Just imagine your drone produces infuriating noises. Do you know why? It is because of the BLDC motors and the propellers, right? But theoretically, drones should not make that much loud a noise. Can you imagine why? Because of the proper uses of the aerodynamics inside a drone. The physics for flying a drone is really necessary to be known by all the drone pilots because, if you cannot master the air, your drone will not fly properly. Refer to the following figure to get a rough idea on how air is effected by the propellers of the drone.
The figure is taken from the NASA website. They simulated the aerodynamics via computers:
So, basically a drone (specially quadcopters) has two pairs of propellers ...
