In theory, it should be posible to recharge from them while in flight by creating one half of a transformer coil & a rectification circuit, then flying parallel to the wire. The closer you get, the more efficient the transformer would work. However, to get a precise charge, you would need to calculate the right number of turns in your "transformer" coil based upon the voltage in the wire, the distance between the wire and the plane, and the speed of the plane.

Want a faster charge? Fly closer... I don't intend to test this theory though.

Aeronaut : Most of our electricity here comes from Hydro-Electric power dams, so we call the poles "Hydro Poles". Hence my friend's nickname "Hydro".

As chance might have it, this same site also had the high power transmission lines along-side it, about 600 feet away. We never experienced any RF interference from them, but maybe we just got lucky. I personally have had a plane get about 100 feet from the high power lines, without glitching, using an AM radio, due to a brief loss of depth perception while avoiding a suicidal pilot's plane (he almost hit himself with his own plane while trying to land).