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People, Boats, and Stories => Sailing stories => Topic started by: CapnK on May 15, 2009, 03:56:27 PM

Title: When lightning strikes...
Post by: CapnK on May 15, 2009, 03:56:27 PM
I mentioned the other day that I'd be re-rigging a Triton this weekend. It came about because the owner had noticed that the starboard shroud had parted, one strand unwinding, between the spreader and the upper tang. I told him at the time that I thought that was an extremely odd place for the wire to break.

Today, after dropping the stick, first thing I wanted to see was just why/how a shroud could part in that place. Imagine my surprise on finding this:
Title: Re: When lightning strikes...
Post by: CapnK on May 15, 2009, 03:59:50 PM
Hmmm...

That made me look at other parts of the rig more suspiciously. The backstay had some evidence of a strike also, a strip of melted stainless about 4" long. The masthead fitting was affected - you can see that the pin holding the backstay in could have pulled right out, as the crane was actually cut thru on port side. And the dammit ring holding the backstay pin in had dribbled down onto the topping lift block. *This* is why you *always* put your pins in with the wide end up. :)
Title: Re: When lightning strikes...
Post by: CapnK on May 15, 2009, 04:02:30 PM
The VHF antenna took a good hit also, as evidenced by the charred and fused material at it's bottom.

And before seeing any of this, I had wondered at the odd cratering which is randomly spaced around the hull. I think the strike may have actually blown these chunks of gelcoat of, but am not positive of that. Will probably have a better idea of this after we do some hull prep next week.
Title: Re: When lightning strikes...
Post by: CapnK on May 15, 2009, 04:03:58 PM
Last, and unrelated, this boat just came into the marina. I like the "smily face stern", even though it is not really a sailFar boat. ;D
Title: Re: When lightning strikes...
Post by: AdriftAtSea on May 15, 2009, 04:27:49 PM
The smiley face stern is nice.... the lightning strike not so much....
Title: Re: When lightning strikes...
Post by: dnice on May 15, 2009, 04:35:21 PM
Just out of curiosity, does that triton have a grounding plate and/or any other form of "lightning protection"? (like an ion brush or grounding to the thru-hulls or whatever else people do)
Title: Re: When lightning strikes...
Post by: CapnK on May 15, 2009, 04:52:48 PM
If the Tritons were constructed in the same manner as the Ariels (likely, given that they were produced by the same company in the same factory ;) ), then the chainplates were bonded (sorta) to thru-hulls, and perhaps the engine.

On my Ariel, there was a wire of large size between all those metal parts. That said, the wire followed a tortuous and convoluted path, so my guess at its effectiveness in routing the voltage of a strike to ground would be that it was neglible. :)

There was no sort of lightning gizmo on the spar.

Near as I can tell when this would have happened, the boat would have been in her slip, connected to shorepower, in brackish/mostly saltwater. The damage to the shroud and backstay would have been 20-25' off the water. I have not seen any indication of lightning damage at deck level.
Title: Re: When lightning strikes...
Post by: TomRay on June 09, 2009, 07:35:30 AM
I think that the fact the lightning attacked the dammit ring shows that God doesn't like them either.