Flying machines are never to be flown near cables. It's not like human pilots on a helicopter can detect and avoid the cables in the first place.
Long-distance transmission wires are sometimes inspected with helicopters, so I guess there are exceptions and protocols, but outside those, flying machines just aren't supposed to fly near cables except for explicit intent to catch them. Especially across or under. You may only approach in slow parallel motions and/or back off.
Contra this assertion, drones are already frequently used around power lines, and as such, "finding hanging wires with a drone" is actually a very active field with fairly robust solutions. Not only are drones used for power line inspections (which are actually a somewhat easier variant of this problem, because the drone usually flies above or adjacent to the power lines in this scenario), but also for infrastructure inspections in direct adjacency to power lines. Power line detect-and-avoid is a headlining feature in one of DJI's newer enterprise platforms, the M400 (where it's based on LIDAR + mmWave Radar fusion).
Also of note, this isn't the first double-failure issue for the MK30 - they had an issue last year at their test facility where their LIDAR malfunctioned in the same way on two drones in the same weather condition (misting), the drones believed they were at 0.0AGL and powered down in flight.
My guess is that detecting wires is also a very active field of research in a military context unfortunately as nets become a common defense mechanism.
Yeah. Friend of mine was a news helicopter pilot and he had one of these systems that will cut a cable if you hit one by accident: https://www.youtube.com/watch?v=J6CsNqhAeeQ . Better than getting tangled, I guess.
It does protect, and is already certified and installed on many copters. Still, it's an emergency device, last resort, like parachutes on some small airplanes.
Here's an excellent video from Juan Browne around the challenges that wires present to aircraft operations [1]. Some of these are human factors for manned aircraft, like seeing a wire but then forgetting it's there, but one of his points is that it's simply safest to avoid flying below 1000ft AGL. That's not an option for drones today, and they presumably don't (yet) have the ability of humans to make inferences about the likelihood of cables near cranes and transmission line towers, making them particularly vulnerable.
That's not true, commercial and municipal drones operate above 400ft all the time. Non-commercial/civilian drones piloted by someone without an FAA Part 107 certification and a waiver cannot fly above 400ft. Also, you are allowed to fly 400ft -above- a vertical structure (like a tower) up to 1000ft tall to avoid exactly this type of collision as long as you are within 400ft horizontally of the structure.
EDIT: crud, I did not read your post carefully enough, sorry, you addressed this point exactly. My bad.
If you've ever driven through Seattle, as you come past Boeing Field on I5 there are red spheres on the power lines. These lines are on a hill across the highway from the airport, so there's no way any plane should be there except during an emergency landing due to power loss.
There are situations where aircraft and wires might come in close proximity. It's more accurate to say that be default we keep them way the hell away from each other, we make exceptions for special circumstances, and the exceptions tend to seem far more conservative than you would guess.
Long-distance transmission wires are sometimes inspected with helicopters, so I guess there are exceptions and protocols, but outside those, flying machines just aren't supposed to fly near cables except for explicit intent to catch them. Especially across or under. You may only approach in slow parallel motions and/or back off.