I refuse Frank's reasonable explanation for why this is safe, and instead choose to believe that it's safe because adding helicopters, chainsaws, and powerlines together causes an overflow in the danger variable and wraps it back around to near 0.
I trust that helicopter pilot more than I trust tesla drivers.
Relatively little. The helicopter isn't grounded and I've fairly certain they can quick-disconnect the saw.
Just one example - what if the pilot makes a mistake and sends the saw into the power lines?
I'm 90% certain there's a button to drop the saw instantly. And the power won't route through the helicopter bc it's not grounded, whereas pretty much any ground based equipment would ground the current if it touched the wire.
They use these across tens of thousands of miles of power easements all the time. The easements need regular pruning to keep branches from touching the wires and starting electrical fires.
I know nothing about this, but I would imagine it's not a button, its likely mechanical. If the safety circuit detects an arc, the cable detaches.
If each of those wires are carrying multiple phases or voltages, the saw could initiate an arc between the wires.
https://youtu.be/gOT8jx4jEzM?t=109 (skip to the 1:50 mark to see an example of a phase-to-phase arc)
Squirrel family perched on a branch: do you guys hear something?
Not as easy as you'd think for transmission lines. California has one and it cost something like $10mil to fix a fault. The whole thing has to be filled with pressurized mineral oil with no impurities and each conductor needs to be wrapped in tons of layers of paper. The fault was caused because ground shift tore some of the paper and shorted the phases.
They had to literally freeze the pipe with liquid nitrogen to form makeshift plugs out of frozen oil to work on it.
Compare that to overhead where you can just send a random guy out there to walk it and say "yup, looks good" and worst case you drop a dude on the line from a helicopter.
Edit: Looking at the video again, those are fucking distribution poles. They absolutely shouldn't be using this equipment by distribution lines, the span distance isn't long enough and the treeline clearance isn't far enough. One snag and they're killing power for the town.
wow I had no idea about the pressurized mineral oil. and yeah after I posted this I realized how hard it would be to trench over dozens of miles of rocky mountain areas. sinking poles is several orders of magnitude easier
Yep, another bonus of poles is rent. Power companies can charge rent to telecoms that want to attach to their poles. Can't charge rent on a hole (though there are some kinda trying by pulling extra conduit and selling it to ISPs)
now I've been reading about all the operational reasons for why the oil is there. very interesting, also apparently an environmental hazard after the line is decommissioned
Yeah, it's really not a good idea. They only put it in because of NIMBYs. Ironically they all now have a n environmental hazard waiting to happen in their back yards instead of a few high voltage pylons.
Wacky Wonder Saw coming to Steam Early Access this year.
A crane is grounded so if it hits the lines a current can flow through it. It's too slow to effectively do large sections of these easements which are often on rough terrain.
This is as dangerous as any helicopter operation, but it's not as insane as it looks at first glance.
i suspect it's also further away from the lines than we might think
No, it's pretty much as close to the lines as it looks like. Have you ever seen these easements? They're not that wide lol