The first Aero-Train training school on Unmanned Aerial Systems for Inspection and Maintenance was held on March 7-10th at the University of Seville, Spain. The school provided theoretical knowledge and hands-on experience on design, control, planning, navigation, and state estimation for Unmanned Aerial Systems and aerial manipulators for Inspection and Maintenance. This school focused on providing the students with an overview of the technologies involved in the design, development and operation of UAVs and aerial manipulators. It also provided insights on implementing models, controllers and state estimators for UAVs in simulation. During the school, students were furthermore exposed to the aero-train network, where they had the unique opportunity to pitch their research projects to the industrial stakeholders of the project, get their feedbacks and new career perspectives.