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So on the launch tower there is a round spire or exhaust stack sticking up. And then there are wires running from that structure to (apparently) the ground. But the wires don't seem to be in a lot of tension.

Are those wires grounding for lightning protection? Or maybe are they under more tension than they look like, and they are guy wires?

Edited by mikegarrison
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10 minutes ago, mikegarrison said:

So on the launch tower there is a round spire or exhaust stack sticking up. And then there are wires running from that structure to (apparently) the ground. But the wires don't seem to be in a lot of tension.

Are those wires grounding for lightning protection? Or maybe are they under more tension than they look like, and they are guy wires?

If they are what I think they are, they may the the wires to bail out from the launch tower in case of emergency, literally sliding down attached to the wires while still inside the IVA suit. It's not as fun as the Ares I ground escape system though, that one had a full rollercoaster for that purpose 

rollercoaster_zoom.jpg

Edited by Beccab
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14 minutes ago, mikegarrison said:

Are those wires grounding for lightning protection? Or maybe are they under more tension than they look like, and they are guy wires?

 

Oh, wait, you mean the single wire on the upper left of that image?

demo-1_falcon9_vertical_022819.jpg

Presumably lightning protection.

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1 hour ago, mikegarrison said:

So on the launch tower there is a round spire or exhaust stack sticking up. And then there are wires running from that structure to (apparently) the ground. But the wires don't seem to be in a lot of tension.

Are those wires grounding for lightning protection? Or maybe are they under more tension than they look like, and they are guy wires?

Pretty sure the spike is an lighting rod, its not exhaust. its wires to the spike for extra lightning protection. The wires at the rear of the arm is to escape the tower fast using them as zip lines. Apollo had an similar system. 
I assume its for situations who is less serious than using the capsule abort system to get away, also nice to evacuate ground crew is needed. Note that Falcon 9 if fueled after the astronauts is strapped in and I assume they would stay in until it was drained again if it was an hold. 

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I thought I was quite clear about what wires I was talking about. I guess not? I was talking about the wires that go to the ground in all directions from the very top of that tubular structure that sticks out from the top of the tower. They are clearly not "ziplines".

My assumption is that they are current paths for lightning protection, but I was wondering if anybody here knew that for sure.

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41 minutes ago, mikegarrison said:

I thought I was quite clear about what wires I was talking about. I guess not? I was talking about the wires that go to the ground in all directions from the very top of that tubular structure that sticks out from the top of the tower. They are clearly not "ziplines".

Your image (the better one of the whole tower) was on the previous page. That new image I posted was on this page, and the only multiple wires in my sunset (sunrise?) image were the ziplines, hence the confusion I think. Everyone simply looked at the pic 3 posts above your question post vs previous page.

41 minutes ago, mikegarrison said:

My assumption is that they are current paths for lightning protection, but I was wondering if anybody here knew that for sure.

1009197main_0739-1.jpg

That's the same way Shuttle did it, and the same tower, so "yes."

fSraj.jpg

Mast is a fiberglass insulator to hold up the wires to conduct the strike away from the pad/vehicle.

Edited by tater
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I see, thanks.

So a catenary wire is a wire that follows a catenary curve, which is to say the natural curve that an untensioned suspended wire follows between any two points. This seems like confirmation for what it visually looked like to me about those not being tensioned guy wires. They probably act as both current paths and maybe even sort of a widely spaced Faraday cage? Thus the "cone of protection"?

(I am not an electrical engineer.)

Edited by mikegarrison
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46 minutes ago, tater said:

Your image (the better one of the whole tower) was on the previous page. That new image I posted was on this page, and the only multiple wires in my sunset (sunrise?) image were the ziplines, hence the confusion I think. Everyone simply looked at the pic 3 posts above your question post vs previous page.

1009197main_0739-1.jpg

That's the same way Shuttle did it, and the same tower, so "yes."

fSraj.jpg

Mast is a fiberglass insulator to hold up the wires to conduct the strike away from the pad/vehicle.

Interesting,  but it makes sense you don't want lighting down the launch tower because of edge currents. 
High power transmission lines has lighting protection lines above the power lines, they are grounded at each tower. 
An teacher of mine was on the line inspection crews for the line, they found 20 something dead sheep  at the base of one. They assumed poison, plenty of stuff like antifreeze solution is something animals love to eat but is very dangerous to animals. 
Same with dangerous salts. 
But it was edge current from the lightning who killed them.
Hoofed animals has an critical weakness to electricity. plenty of cases there earthing faults killed horses but their handles did not notice anything as they had rubber boots rather than iron shoes. 
Or then I helped my father change an outdoor light, I said we has an  earthing faults here, he said it was fine, I was barefoot in wet grass, he had rubber boots. 
 

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