Piloting the Pilotless: A Model for Stress in UAV Operators

Kurzfassung

This study, conducted in collaboration with the DLR - Institute for Flight in Braunschweig (Germany), focused on stress among operators of Unmanned Aerial Vehicles (UAVs) involved in surveillance, as well as in search and rescue (SAR) operations, in which pilots frequently encounter emergency situations. While the literature on stress in conventional aviation is extensive, the field of UAV missions remains relatively unexplored. This research addressed three primary research questions: unravelling the concept of stress within the UAV aviation context, defining the scope of stress assessment to determine the most suitable approach for the UAV setting and conceptualizing the underlying factors contributing to the stress experience. The thesis project was structured by combining two complementary studies. A descriptive review was conducted using the PRISMA method to address the concept of stress and its assessment in UAV operations. It followed an empirical study involving semi-structured interviews and a questionnaire with the purpose of depicting the stress experience from the operators’ perspective. The results of the descriptive review revealed two main clusters of findings: factors and mechanisms underlying stress in UAV setting and approaches to stress assessment. The first bundle included aspects about the unique nature of stress responses in this setting, the relationship with the concepts of workload and startle, the cognitive impact of stress and primary coping strategies. Trust in automation emerged as a key factor for stress in this domain: different levels of automation reliability lead to different intensities of stress effects. The second bundle provided a discussion on various methodologies for physiological and psychological stress assessment. A combination of objective and subjective (i.e., self-report) methods are suggested to meet the piloting setting limitations and ensure the measures’ validity. The empirical research, which involved semi-structured interviews (N=4) and a questionnaire (N=10), allowed for an in-depth exploration of the stress experience from the perspective of UAV pilots. The outcomes of this study were many across the themes of individual characteristics, stress beliefs, perceived safety, and coping strategies. A valuable finding regarded the operators' confidence in a series of skills. O one side participants showed high confidence in problem-solving and quick decision-making. On the other, it was observed low reliance on organizational and time management skills which are great contributors to stress. The integration of the studies has resulted in a theoretical model for stress in UAV operators describing the underlying mechanism of stress in this specific context. This model includes different factors and mechanisms: feedback, startle, cognitive appraisal, and controlled central cognitive processing, as well as protective factors. The iterative interaction of these elements can lead to either negative or positive stress loops which can be modulated by the shielding of protective factors such as apt training and thorough knowledge of the system’s procedures. In conclusion, this research, utilizing a mixed-methodological approach, may contribute to the development of knowledge in this specialized field. The descriptive review has provided a comprehensive review of stress in aviation. The combination of the review’s results with those of the empirical work has resulted in a theoretical framework that may be useful to enhance our understanding of stress experiences in this specific context. The implications of this project regard both a deeper understanding of the concept of stress in the setting of UAV operations and a conceptual framework applicable for informed planning of procedures, guidance for future training and increased awareness of stress underpinnings. Furthermore, the results of this research offer a basis for the future implementation of a multiphases approach to stress management in UAV operations.