A Quantitative Study of Aircraft Maintenance Accidents in Commercial Air Transport

Aircraft maintenance is defined by the ICAO as the tasks that need to be carried out on an aircraft to ensure its continuing airworthiness. Accidents that result from aircraft maintenance activities are a direct measurable outcome that can be used to broadly assess the effectiveness of maintenance activities. This research seeks to understand the characteristics of aircraft-maintenancerelated accidents and how these have changed over time. An exploratory design was utilized, which commenced with a content analysis of 358 accidents from the Aviation Safety Network, followed by a quantitative ex post facto study. The results showed that aircraft-maintenance-related accidents were 1.7 times less fatal compared to all aviation accidents in the database. Fatalities were reduced significantly from the 1990s following major accidents with many fatalities; this was countered by several industry-wide initiatives. However, the number of accidents have continued to grow by one each year. Relative to all accidents, it was found that maintenance contributes to (2.0 +/- 0.4)% of all accidents, which increased to (3.8 +/- 0.7)% from 1998 to 2019, up from (1.3 +/- 0.2)% from 1941 to 1997. However, the rate of maintenance accidents per kilometer flown has decreased exponentially halving every 27.7 years. The results showed that the most common age of an aircraft involved in a maintenance accident was 5 to 15 years, corresponding to the first heavy maintenance period of an aircraft (6 to 12 years). Further results for age showed no correlation to the fatalness of accidents; however, older aircraft were more likely to be written off.