Document Type

Journal Article

Publication Title

Safety Science






School of Medical and Health Sciences




Bills, K., Costello, L., & Cattani, M. (2023). Major aviation accident investigation methodologies used by ITSA members. Safety Science, 168, 106315.


The International Civil Aviation Organization (ICAO) Annex 13 framework for aviation investigation is longstanding and well developed but does not require or audit use of methodologies for investigation analysis, including research literature safety/accident models (SAMs). Government Safety Investigation Authority (SIA) websites rarely mention methodologies. Limited published research engages directly with SIAs. A research/practice gap has been suggested. To address ICAO, SIA and research gaps, this qualitative multi-case study examines SIA use and documentation of methodologies for accident analysis. Nine of seventeen SIA members of the International Transportation Safety Association (ITSA) that investigate aviation accidents agreed to participate and provided written answers to our research questions, relevant internal documentation, and exemplar investigation reports. Our key findings are that participant SIAs have augmented ICAO requirements internally by their use of methodologies but that this usage was generally not obvious in published investigation reports and other SIA website material. It also varied significantly among the participants. All participant SIAs reported use of multiple methodologies, sometimes in the same investigation. Explicitly reported SIA methodology usage included: six Reason-based, six Rasmussen-based, three ‘recent systemic’, five ‘BowTie’, five ‘bespoke’, and seven using various other methodologies like ‘SHELL’. The industry impact of this qualitative research is hoped to be significant by being shared with participant SIAs unaware of each other's practice, enabling consideration of different options. It can inform additional aviation SIAs, ICAO, air safety investigators, and other high-risk industry regulators and investigators. Safety researchers may be better placed to develop SAMs with greater practical industry relevance.



Creative Commons License

Creative Commons Attribution-Noncommercial 4.0 License
This work is licensed under a Creative Commons Attribution-Noncommercial 4.0 License