Typhoon Lightning Protection

[Steven_Shore]

I have read through the posts on this forum on this subject and found them to be inconclusive.

Since at the moment I am in the process of installing a stainless steel compression post between the cabin headliner and the keel, this would be a good opportunity to address the lightning issue.

A buddy shared the following article, 'An Approach to A Modern Lightning Protection System' (https://www.iims.org.uk/approach-modern ... on-system/) This calls for a copper ground plate to be fastened externally on the hull bottom. This calls for some through hull wiring and I am intimidated by the notion of doing through hull work.

I have two questions:

1) Have any of the good members of this forum tried this or a similar approach with their Typhoons?

2) Since much of the article contemplates protection of onboard electronics and since my Ty is electronics-free, is such a project even necessary?

I occasionally keep carla, my Typhoon, in a well-protected slip, but she spends most of her summer on a mooring in Westcott Cove, CT.

Let the debate begin!

[John Stone]

I don’t have a Typhoon. But I have a few thoughts I’ll share since you asked.

The Far Reach is not grounded. I have mixed feelings on it. I have read everything I could find on the topic. I have sailed through terrifying electrical storms and watched lightning strike the water less than 50' away, and let me tell you it made a big impression on me. I have also had a boat hit by lightning. I'm neither convinced one way or the other nor am I convinced the experts really know how lightning works when it comes to boats.. If they did, insurance companies would require lightning protection.

Still, I thought about installing the long narrow strip per RC Collins Compass Marine website. I didn't do it because, in the end, I know too many experienced sailors that simply don't buy into the theory of it being safer to bring the super high voltage associated with lightening into one's boat. There are boats grounded that get hit with no damage, some damage, and a lot of damage. There are boats not grounded that get hit with no damage, some damage, and a lot of damage. I just don’t believe there is anyway to control where lightning is going to go when it hits your mast or rigging.

The best I can tell is that the evidence seems to suggest that if you ground your boat you have a slightly higher risk of being struck by lightening, but a lower risk of damage to associated electrical equipment. BoatUS says cats are twice as likely to get hit by lightning as monohulls. Boats in fresh water get hit more than boats in saltwater. You could call your insurance company and see if there is a break in your premium if your Ty is grounded.

Where you sail might inform your decision a bit. Florida and the US SE coast is the lightning capital of North America. Connecticut, not so much. In the end I think you have to do what makes you least anxious. My last big electrical storm was singlehanding back from the Virgin Islands. I put my electronics in the oven and sat on the cabin sole at the bottom of the companionway and let the windvane steer the boat while the lightning flashed and cracked at the same time. Scared the hell out of me but once again we made it through without a scratch.

Would I ever add lightning protection? Yes, if I was convinced the evidence supported I was absolutely safer with it than without it.

No one can tell you with certainty what is safest to do when it comes to lightning protection.

[MHBsailor]

Steve, I don't know if the Typhoon had an optional lightning protection system, but according to the Cape Dory 22/22D brochure, the Cape Dory 22D came standard with one (and mine has it) but the brochure is silent about whether it was an option on the 22 (I imagine that detail is in the owner's manual).

I had a friend whose limited production 24-foot racing sloop without a lightning protection system was hit by lightning at mooring in Newport, RI some time ago, and he reported that there was evidence the lightning came down the mast, blew three holes in the hull, and the boat promptly sank. He bought it at salvage and had it restored better than new.

The question in a small sailboat is if it is worth the extra weight and cost? I imagine both may become a smaller percentage as boat size is increased. Apparently Cape Dory thought the juice was worth the squeeze for the 22D and made it standard on that model. JD

[Jim Walsh]

I can only offer anecdotal evidence on this shocking subject. My Erickson 29 was the victim of an afternoon squall at the southern entrance to the Cape Cod Canal some thirty-plus years ago. It was one of those squalls that turned the sky green and was accompanied by strong winds and lots of lightning. I didn’t dare enter the Canal until it passed so I found a marked anchorage on the west side of the cut and dropped the hook to wait out the squall. So had several others....there was no sea room to ride it out.
At the height of the storm the lightning seemed to be cracking nearby continuously. One bolt seemed to hit just beside the boat and the thunder clap was simultaneous.
Within a half hour it was all over. The bolt must have come in through the prop shaft as it fried my instrument panel, my VHF radio, and my Micrologic LORAN. At least it didn’t hit the mast. It was a long and careful sail back to my slip in Niantic, about a hundred miles away.
During my four cruises to Bermuda I’ve been treated to some spectacular displays of lightning. Some in the distance, and some right beside me. I just reduce sail if it is associated with squalls and try not to come in contact with any metal. My mast is keel stepped so I stay away from it when below.
I have the factory installed system where all of the chainplates, through hulls, engine, fuel tank, mast step, and fuel fill cap are wired to the ground plate bolted to the lower bilge. This was compliant with ABYC at the time. Seems to have done its job over the last thirty-six years....fingers crossed.

[wikakaru]

John Stone's comments are right on the money.

Here are some additional things I would consider:

* The Typhoon's mast is pretty short. If you keep your boat where there are other more inviting (i.e. taller) targets, I'd be less inclined to do it.
* The DynaPlate on the bottom will add drag and slow you down. OK, not a lot, but it's something to think about.
* As John Stone said, proper lightning protection seems to increase the likelihood of being struck by lightning but reduce the likelihood of damage if you are struck. Since you have no electronics to protect from lightning, my preference with the Typhoon would be to go with the option that decreases the likelihood of being struck.

Our CD22 came with a factory-installed DynaPlate; our Typhoon doesn't have one. I'm happy both ways.

Smooth sailing,

Jim

[s2sailorlis]

my 1984 CD22 also has the dynaplate installed. the P.O. has painted over the plate and i sanded it down to expose the metal. the wiring to the plate though is somewhat suspect as the wire diameter i feel is too small. it's probably about 12 gauge maybe. see pix (not great as they are screen captures from video...

[John Stone]

my 1984 CD22 also has the dynaplate installed. the P.O. has painted over the plate and i sanded it down to expose the metal. the wiring to the plate though is somewhat suspect as the wire diameter i feel is too small. it's probably about 12 gauge maybe. see pix (not great as they are screen captures from video...

That’s what was on my boat originally. I don’t understand how that little bit of wiring is suppose to handle several 100 million volts, hundreds of thousands of amps, and temps to 50,000° F. And the wiring runs all through the boat so that kind of current is going to run down the back stay, through the chainplate, down a small copper wire next to the hull, and to a 1/4” or 5/16” bolt then safely transfer to the water?

Someone convince me this is a good idea. I’m not being sarcastic. I am seriously interested in finding a way to protect myself and my boat from lightning. But I need an explanation that’s more than just theory or quackery. Some real evidence. Seems like a steel or aluminum boat is the only way to have good protection. A faraday cage as it were...like an airplane or auto.

I read some info somewhere posted by RC Collins (AKA Maine Sail) that includes pictures of damaged boat purportedly caused by lightning. It was the best analysis I have seen. But it didn’t seal the deal for me. It wasn’t enough to overcome my skepticism. Not yet anyway....

[Pembquist]

You can read about lightning protection for structures and that seems to work as buildings and towers get hit all the time. The one useful thing I got out of mindless browsing on boats and lightning was the idea of having beefy jumper cables that you clipped to the shrouds and dangled overboard during T storms. I assume lighting is going to take the path of least resistance so a straight conducting path to the sea is the path the lightning will take. I don't think it is like a hose where the conductor only has so much capacity and the excess spills over, I think it is more like street signs pointing the way for some machine that can widen the streets if it wants. One thing out of the structure protection handbook was to avoid "loops" meaning if the conductor is inside the building don't have it go ten feet in a horizontal direction down two feet and then back ten feet. Apparently the lightning has a different sense of impedance than us and will happily vaporize set/fire to the two feet that are in the way of taking a straighter path instead of going 20 feet out of it's way. This kind of makes me wonder if with a deck stepped mast the lightning is going to bother with shrouds but instead just jump from the mast step straight down through the cabin, then that makes me wonder if a keel stepped mast is going to be more likely to blow out the bottom as why should the lightning bother turning if the ocean is just a couple inches away through some fiberglass? You can see the problem, lighting votive candles is probably a good way to go.

[John Stone]

You can read about lightning protection for structures and that seems to work as buildings and towers get hit all the time. The one useful thing I got out of mindless browsing on boats and lightning was the idea of having beefy jumper cables that you clipped to the shrouds and dangled overboard during T storms. I assume lighting is going to take the path of least resistance so a straight conducting path to the sea is the path the lightning will take. I don't think it is like a hose where the conductor only has so much capacity and the excess spills over, I think it is more like street signs pointing the way for some machine that can widen the streets if it wants. One thing out of the structure protection handbook was to avoid "loops" meaning if the conductor is inside the building don't have it go ten feet in a horizontal direction down two feet and then back ten feet. Apparently the lightning has a different sense of impedance than us and will happily vaporize set/fire to the two feet that are in the way of taking a straighter path instead of going 20 feet out of it's way. This kind of makes me wonder if with a deck stepped mast the lightning is going to bother with shrouds but instead just jump from the mast step straight down through the cabin, then that makes me wonder if a keel stepped mast is going to be more likely to blow out the bottom as why should the lightning bother turning if the ocean is just a couple inches away through some fiberglass? You can see the problem, lighting votive candles is probably a good way to go.

Well, from my layman’s view I don’t see boats and buildings as the same kinds of structures. We have a lightning rod and are on the water confined to a very small space. And sometimes we have to go outside in lightning storms. Side flashes and holes in the hull can be fatal.

My issue or concern is this. Lightning is the mechanism whereby an imbalance between negative charges in the atmosphere and positive charges on the earth balance themselves. When we put a ground plate on our hull and wire it to our lightning rod mast are we not helping create a path of least resistance for lightning to do its thing? In other words we seem to be “inviting” the lightning to hit our mast to seek a convenient path to ground. We are using our boat to communicate between the two opposite charges. This single issue seems to be THE major point of contention between not just sailors but between experts too.

I am sure there is a lot I don’t understand about it. But I have not seen a consensus among electrical professionals that makes me think there is a single way to best ensure our safety on fiberglass sailboats with aluminum masts. I have read a lot of theory about a force that proves itself to be very unpredictable.

Interestingly, but not surprisingly, the Pardey’s had a thoughtful and practical way of addressing lightning. They never invited it “into“ the boat. Look at photos of Taleisin. All the chainplates are external and extend a few inches below the waterline. The bobstay is connected to a bronze strip that runs down the cut-water maybe 6-8’ back all the way to the leading edge of the external lead keel and the two are connected with a bolt. Lightning stays outside the boat.

When I was a kid we did as suggested by Pimbquest above. When thunderstorms approached we clamped jumper cables to the shrouds and trailed the ends into the water. We lived in south FL. Makes sense now.

Anyway, it’s a lot to think about. I tend not to think about it till I start hearing the booming getting close then I thing about it plenty....

[mgphl52]

We could also replace our aluminum mast with Sitka Spruce and use dyneema for our standing rigging.
Probably rather expensive, but I bet it would look great!

BTW: I have some really tiny dyneema on KAYLA for the topping lift.

[fmueller]

On replacing aluminum masts with spruce etc ... except trees have been getting struck by lightening since the dawn of life on earth ... just saying.

from general reading: "The idea of the grounding system is to divert the lightning current through a predetermined path so that it does not make its own explosive path through fiberglass, teak, crew members, etc."

From the best reading I was able to do about lightening protection, the idea is not necessarily to save the boat per se, but more essentially, limit loss of life by "directing" or "inviting" "most" of the current on pathways that are not human bodies and secondly, less catastrophic to the physical integrity of the boat.

In a "sky to ground" strike, in fact the pathway of the strike is always established by an emergent ground spike in the last few hundred feet of the eventually completed sky to ground "circuit" just before the super heavy current flows in a completed strike circuit (this happens very quickly but has been photographed and studied in detail) ... a lightening protection system establishes the emerging ground spike along a pathway or pathways that will be less catastrophic to life and structures.

This is actually pretty well understood if not in theory, practice, and is the basis of all lightening protection systems on buildings. It's not that the wire will actually necessarily completely carry the eventual millions of amps, or even the after currents of several 10s of thousands of amps (lightening strikes are a series of "pulses"), far from it ... it's that the wire will direct the establishment of the strike pathway as "benignly" as possible. (In other words, you'll at least be alive, to witness the sinking of your boat !!!)

In an unprotected boat you already have the mast and the attendant physical fact that it is an attractor - but you do not have the attendant "suggested" safest pathways to ground of the protection system. Oddly even just the mast affords you a level of local protection (a circle the radius of the mast) from a direct strike to your body. It's a statistical fact that strikes to un-masted boats are more deadly to the occupants on a per strike basis than masted boat. A grounded pathway is more critical in a deck stepped boat where the explosion out of the bottom of the mast will be at deck level and will "find" ad hoc pathways, (including thru yourself - you being an attractive bag of salty water).

When we put Jerezana back together a few years ago I retained the protection system and upgraded the bonding wires to 8 gauge stranded and replaced the plate - just for for the heck of it. As I have been reading about this issue again (thanks for the thread) it seems to me it would be pretty easy to make a pretty robust connection from the mast step almost straight down to the lead blocks in the keel. Nothing like that is in my 27. But there is also quite a bit of the anecdotal literature that suggests that the charge is actually mostly trying to exit at or near the waterline, as if the surface of the ocean is a giant capacitor.

Also, this puts the tiller/wheel argument to bed - unless of course you've up-grade to a wooden wheel.

oh BTW - my 2 cents