IHADAV8.com - Turbo Buick Tech, and Nonsense
General => IHADAV8 Playground => Topic started by: Steve Wood on August 31 2017, 03:47:10 PM
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I remember that when we did long line work moving equipment from front to rear, that static electricity was a problem. I assume this was from hanging the line below the chopper with a big basket of equipment on the end while moving a mile or two down the line?
I am guessing it is not a problem in rescue operations because the line is not moving thru the line and the rescue basket touches the ground or water when it goes down?
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Choppers can and will take on their own charge. I'm guessing you really want something to touch the ground before it uses a moist human as a bridge. Then again, that rope my have some sort of dielectric properties.
If that's the case, hooking a basket with something the same charge of the chopper would probably be prudent.
Has anyone else seen the show where helos couple themselves to high up VERY high voltage lines then do work on them. That's guys really got some balls that clank.
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The static is produced from the rotors turning thru the dust particles in the air. Kind of a friction thing. In the air it's not a problem because there's no ground. I have yet to see a rope used in hoist Ops, normally it's a steel braided cable. 7/28 if you know what that is. That cable and whatever is hanging from it better touch the ground before a you decide to grab it without a glove or you become the conductor. I've seen it knock a fella off a 40 foot conex trying to hook a tandem sling. He was real cool with his shirt off wearing some sunglasses but no gloves. He looked even cooler lying on his back.
In my world of flying chinooks for the army, unless it was a tandem sling leg, our flight engineer would hook the load on the center hook without the help of a load team while we hovered over the load. If it was a long line, 200 foot sling, we would land beside the load. Hook the slings on the hook and then hover the load before picking it up.
Since the chinook has tires, static whips are installed on the rear landing gear and they hang below the tire. Therefore touching the ground before the tires to discharge the static. Every helicopter I've seen with tires has these static whips installed. Every chopper I've seen with fixed skids, does not have these static whips installed. However, they do have steel shoes installed the length of the skid tube.
In every hoist op I've been involved with, the jungle penetrater or whatever is attached to the cable, must touch the ground first before being handled by non-gloved hands.
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thanks!
I don't think I ever knew where the charge came from. I know we were taught never to touch the basket until it was sitting on the ground and always wore gloves. We were told we would not screw up but once.
I have not seen enuf on the tv coverage to see how the operation proceeded in full.