Lightning

The friendliest place on the web for anyone who enjoys boating.
If you have answers, please help by responding to the unanswered posts.

Moonstruck

Guru
Joined
Nov 27, 2008
Messages
8,276
Location
USA
Vessel Name
Moonstruck
Vessel Make
Sabre 42 Hardtop Express
I did a search of the site, and did not find any specific threads on the subject of lightning. Is anyone doing anything to protect against lightning or the effects of a lightning strike? We have had many severe thunderstorms this season. Some have been extremely violent. Just wondered if I am missing something that I should do.
 
My understanding is that any lightning ground system needs to be separate from all other grounding systems on the boat. So if you're going to use the mast as part of that system, the anchor lights or other mast electronics can't use the mast for ground. They should be separately grounded with their own grounding wire.

It's always safer to pre proactive anda lower your profile when you're at the marina by lowering your antenas and such if you can.
 
There are drastic and expensive ways to cage your boat...just unhooking your electronics is far cheaper even if a few get whacked from time to time unless you have $20k plus systems aboard.

Having observed lightning for a lifetime of boating, 20+ years as a USCG helo pilot (and flying in way too many thunderstorms), and another 10 years on the water as an assistance towing captain....I see lightning as a roll of the dice...way too many variables and the "big sky" theory to worry about it. Protect yourself/loved ones and have good insurance on your boat/electronics. If on a cruise and thunderstorms are predicted....get in or near a marina and the chances of you getting hit are greatly reduced.
 
I did a search of the site, and did not find any specific threads on the subject of lightning. Is anyone doing anything to protect against lightning or the effects of a lightning strike? We have had many severe thunderstorms this season. Some have been extremely violent. Just wondered if I am missing something that I should do.

I posted a thread (02/01/11) that started out as a question about whether flybridge radar towers painted a good radar target themselves, and the discussion moprhed into some ineresting accounts of lightning/trawlers.


Search RADAR/LIGHTNING

KJ
 
Last edited:
Go fly a kite Don, but not before handing Lou the video camera!

(another "Hold my beer and watch this!" moment)
 
This link seems to have some good info. I bought a set of electrodes from him and haven't been hit by lightning since. I may even get around to installing them someday. ;-)

Marine Lightning Protection Inc.
 
If you have a trawler, the safest place to be is inside a ring of sailboats! ;)

There are dozens of articles (and opinions) on the subject on the Internet. Do a web search, read a few, then decide what you think is reasonable.
 
This link seems to have some good info. I bought a set of electrodes from him and haven't been hit by lightning since. I may even get around to installing them someday. ;-)

Marine Lightning Protection Inc.

:lol::lol::lol::lol::lol::lol:
Thank you for the early morning laughs!!
 
My boat got popped a few years ago. I think the batteries exploded. When I rebuild the batterie station I am going to buy some nice container that limit the amount of gas and or vent that area with a little blower, or in the very least mount a fire extinguisher pointing at them.
 
My boat got popped a few years ago. I think the batteries exploded. When I rebuild the batterie station I am going to buy some nice container that limit the amount of gas and or vent that area with a little blower, or in the very least mount a fire extinguisher pointing at them.

You think the batteries exploded?

That should be pretty easy to determine.
 
It is my opinion that with respect to lightning that prevention is better than the cure .

My friend lost his electronics when lightning hit his VHF antenna even when he was on the move.

Towards that goal, I always lower my VHF antenna when not needed the horizontal to reduce the risk.
 
Surounding your boat with sail boats maybe not so good an idea.

While my boat was moored in Portage Bay" in Seattle" when a 40' Valiant sailboat was struck. The sail boat was seperated from my boat by a 40 Advanti express cruiser. The lightning exited the sail boat at the water line burning a 1-1/2" hole in it and blew all of the electronics and electrical systems out of the Advanti, jumping maybe 10'. The only damage to my boat was the shore power cord a blown fuse at my shore power receptacle. The Valiant was completely rebuilt. The area around Portage bay is hilly and the Valiant was docked about 200' from the shore and tall trees and power lines Why the Valiant? I guess when it's your turn it's your turn. Why would the lightning goes sideways rather than directly into the water?
 
Last edited:
It is my opinion that with respect to lightning that prevention is better than the cure .

My friend lost his electronics when lightning hit his VHF antenna even when he was on the move.

Towards that goal, I always lower my VHF antenna when not needed the horizontal to reduce the risk.

Lowering your antenna is probably not really doing a lot to prevent a strike...a strike if it is imminent in your area is probably going to happen. Your lowering the antenna may prevent a "spike" from jumping over...but if the strike is close by and your radio isnt disconnected and possibly in a metal box...the EM may destroy it anyway.

Thinking lightning always hits the tallest object has been disproven many a time...it's all about the potential and where it's the greatest and the best path. While never being next to the tallest object is a great idea...being near it doesn't mean you are safe either...
 
Last edited:
Hello psneeld.

What you say is absolutely true about lightning strikes.

Round and round she goes where she stops no body knows.

I have a 40 ft Amateur radio tower on my property, we took a hit it was not at the top of the metal cage as one would expect the spike hit and shattered a large ceramic insulator part way down one of the lower guy wires.

You no doubt have notices lightning rods at the highest point of some buildings makes you wonder why they were installed there.
 
Hello psneeld.

What you say is absolutely true about lightning strikes.

Round and round she goes where she stops no body knows.

I have a 40 ft Amateur radio tower on my property, we took a hit it was not at the top of the metal cage as one would expect the spike hit and shattered a large ceramic insulator part way down one of the lower guy wires.

You no doubt have notices lightning rods at the highest point of some buildings makes you wonder why they were installed there.

Big difference in protection systems that either dissapate the potential, carry the strike or just cage and protect the interior....totally random pieces and parts like boat antennas may or may not do anything at all.

So I have no wonder why rods are up there as I have studied lightning systems and their effectiveness since I lived on my first sailboat in Ft Lauderdale back in the early 80's. Flying helicopters around in it for 20+ years and then being in charge of the safety program for USCG Aviation also required a lot of research and though on the subject. A good friend of mine had a severly damaged Falcon Jet from a stike over Gulfport, Miss. I got to read the entire safety report on it..fascinating what all the experts "think" happened.
 
Our idea of dealing with lightning is not to be around it - which is not always possible. About 10 years ago, offshore, we had a front coming at us with lots of thunder and lightning. We use a PC for navigation so to protect the laptop, we put it in the oven figuring that it would be well shielded. A couple hours later, I lit the broiler for dinner. About 10 minutes later I checked to make sure that it had lit - and realized that the laptop was still in the oven. :cry:The top of the laptop was distorted and partially melted. After a few words and beers, we turned it on and it worked. :dance: The idea of shielding the electronics is sound but we haven't used the oven as a shield since.
 
Our idea of dealing with lightning is not to be around it - which is not always possible. About 10 years ago, offshore, we had a front coming at us with lots of thunder and lightning. We use a PC for navigation so to protect the laptop, we put it in the oven figuring that it would be well shielded. A couple hours later, I lit the broiler for dinner. About 10 minutes later I checked to make sure that it had lit - and realized that the laptop was still in the oven. :cry:The top of the laptop was distorted and partially melted. After a few words and beers, we turned it on and it worked. :dance: The idea of shielding the electronics is sound but we haven't used the oven as a shield since.


:rofl::rofl::rofl::rofl:
 
There are drastic and expensive ways to cage your boat...just unhooking your electronics is far cheaper even if a few get whacked from time to time unless you have $20k plus systems aboard.

Having observed lightning for a lifetime of boating, 20+ years as a USCG helo pilot (and flying in way too many thunderstorms), and another 10 years on the water as an assistance towing captain....I see lightning as a roll of the dice...way too many variables and the "big sky" theory to worry about it. Protect yourself/loved ones and have good insurance on your boat/electronics. If on a cruise and thunderstorms are predicted....get in or near a marina and the chances of you getting hit are greatly reduced.
PS, Helo pilot? That's awesome. Where we're you stationed? Rescue missions I assume?
 
PS, Helo pilot? That's awesome. Where we're you stationed? Rescue missions I assume?

Navy Flight school, Miami, Polar Operations (3 trips Acrtic/ 1 trip Antarctic Icebreakers), Cape May, Nj 2X, Kodiak AK, Wash, DC.

USCG does all its missions when airborne...:D
 
You think the batteries exploded?

That should be pretty easy to determine.
Well after removing 5 dumpsters that hold about 20 yards of burnt trash I found the batteries and they were burnt, they were intact on the bottom but the tops were missing. I don't really know enough about lightning strikes to know what blows up. Just a laymans opinion.
 
I did a search of the site, and did not find any specific threads on the subject of lightning. Is anyone doing anything to protect against lightning or the effects of a lightning strike? We have had many severe thunderstorms this season. Some have been extremely violent. Just wondered if I am missing something that I should do.

Moonstruck.

You have asked.

"Is anyone doing anything to protect against lightning or the effects of a lightning strike? ".

Here is my take on your question for home and boat.

Verify that you insurance policy covers lightning damage.

Insurance companies will not support claims by people who make no effort to reduce liability, however there are a few exceptions.

All electrical storms start somewhere , they don't all come from the parking lot at Wall-mart , some storms can have there beginnings mat be just across the street from you ,this is also depending on where you live on the planet.

To avoid the loss of, or damage to, our electronic equipment and prior to an electrical storm we systematically un - plug all incoming electrical supply cables and also including incoming transmission lines to items such as Cable TV ; Stereo systems ; Telephones ; Micro waves; Computers and so on !

Don't be lulled into a of false sense security by thinking that a 15 Amp electrical power bar having voltage surge protection will save you equipment because it will not.................. Pull the Plug.

http://www.trawlerforum.com/forums/images/trawler/smilies/sk/dance.gif
 
Thinking lightning always hits the tallest object has been disproven many a time...it's all about the potential and where it's the greatest and the best path. While never being next to the tallest object is a great idea...being near it doesn't mean you are safe either...

Now, you've done it! I thought I was safe here. Now, I'm paranoid again.:banghead:

img_95723_0_f5e7075e3ec371e81defcdb695df6296.jpg
 
Good info in Chapman's on how to construct a Faraday cage for your boat.
A cone from the highest point to the water.
It needs a separate ground from mast to keel and a path to follow.

In 30 years of boating in the Prince William Sound I have yet to see lightening or even a thunder storm.
They get them in the interior of Alaska just not on the coast.

SD
 
Last edited:
Now, you've done it! I thought I was safe here. Now, I'm paranoid again.:banghead:

img_95803_0_f5e7075e3ec371e81defcdb695df6296.jpg

The night before last we had an all night lightning and thunder storm the light show was nearly comparable all to the 4 th july events for the last 99 years.

We had one hit but not where you would normally expect.

Here is a list of potential targets.


4 Police 100 ft steel radio towers
4 commercial radio station steel towers
2 Power station 80 ft exhaust chimneys
1 waste disposal incinerator chimney up 120 ft
1 Cast steel 245 ft Lighthouse. big target
A big bunch of city steel buildings , 2 all glass and steel.
A big bunch of cell phone towers
The Governors mansion with two towers
The house of Parliament house with two towers
1. 40 ft steel to ham radio grounded steel tower 280 ft above sea level , had two recent hits >>>>> its mine.
Miles of Airport and Prison chain link fences
6 super large steel fuel storage tanks.

You may say that lightning does not strike twice, don't you believe that one
our 245 ft Lighthouse takes lots of hits ,but not this time.

Where did it hit ?

The lightning took out a utility pole transformer located next to a steel water way swing bridge.

Why did the bridge not take the hit ?

Step right up Ladies, pay your money and take your pick.

Question : If lightning takes the path of least resist then why is fork lightning jagged and random.
 
That does it. I will just move the wheel down to the lower cabin level. Maybe Northern Spy will let me know where he gets his periscopes and hats.:socool:
 
The night before last we had an all night lightning and thunder storm the light show was nearly comparable all to the 4 th july events for the last 99 years.

We had one hit but not where you would normally expect.

Here is a list of potential targets.


4 Police 100 ft steel radio towers
4 commercial radio station steel towers
2 Power station 80 ft exhaust chimneys
1 waste disposal incinerator chimney up 120 ft
1 Cast steel 245 ft Lighthouse. big target
A big bunch of city steel buildings , 2 all glass and steel.
A big bunch of cell phone towers
The Governors mansion with two towers
The house of Parliament house with two towers
1. 40 ft steel to ham radio grounded steel tower 280 ft above sea level , had two recent hits >>>>> its mine.
Miles of Airport and Prison chain link fences
6 super large steel fuel storage tanks.

You may say that lightning does not strike twice, don't you believe that one
our 245 ft Lighthouse takes lots of hits ,but not this time.

Where did it hit ?

The lightning took out a utility pole transformer located next to a steel water way swing bridge.

Why did the bridge not take the hit ?

Step right up Ladies, pay your money and take your pick.

Question : If lightning takes the path of least resist then why is fork lightning jagged and random.

It only takes the path of least resistance where a strike is going to occur
due to the electrical potential difference between atmosphere and ground...otherwise every town on the planet coule just erect one tall tower and lightning would never be an issue.

No potential great enough...no strike. Ligtning rods are there to "bleed off" potential...not take the strike.
 
The summer storm season is here. Last week we were anchored in front of Clarence Town, Southern Bahamas. The catamaran on the right went dark during one of the strikes. I don't know what else they lost but the storm sure got our attention. :hide:
 

Attachments

  • L1.PNG
    L1.PNG
    7.6 KB · Views: 80
  • L2.jpg
    L2.jpg
    25.6 KB · Views: 77
  • L3.PNG
    L3.PNG
    169.2 KB · Views: 71
  • L4.jpg
    L4.jpg
    34.3 KB · Views: 80
  • L5.jpg
    L5.jpg
    23.8 KB · Views: 78
  • L6.PNG
    L6.PNG
    2.3 KB · Views: 73
I've taken a couple of courses on lightning taught by recognized "experts". The one thing they agree on is that lightning does not take the "path of least resistance" it takes all "paths" and can jump significant distances to find another path as someone already mentioned.

One thing that struck me in these courses was the constant references to "theory" in that the "experts" acknowledge that much of our thinking on lightning is just that, "theory" and there is little that is accepted as absolute.

Having investigated a few strikes (i'm no expert), some that made sense and some that defied all the rules. I have come to the conclusion that 60,000,000 volts discharging 60,000amps, hotter than the surface of the sun and travelling near the speed of light .... pretty much goes where it wants despite the efforts of mere mortals with their grounding cables, sintered bronze ground plates, ion disipators and all the other snake oil sold.
 
Last edited:
47 foot catamaran sailboat get struck here 2 weeks ago it had a 70 foot tall mast. Tow boat was towing the boat from Key West to Fort Lauderdale for repairs I think it's good not to be the tallest boat in the harbor
 
Is a lightning rod worth it?

img_156512_0_29286ff14f2efea401e1d053a6276077.jpg
 
Back
Top Bottom