Bayesian inference in Safety Compliance Assessment under conditions of uncertainty for ANS providers

• Published in: Safety science 2019-07, Vol.116, p.183-195, Article 183
• Main Authors: Arnaldo Valdés, Rosa, Gomez Comendador, Victor Fernando, Perez Castan, Javier Alberto, Rodriguez Sanz, Alvaro, Perez Sanz, Luis, Saez Nieto, Francisco Javier, Sanchez Aira, Eduardo
• Format: Article
• Language: English
• Subjects: Air navigation; Air traffic control; Air traffic management; Air travel; Airports; Assessments; Bayesian analysis; Decision making; Navigation systems; Occupational safety; Safety; Safety management; Safety margins; Statistical inference; Traffic management; Traffic safety; Uncertainty
• ISSN: 0925-7535; 1879-1042; 1879-1042
• DOI: 10.1016/j.ssci.2019.03.012

•Solves the issue of compliance for systems that lack data and operational history.•Avoid lack of operational data and uncertainty leading to erroneous conclusions.•Avoid system certification if not compliant with safety performance requirements.•Valid alternative to arbitrary Margins Of Safety (MOS) in the worst-case scenarios.•Inclusive handling of the uncertainties intrinsic to all System Safety Assessments. System Safety Assessment is an integral part of the design and operation of aviation and Air Traffic Management (ATM) systems. The aim of the System Safety Assessment is to identify, quantify and mitigate any and all risks; and to ensure that the system complies with the safety levels established by the regulatory authority. This paper presents an integrated methodology, based on Bayesian inference, for assessing and evaluating compliance with system safety requirements when there is uncertainty regarding the safety performance of ATM systems. The study constructs a Bayesian framework that reformulates the Safety Compliance Assessment as decision making under uncertainty. This framework addresses the main limitations of the System Safety Assessment carried out by Air Navigation Service Providers (ANSPs). Specifically, it:•Solves the issue of compliance for systems that lack the data and operational history of conventional systems.•Avoids situations under which limited information, lack of operational data and uncertainty may lead to erroneous conclusions and to the potential certification of a system that does not satisfy the minimum safety performance requirements.•Constitutes a valid alternative to the arbitrary Margins Of Safety (MOS) considered in the worst-case scenarios for safety assessments, thereby reducing the need for conservative assumptions and safety margins.•Allows for more inclusive handling of the uncertainties intrinsic to all System Safety Assessments. This leads to increased neutrality and a better understanding of decisions and judgements regarding compliance.The features and advantages of this approach are demonstrated via a case study which assesses whether an Air Navigation Service Provider (ANSP), which has begun to provide services at a new airport with new systems and technology, is compliant with the safety objectives. Specifically, it is necessary to demonstrate compliance with any and all safety requirements applicable to the Air Navigation Systems, in particular VOR, DME and ILS.