I have a patient who was hit twice by lightning. Once in her
house - it hit a tree outside, part of the bolt bounced off, came
through her window and hit her in the back of the head while she
was sitting in a chair. No reason - other than you can't
effectively predict what is going to happen.
From what I've read there is so much energy flowing within a
lightning bolt that it's jumping along any path it can find. Even
if you offer a grounded path there can be enough excess flow that
will skip off the path and damage surrounding areas. Or if the
grounding wire is not straight some of the electricity won't be
able to follow the curve of the wire and will jump to other areas
(thus I'm not thinking stainless chain would offer the best
grounding path).
I don't have a good solution. I'm interested in learning more
from the discussion.
I know a guy who has a length of
stainless steel chain stored on deck and connected to the
shrouds on each side of the boat. He dumps the chain in the
water when he thinks it appropriate. His boat was hit by
lightning in the past, but not since he got the chains, so he
does not really know how good it works.
My big fear would be having the
lightning blow out through the transducers and or thru hulls,
which has been know to happen. Probably nothing will save the
electronics, except maybe a portable radio stored in the oven,
but the extra conductors might carry away enough energy to
prevent a boat-sinking hole in the hull. At least that is the
theory. There are a lot of sailboats that have been hit by
lightning which failed to sink. That nothing reliable in
terms of protection knowledge has come out of all of these
close calls only goes to show how much luck is involved.
Last week a soft ball player in
Nova Scotia was hit and survived. As she reached out to open
the door on a storage shed, the shed was struck by lightning.
The current went up her arm and out her foot, with only minor
burns to the surface of her skin, but her clothing was "blown
to bits". After a night's observation in hospital, she
reported still feeling weak from having all her muscles
contracted, but otherwise ok.
Steve Thomas
C&C27 MKIII
Port Stanley, ON
----- Original Message -----
Sent: Tuesday, July 26,
2016 12:16
Subject: Re: Stus-List
Grounding a mast - 30mki
Thanks to Joe and everyone else who replied.
After reading a few articles like this one -
http://www.practical-sailor.com/blog/-11222-1.html,
it sounds like there is little consensus on lightning
protection for sailboats. I'd be curious to know what sort of
lightning protection, if any, comes standard on new boats from
the well-regarded manufacturers of heavy displacement cruisers
like Hallberg Rassy etc. I just searched the manual for a new
HR boat and there's no mention of lightning or lightning
protection at all.
Someone raised the point on one forum that inviting this
massive amount of energy into your boat is a bad idea (IE a
cable going from the mast to a keel bolt). Not sure whether
this is a well-founded concern or not, but I'm leaning
towards Joe's idea of clipping some jumpstart cables to the
shrouds and hanging them overboard next time I'm caught out
in a storm.
_______________________________________________
This list is supported by the generous donations of our members. If you like what we do, please help us pay for our costs by donating. All Contributions are greatly appreciated!
