The first test of a 64mm electric ducted fan (EDF) with a 30A ESC.
The tests tries to asses whether the fan is balanced properly.
For the first 11s the power is very low (almost at minimum) and for the rest of time the power is a bit higher.
In the second part (from 11s on) I am also squeezing the fan's case between my fingers from time to time: you can hear that the propeller blades seem to rub against the inner surface of the case.