Lightning protection

ORCA

New member
Hi

Does anybody out there has any advice what to do about lightning protection on a C-Dory 22 :?

Any advice....

Regards Chris
 
Funny, Roger!

I hide out in small coves on the lake with tall ridges and trees all around!

We once sailed in a national championship on Granby Lake in Colorado where they said "If you don't like the weather, wait 15 minutes, and it'll change."

Maybe the 8000 ft elevation had something to do with it !?!

A storm rolled in and in about 10 minutes there was so much electricity in the air we couldn't touch the wire shrouds or mast without feeling the sizzle and tickling, so we raced over to shore, laid the boat on it's side, and crawled up under some trees (not smart either, but better than out on the lake!).

Bob Austin should be able to give some real advice on this topic with his sailing and powerboat experience in the ocean and also because of his living in Florida, the Lightning Capital of the U.S!

In the meantime, here are some things I remember that are mostly conmmon sense:

On sailboats, the mast is grounded from the base of the mast and/or shrouds to a ground plate on the bottom of the hull or to the keel. The negative ground of the 12v system is included in this. The idea is to get the electricity to pass from the mast to the ground around the people rather than through them (!)

It's almost impossible to protect the electronics fully, as the voltage and current are so high that fuses and circuit breakers are arced through easily.
To help save the electronics, perhaps one could detach their wire connections, then stow them in a metal box, if time permits. Handheld back-ups would be important in most instances after a strike.

A power boat could be similarly protected by running a ground wire from the highest metal point on the roof to a suitable ground, like the leg of an outboard.

One should also know that a direct lightening strike on an outboard could disable all the electronics, which can include the ignition, fuel injection, and alternator functions.

Radio antennas are another, higher strike target that should be lowered during lightening storms, time permiting.

Some will say that making the boat or mast grounded will actually encourage lightening strikes, but at least those inside will be better protected.

People inside should move away from all metal objects and get down low away from metal window frames, etc.

I'd drop anchor if possible, so that I wouldn't have to be up or in contact with the helm, unless, of course, I was in a posiion to make a safer harbor or better position.

Last of all, set down on a safe place like the Porta Potti, pour yourself a large glass of wine, :cocktail and enjoy yourself! You've done what you can, now it's up to Mother Nature's Random Roulette Wheel in the Sky!

Joe.
 
There happens to be an article on that exact topic in Power Cruising magazine this month. Unfortunately, I think the solution costs more than our boats.

I don't remember everything in the article, but some things did stick in my head. One of the issues I remember is the controversy over whether or not it makes sense to have a lightning rod on a boat. Some insist it makes the boat a bigger target.

The message I took from the article is basically what Roger stated above. Avoid it.

-Sarge
 
Short story. I was anchored in my 31 ft trimaran with a 40 ft ungrounded mast along with 4 other similar trimarans in our group in the Bahamas. We were within 50 ft of a large twin masted schooner with masts heavily grounded to a copper strip beneath the waterline. Tropical depression came through, lightening hit the twin masted sailboat at about 5am, we watched the explosion and sparks like the 4th of July from the electronics and weather equipment when it got pulverized at the top of the mast that got hit.

Post briefing among the tri's: We won't be grounding our mast, and, we will look to anchor near someone who has. True story.

So, SeaDNA Roger's suggestion is possibly spot on!
 
I have come in with the wheel so electrically charged I had to bump it with the backs of my hands to change course, electricity going out the antenna so strong you could hear it, and the engine not running much above 1/4 speed because the thunderstorm was sapping its electrical energy. I was glad to leave the antenna up, and let it take whatever might come, since lowering it would mean I was the highest thing in the boat (Whaler Montauk). The occasion: clear, calm day, bright sunlit sea floor, I was in 17 feet of water sifting for Megalodon sharks teeth, had been down for about 3 hours when I noticed the bottom suddenly got dark, came up and there was a thunderhead right on top of me. Headed back to the inlet (about a mile and a half) with lightning popping all around. Whalers are grounded.
 
We have been in a number of lightning storms in various boats. In the C Dory we would disconnect the electronics--antennas, grounds, transducers and posative and negitive power cables. Remember than lightning can come thru the water in a near by strike.

Anchor if at all possiable. Put antennas down. Stay away from any metal in the boat. A ground plate, lightning diffuser etc would do little if any good in a C Dory or TC.

We have had direct strikes on a boat with wooden masts and shrouds which were directly grounded to the water with chains--and the only damage (all electronics disconnected)--was to diodes in wind instruments.

On another boat, with aluminum mast, fuzzy disspiator, direct copper tubing to a 1 sq foot plate of copper---after we sold the boat--had at least three major strikes with damage to rig, all electrical and electronics....so I am not convinced that the "direct path" really offers much protection--at least to a rig and the electrical/electronics....

There are anumber of good web articles on lightning--espicially those by University of Florida.
 
Dora~Jean":p4nly30i said:
Short story. I was anchored in my 31 ft trimaran with a 40 ft ungrounded mast along with 4 other similar trimarans in our group in the Bahamas. We were within 50 ft of a large twin masted schooner with masts heavily grounded to a copper strip beneath the waterline. Tropical depression came through, lightening hit the twin masted sailboat at about 5am, we watched the explosion and sparks like the 4th of July from the electronics and weather equipment when it got pulverized at the top of the mast that got hit.

Post briefing among the tri's: We won't be grounding our mast, and, we will look to anchor near someone who has. True story.

So, SeaDNA Roger's suggestion is possibly spot on!

I use the same strategy when hiking above the tree line. I hike with a tall bald guy and I tell him the conductive jelly is sunscreen. :wink:
 
One old-timey (i.e. low-cost) trick here for boats without fancy lightning protection, is to carry a pair of jumper cables. If need be, clip one end to the mast (or other high point) and drop the other end overboard.
As to protection or not, consider houses in high-lightning area. Do you want a strike to hit the lightning rod or explode the end of roof and set it afire?
 
barefoot-

I've heard that advice before, and it sounds good to me.

Plus, you've got some jumper cables which can be used to jump another boat (would have to be longish, though).

Also, you can jump your own batteries from one to the other if the ones for one engine go dead and you don't have the type of system built in to combine or emergency start one engine's batteries with the other.

AND UPON FURTHER THOUGHT, I think Roger could take further advantage of the possibilities of this system by equiping his hiking buddy with a shiny aluminum hard hat with a couple of jumper cables trailing behind.

Joe.
 
Chris, I think your concern is valid. Some places you visit as you go farther north the boat may well be the tallest thing around. Seems the best advice is to practice completely disconnecting all electronics, then practicie it again, and to keep a couple of emergency spares (radio, gps) in a metal box and hope for the best. (Now if you jump in the jet boat and anchor next to the dory you would be lower).

Good luck,

Mark
 
barefoot":3sgsuoys said:
One old-timey (i.e. low-cost) trick here for boats without fancy lightning protection, is to carry a pair of jumper cables. If need be, clip one end to the mast (or other high point) and drop the other end overboard.
As to protection or not, consider houses in high-lightning area. Do you want a strike to hit the lightning rod or explode the end of roof and set it afire?
The theory behind lightning rods is that an ionized area (field) is created above the grounded rod itself. A sharp point creates the strongest field, but a rounded one has a larger footprint, and hence protects a larger area.
Point (pun intended) being is that the lightning actually "strikes" the field and not the rod, thus minimizing the destructive kinetic and thermal impacts on the protected object.
If that mast is not metal, best to place a metal rod such that it is higher than the top of the mast. Remember lightning is very unpredictable, and can strike anywhere, not just the highest point, although that is more likely.
 
I know this subject comes up frequently --

Given that C-Dory's (and our Marinaut) are made of fiberglass, which is an insulator of sorts, and provided one tilts ones engine(s) out of the water, lowers the antenna and disconnects the antenna wire, is there really all that much risk in our boats in salt water during a lightning storm in a pilothouse boat? It seems to me that the most dangerous boats in lightning storms are open in design and have metal hulls, or are sailboats with metal keels. There is a lot of information on the web taken from Dr. Thompson's work, but it seems to me in my limited knowledge that attracting lightning via a temporary set-up with grounding plate in the water is not necessarily the most desirable thing to do. What are people's thoughts on this?

Rich
 
See my post from 2007. Nothing has changed my mind in the last 6 years. I agree that generally the C Dory is going to be safe--or as safe as possible. Antennas down, stay away from metal--anchor if possible. I have had minor strikes to my person three times. The last one we were on a friend's trawler--and on the flying bridge. I told the skipper we should shut down and get below in a very bad lightening storm. His response was to get as close to a sailboat going the same direction...I mean only a few feet from his bow to the sailboat's stern... (I was sort of hiding out of embarrassment)
A strike hit the sailboat mast--and all sorts of bad things happened to this boat--fortunately we didn't run it over when the sailboat engine stopped...

A lobe of this strike hit the Bimini frame next to me, and a small arch jumped to my shoulder and then to Marie who was sitting next to me. No damage to either of us. But the skipper got the message--and we went below and drifted until the storm was over...

We just stay below, get away from metal. Yes, a small open metal boat is more dangerous-so is a paddle board, wind surfer etc...
 
Rich-

My thoughts are pretty much summed up in the posts above, not much to add other than I think that one can conclude after reading them all that all one can do is outlined there.

Yes, one is much better off in a pilothouse boat. Make all the possible preparations/precautions, then get down out of the probable electric paths and wait it out.

Also, the addition of a lightening rod/pole/attractor, cable and grounding plate seems to just insure that the strike will be bigger, so adding all the extra gear is just "puttin' more powder in the musket!", so to speak….

Another thought: it would pay to keep a sharp eye out on the weather as much as possible, at least when near shore and shelter. Not much one can do about that 20-50 miles out in the Gulf, however!

Be safe, and strike up the………………………..band! :note :note :note :note :note :note :note :note :note :lol:
 
Lightning isn't fun. Being from SoCal, we're not used to lightning (or rain.) So, when we went through lightning in the South Pacific it was a new experience, mild enough so that we didn't learn the proper respect. Except to leave the area.

When we had the Our Journey on the East coast, we left St Augustine to go directly to Savannah and half way there a lightning storm caught up with us. There were strikes all around, and we were the only thing there with a 50' tall aluminum rod sticking up. We were immediately taught respect, and it was the first time I thought we would certainly sink. Called the Coast Guard and said I'd call back every 1/2 hour till we got out of there. Turned left towards shore and left the area. Never got hit and I don't know (or care) why.

So this either proves that luck beats skill or that God takes care of simpletons. We fit both cases.

No recommendations how the avoid lightning strikes except to stay away from them. The West Coast is good for that.

Boris
 
thataway":1qn82w1d said:
His response was to get as close to a sailboat going the same direction...I mean only a few feet from his bow to the sailboat's stern... (I was sort of hiding out of embarrassment)
A strike hit the sailboat mast--and all sorts of bad things happened to this boat--fortunately we didn't run it over when the sailboat engine stopped...
A lobe of this strike hit the Bimini frame next to me, and a small arch jumped to my shoulder and then to Marie who was sitting next to me. No damage to either of us. But the skipper got the message--and we went below and...

A relative of mine was told to hunker down near a sailboat during a lightning storm by a so-called expert. It seemed bad advice to me then, and after what you related, seems to remain bad advice. And that's the whole point of not wanting to attract lighting, or to be close to objects that are attractive in that regard such as sailboats. Incidentally, we were expecting a big lightning storm a few weeks ago, and we followed your advice: tilted the engine out of the water, put down the antenna, disconnected the coax from the radio, disconnected the GPS and Radar connections, and stayed inside and away from metal.

Rich
 
Sea Wolf":11e2kyg9 said:
Another thought: it would pay to keep a sharp eye out on the weather as much as possible, at least when near shore and shelter. Not much one can do about that 20-50 miles out in the Gulf, however!

Be safe, and strike up the………………………..band! :note :note :note :note :note :note :note :note :note :lol:

Good advice, Sea Wolf. I'm fearful of lightning and try to avoid it, but in the summer, a storm can pop up at any time. We do watch the weather, and there is no need to venture out if we know a front is due to pass through.

Boris,
New England is not as bad as Florida with respect to thunderstorms, but the weather has become more violent in recent years. So we try our best to follow the weather.

Rich
 
Both my wife and I reviewed this video a number of times and did not see a single point strike on the video.

Lightning will often have multiple lobes--some major and some minor. Also a near by lightning strike can send current thru the ground and damage be done in that fashion.

I have seen a number of destructive strikes--some at far too close range. There is damage done at the point of strike and at some times for some distance around that strike area.

Boat antennas and mast heads can be melted (temp can be as much as 50,000 degrees F.) In our boat which had multiple strikes (after we sold it, but still at our dock)--there was rigging damage, mast damage, and all of the electronics and electrical systems were destroyed.

A direct strike will cause burning in multiple patterns on a person. Clothing can burst into flame, cardiac arrest, brain damage and instant death may occur (some patients can be resuscitated--so CPR is always indicatedI).
 
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