11 ms·

This video shows an aerial line crew (lineworker and pilot in a helicopter) bypassing a high-resistance splice in a 220kV overhead power line, attaching a large

This video shows an aerial line crew (lineworker and pilot in a helicopter) bypassing a high-resistance splice in a 220kV overhead power line, attaching a large bolt-on shunt while the line is still live. The lineworker sits on a platform on the outside of the helicopter while doing the work, in an incredible demonstration of precision helicopter hovering.

laumars 8y ago
I've been having a stressful week (thus far) at work and this video really puts things into perspective.
- mchahn 8y ago
  That lineman deserves a raise, no matter what he makes. He falls in the category of workers who are lowered into nuclear reactors to cleans things up.
sevensor 8y ago
I saw a crew like this at work once. No idea what they were working on, but they were doing it to lines that crossed over the highway I was driving on. I was moving at highway speed, so my mind didn't really have a chance to boggle until I was already past. Those helicopter pilots must have a very steady hand.
- ableal 8y ago
  > very steady hand I don't know the first thing about helicopters, but the negative feedback circuits that keep things steady in many applications, from power supply voltages to Segways, could help with that. It's a very simple basic concept that has been around for many decades, even before analog electronics, never mind digital devices: https://en.wikipedia.org/wiki/Negative_feedback https://en.wikipedia.org/wiki/Negative_feedback (I repeat I do not know if they are available in helicopters. It may well be the pilot doing it by hand the hard way.)
  - rzzzt 8y ago
    Search-and-rescue helicopters are the most likely to have that capability: https://en.wikipedia.org/wiki/AgustaWestland_AW139#Design https://en.wikipedia.org/wiki/AgustaWestland_AW139#Design https://en.wikipedia.org/wiki/Eurocopter_HH-65_Dolphin#Design https://en.wikipedia.org/wiki/Eurocopter_HH-65_Dolphin#Desig...
  - halbritt 8y ago
    Computerized stability control systems exist, are quite prevalent, and have a thriving open source community. Check out: https://github.com/betaflight/betaflight/wiki https://github.com/betaflight/betaflight/wiki Granted, it's for hobby scale drones, but the same principles apply.
    - dfox 8y ago
      The physics involved in multi-rotor drones (or even counter rotating dual rotor toy-level RC helicopters) is significantly different from single rotor+stabilizer helicopters in that there is at least in theory point where the thing is dynamically stable.
      - bri3d 8y ago
        For what it's worth many toy RC helis exist with collective pitch tail rotor setups and full feedback stabilization - it started with tailrotor yaw hold automation and now they can stabilize in all axes. Check out something like Blade mCPx
        gjhan 8y ago
        The dynamics, which are not just the rigid body dynamics plus the aerodynamics of the vehicle but also include many structural modes of the rotorhead and blades, are not scale invariant. An RC helicopter is proportionally stiffer in certain degrees of freedom by an order of magnitude (in rotor angular velocity and thrust:weight ratio e.g.), and so can ignore dynamical factors that dominate the control and structural sizing for manned helicopters.
- pdkl95 8y ago
  > Those helicopter pilots must have a very steady hand. Piloting a helicopter in general requires an incredibly steady hand on unintuitive controls that interact with each other in ways that are difficult to predict[1]. Being able to do that with high precision, a disturbingly small margin of error, and fatal consequences for almost any error is basically a superpower. [1] SmarterEveryDay has an interesting video[2] about learning to hover a helicopter, which apparently requires trying to hover (badly) until the brain learns how to abstract away all of the complexity. [2] https://www.youtube.com/watch?v=eXR1olg_I0w https://www.youtube.com/watch?v=eXR1olg_I0w
lisper 8y ago
It is hard to overstate how difficult it is to hover a helicopter this precisely for this long. Helicopters are dynamically unstable. If you take your hands off the controls, they start to flip over almost immediately and become unrecoverable within 2-3 seconds. The best analogy I've heard: imagine trying to stand on a basketball. Now imagine trying to stand on a basketball without flailing your arms around. Now imagine trying to do that for half an hour while someone's life depends on you not screwing up even for a single second.
- chrischen 8y ago
  They can’t do computer based stabilization?
  - lisper 8y ago
    Auto-hover technology does exist, but it's not common. Also the pilot has to be able to do it manually in case the autopilot fails, and so most pilots will elect to do it manually at least some of the time just to stay in practice.
    - dogma1138 8y ago
      Isn’t AFCS with hold position capability pretty much standard these days?
      - lisper 8y ago
        No. https://www.reddit.com/r/flying/comments/998c8b/helicopter_pilots_how_common_is_afcs_nowadays/e4lrcay/ https://www.reddit.com/r/flying/comments/998c8b/helicopter_p...
    - tinus_hn 8y ago
      Perhaps the smart thing would be to practice in situations where an error does not cause someone else to get electrocuted.
tkahnoski 8y ago
A year or two back they recently did maintenance on a majority of the high voltage towers in the greenway behind my house. They sent out flyers to all the residents a few days ahead. This video shows once splice. I can't imagine the crew (or crews) that were working the miles of lines behind our house doing this for multiple days in a row.
- londons_explore 8y ago
  This kind of splice repair should be rare. It only needs doing when the original splice was badly done.
liareye 8y ago
230kv
trumped 8y ago
I just watched it... this feels like deja-vu...

laumars 8y ago

I've been having a stressful week (thus far) at work and this video really puts things into perspective.

mchahn 8y ago
That lineman deserves a raise, no matter what he makes. He falls in the category of workers who are lowered into nuclear reactors to cleans things up.

sevensor 8y ago

I saw a crew like this at work once. No idea what they were working on, but they were doing it to lines that crossed over the highway I was driving on. I was moving at highway speed, so my mind didn't really have a chance to boggle until I was already past. Those helicopter pilots must have a very steady hand.

ableal 8y ago
> very steady hand I don't know the first thing about helicopters, but the negative feedback circuits that keep things steady in many applications, from power supply voltages to Segways, could help with that. It's a very simple basic concept that has been around for many decades, even before analog electronics, never mind digital devices: https://en.wikipedia.org/wiki/Negative_feedback https://en.wikipedia.org/wiki/Negative_feedback (I repeat I do not know if they are available in helicopters. It may well be the pilot doing it by hand the hard way.)
- rzzzt 8y ago
  Search-and-rescue helicopters are the most likely to have that capability: https://en.wikipedia.org/wiki/AgustaWestland_AW139#Design https://en.wikipedia.org/wiki/AgustaWestland_AW139#Design https://en.wikipedia.org/wiki/Eurocopter_HH-65_Dolphin#Design https://en.wikipedia.org/wiki/Eurocopter_HH-65_Dolphin#Desig...
- halbritt 8y ago
  Computerized stability control systems exist, are quite prevalent, and have a thriving open source community. Check out: https://github.com/betaflight/betaflight/wiki https://github.com/betaflight/betaflight/wiki Granted, it's for hobby scale drones, but the same principles apply.
  - dfox 8y ago
    The physics involved in multi-rotor drones (or even counter rotating dual rotor toy-level RC helicopters) is significantly different from single rotor+stabilizer helicopters in that there is at least in theory point where the thing is dynamically stable.
    - bri3d 8y ago
      For what it's worth many toy RC helis exist with collective pitch tail rotor setups and full feedback stabilization - it started with tailrotor yaw hold automation and now they can stabilize in all axes. Check out something like Blade mCPx
      - gjhan 8y ago
        The dynamics, which are not just the rigid body dynamics plus the aerodynamics of the vehicle but also include many structural modes of the rotorhead and blades, are not scale invariant. An RC helicopter is proportionally stiffer in certain degrees of freedom by an order of magnitude (in rotor angular velocity and thrust:weight ratio e.g.), and so can ignore dynamical factors that dominate the control and structural sizing for manned helicopters.
pdkl95 8y ago
> Those helicopter pilots must have a very steady hand. Piloting a helicopter in general requires an incredibly steady hand on unintuitive controls that interact with each other in ways that are difficult to predict[1]. Being able to do that with high precision, a disturbingly small margin of error, and fatal consequences for almost any error is basically a superpower. [1] SmarterEveryDay has an interesting video[2] about learning to hover a helicopter, which apparently requires trying to hover (badly) until the brain learns how to abstract away all of the complexity. [2] https://www.youtube.com/watch?v=eXR1olg_I0w https://www.youtube.com/watch?v=eXR1olg_I0w

lisper 8y ago

It is hard to overstate how difficult it is to hover a helicopter this precisely for this long. Helicopters are dynamically unstable. If you take your hands off the controls, they start to flip over almost immediately and become unrecoverable within 2-3 seconds. The best analogy I've heard: imagine trying to stand on a basketball. Now imagine trying to stand on a basketball without flailing your arms around. Now imagine trying to do that for half an hour while someone's life depends on you not screwing up even for a single second.

chrischen 8y ago
They can’t do computer based stabilization?
- lisper 8y ago
  Auto-hover technology does exist, but it's not common. Also the pilot has to be able to do it manually in case the autopilot fails, and so most pilots will elect to do it manually at least some of the time just to stay in practice.
  - dogma1138 8y ago
    Isn’t AFCS with hold position capability pretty much standard these days?
    - lisper 8y ago
      No. https://www.reddit.com/r/flying/comments/998c8b/helicopter_pilots_how_common_is_afcs_nowadays/e4lrcay/ https://www.reddit.com/r/flying/comments/998c8b/helicopter_p...
  - tinus_hn 8y ago
    Perhaps the smart thing would be to practice in situations where an error does not cause someone else to get electrocuted.

tkahnoski 8y ago

A year or two back they recently did maintenance on a majority of the high voltage towers in the greenway behind my house. They sent out flyers to all the residents a few days ahead. This video shows once splice. I can't imagine the crew (or crews) that were working the miles of lines behind our house doing this for multiple days in a row.

londons_explore 8y ago
This kind of splice repair should be rare. It only needs doing when the original splice was badly done.

liareye 8y ago

230kv

trumped 8y ago

I just watched it... this feels like deja-vu...