I dont know. There is definitely a flow of energy between the power line and the drone. But there is no closed circuit between them so there is no current flowing. I imagine there is a (slightly, almost not measureable) raised current in the powerline due to a lower resistance due to the parasitic voltage drop and phase shifting cause by the inductive load. So technically no current between the drone and the powerline. Although there is energy transfer. But there are probably lots of people here that understand the laws of electromagnetism a lot better than me.