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angus99

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BOATUS just published an article on the prevalence of lightning striking boats, vulnerability by type of boat, etc. All based on 10 years of claim data. Trawlers fared pretty well compared to -- big surprise -- sailboats, and particularly multi hulls.

Striking Lightning Facts - Seaworthy Magazine - BoatUS
 
Thanks for the link!
We had a 43 ft sailboat get hit years ago. Lost a whole season getting things fixed. So there's another reason why moving to the trawler was a smart choice. Less risk of being hit.
 
We had a Columbia Contender sink at the dock at my sailing club in Tennessee after a lightning strike. It looked like bird shot had been fired through the hull. Why it chose to strike a 24-ft boat with a fairly short mast when much taller masts and trees were all around it has always baffled me.
 
My boat is surrounded by three sailboats with masts taller than mine. I wonder how effective lightning rods are in reducing strikes.


img_301078_0_29286ff14f2efea401e1d053a6276077.jpg
 
I wonder how the data would pan out if they had the location of each type vessel in relation to land, civilization, other vessels, etc...etc.

I have seen my share of lightning and maritime strike damage and I would definitely say it is way more random than the basic grouping in the article.

Could the skewed data reflect that those types of vessels higher in strike percentages may also be out by themselves in open water more than the others?

May have to write for clarification....
 
600,000 volts discharging 60,000 amps hotter than the surface of the sun and travelling at the speed of light ! There is no defense, it goes pretty much where ever it wants .
 
I had a cousin killed by lightning when I was about 10 or so. It wasn't raining. Wasn't thundering. And no previous signs of lightning, not even in the distance. She was just standing in the yard under a large tree. 1 strike and got her in the head and she instantly died. It was just way ahead of the storm.
 
Greetings,
Mr. mp. Actually lightening rods increase the risk of a strike. They generate "streamers" which "attract" lightening strikes. FYI...
Blitzortung.org – lightning map Europe – thunderstorms and lightning strikes

Like "electrolysis" and "osmosis" there is a huge amount of questionable mythology surrounding lightning and streamers in marine circles. Lightning rods do not generate positive streamers, they simply try to direct such streamers (which occur with or without a rod) caused by the massive force of the negative lightning charge to a strong enough ground to avoid other damage. They are one of the oldest and most proven (although not perfect) method of lightning damage mitigation.
 
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I was always taught lightning rods or the more famous Florida Power and Light bottle brush design were to bleed off potential (static abhors a sharp point)....thus reducing the possibility of all of the components of a strike.
 
I was always taught lightning rods or the more famous Florida Power and Light bottle brush design were to bleed off potential (static abhors a sharp point)....thus reducing the possibility of all of the components of a strike.

Studies have long proven lightning dissipators (bottle brush) are ineffectual and the science behind them questionable at best.
 
True but that's what they were designed for...so yes with no real deterrent ...the next best is a Faraday cage/grounding system around you with the capacity to deflect/carry the strike to ground.
 
True but that's what they were designed for...so yes with no real deterrent ...the next best is a Faraday cage/grounding system around you with the capacity to deflect/carry the strike to ground.

Agreed the Faraday is by far the most effective .... tough to put around a boat tho' :)
 
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You talking about the leader, the main charge or the return strike ? all different speeds. What you have to remember is that much science related to lightning is still in the realm of "theory" and why there is still so much snake oil sold into the market. I've taken courses with two of the top people in the field and know a third, none of them agree !
 
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I had a cousin killed by lightning when I was about 10 or so. It wasn't raining. Wasn't thundering. And no previous signs of lightning, not even in the distance. She was just standing in the yard under a large tree. 1 strike and got her in the head and she instantly died. It was just way ahead of the storm.

We heat our house with wood. Mother nature drops plenty of trees on our place which I convert into firewood. Sitting here typing in front of a nice warm fire. :thumb:

Unfortunately, our house is on a small hill, not that tall compared to the surrounding terrain but we are the tallest point for a couple of miles. I think many of the trees mother nature provides us has been taken out by lightning. :nonono:

For many years, I would split wood under a large oak tree at the back of our house. I would split and stack the wood under that tree and the tree would provide shade during the summer. :thumb: A few years back a storm front was on the way and it was supposed to arrive around 2:00pmish. I had a bunch of wood to split but I did not want to start working and not finish the job. There was no way I could finish by the time the front arrived so I called my parents.

Before I called I checked radar and the front was 20-30 miles away. At our house the sky was perfectly clear. Not a cloud in the sky. I was on the cell phone talking to my parents when I took a look out the west side of our house to see if I could see the front. Not a cloud to be seen.

At that moment, everything went white. Perfectly WHITE. Followed by one heck of an explosion. :eek:

Power flickered out but returned quickly. Internet was gone for a short while. My cell connection was gone.

Lightning had hit the oak tree I would have been working under splitting wood. :eek::nonono: Bark was blown 100 feet from the tree but the tree only had a small surface crack. The tree had green leaves for another 2-3 months, when all of the sudden, in one day, ALL of the leaves went brown.

I don't think I would be alive if I had decided to split wood that day. :eek:

We had no damage to the house at all. :thumb: WHY that tree got hit and not others is a mystery. There are plenty of other oaks near that tree. Some much taller and many the same size. WHY that particular tree got hit is a mystery.

Again, not a cloud in the sky and the front was 20-30 miles away.

When the front did arrive, it dropped tornadoes which torn up a city near by, and further east, killed three people. One of the dead was a coworkers aunt whose house was destroyed by a tornado that killed her and a neighbor. If that tornado had gone maybe 100 yards east or west of its path, the people would not have died.

Later,
Dan
 
This was 2 years ago off the back deck of Hobo when she was anchored across from Clarence Town. A bit of a pucker factor. No one was hit fortunately.
 

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Here is an outfit that has developed lightning protection for boats: Marine Lightning Protection Inc. The systems are similar to what is used on buildings.

I had an experience some years ago where an alarm system in one of my buildings kept being taken out during storms. Solved it by installing a new ground rod for the building and surge suppressor on the panel box.

I haven't seen any of these systems installed on boats I have surveyed yet but I am sure the day is coming. Expecially catamaran sailing vessels.
 
True but that's what they were designed for.

Just because they were designed for it doesnt mean they are effective at it. I can also second that he science behind them comes from those with financial ties to the companies manufacturing them. Outside of that circle it seems to have been settled that they are entirely innefective. It seems to me thay are still being sold with profit to the seller as the only benefit.

The best protection you can have still is a plain old lightning rod with thick enough gauge and properly routed to a grounding plate. It will not necessarily protect the electronic equipment but it's the best odds that any occupants will have.
 
Speed of light = 186,000 mps or 671 million miles per hour
 
The best course of action is to ground all metal on your boat to a grounding plate below the waterline. This gives the lighting a clear and unobstructed path to exit the hull of the boat. without the ground plate exposed to the salt water the lighting find its own way out of the boat causing catastrophic damage to the hull and sinking of the vessel.
 
I believe the current thinking, and definitely mine, is the grounding/bonding system of a boat is no where's near adequate for lightning.

Encouraging lightning to enter the boat and exit through an inadequate ground plate can be worse than nothing. But a good bonding system is necessary for other reasons.

The best approach is to give tbe lightning a low resistance path outside tbe boat or one just inside the boat to near but above the watetline that would take it back out to tbe water.

The bolt wants to get to tbe opposite potential with the least resistance. If your boat from water to tippy top does that, you might be included in tbe fun.

I would not encourage that in any way other than surface wise on the exterior of the vessel, and only to barely above the waterline.

If you encourage lightning to strike by creating a low resistance path, and it fails because it is "undersized" like a fuse in a shorted circuit, well, think about what the lighning might do next.

Event the heaviest "lightning systems" I have seen could barely safely divert a tiny spike.
 
The best course of action is to ground all metal on your boat to a grounding plate below the waterline. This gives the lighting a clear and unobstructed path to exit the hull of the boat. without the ground plate exposed to the salt water the lighting find its own way out of the boat causing catastrophic damage to the hull and sinking of the vessel.



This recommendation is given with personal experience. When we had our 2005 41’ Hunter Deck Solon Sailboat we traveled up the east coast from Florida to New England each summer. Putting over 3500 miles on her. We have been directly hit by lightning three times. Each time some, but not all, of our electronics were damaged. But we never suffered any damage other than the electronics. We have friends that had their hull blown open and sunk. Others have had their hulls cracked and damaged. So when I tell you to wire all your metal to a grounding plate, below the water line, that is exposed to the salt water (don’t paint it) it is real life experience talking. [emoji41]
 
Please note that lightning, like most all other atmospheric events, comes in different intensities. I've had equipment survive with direct strikes, but be careful in extrapolating what worked a few times to "I can survive all lightning hits because of what worked before". Lightning current can vary over a few orders of magnitude. Sometimes enough current to melt 1/4" plate steel, and small enough to be carried by #8 aluminum wire.
 
Still getting details, but pretty sure a boat here in Prickly Bay Grenada got hit yesterday afternoon. I saw the flash, and a strange poof of brownish smoke rising from the area that lingered for some time. Obviously a sailboat as I am surrounded:)
 

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