An unmanned aerial vehicle (UAV) or uncrewed aerial vehicle,^[1] commonly known as a drone, is an aircraft without a human pilot on board. UAVs are a component of an unmanned aircraft system (UAS), which include additionally a ground-based controller and a system of communications with the UAV.^[2][3] The flight of UAVs may operate under remote control by a human operator ― remotely-piloted aircraft (RPA)^[4] ― or with various degrees of autonomy, such as autopilot assistance, up to fully autonomous aircraft that does not allow human intervention.^[4]