I wonder just what the statistics are on being struck by lightning at sea. I
would guess the chances are small, sure everyone "knows" a person/boat/story,
but what is the milage per strike ratio for cruising powerboats. I respect
lightning, and nature in general, but it seems like we sometimes look for any
reason to stay home, safe. In 25 years messin around on the water I have had
one vhf radio ruined by lightning (I liked that radio to) that's it, I guess
I've just been lucky. As a Journeyman lineman working maintenace in rural
areas in the tornado alley, I've seen some lightning, up close and personal.
Our mantra was "if you're not a path you don't have a problem". I've watched a
direct strike two poles away from the powerline pole I was changing an
insulator on, using a belt and hooks, I had the 2f copper line in my lap with
a gut (insulator) on it and a ground jumper to the neutral on both sides of
me. I never event felt a buzz, because I was not a path. Your electronics on a
boat are the same way, if you put them in the path they will get zapped, but
they don't need to be in the path at all to work, except maybe sonars with
bronze transducers.> From: rcrogers6@kennett.net> To:
scottebulger@comcast.net; passagemaking-under-power@lists.samurai.com> Date:
Thu, 22 Mar 2007 18:57:44 -0400> Subject: Re: [PUP] Lightning preparedness> >
Well, I thought that's what I said. Protect the crew - that's feasible by >
creating a cone of safety using the mast. There is general agreement that >
this has a high probability of success.> > Equipment protect for gear that is
connect to any electrical or bonding > system is futile. Depending upon the
nature of the strike and the consequent > EMP, it is unlikey anything will
survive. Rewiring the boat is a little > unusual, but depends upon doing a
real analysis. Example: My RG8U VHF cable > looked perfect and passed a
continuity test. However, a buddy at EG&G wanted > to take sections of the
cable and place them under an electron microscope. > The cable was in fact
damaged by heat.> > Therefore, Scott, your idea of having disconnected spares
is the best > civilians can do. Spare batteries, a GPS, and VHF any other
spares you need > for survival and that you can afford, should be stored
aboard. I think I saw > a Faraday cage instrument panel built by Palmer
Johnson for a Mason (PAE) > sailboat. It was a complex, screened, metal framed
structure and I can only > wonder if it worked. On another list, it was
pointed out that most > electronic engine have a "limp home" mode. Whether
that mode is available > after a lightning strike was not mentioned.> > One
point not previously mentioned is the physical damage that can occur. > For
example, I know several sailboat owner whose thru-hull depth transducers >
blew out of the boat. Two boats were manned and survived while the third was >
unattended in its slip and sank. It is likely that these were direct >
strikes.> > When Navy CICs were run by DG mini computers, every component
(that I could > see) was wrapped in tantalum foil. The mini itself was
residing in a > thick-walled metal safe that formed its outer casing. There
was a lifting > ring built into the top of the box. I don't know if the Navy
uses that > technique anymore and several novels have suggested that a
battlegroup could > go blind from nuclear EMP. I'd like to think that they can
survive lightning > strikes without damage.> > My personal experience was that
electronics not connected survived a near > strike while everything connected
was damaged. One thing I learned was not > to allow anything to be repaired
because there are incipient failures that > will emerge long after the initial
repair - I know this! Datamarine, for > one, would not do repairs on lightning
damage - they were right.> > Ron Rogers >
_______________________________________________> > Passagemaking Under Power
and PUP are trademarks of Water World Productions, formerly known as Trawler
World Productions.> > To be removed from the PUP list send an email with the>
subject "unsubscribe" (no quotes) to the link below:> >
mailto:passagemaking-under-power@lists.samurai.com> >
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Bob asked:  I wonder just what the statistics are on being struck by
lightning at sea. I
would guess the chances are small, sure everyone "knows" a
person/boat/story,
but what is the mileage per strike ratio for cruising powerboats.

Scott replies:  Found this statistic, in the context of overall lightning
strikes, FL is the highest in the nation, of those strikes, quoting now:

Florida averages more than ten deaths and thirty injuries from lightning per
year. Approximately fifty percent of the deaths and injuries occur to
individuals involved in recreational activities, and nearly forty percent of
those are water-related: boating, swimming, surfing, and others.

So about 25% of the deaths related to lightning in FL are water-related.

More reading for the interested:
http://www.cdc.gov/nasd/docs/d000001-d000100/d000007/d000007.html

Just like Piracy, something to consider, not keep you off the water.  This
is relevant for me, because I'm installing several thousand dollars in
electronics right now.  I've just decided to install them in a way I can
disconnect the power and peripheral leads quickly and easily.  This gear is
my backup navigation and communications computer, backup VHF radio,
Nauticomp Display, and FLIR camera.  A few purpose built cables, bulkhead
connectors and grommets and I'll have a way to physically isolate the whole
works in seconds.  I believe I can do this without adding significant
complexity and cost.

And by the way, If I was keeping the boat in the Pacific Northwest, I would
NOT be doing this.  The only reason I believe this is prudent is I will be
spending at least 1.5 years in the tropics where lightning is more
prevalent.  For the PNW it's a rare event to get lightning, and there are
service facilities everywhere (or within a days towing).

Thanks, scott bulger, Alanui, N40II, seattle wa

And, there are some areas that go through bad periods. For two Summers in a
row, Annapolis, MD went through an extraordinary number of lightning strikes
according to my insurance company at the time. They tried to console me by
saying that they had been experiencing their highest lightning damage claims
in years.

So statistical data for different regions is important. I wonder if
insurance companies would be willing to share their data - not.

Ron Rogers

----- Original Message -----
From: "Scott E. Bulger" scottebulger@comcast.net
|
| And by the way, If I was keeping the boat in the Pacific Northwest, I
would
| NOT be doing this.  The only reason I believe this is prudent is I will be
| spending at least 1.5 years in the tropics where lightning is more
| prevalent.  For the PNW it's a rare event to get lightning, and there are
| service facilities everywhere (or within a days towing).