Aviation accident investigation analysis methodologies used by 12 government Safety Investigation Authorities

• ICAO analysis requirements in Annex 13 for aviation investigation do not specify the analysis methodologies to be used. • 12 leading Government Safety Investigation Authorities (SIAs) shared details of their analysis methodology usage. • All participant SIAs’ written and interview data demonstrated use of multiple systemic methodologies of varying complexity. • SIA analysis methodology usage was broader and more contemporary than in ICAO guidance or implied by some New View authors. • ITSA SIA investigation analysis better practice can inform other safety investigators and differing high-risk activities. Introduction : Leading government Safety Investigation Authorities (SIAs) that investigate major aviation accidents are members of the International Transportation Safety Association (ITSA). Investigation analysis methodology details are rarely included on SIA websites, in final accident reports, shared with peers, or specified by the International Civil Aviation Organization (ICAO). Some ‘New View’ safety researchers assume SIAs don’t use systemic methodologies and that accident investigation has little value. Because of the sensitivity of SIA work and need to prioritize safety value from available investigation funding, there has been little academic research on choice and use of investigation analysis methodologies to address these issues supported by SIAs or involving multiple SIAs. Method : Investigation analysis methodologies were defined broadly to include SIA-used academic models and ‘bespoke’ investigation processes. Over several years we gained the trust of 12 ITSA SIAs to provide written and interview data to address four research questions. NVivo12 software supported interview thematic analysis. Results : Ten SIAs reported using Rasmussen-based methodologies, 7 Reason-based, 6 own bespoke methodologies, 5 BowTie, 5 more recent systemic methodologies such as CAST and FRAM, and 10 SIAs used other methodologies such as SHELL, 6M, and bespoke methodologies from other ITSA SIAs. Conclusions : Multiple investigation analysis methodologies were used by all SIAs, sometimes in the same investigation. In contrast with aging ICAO publications and negative New View claims, the SIA research data illustrates choice and usage of complex systemic and less complex analysis methodologies in varying investigative contexts. Practical applications : The research is being used by the 12 SIAs to better understand, and draw from, each other. It has broad relevance for updating ICAO documentation that is now underway, for other SIAs and the wider aviation community, and for other high-risk industries that seek to understand professionally operationalized methodologies used for investigation, analysis, and safety action with associated learning.