okay so i know the obvious answer is dont fly near power lines but hear me out. im doing some survey work in a rural area and the site basically has high voltage transmission lines running right through the middle of it. we're talking the big ones, like 345kv lines on tall towers. i need to map the whole property including that section and im trying to figure out how much of a real world problem the EMI is going to be vs how much is just general caution advice that gets repeated without anyone actually testing it.

ive read stuff ranging from total compass freakouts at 50 meters to people saying they flew right under similar lines with no issues at all. running a Autel Evo II Pro, so no ocusync or anything proprietary, just standard 2.4/5.8ghz rc link. curious if anyone has actual experience with this specific scenario and not just general stay away advice

the compass interference is real but honestly the bigger thing people dont talk about is the induced voltage you can get on the aircraft frame if you get close enough. not relevant at normal survey distances but just something to be aware of. practically speaking for survey work i'd say 30-40 meters lateral clearance from the actual conductors is where most people feel comfortable, anything closer and you're really in unpredictable territory depending on line load and atmospheric conditions.

for the compass thing specifically you can switch to GPS only mode and disable mag assisted heading if your aircraft supports it, that removes one failure point. the 2.4ghz RC link isnt really what i'd worry about, power lines dont put out much in that band, its more the low frequency stuff that messes with magnetometers.

did a pipeline inspection job last year that had similar lines nearby and honestly the video link was completely fine. compass was doing some weird stuff when we got within maybe 20 meters but we werent going that close anyway. i think a lot of the horror stories come from people with older hardware or just assume worst case. that said i wouldnt push it, the survey can probably be done in sections without needing to be directly under the lines if you plan the flight lines carefully