps in legislation were identified by the SRC.

6 European Organisation for the Safety of Air Navigation EUROCONTROL March 2009 This document is published by EUROCONTROL in the interests of information. It may be copied in whole or in part, providing that EUROCONTROL is acknowledged as the source. The information contained in this document may not be modified without prior written permission from EUROCONTROL.