I was interested to see this footage of a helicopter using an underslung powered saw to trim tree branches near a power line.
It reminded me of a painful encounter with a nest of African wasps dislodged by a helicopter doing powerline clearance work in Southern Africa during the 1980's. The chopper wasn't using anything as sophisticated as that powered saw, but rather dragging a sort of grapnel, if I recall correctly - I don't know precisely why. Be that as it may, it hacked into a wasp nest, and the angry critters decided that anyone nearby must have had a hand in the desecration of their home. We ran pretty darn fast that day . . . in Army boots with full kit and rifle, at that!