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The propulsion system with which drones fly in any direction or hover includes BLDC motors (Brushless DC motor), ESC (Electronic Speed Controller), and propellers. It varies according to the different types of platforms. In a quadcopter, the motor and propellers work in pairs with two motors & propellers placed alternatively one pair rotating clockwise (CW propellers), the other two motors rotate counter-clockwise (CCW Propellers). Similarly, in Hex three motors/propellers pair and in Oct four motors/propellers pair. These BLDC motors receive the electric signal from ESC which receives the signal from the flight controller which in turn receives the signal from the radio transmitter. Together they signal motor speed, braking, monitoring, and fault tolerance.

Apart, from this combustion-derived propulsion is also used in UAV mostly in a fixed-wing platform where some of them use a mini Turbojet engine to cruise at a higher speed. These fast jet mini UAVs have achieved speed as high as 700 km/h and even more. It uses ECU (Engine Control Unit) which comes along with actuators and some sensors and is directly connected to the fuel supply line of the combustion chamber to control the speed of the Turbojet engine.