It looks to me like something designed to filter motor noise (servos, brushed or brushless main motor) out of the power going to the sensitive RF components (receiver, etc)
With the components shown (100uF caps, 1000uH inductor), you should get a low-pass filter with a cutoff frequency of about 700 Hz. Higher frequencies would be filtered out too (more, in fact), up to practical limits of the components (which are going to be very real, once you get to RF frequencies.)