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Old 07-05-2004
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Lightening strike

Now this is a funny thread.....I think that I will sacrific a stuffed animal or two since I would not harm an otherwise living creature.

Seriously, there is not much you can do to prevent the agony of fried instruments. When lightning strikes a boat there is enormous induced current and that completely overwelms any defenses that can be applied. The damage has been amazing to me. Many of the inline fuses got so hot that not only did the metal in the fuse melt down, but the glass melted as well. Pieces of the bilge pump switch (which was turned off at the time) was blown across the cabin. One of the two batteries were fried as was the three way switch which was turned also off. Light bulbs on the mast were actually welded into the light fixtures.

The boat itself sustained not visible damage. She was out of the water for a bottom job at the time. She has a keel stepped mast that sits on an aluminum beam that is bolted to one of the 25mm keel bolts. I have conjectured that the lightning simply was conducted straight through the mast and out through the keel but there is no way to know. Typical of southern hemishere boats,none of the thru hulls are bonded and so they sustained no damage. (I have heard of thru-hulls blasting out chunks of hull in a lighting strike sinking a boat rather quickly).

The current data, albeit somewhat anecdotal suggests that the Ion Diffusion brushes actually seem to attract lightning so I don''t know of a way to protect my boat from a strike.

As of last night all of the systems are back in and seem to be working, albeit in need of calibration, so I am heading out cruising in a few minutes.

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