New Study on Lightning & Boats

[rebel heart]

DOMINO 20: Lightning Survey Results

&

DOMINO 20: Considerations for Lightning Protection

Guy did a decent amount of research and went beyond "put a up a dissapator or not" and "how do I ground the boat or not".

[Paul L]

It is an interesting set of articles, although it is mostly pretty much anecdotal info. I know some of the boats involved in the survey. The one mentioned as a steel trawler with a bolt-out-of-the-blue was a 46ft steel sloop. I believe they got hit in Panama - a not uncommon experience. The info on the surge protectors is interesting. It looks like a pretty cheap way to add some electronics protection.

[rebel heart]

Originally Posted by Paul L

It is an interesting set of articles, although it is mostly pretty much anecdotal info. I know some of the boats involved in the survey. The one mentioned as a steel trawler with a bolt-out-of-the-blue was a 46ft steel sloop. I believe they got hit in Panama - a not uncommon experience. The info on the surge protectors is interesting. It looks like a pretty cheap way to add some electronics protection.

I think what I found most interesting was just the lightning distribution map which I'm sure has existed for a long time. But the boiled down rule #1 is: don't hang out in places with a lot of lightning.

[Paul L]

That's easier said than done. It just may mean you have to go way north during the tropical hurricane season. But even then, I''ve seen some nasty summer t-storms in the Chesapeake. If you are a tropical, warm weather cruiser, you are going to get into lightening storms. When we were in Central America I knew personally at least 5 boats that got hit. It seemed like a really high percentage. One I was standing in my companionway and saw the cat next to me take a hit to the mast. I wasn't more than 150 feet away. Another friend took a hit while they were off the boat. When they manually picked up the anchor -- windlass was fried - one side of the shiny stainless anchor was all rainbow, burnt metal colored. Both boats lost a lot of electronics, with no other damage except a loss of the VHF antenna.

[Jim Cate]

Originally Posted by rebel heart

I think what I found most interesting was just the lightning distribution map which I'm sure has existed for a long time. But the boiled down rule #1 is: don't hang out in places with a lot of lightning.

Eric, did you notice that neither Oz nor NZed appear on that chart? I have seen lightning in both countries (lots!) so be warned!

But some interesting, if sketchy, statistics are presented. Thanks for posting the links.

Cheers,

Jim

[dominoMarie]

Originally Posted by Paul L

It is an interesting set of articles, although it is mostly pretty much anecdotal info. .

Yep, surveys are "anectdodal" by definition. For hard science info, refer to the links in the 2nd article. Thanks for the feedback!

[Paul L]

Originally Posted by dominoMarie

Yep, surveys are "anectdodal" by definition. For hard science info, refer to the links in the 2nd article. Thanks for the feedback!

The anecdotal comment was not meant as a negative to your write up. Just that data that is verifiably real and at the same time directly applicable to cruising boats is very hard to come by. The insurance data is interesting, but it covers much more US centric boats and boats that are in marinas -- and of course boats that are reasonably insurable. So I don't see a lot of hard science that can be applied to cruising boats on lightening. Anecdotal data is nice because it lets us pick and choose what we want to hear from it and end up with a pre-decided conclusion. The 'out-of-the-blue' strike you mentioned occurred offshore of Nicaragua in an area and time of year when there is almost continuous thunderstorms. We went down that coast a few months after the metal boat ended up with a fire in a cable bundle that was likely caused by lightening. Probably the more surprising question is why don't more boats get hit in that area.

I'm on the side of at least supplying a good path to the water for a strike -- based on the anecdotal info I have.