Lightning Strikes

[noelex 77]

Originally Posted by zeehag

sabray---

ye wanna dictate right and wrong in a non exact science????
get reality oriented.
you lose.
is not an exact science, as medicine is not an exact science.
there are NO rules governing lightning strikes.
there are NO rules governing where or when or how intense is the damage from lightning strikes.
there is no right and wrong. get a reality check, guy.
...

Zeehag with respect you are misunderstanding the science.
The science behind lightning is well understood and proven. In my ways your analogy with medical science is a good one. For example it well established that smoking increases your risk of various diseases such as lung cancer. This does not mean that everyone who smokes gets lung cancer. Smokers are fond of quoting examples where people have lived a long life despite smoking. These cases are real and do not contradict the science.
In the same way not grounding your boat increases your risk of damage from a lightning strike and slightly increases your risk of getting hit. There are individual cases that contradict this general trend, like the smoker that lived to 100, or the person that never smoked, but got lung cancer.

Oh and if you are going to wear Crocks make sure the correct anti-lightning gibbits are attached. There are some cat based ones that probably help. I have an Australian flag on mine and so far have not been hit while wearing it so it might be worth a try

[sabray]

Alright we got through that one. Wow cat is back aboard so were all good.. Here is how I did not get hit. I threw a cat." I'm throwing it out there like the cat idea" . I threw the cat out there. For crocks I had to do arrogamie Took online class , cut the copper band connecting the mast to bond strap.
Thanks for all the help. This technique proven scientifically because no one who has done this has been hit.

[tropicalescape]

Originally Posted by noelex 77

Zeehag with respect you are misunderstanding the science.
The science behind lightning is well understood and proven. In my ways your analogy with medical science is a good one. For example it well established that smoking increases your risk of various diseases such as lung cancer. This does not mean that everyone who smokes gets lung cancer. Smokers are fond of quoting examples where people have lived a long life despite smoking. These cases are real and do not contradict the science.
In the same way not grounding your boat increases your risk of damage from a lightning strike and slightly increases your risk of getting hit. There are individual cases that contradict this general trend, like the smoker that lived to 100, or the person that never smoked, but got lung cancer.

Oh and if you are going to wear Crocks make sure the correct anti-lightning gibbits are attached. There are some cat based ones that probably help. I have an Australian flag on mine and so far have not been hit while wearing it so it might be worth a try

Smoking them damn cigars killed my grand dad...Rest in peace... jan 4 1913- sep 2005..DVC

[sabray]

My attorney thinks I should add this disclaimer. Suggestions of throwing a cat or bonding cats tongue to machinery is bad and should not be applied The science behind throwing a cat has not been proven and may violate local laws.i am sorry I suggested that I was tempted to tie my cats tongue to the drive shaft. I have not tossed and do not advocate tossing cats. Really sorry if I offended anyone. No cats were hurt or used during my experiment..

[reed1v]

Originally Posted by cat man do

So if lightening wants to take the past of least resistance doesnt it make sense that the boat with the best grounding system is most likely to get hit?
In this case it was the powerboat

not the size, but the mass that influences strikes.think empire state building. btw: common for big steel boats(think navy) to be hit by lightening. no big deal. acts as hugh ground and a faraday cage. again, your playing the odds. people have been struck by lightening through their car windshield, but that is just bad bad luck. still safer in the car than standing outside during a lightening storm. so you ground, stay inside, and stay dry. might also help splash some gin over the side to appease the gods. or just sacrific a virgin if you can find one.

[zeehag]

sabray--one doesnt throw the cat--one lets cat live on boat peacefully while wearing crocs and sailing thru multiple lightning storms for almost a year.
and i will not be unconvinced that t he act of attracting the lightning ith a lightning attractor sold in many marine stores is a foolish way to treat lightning--i choose to refuse to attract it to my boat-thus preventing the associated damages. remember lightning follows no rules.

[westwinds]

Here is the latest on the science of lightning in general and what is recommended for boats.

“New Concept for Lightning Protection of Boats-Protect a Boat Like a Building” is a publication by Ewen M. Thomson, Ph.D. that outlines the ideas that were the rationale for the new National Fire Protection Association (NFPA) standards, NFPA780-2008, National Fire Protection Association, Chapter 8 boats and lightning. The ABYC marine standard Lighting Protection Standard E-4 was the foundation for previous standards for NMMA, a boating organization for manufacturers of boats; however, the latest ABYC rewrite has been downgraded to the Technical Report TE-4 and is not used by NMMA anymore. http://www.marinesurveyorschool.org/seminar_files/Lightening%20Protection.pdf

Thomson's “New Concept for Lightning Protection of Boats-Protect a Boat Like a Building” http://www.marinelightning.com/EXCHANGEOct2007Final.pdf document addresses problems with lightning with respect to power boats, but the proposal for ‘like a building’ was too complex for a power boat so instead multiple grounding terminals use existing metallic fittings such as through-hulls, propeller struts, and rudder posts. It seems to me that using existing fittings is not the same as multiple lightning rods running to a large ground that surrounds a building and that a sailboat mast is higher than the ten inches for a building lightning rod and that most buildings are not made of fiberglass, but maybe I am being too critical. Bonding evcrything together probably makes sense because the cone of protection on a sailboat is so large that it will protect anyone touching a wheel, engine controls, pulpet that is grounded?

The National Fire Protection Association (NFPA) standards, NFPA780-2008 is here: www.papasys.com/attachment.php?attachmentid=522. See Chapter 8. There is also a newer standard by NFPA780-2011, now Chapter 10, but it is essentially the same except for a new provision to have multiple grounding electrodes that are bound together rather than a single one square foot one. NFPA780-2011 is harder to read because you have to make sure you have Java downloaded and active on your computer to view it to prevent copying of the document. If you want to view it then see: http://www.nfpa.org/onlinepreview/online_preview_document.asp?id=78011#

[zeehag]

i do not need furthr education in the science of lightning beyond that which i already have been taught by experts in everything--i KNOW lightning--was a very very close call aT AGE 3 YRS --one never forgets that stuff, and makes one study it closely from a personal perspective--i dont need the words of folks who never sailed thru it or lived in it, literally, which is what happens on a boat-you LIVE it.... i am sure the individuals who SAY to place crap on your boat as if it were a building have never been sailing thru lightning--i refuse to participate in the scam sales of alleged prote3ction when i already know that answer--i live it , i sail in it--
many souls will say ANYTHING for SALE OR TO FURTHER THEIR CAUSE. - i donot follow that either.
do you buy snake oil also????? if not--best be ready to so do --could help your lightning struck and sunken boat. just ask the NASA ENGINEER IN SLIDELL WHO HAD HIS BOAT HIT AND SUNK 2 TIMES IN 4 YRS
is impressive.

[reed1v]

Originally Posted by zeehag

sabray--one doesnt throw the cat--one lets cat live on boat peacefully while wearing crocs and sailing thru multiple lightning storms for almost a year.
and i will not be unconvinced that t he act of attracting the lightning ith a lightning attractor sold in many marine stores is a foolish way to treat lightning--i choose to refuse to attract it to my boat-thus preventing the associated damages. remember lightning follows no rules.

au contraire, lightning does follow rules. we can only predict in a probabilistic fashion since we dont know all the conditions as they occur in real time. to advocate ignoring the rules is a real disservice to cruisers. but if you really believe in going to voodoo doctors for medical treatments, then at least dont encourage others to do the same.

[micah719]

Science, eh? Depends if it's real science, or just dressed up like it. When there are conflicting reports from "scientists", I suspect witchdoctors, or as Capn Zee said, snakeoil sellers.

I read an article just yesterday about how lightning seeks to discharge to the surface of the water, yet this new spin suggests treating a boat like a house and using the existing fittings...subsurface. Either one of them is wrong, or both of them.

As to medicine being a science....discount the giant pharmaceutical corporations and their pet politicians, the suspicious increase in certain diseases such as parkinson's, alzheimer's and MS ever since nuke and bio-warfare testing, and the disturbing hints of desired mass genocide from the likes of Aldous Huxley, Prince Edward, Bill Gates and the Rio +20 gang...and the astonishing things still being discovered about the complex human body, such as "junk"-dna not being junk after all; I think I'll stay away from lighting experts, politicians, and doctors.

[tropicalescape]

Originally Posted by reed1v

au contraire, lightning does follow rules. we can only predict in a probabilistic fashion since we dont know all the conditions as they occur in real time. to advocate ignoring the rules is a real disservice to cruisers. but if you really believe in going to voodoo doctors for medical treatments, then at least dont encourage others to do the same.

The only rule I ever saw it follow was that it sometimes strikes..I have a grounding system on my boat but, I can still see the other side of not attracting it..but at the end of the day you still have a big aluminium pole sticking up ...what to do?..DVC

[zeehag]

reed1v--i AM a cruiser--i LIVE in lightningville and sail there, and have sailed in florida--where the lightning isnt nearly as much nor as strong as here in west coast mexico. iamnot a lightning studying desk jock nor a commenter sans knowledge. where do you SAIL, reed1v??? DO YOU SAIL IN LIGHTNING STORMS??
i do and i have done so for 3 yrs of it so far. and i will probably sail in more lightning.
lightning follows no rules.

" I think I'll stay away from lighting experts, politicians, and doctors." you are a most wise man....

[Jon Hacking]

Originally Posted by noelex 77

Lightning strikes are too variable to draw any conclusions from the results of a few boats. The science, however is clear and unequivocal.

1. Grounding reduces the damage to to a boat and its occupants, usually considerably.
2. Grounding (slightly) reduces the chance of being hit.

If someone can present a view, from a credible expert, that contradicts these simple statements, present it. I am all ears.

Noelex, I'm not at all sure that the science is clear. While I agree with your #1, my (fairly casual) survey does not bear out your #2. I would say that grounded boats tend to take less damage when hit, but also tend to be hit a bit more often.

Our own experience (18 years cruising) is a pair of near hits (that is, they probably did not hit our boat) - 1 in Langkawi, Malaysia in 2011 that took out our radar & autopilot control head (not the brain) but didn't affect the VHF, SSB, wind (or other) instruments, or the computers. In 1985 in the Caribbean we took another near hit that zorched the wind instruments & the VHF (all the electronics that boat had) but then the VHF came back to life ~3 hours later. Very strange. Both of those boats were cats but neither had grounded rigs, which I think is why they weren't hit harder (but I honestly don't know).

[reed1v]

touchy folks here. well, each to their own. guess knowledge is whatever you want to believe. and yes, i have sailed in very charged areas: itcz(look it up), south china seas, philipines, western african coast, and columbian coastal areas. also mountaineered in stormy conditions. working on my 7th decade of existence ; so been there, done that. lightning is like cigarettes: may not hurt you but you ignore basic knowledge at your peril. gee, think i will turn on the old ham radio now its lightning outside.

[micah719]

Anyone tried a Farady cage to keep their vital electronics in during electrical storms?