Fundamentals of Remotely Piloted Aircraft Systems (RPAS) is a comprehensive textbook that covers the foundational aspects of RPAS technology and its impact on aviation. Divided into five units, the book introduces key concepts and terminology related to RPAS, including their classifications and components. It explores the design and performance of robotic vehicles, with a focus on airborne vehicles, addressing aerodynamics, control, and stability. The book also provides an in-depth understanding of data links in RPAS, emphasizing reliability and security. It delves into ground control stations, their types, and roles while considering human-machine interaction. Lastly, the book explores RPAS payloads and their applications in remote sensing, covering imaging technologies and the importance of geospatial data accuracy. Overall, this textbook is a comprehensive guide for those interested in the evolving field of remotely piloted aircraft systems.