[C320-list] Lightning

[Jack Brennan]

Here’s what BoatUS says. The article does a pretty good job of covering all of the bases:

https://www.boatus.com/seaworthy/magazine/2016/january/lightning-protection.asp



Sent from Mail for Windows 10

From: Charles Martin
Sent: Monday, December 14, 2020 5:03 PM
To: C320-List at catalina320.com
Subject: Re: [C320-list] Lightning

Tom:

I think it would be; however, I don't live in an area that sees unusually
high lightning (Chesapeake Bay), and I don't go out if it looks likely (if
I can help it).  So I have not spent the money myself to mount a charge
diffuser.  But I would if I felt I needed it.  My wife and I are
considering snowbird like travel to the keys and Bahamas, and if so I will
spend the money.  Meanwhile, I simply use a chain clipped to a stay and
dragging in the water if I get caught in a storm.

Best,
Chip Martin
S/V Bonaventure (Sail # 767)
(410) 231-0199
chiprmartin at gmail.com


On Mon, Dec 14, 2020 at 4:30 PM Tom Grass <tgrass462 at gmail.com> wrote:

> Thanks Chip - just to confirm - you ARE saying that such a device on the
> top of the mast MIGHT be beneficial?  Is this correct?
>
> Tom Grass
>
> On Mon, Dec 14, 2020 at 2:21 PM Charles Martin <chiprmartin at gmail.com>
> wrote:
>
> > In a past life, I studied EMP and related E/M phenomena.  The point of
> > dissipaters at the top of the mast is to reduce the build-up of static
> > charge and retard the formation of ion “streamers” which can link to and
> > complete the path for a lightning strike.  The local balance of charge
> > between surface and sky will determine where strikes will actually occur
> > (they can and do strike the surface of the water); however, you may
> > significantly reduce the likelihood of a strike to your boat by ensuring
> a
> > good, low impedance connection with minimum bend between mast and sea and
> > continuously dissipating any excess charge at the masthead.  You may have
> > noticed similar dissipaters on aircraft wings.
> >
> > Best,
> > Chip Martin
> > S/V Bonaventure, Sail # 767
> > (410) 231-0199
> > chiprmartin at gmail.com
> >
> >
> > On Mon, Dec 14, 2020 at 2:42 PM Jack Brennan <jackbrennan at bellsouth.net>
> > wrote:
> >
> > > The consensus I’ve read from lightning experts is that the dissipators
> > > probably don’t do any good, although there’s no definitive proof either
> > > way. A lightning bolt is just too powerful to be diffused by a small
> > metal
> > > brush on the top of the mast.
> > >
> > > But, frankly, their guess and your guess is as good as my guess. If it
> > > makes you feel better, it may be worth the price.
> > >
> > > Jack Brennan
> > > Sonas, 1998 Catalina 320
> > > Tierra Verde, Fl.
> > >
> > >
> > > Sent from Mail for Windows 10
> > >
> > > From: Tom Grass
> > > Sent: Monday, December 14, 2020 12:23 PM
> > > To: C320-List at catalina320.com
> > > Subject: Re: [C320-list] Lightning
> > >
> > > Thanks for all of the replies regarding lightning.  What are your
> > opinions
> > > regarding a lightning dissipator mounted to the top of the mast?
> > >
> > > Tom Grass
> > > Bucket List
> > >
> > > On Mon, Dec 14, 2020 at 10:20 AM John morrison <
> > sail-ability at sympatico.ca>
> > > wrote:
> > >
> > > > I read something awhile ago that Catalina made a deliberate decision
> > not
> > > > to electrically bond all of the metal components. It basically said
> > that
> > > > lightning in the order of a Brazilian V will do whatever it bloody
> well
> > > > pleased. Bonding is expensive producing no benefits. This came up
> > during
> > > my
> > > > recent survey whereas the surveyor stated that all metal components
> > > needed
> > > > to be bonded. I discussed the issue with him and he withdrew the
> > > > requirement. I have two heavy jumper cables which I attach to the
> > shrouds
> > > > and then dangle in the water. Evidently it doesn’t help but it gives
> me
> > > > peace of mind……..sort of.
> > > > JohnM
> > > > 1999#574
> > > > > On Dec 13, 2020, at 11:39 AM, Jack Brennan <
> > jackbrennan at bellsouth.net>
> > > > wrote:
> > > > >
> > > > > Hi Tom:
> > > > >
> > > > > My 1998 320 has a thick cable bolted to the mast support and
> > connected
> > > > to a keel bolt. In theory, the mast is the lightning rod and the
> > massive
> > > > keel is the ground stake. However …
> > > > >
> > > > > Lightning is kazillion volts and basically does what it wants to.
> It
> > > > might run straight down through the keel, or maybe it does a side
> flash
> > > to
> > > > other metal such as the oven. We are lucky to have Marelon through
> > hulls
> > > > because they won’t attract side flashes and melt, the way bronze
> could.
> > > > >
> > > > > I live in Florida, the lightning capital of the world, and I have
> had
> > > > two close brushes with lightning in 40 years of off and on sailing.
> > That
> > > > should tell you something about where it should be on your list of
> > > worries.
> > > > >
> > > > > In the first, I was in my 19-foot sailboat about three miles off
> Fort
> > > > Lauderdale, making a late return at night from the Keys. I pulled
> down
> > > the
> > > > sails and lit a cigarette (I smoked back then) while lightning bolts
> > > struck
> > > > all around me for about 30 minutes. I could see them hitting the
> water,
> > > but
> > > > none hit me. Scared the hell out of me.
> > > > >
> > > > > The second was about seven years ago. My wife and I were scrambling
> > in
> > > > as a summer thunderstorm arrived in Hillsboro Inlet from the
> > Everglades.
> > > I
> > > > was dropping the anchor in 30-knot gusts when a bolt struck about 40
> > > yards
> > > > from us in the harbor. It knocked out random electronics in my
> Bristol
> > > 30,
> > > > but I didn’t feel anything.
> > > > >
> > > > > So my rules are take down the sails, anchor if you are in
> restricted
> > > > waters, lock the wheel to protect the rudder, go below and stay away
> > from
> > > > metal. I also shut off the electricity and put all cellphones,
> > computers,
> > > > portable GPS’s, handheld radios, etc., in the oven.
> > > > >
> > > > > The reason for that is something called the Faraday Cage. Anything
> > > > enclosed in metal won’t be affected by lightning. It’s why the 747
> > > doesn’t
> > > > go down when it is struck by lightning. If it does get bad, you have
> > the
> > > > ability to call for help.
> > > > >
> > > > > Hope this helps.
> > > > >
> > > > > Jack Brennan
> > > > > Sonas, 1998 Catalina 320
> > > > > Tierra Verde, Fl.
> > > > > Dolphin Cruising Club of Tampa Bay
> > > > >
> > > > >
> > > > >
> > > > >
> > > > >
> > > > > Sent from Mail for Windows 10
> > > > >
> > > > > From: Tom Grass
> > > > > Sent: Sunday, December 13, 2020 10:12 AM
> > > > > To: C320-List at catalina320.com
> > > > > Cc: Tracy Grass
> > > > > Subject: [C320-list] Lightning
> > > > >
> > > > > Wondering about lightning protection on Catalina 320 boats?  I
> don't
> > > > > believe they come grounded (mast to keel) from the factory -
> > wondering
> > > > what
> > > > > the members of this forum have done in an attempt to minimize the
> > > impact
> > > > of
> > > > > a possible lightning strike?
> > > > >
> > > > > Also what is the collective opinion of installing a Forespar
> > > Performance
> > > > > Products Forespar Lightning Master™ - Static Dissipater
> > > > > on your mast?  We're planning on sailing down to the Chesapeake Bay
> > and
> > > > > perhaps to the Bahamas in 2021 - just preparing in advance.
> > > > >
> > > > > Thanks,
> > > > >
> > > > > Tom and Tracy Grass
> > > > > Bucket List
> > > > > 2008 Catalina 320 MK II
> > > > >
> > > >
> > > >
> > >
> > >
> >
>