Abstract
The purpose of this study was to explore the role of cognitive bias in the flight deck of
commercial aircraft through historical aviation accident and incident reports, to establish the
most common types of biases and whether a set of pre-existing conditions in the flight deck
environment influence their presence during critical events. The role of cognitive biases in
aviation decision making is of growing interest and their impact is noted in this study as their
role in some of aviation’s biggest disasters and near misses in the past 15 years is revealed.
The research on cognitive bias applied to this setting is somewhat in its infancy, with little
research on what elements in the flight deck influence bias. A mixed methods approach was
adapted, and content analysis was applied to quantitively measure the qualitative data
contained in 25 official commercial aviation accident and incident reports in which cognitive
bias was mentioned in the report as having affected or influenced the crew. The Bowtie risk
analysis framework, which is a model to establish causal relationships in high-risk scenarios,
was adapted and provided structure to the data collection and analysis. Several
characteristics pertaining to the flight crew, the operation and the environment were collected
and analysed for each report, alongside the types of biases present and the outcome detailed
in the report. This study revealed that cognitive bias disproportionally involved more
accidents than incidents during conditions that tended to be more favourable than not. The
flight crew were experienced and disproportionately not suffering from fatigue, with the
captain occupying the pilot flying role more frequently. Certain biases were found to be more
present at different phases of flight and there was disproportionally no aircraft malfunction
during the events analysed. Cognitive bias also didn’t appear to discriminate between
daylight or darkness, good or poor weather conditions. This research provides valuable
insight into the impact of cognitive bias on flight safety and reveals some of the conditions
under which cognitive bias thrives in the environment of commercial aircraft. This study sets
the foundations for future research which should focus around developing supporting flight
crew with debiasing education and techniques to further improve the safety of the industry.