Pilots performance and flight safety: the case of cognitive fatigue in unpressurized aircraft cabins

The purpose of this study is to understand the impact, evolution and perception of cognitive fatigue as a contributory factor on the occurrence of incidents and accidents, on unpressurized aircraft. This study use the science principles present in the Fatigue Management Guide for Airline Operators (FMG) [1] to evaluate data obtained by four methods of measuring cognitive fatigue [2] These consist in two objective measures, Psychomotor Vigilance Test (PVT) and an actiwatch (Readiband 5), and two subjective measures Samn-Perelli 7-point fatigue Scale (SPS) and sleep diaries. It is also obtained results from a survey related to this theme. From this research are draw conclusions of the influence and evolution of cognitive fatigue on the operations of unpressurized aircrafts and it is understood the difference between perceived cognitive fatigue and the real cognitive fatigue accumulated by the pilot. Is also drawn findings from a launched survey related to this theme. In this case study the focus will fall upon general aviation where there are no way to control and monitor the fatigue element, the cause of most incidents and accidents that occur in Portugal as concluded by analyzing several GPIAAF final reports using HFACS [3]. Normally this type of research is conducted within airline operators, that are already a very restricted and controlled domain of civil aviation, instead of within general aviation.