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Does anyone have any experience with powerlines or is aware of the dangers involvolved in jumping them.....
i have jumped one and felt a tickling sensation, some of my friends told me they saw blue flames on their feet.....
i just found two more powerlines and really want to jump them, but as i said have no idea about the dangers
thanks gee

I've jumped them quite a bit.

The "tickling" and "blue flames" are probably static electric discharge between you (most likely your feet) and the tower when you exit. I've seen it quite a bit. In my experience it's most likely to happen in a dry, windy season, but I don't know why (since I've only had it happen on power towers I assume the power lines are the root cause, not the wind).

I have experienced some muscle cramping from the shocks, but always in my legs and feet, and never anything really serious (i.e. it always worked itself out before I got to the ground). I do know people who worry enough about it that they always go hand held, in case they have some kind of cramping in their upper body that might make it hard to pitch. This has never, to my knowledge, actually been a problem, though.

I think the real major consideration is the power lines themselves, and they are usually very well insulated and kept away from anyplace you can reach from the structure. I have jumped a couple that were not so nice that way, but even with jumpers heads within a couple feet of the power lines at the exit point, we had no real problems. I'd imagine that depends on the strength of the current in the lines, though, so if they are very powerful, you'd want to stay further away.

Hope that helps.

Thanks Tom......i just heard that you should stay away as far from the cables as the isolators (the things that keep the cable away from the tower) and on the ones i have found that will be quite hard......someone said something ybout a flash if you are to close (i am not sure of the correct english word)
well ill let you know how it was (if i get the chance [:P)
so is there a chance, that you get hit by a flash, when you pass the cable on the freefall without touching anything??

Do you mean the towers that support the power lines? If so, I've jumped 3 different ones. In one case, the exit point was live and once you approached (directly above a live wire), you start to feel a tingling force field feeling. On the other two, the sides jumped were dead and there was no feeling at all.

One of the guys I jump with said he talked to a power technician, who recalled a rule which basically said don't get within 7 feet or so of a live wire. I, nor the others I jump with, have ever felt any ill effects directly following a power tower jump, most of which have been over the live wire.

However, the rule for towers should still apply: get on, get up, and get off as fast as possible.

i am not worried about the tower itself....its the cable that you fall past ...and on the ones i found you have to jump off above the cable and pass it on the way down

That's what I meant We exit about 6in above the middle wire (3 in all) and fall past the others. I've never seen or heard of any incidents from the lines themselves. The only sparks/etc I've seen has been after leaving the tower itself, never arcing to the lines.

Thanks guys
looks like i am off to have some fun now.....thanks for the quick replies

I think the english word you are looking for is "arc", but we'll have to check in with some English jumpers to find out for sure. (Hey, English dudes, if you read this, can you help us out? )

I am uncertain as to how close you can get to the cables, relative to the insulators. I do know that there is a safety margin built into the insulators, and that you'd have to be quite close to the line for it to arc to you without you being grounded. I believe there would have to be a whole lot of current for the electricity to arc to an ungrounded jumper as he fell past.

I think the closest I've been (when ungrounded) to a high voltage line was probably about 6 feet. The closest I've been when grounded (which ought to be more dangerous) is a bit closer.

Hey Tom.....
thanks, thats the word i was looking for and its definitely the thing i am scared off.....but looks like a lot of guys have jumped them and i havent heard of any major problems......so i guess its just another object to add to my local spots

Watch out for that big Sycamore tree at the bottom of that powertower Mr. Tornolf it's a killer.

Break a leg man!

I cannot think of a reason to ever jump that shit covered tower ever again, especially after someone already beat me to the punch on the leg

But there are so many other bones to break jumping that tower. The buzzards have all flown south for the winter anyway.

C-YA

Sounds like a reasonable rule.

If you ever find yourself in a position to serve as a path to ground from several hundred thousand volts, you will no longer be able to find yourself. That's the danger of the voltage levels we're talking about. And these huge voltages (for all practical purposes in this case) don't change.

So that's that. Don't provide a path to ground. Most people get that.

Now, there is another issue. The current flowing through the wire creates a field around the wire that can induce voltages in other objects nearby (like you). This has nothing to do with the line voltage (in fact, if the transmission-line voltage is higher, then they can transmit the same power with less current).

The magnitude of this effect depends how big the current is. And the current varies depending on the load. So, if it's summer early evening and everybody is running their ac and all the arenas are lit up and a bunch of companies are still running 2nd shift and an alternate transmission line is down for some maintenance and the neighboring state's reservoir is low so they're borrowing a bunch of extra power...
...then the voltages induced in you are going to be bigger than a comfortable spring holiday morning.
The magnitude of the field also varies (for a wire) roughly with the square of your distance from it. So when you're really close to it, the field differences across your body will much bigger than if you're a little further away from it.

Thing to remember: the induced voltages across your body do not require any conductive path between you and the wire, or between you and the ground.

ie:
...and stay as far away from the transmission lines themselves as you can.

I found that when I started to get out there by and then between the Armatures. Usually It's the middle one because It is the longer one than the one above and one below.
The static is worse but I try to keep a constant hand hold on the metal structure as much as possible as I am making my way out there to make a launch so the static does not get to build up as bad.
It's when you are standing there with your boots as the only thing touch and the static builds up. Then you gab something and get popped by a spark.
When you are surrounded with wires above and wires below and you are on the middle arm standing. It's like jalisco says you are surrounded by a huge amount of energy. like a huge energy flux field. it' gets to feel pretty weird. Your senses tell you that you are not suppose to be there
The static builds fast on the armatures and I might be wrong but I think I got zapped even more on dry and cold nights when the air is real dry/low humidity.
.

Hello Gert, (Tom, Ray)
Nobody has made the list off one yet.
Altitude is altitude friend.
Avery

Relevant link, specifically post #16, but can't figure out how to link direct?

http://www.dropzone.com/...d%20static; - 389716

The only ways you could get killed by a powerline is of course to hit one or to be in a flashover. Arcs are usually cause because of faults in the powerline system.Towers that have been hit by lightning have faults that glow in the dark and it is something that you would be able to see when you are about to climb the tower(if it is night). This happens when the power jumps from the wire across the insulator to the ungrounded tower(you would have to have the worst luck in the world or be DUMB enough to climb a giant metal object in a lightning storm) this causes a shortcircut. . A shortcirtut happens when you touch two or more line together or connect them with something like your body (wearing a baserig) and complete the connection(bridge the gap) or ground the system out. Substations have circutbreakers and can detect shorts and cut the power for a split second to stop the arc(flashover). This is usually cleared up and life goes on and the line is as good as before and ready for you to climb the tower again:)

As far as the Arc that you see when you jump a tower. When you are on a tower the air around you gets ionized and you break that connection when you jump, if you were grounded at the time then you could create a fault in the system and have a flashover to the ground and you would be a crispy critter. You are not grounded at the time, so it is impossible for you to get electrocuted.

As far as that feeling that you feel when you get off the tower or are on the tower it could be that you are in an electromagnetic field. Power-frequency fields in the US vary 60 times per second (60 Hz), and have a wavelength of 5,000 km. Power in most of the rest of the world is at 50 Hz. Broadcast AM radio has a frequency of around 10^6 (1,000,000) Hz and a wavelength of around 300 m. Most microwave ovens have a frequency of 2.54 x 10^9 Hz, and a wavelength of about 12 cm. X-rays have frequencies above 10^15 Hz, and wavelengths of less than 100 nanometers.

Power-frequency sources are clearly too short compared to their wavelength (5,000 km) to be effective radiation sources, but can still leave your electrically ran system we call your body a little off.

The insulators are always sized for the voltage that is on the line....(larger and longer the insulator, the more voltage is there). So to maintain a safe distance, at least stay the length of the insulator away from the wire......good luck!

This kind of suit should address many issues

http://unitech-rf.com/personnel-rf.html

http://www.nspworldwide.com/rf_frame.htm

It forms a Faraday cage around the body, so electric fields and magnetic fields inside are nil.

True. So, it's not electromagnetic radiation we need to be concerned about. It's induced voltages (and thus currents) that we should pay attention to. When you get really close to a wire transmitting a high ac current, the field around that wire induces currents in objects near it, including you. This is different from radiation effects. Think transformer.

For example, the current density induced in your body 1/2 meter from a single 60Hz transmission line carrying 1000A would be on the order of 1 mA. Let-go current (at which point ventricular fibrillation may occur) is 9mA for men, 6mA for women.

I've made a few off a local powerline set here and found it to be a bit trippy watching someone go slow off the middle wire platform as it often arced to them as the passed five or so feet under the top wire and in the fog the insulators tended to have a little light show of their own but jumping the top platform with a slight under hang on exit but over hung overall was always a great way to gain 300' of adrenaline.
Enjoy dude, Nathan

Insulators' are bell shaped to cram more overall insulating distance in a shorter space, take the center point of the ceramic dish and go to the outside edge and back to the center for insulated distance. Stack 5 to 15 of these "bells'" together and the insulated distance gets' significantly longer. They do this with some saftey factor for dirt, moisture and the like. Respect the power these things have, they will blow cooked steaks' out of you if not just leave a cinder. Have fun PT's are a thrill!

Really, really high voltage wires will arc into ungrounded stuff near them, but it has to be a huge amount of power.