How Do They Do It

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mdshunk

Senior Member
Location
Right here.
I think that's the one with Dan "Spider" Lockhart, the helicopter lineman with First Energy / Agrotors in Gettysburg, PA (just over the hill from me). He used to work for FPL, if I'm not mistaken.
 

dcspector

Senior Member
Location
Burke, Virginia
brian john said:
AS I surf the forums there is a new Science Channel show on electrical primary distribution, helicopter line men and substation operation.

Just watched that again this morning how they bond on from hi line to chopper. Yep Spider worked for FP&L Marc.
 

tkb

Senior Member
Location
MA
Pierre C Belarge said:
Is that the video where at the end he tells the audience the 3 things he is afraid of ?

It was the same flight as in the video, but parts of the video weren't in the show.

They has a guy replacing a spacer between the two parallel cables, and then Spyder crawled out on to the cables to install damping weights.

I had my wife watch it and told her that was my next job. :grin:
 

Rampage_Rick

Senior Member
tkb said:
It was the same flight as in the video, but parts of the video weren't in the show.

They has a guy replacing a spacer between the two parallel cables, and then Spyder crawled out on to the cables to install damping weights.
I'd love to see that additional footage...

Shows like that make me want to subscribe to American satellite...
 

j-box

Member
Location
texas
Rampage_Rick said:
I'd love to see that additional footage...

Shows like that make me want to subscribe to American satellite...

Does American satellite offer the NFL network?:confused: :grin:
 

ELA

Senior Member
Occupation
Electrical Test Engineer
480sparky said:

That was very interesting!

The equalization of charges being accomplished with the rod as the helicoper approaches and leaves the high lines was fantastic!

I know helicopers generate a static charge due to the rotors turning in air. My guess is that static charge is much lower than the high line voltage?
So, the helicoper is being charged up to the same level as the high lines on approach and this is what creates the large arc?

I would love to see a voltage reading of the helicoper body with respect to ground as it takes off, approaches the high lines and when it retreats and then back to ground.
 

LarryFine

Master Electrician Electric Contractor Richmond VA
Location
Henrico County, VA
Occupation
Electrical Contractor
ELA said:
So, the helicoper is being charged up to the same level as the high lines on approach and this is what creates the large arc?
What matters is the relative voltage difference between the two objects, not either object's absolute voltage to earth. The helocopter's charge would be DC, by the way.
 

ELA

Senior Member
Occupation
Electrical Test Engineer
LarryFine said:
What matters is the relative voltage difference between the two objects, not either object's absolute voltage to earth. The helocopter's charge would be DC, by the way.

I understand that the "potential difference" between objects is what is important. I was having a hard time putting my head around the large (what appears to be 2 ft or so) arc. I did not think that the helicoper "dc static charge" would be large enough to jump that gap (or be maintained for that long)?
So I am asking:

Is that large arc due to a static charge on the copter only?
 

zog

Senior Member
Location
Charlotte, NC
Nope, the line is at line voltage, the copter is at another, lets just assume 0V because it might as well be. As the worker approaches the line an arc is drawn to raise the rod, worker and platform to the line voltage, the current that flow is small because there is no path for current flow. The same thing occurs when racking in a MV breaker, thats the hiss you hear.
 

ELA

Senior Member
Occupation
Electrical Test Engineer
zog said:
the current that flow is small because there is no path for current flow. QUOTE]

No path? There must be some path.

Are you saying that the current flows due to capacitive coupling between the earth and the copter?

If so then why doesn't a bird fry when they approach the single line conductor?
 

zog

Senior Member
Location
Charlotte, NC
The current just equalizes the voltages betwenn the 2 points, and yes the same thing happens to birds, when they land on the line a small arc is drawn to raise the bird from 0V to line voltages, at lower voltages 4800V-around 30kV the current is small enough that it dosent bother the bird, at higher voltages the bird feels it, thats why you dont see birds on 120kV and above lines.
 

LarryFine

Master Electrician Electric Contractor Richmond VA
Location
Henrico County, VA
Occupation
Electrical Contractor
zog said:
. . . why doesn't a bird fry when they approach the single line conductor?
Anybody know the capacitance of a bird to the earth? ;) It's gotta be less than that of a helocopter.
 

mdshunk

Senior Member
Location
Right here.
LarryFine said:
Anybody know the capacitance of a bird to the earth? ;) It's gotta be less than that of a helocopter.
That reminds me of that video where the man says, "...don't forget to change the setting from bulldozer to eyeball."
 

ELA

Senior Member
Occupation
Electrical Test Engineer
LarryFine said:
Anybody know the capacitance of a bird to the earth? ;) It's gotta be less than that of a helocopter.

About 10 beak-o-farads!

So I think I get it now. It is a matter of the relative capacitance of the object in contact with the line. The larger the capacitor the larger the reactive current flow.

Thanks
 
Let me add this info as well i have one of my frend from other country he is helicopter polit and he used to work for POCO but atm not anymore [ personal reason i rather not say why here anyway.,,]

any helicopoters near powerline they are pretty hevey moddifed to use sorta what you guys heard the term " Farrely cage " [ hope that right spelling ] and have all the bonding wires allover the main helicopter that including both fuel tank and engines so the stray voltage don't wreck them.

and the other thing they hold the bird [ helicopter] at steady spot for pretty long time and #1 item is safety when work around the Power lines.

and the other issue is the noise from rotors and engines is pretty close to deafing level so they use both hand signals and head set intercom system.

Merci, Marc
 
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