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A balloon pilot asks about power line retrieval considerations.

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bobledoux

Member
I’m a balloon pilot. Our greatest safety concern is power lines. I’m looking for a way to determine the safe options in the following scenario:

Our friendly balloon pilot is becalmed over a rural power distribution station. He sits 100 feet above the power lines. He is almost out of fuel. Fuel exhaustion will result in the balloon settling into the power lines in the power station.

He has a drop line consisting of 150 feet of nylon that looks like automobile safety belt material. He flings this roll over the side. The end falls to the ground. About 30 feet above the ground it leans against one phase of a rural power line; assumed to be a 12 to 22 kilovolt three phase line.

I’m on the ground. I would like to know whether it is safe for me to pick up the end of the line and gently pull the balloon sideways.

Considerations:

I don’t know whether the drop line is dry our wet, or dirty or clean. The ground might be damp or dry. All these are considerations affecting the conductivity of the circuit between the power line and the ground. How can I be part of that circuit?

If you ask a power company representative about this issue their response is based on the standard consumer reply, not to touch anything in contact with power lines.

In my 30 years as a pilot I have encountered a situation like this. One brave soul picked up the line and pulled the balloon to safety. I’d like better information before volunteering to become cremation Charlie.
 

crutschow

Well-Known Member
Most Helpful Member
It would seem prudent to have a small motor and propeller installed so you can move the balloon, at least slightly, if you are becalmed.

But, to your question, the conductivity of the nylon rope would depend significantly on how damp it is. If you don't know that about the rope, then touching one that's in contact with a HV power line is definitely dicey. You do indeed need to be a brave soul to do it. Don't know that there's any easy way to determine if it's safe.
 
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Triode

Active Member
maybe keep some heavy rubber linemans gloves you can toss down to them as well?
 

Hero999

Banned
I don't see how rubber boots and gloves can offer much protection because there's nothing to stop tracking.

Anyway to answer the origional question 22kV is nothing, it wouldn't put me off touching the cord unless it's really wet. 100kV is a hell of a lot more dangerous, at this voltage I would be concerned about touching that nylon cord unless I knew it was really dry and non-conductive.
 

Triode

Active Member
I was kind of joking about the gloves thing, they're going to be running along to catch the cord, they probably cant also catch gloves and put them on anyway, heh.

It always amazes me that people can get shcoked through kite strings and stuff, so I don't really understand this enough to say what would happen. To my intuition, it seems like a kite string, even a wet one, would burn up before it could shock a person to death, but history and mythbusters prove it to be possible.
 

bobledoux

Member
Linemen have technology to deal with these situations not available to the public. Cheater sticks are used to contact active high tension wires. Double layer gloves are available, good to about 10 kvolts. These tools are given great respect. They have limited life, are carefully stored, and tested, to ensure their continued safety.

When high voltage makes contact with the ground I am told the voltage diminishes as the distance from the contact point increases. Because of this we are told to take small steps when moving away from a wire in contact with the ground. That makes the voltage potential less between each step. We are also told that if in a balloon basket in contact with a wire to jump clear to avoid making contact with ground and basket at the same time.

I wonder about using a voltmeter to determine the presence of high voltage by grounding one lead and slowly contacting towards the power source.
 

crutschow

Well-Known Member
Most Helpful Member
It always amazes me that people can get shcoked through kite strings and stuff, so I don't really understand this enough to say what would happen. To my intuition, it seems like a kite string, even a wet one, would burn up before it could shock a person to death, but history and mythbusters prove it to be possible.
Since it only takes a fraction of an AC amp going through a human body to stop the heart, a wet kite string is more than adequate to do that of it contacts a HV line.
 

bobledoux

Member
Remember the marine dock cleat? Its that device you figure-8 your line around to tie a boat to a dock. I've thought about making such a device, with handle, from nylon. It would be kept in a sealed container. When needed it could be used to capture a drop line with full knowledge it had certified insulating qualities.
 

MikeMl

Well-Known Member
Most Helpful Member
If you have balls, do it this way. After the ballonist drops the rope, walk up an step on it, effectively "grounding" it under foot. If there is a leakage current along the 100' rope, the voltage drop across the last 1" between ground where you are standing on it will not shock you. Now without removing it from under your shoe, touch it with the back of your hand about 4ft above where you are standing on it.

If there is any leakage current flowing down the rope, the last 4 ft creates a voltage divider with the 35 to 100 ft above you. The drop across the last 4ft will be only 4/100 times the 12KV, or 480V, which if applied to the back of the hand will cause you to involuntarily retract your hand. If no shock, keep your foot on it while pulling it down.
 
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Diver300

Well-Known Member
Most Helpful Member
Wear chain mail.

You only need chain mail gloves, about £70 a pair, and metal boots. You need all of them joined together with flexible cable.

Don't touch the belt with anything other than your gloved hands. If there is any current tracking down the belt, which there could be if it is damp, the current will flow through the chain mail gloves, flex and boots and not through you.

How the professionals do it.
 

Hayato

Member
Cool video.

I think the greatest problem of wearing a chain mail, when you have a ground path and there is a corona discharge, is that air around you will be ionized. You won't be electrocuted but you'll be fried.

The same thing with kite strings. You create a ionized path, so that, like crutschow said, you get electrocuted for a fraction of seconds, enough to stop your heart.

It is not safe at all to touch HV lines, when you are at ground, it doesn't matter if it is with nylon, rubber...
 

mneary

New Member
The guy in the balloon can safely pull the drop line up. He's not grounded.

Then he should toss again to clear the wires.
 

bobledoux

Member
If you have balls, do it this way. After the ballonist drops the rope, walk up an step on it, effectively "grounding" it under foot. If there is a leakage current along the 100' rope, the voltage drop across the last 1" between ground where you are standing on it will not shock you. Now without removing it from under your shoe, touch it with the back of your hand about 4ft above where you are standing on it.

If there is any leakage current flowing down the rope, the last 4 ft creates a voltage divider with the 35 to 100 ft above you. The drop across the last 4ft will be only 4/100 times the 12KV, or 480V, which if applied to the back of the hand will cause you to involuntarily retract your hand. If no shock, keep your foot on it while pulling it down.

You could treat the drop line as a slider resistor. Touch the line right next to your shoe. If there is no voltage slide your hand up. If you have no voltage at the height of your head it is safe to grab the line.
 

Triode

Active Member
If i understand this right, the person on the ground is a random bystander, any special training or equipment wont work as a solution because there will be no way to deliver that much training or equipment in time from a distance.
 

bobledoux

Member
If i understand this right, the person on the ground is a random bystander, any special training or equipment wont work as a solution because there will be no way to deliver that much training or equipment in time from a distance.
The people on the ground are chase crew members. These are trained persons who help prepare the balloon for flight, follow it while it is in the air, and help put it away after the flight. My crew members have been with me for 15+ years.

THE BOTTOM LINE:

There exist circumstances where waiting for the power company could result in serious injury or death. These instances are rare.

Balloon crew members have been taught about the dangers of high voltage electricity. But in circumstances where their friends are at risk they may take unreasonable risks in order to help their friends. I've been looking for techniques that might reduce these risks. The "voltage divider" idea is the best I've found so far.
 

Diver300

Well-Known Member
Most Helpful Member
With the "voltage divider" idea, making the bottom few feet conductive will further reduce the voltage on that part. Making sure that if there is any leakage current, it goes elsewhere and not through the person will keep him safe.

My chain mail suggestion is all about doing that.
 
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