[Rhodes22-list] lightning protection

Tue, 19 Nov 2002 10:21:28 -0500

Brad,

We have this discussion roughly once a year.  When all is said and done, its
clear that this is a poorly understood phenomenon.  People selling things
will scare the shit out of you with horror stories.  They provide "experts"
who you have never heard of before, propounding disproven theories as facts.

None of the theories relate directly to the construction of our boats.  Most
of the strikes occur on sailboats where there is a direct electrical path
from the top of the mast to the bottom of the keel, frying electrical
circuits as they go.  Our masts are, what, 3-4 feet from the water?  They
are mounted on non-conducting fiberglass, with wooden support, and a lot of
air between the bottom of the mast and the water.

Now the first thing you are told about lightning is to not touch the mast
anytime you are concerned about it.  But your approach would involve running
to find an excellent conductor, carrying it on the deck, attaching it to the
mast while the other end is still in your hand, and leading it overboard in
such it way that it does not foul.  Every time I find myself in a potential
lightning situation I reaffirm the fact that I would not even consider this
approach at a time I was concerned that lightning might strike at any
moment.

We know that some lightning starts in the sky and goes down to earth while
other lightning starts in the earth and goes to the sky.  Our boats are not
susceptible to the earth to sky lightning because there is no direct path
from the earth to our masts--unless we attach a conductor to the mast and
drape it over the side and into the water.

There is a school that suggests that these lightning protection devices
generate more strikes on the boats they are supposed to protect.

I don't know, but I do know that I have never heard of an R-22 being
structurally damaged by lightning.  And I always go back to my main motto:
"If it ain't broke, don't fix it."

Bill Effros

PS -- Sorry to hear about your headache.  Maybe it was the fumes from your
generator?

----- Original Message -----
From: "brad haslett" <flybrad@yahoo.com>
To: "The Rhodes 22 mail list" <rhodes22-list@rhodes22.org>
Sent: Tuesday, November 19, 2002 9:38 AM
Subject: Re: [Rhodes22-list] lightning protection

Bill, several sources I've read indicate that is a
mis-conception.  The statistical data for boats at
moorings don't indicate a higher mast being more
likely to be struck than a lower one. Brad.
--- Bill Effros <bill@effros.com> wrote:
> Sail or dock near a boat with a 30' mast.
>
> Bill Effros
>
>
> ----- Original Message -----
> From: "brad haslett" <flybrad@yahoo.com>
> To: <rhodes22-list@rhodes22.org>
> Sent: Tuesday, November 19, 2002 7:58 AM
> Subject: [Rhodes22-list] lightning protection
>
>
> This all got started while doing research on
> installing a mast antennae.  Several vendors lightly
> addressed surge protection from lightning strikes to
> the mast and I thought, "who cares about electronic
> euqipment? I want the boat to survive!"  Yesterday I
> spent eight plus hours on the net researching the
> issue and downloaded a 3" binders worth of material
> including the R-22 site info.  My conclusion is
> this;
> sailboats take more lightning strikes than one would
> think, freshwater boats without grounding don't fare
> well, and, protection is not that difficult.  While
> there are many different opinions and several "old
> wives tales" the general concensus among the experts
> is that having a protection system on board does not
> make one more likely to be struck.  All protection
> systems pretty much do the same thing, they provide
> a
> path from the mast to the water.  While at dock its
> a
> simple matter of attaching a #4 cable or flat
> conductor to a 1' square or bigger conductor in the
> water.  The straighter the path and the fewer the
> bends the better (lightning doesn't like to turn
> corners).  Under sail is a different story.  No one
> wants to sail with cables on the foredeck and plates
> dangling in the water.  Therefore, a portable and
> quickly attachable system is needed (battery cables
> get knocked off at the moment of strike).  The
> StrikeShield system is perfect but expensive.  I am
> presently researching a "homemade", ie, Home Depot
> approach that will do the same thing for far less
> money. Most boat manufacturers don't address the
> issue, probably for liability reasons.  Catalina
> issues a bulliten from the ABYC on the subject and
> basically tells you "you're on your own".  Over the
> past fifteen years I have been caught at least three
> times in thunderstorms in powerboats and once in a
> canoe.  Now that my boat has a 26ft tall lightning
> rod
> I'd like to better my chances.  Ideas?
>
> Brad Haslett
> "CoraShen"
>
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