Sailing in thunder storms.

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Having seen effects of a lightning strike on a ship in West Africa - I reckon you could do all you want - but still you are going to fry so much. To the poster in USA who puts a jumper lead from stays to water ... sorry but you'd need a cable as big as your boat to carry that load if you got struck. The lead you have even if welders cable would only light up like a bulb filament. Disconnected equipment would still be frazzled if boat hit by the electromagnetic and sheer power of the strike.

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The point about having a lead into the water is to prevent a lightning strike. If you've got a connection from your rigging to the water, then the mast etc. acts as a lightning conductor, giving a "cone of protection" extending at about 45 degrees downwards from the top of the mast. I have heard (no experience, I am glad to say) that the worst damage from a lightning strike happens where the charge "jumps" from the chain-plates down to the water. Lighning conductors don't work by providing an easy path for a strike, they [provide a path by which the charge can "leak" away so it never builds up to a level where a strike happens. Yes, you can get quite high currents, but most lightning conductors are not that heavy.

Sailing boats whose rigging is earthed ought to be pretty much immune to lightning strikes, just as church towers and high buildings are on land. Our church tower is definitely the highest point for miles around, and because it is protected by a well-earthed lightning conductor it certainly hasn't been hit by lightning for as long as I can remember - and that's 30 years.
 
I agree with everything that you say. I was terrified by a massive thunderstorm in the middle of the north sea that followed a cold front whipping through winds were topping 45knts for over 2 hours and lightning was striking all around us, the worse thing was someone had told me in a bar somewhere that if you suffered a strike, the lightning would travel down the mast and melt the keel bolts and the keel would fall off! seems laughable now but at the time i thought we would almost certainly be struck and suffer these dire consequences. Afterwards i resolved to find out all I could about it before it happened again and form a plan, which is much as you suggest.
 
met a thunderstorm in the gulf stream just off Cape Hatteras that was just like being in a disco the flashes were so frequent. Only a few forked lightning bolts seemed to strike the sea but they were all round us. It was probably the most terrifying/ magical/ awesome sight I've seen on a yacht. The skipper had a thick bit of battery cable attached to the shrouds and over the side (and all the elecy gizmos in the oven) and we weren't hit so.... luck, good prep, who knows. Thunderstorms still get my imagination going about the consequences of getting hit but having sailed through a good one I'm now a little less terrified about the chances.
 
did you get caught by it Allan?Was out off Barry when it went through.Torrential rain lots of forks hitting the water.I was touching the metal steering wheel as little as possible /forums/images/graemlins/grin.gif

Visibility down to zero in the rain Saw a small yachtjust before the vis closed in ,didnt envy them at all.At least this storm didnt bring the violent wind that i have experienced before with lightening storms.

I hope noone was struck.
 
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