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An initial parametric study of weight and energy thresholds for falling unmanned aerial vehicles (UAVs)

In recent years we have seen a considerable rise in the demand for the use of UAVs (unmanned aerial vehicles, or drones as commonly called) in commercial, public service and leisure applications. It has subsequently resulted in an increase of media reports on incidents due to small civil drones, particularly about small civil drones, particularly in cases where they have collided with structures and/or people on the ground. These incidents exemplify the potential danger associated with UAV operations in populous areas. However, not all collisions had resulted in fatal injuries. Different countries and agencies have set different weight limits for civil drone operations with neither much elaboration nor scientific evidences clearly provided. It is therefore useful that a study of minimum weight thresholds for drone operations could be conducted. The findings and results can serve as an appropriate advisory for policy and regulations. Therefore, in this work, the effect of drone's weight associated with the height limit is investigated by virtue of the basic principle of mechanics. The effect of the weight and height to the impact energy, based on the established probability model, is also studied and presented with the results obtained.