Don't power lines generate a electric field that is equal to the power at the source times the square of the distance.
I guess I would not get to close. 100ft max, as I have experience getting shocks from power lines as they induced a small current into steel beams I was loading on a semi truck a long time ago.
yes bpl does cause interferance with 72 mgz ive been following the ama's fight with this thruogh congress.as far as i know they are not forceing the bpl companies to not interfear but the companies are volantaraly "knotching out " the 72 mhz band.
I think any serious UAV is going to use spread spectrum technology via 2.4Ghz Jr/Futaba/Spektrum/XPS or home made versions using 400,900,or 1.2Ghz radio modem systems. In addition, once the plane is airborne, your autopilot will be doing most of the work until it is time to land. I just don't see BPL interference as an issue any more then any other source of interference. If you need long range control, consider moving to 50Mhz and build an rf amp for 'emergency' control issues.
I just thought of something. Be careful of whatever frequencies you use for clock cycles in your controller systems. Microcontrollers have been getting higher clock speeds than they have in the recent past.
Actually we've been advising against 2.4 GhZ RC systems if you're using 2.4Ghz video downlinks, as is often the case. There have been some reports of clashes. That said, I'm not too worried about 72 Mhz problems---after all, unlike most RC planes, our birds are designed to fly home if they have radio dropout!