This project examines the safety management of civil aircraft accident investigation authorities in International Civil Aviation Organization (ICAO) Member States, with particular emphasis on the independence of the investigations. The research aims to establish the current level of resources and methodology adopted by Member States’ accident investigation authorities. The output of this work not only identifies the current situation but informs initiatives for some of the States in the process of establishing their investigation capability. ICAO Annex 13 was analysed and found to be based on the principle of independent accident investigations. Also, a four dimensional measuring index (4DMI) has been developed to measure the independence of accident investigations in ICAO Member States. Data were collected from 45 States and are presented in the thesis. As a result of applying the 4DMI to the collected data, the States were ranked according to their scores, and divided into four categories of independence. Analysis of the four categories and the scores from the four dimensions revealed that States approach the concept of investigation independence in different ways; however, there are several practices that are common within the highest independence category and several other practices that are common within the lowest independence category. The research recommends that States should work towards improving their overall investigation independence by implementing the seven identified practices in the High-Independence category and distance themselves from the five practices identified as common in the Low-Independence category.

This project examines the safety management of civil aircraft accident investigation authorities in International Civil Aviation Organization (ICAO) Member States, with particular emphasis on the independence of the investigations. The research aims to establish the current level of resources and methodology adopted by Member States’ accident investigation authorities. The output of this work not only identifies the current situation but informs initiatives for some of the States in the process of establishing their investigation capability. ICAO Annex 13 was analysed and found to be based on the principle of independent accident investigations. Also, a four dimensional measuring index (4DMI) has been developed to measure the independence of accident investigations in ICAO Member States. Data were collected from 45 States and are presented in the thesis. As a result of applying the 4DMI to the collected data, the States were ranked according to their scores, and divided into four categories of independence. Analysis of the four categories and the scores from the four dimensions revealed that States approach the concept of investigation independence in different ways; however, there are several practices that are common within the highest independence category and several other practices that are common within the lowest independence category. The research recommends that States should work towards improving their overall investigation independence by implementing the seven identified practices in the High-Independence category and distance themselves from the five practices identified as common in the Low-Independence category.

Human - Technology - Organization (HTO) is a well-established, general unifying concept in the Swedish Accident Investigation Authority (SHK) that represents an approach, knowledge and use of various tools regarding interactions between people, technology and organizational factors. The HTO-perspective is well described in literature but there are few studies on how SHKs staff experiences working according to this method in their investigations. The aim of this study was therefore to describe their HTO-perspective, examine how it is used in the investigations at SHK and describe the investigators experience of working with the HTO-perspective as well as the method's usefulness compared to old methods in accident investigations. A literature study has been conducted in the areas of HTO, Theory of planned behavior (TPB) and safety culture. TPB and safety culture are described in this paper since they highlight the different aspects of a HTO-perspective. The hypothesis was answered by using semi-structured interviews. The interviews were analyzed by a content analysis and themes were identified. Furthermore the material from the interviews was subsequently structured through a Strength – Weakness – Opportunities – Threats analysis (SWOT), i.e. the informants' view on the HTO-perspective was structured based on the strengths, weaknesses, opportunities and threats SHKs staff experience that the method has in the investigative work. The informants consisted of two investigators at SHK who 3have worked with accident investigations for a long time in various roles. The results yielded that the investigators had a positive attitude towards conducting investigations according to the HTO-perspective because they feel that this perspective provides them with cross-competence. A flaw is though that the perspective lacks a structured approach. As a result of this, the investigators own experiences and expertise play a major role in the quality of the investigation. As the study's aim is met and the informants are considered to be experts the validity requirements are also fulfilled.