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PostPosted: Wed Jul 02, 2014 11:33 pm 
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.....or have you known anyone to have suffered this?

There is a bit here and there on the forums, but it's more about grounding theory, close calls and third or fourth hand accounts. Does anyone here have personal experience or know of anyone close to you who has actually had a hit on their boat?

FWIW....I live in Florida; the lightning capital, and I am very curious about this.....I am a brand new AI owner, a relative novice, and I intend to spends LOTS of time on the water this summer and fall.

Any detailed stories pertaining to such an event and/or preventative mods are welcome, even if they are second or third hand.


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PostPosted: Thu Jul 03, 2014 7:24 am 
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Location: Sarasota,Key West FL
Living in south Florida in the summer lightning storms are pretty much a daily occurance every afternoon along with torrential rain then an hour later it's sunny and dry. I think if you are 10-15 miles from launch this can be a problem unless you have the ability to get out of dodge fast, thus the reason I have emergency outboards mounted on my TI, and have never been out in open water in the last 4+ yrs without the motor at the ready. Most small outboards weigh between 20 and 27 lbs and when tilted up, in the scheme of things that small amount of additional weight means nothing especially on a TI.
I've been out several times with huge winds, waves, and lightning all around me, not a fun experience, and I try to avoid whenever possible. I think the trick is to monitor the weather closely and alway be prepared to get back in if necessary.
Bob


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PostPosted: Thu Jul 03, 2014 8:03 am 
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Unlike Fusioneng, I will never put a motor on my AI (different strokes for different folks, as they say.) To be honest, there have been times when I at least thought it would be nice to have a motor--like last spring on a camping trip to Middle Cape-East Cape Sable and the winds were zero all day long with a fully loaded boat and an 11-mile pedal ahead. I do not sail in S FL in the summer (heading for the Rockies tomorrow!) No question you have to use common sense. Usually here in the Miami, S FL area, thunder storms build up by early afternoon. Yesterday about 11 AM, with a relatively open sky, a bolt hit so close and was so loud, I thought a house had blown up, literally. But, when I went outside, nobody was screaming, lawn mowers in the distance were still humming, and everything seem normal with blue sky and a few small clouds. So, I would be careful about going out in this time of the year. I think I would want mostly clear skies with a significant breeze.

Keith

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PostPosted: Thu Jul 03, 2014 9:38 am 
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I have been told that lightning won't strike a sailboat mast. While I'd like to believe that, lightning can and does strike carbon fiber fishing rods being held by anglers in boats. So, unless lightning can distinguish between a carbon fiber fishing rod and a carbon fiber sailboat mast, I tend to err on the side of caution.

If I were to get caught out far from shore in an approaching storm, I'd consider de-stepping the mast, which isn't hard to do on these boats even while on the water. On the other hand, you might need your sail to help negotiate and wind or waves. It's a tough call.


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PostPosted: Thu Jul 03, 2014 9:42 am 
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Is the mast on the AI and TI conductive? I think this could make a difference in how safe these are - my opinion is that a conductive mast would be safer because you KNOW WHERE the lighting strike will go. If the mast is conductive, chances are that the strike will go to the mast rather than the top of your head.

Sorry to the OP since I only heard this on a forum (not actual experience) but this story involved a Laser that got struck in Florida. The strike went to the mast and exited at the bottom of the mast and then to the water surface. The charge very easily ionizes air so jumped from the bottom of the mast, through the air and glass of the hull and to the water. I dont remember details about damage to the fiberglass - likely - but the person on the boat suposedly was not seriously harmed.

If the AI/TI had a conductive mast, I think the results would be similar to what happened on the Laser. Strike would favor using the mast, then exit to the nearest water surface using either the bottom of the mast or the metal Ama cross bar.

If the mast is not conductive, its likely similar to just sitting in a kayak. If the strike picks the top of your head.. its not going to be a good day.

FYI, if the mast has carbon fiber, its conductive. If its doesnt, it may not be conductive.. dont know.

However.. have you guys in Florida ever even heard of a kayaker geting struck?


Last edited by walt on Thu Jul 03, 2014 9:46 am, edited 1 time in total.

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PostPosted: Thu Jul 03, 2014 9:44 am 
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Quote:
I have been told that lightning won't strike a sailboat mast.


Im not sure where you heard that but the mast on a sailboat is a good thing as its most likely to take the strike - and this is usually the case. The good thing is that you can for the most part count on it using the mast - rather than the top of your head.


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PostPosted: Thu Jul 03, 2014 9:53 am 
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The AI/TI masts are indeed carbon fiber, so they are conductive.


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PostPosted: Thu Jul 03, 2014 10:00 am 
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Tom Kirkman wrote:
I have been told that lightning won't strike a sailboat mast. While I'd like to believe that, lightning can and does strike carbon fiber fishing rods being held by anglers in boats. So, unless lightning can distinguish between a carbon fiber fishing rod and a carbon fiber sailboat mast, I tend to err on the side of caution.

I once was on a skiff with a fly rod in my hands--about August, 1993--off Flamingo in the Everglades, when I felt sharp little needles in my rod-holding hands. It only took a second or 2 to realize that it was electricity being built up and conducting through the rod to my hands. It scared me at the thought, and I dropped the rod/reel (into the boat), and we left the area. I suspect that I was close to getting a lightning strike. Fisherpersons are regularly hit and killed by lightning in Florida.

Keith

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I sail: Biscayne Bay, Everglades to Cape Romano, Ft Desoto, Cedar Key

"Any intelligent fool can make things bigger and more complex ... It takes a touch of genius and a lot of courage to move in the opposite direction." A. Einstein


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PostPosted: Thu Jul 03, 2014 12:07 pm 
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Another opinion... is is better to leave the mast on or take it off?

If you read internet forums, you will find all sort of posts that having a mast attracts lightning or that if the mast is "grounded" to the water, it will attract lightning. Its my opinion that having a long verticle conductor (like a conductive mast) will influence where lightning strikes but that influence is really not much. This probably depends on the salt content of water but the mast might only change "lightnings mind" about where to strike by a few or few tens of feet. For example, if lightning would have naturally hit some spot on the water but instead you were there with a conductive mast and a few feet away from this spot where lightning would have naturally hit, you may have changed the path of lightnig by a few feet so it uses your mast instead. If the lightning were gong to strike some spot any distance away at all, the strike didnt have your number and with or without the mast, you not going to influence where the strike hits. If the strike does have your number, the conductive mast is better since it will take the strike rather than you. The setup of at least the AI looks to me like its actually very good for getting the charge from the bottom of the mast directly to the water surface.

I also think "grounding" a mast has almost no influence on lightning. Its easy to think it would since to get your boat DC 12 volt lights to go on, they work a lot better with a ground. But ionized air is a very effective conductor and the short distance from the bottom of the mast to the water very easilly gets grounded by ionized air.

Grounding a mast does have some other second order effects related to Corona currents but that model may say that grounding actually reduces your chance of taking a strike (but its not worth worrying about).

If the mast on the Hobie AI or TI is conductive, I would leave it up..


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PostPosted: Fri Jul 04, 2014 6:24 am 
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You have to be skeptical about any advice on lightning as it pretty much can never be proved.. and this applies here also.. but none the less..

I found the link to the story about the laser here http://macgregorsailors.com/forum/viewt ... 10&t=23224

I had most of the story right - except the part about the laser exploding..

Quote:
When I was a teen, I was sailing a regatta in Lasers in Sarasota. There was a storm approaching, but the race committee wasn't cancelling. Finally, people just started heading in quickly. Coach boats were towing sailors in as quickly as possible. A laser is a single person boat, unshrouded. The hull and deck are sealed together airtight making a hollow void. The mast sits down into a tubular step that goes through the deck down to the hull. The lower end of the aluminum mast is separated from the water by a plastic cap and maybe 1/8" of fiberglass.
A girl on our team was in tow, sitting in her cockpit, when lightning struck the top of her laser mast. The electricity went down her mast and then bypassed the plastic cap at the bottom. It went through the air space between the hull and deck, and made a couple of small holes in her hull. Unfortunately, her boat was older, and a little bit leaky. The water in the hull was heated by the electricity and turned to steam. The pressure inside the boat was enough to blow the boat up. The deck blew apart from the hull upward at the bow and stern. Floatation bags flew. Sitting in the middle of the cockpit, the skipper was unharmed, et confused as to why her boat exploded. If she had been touching her boom, however, she may have been hurt.


The picture below is where I think the charge of a lightning strike would be "mostly" disipated to the water surface.


Image


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 Post subject: YES, but not on my TI!
PostPosted: Fri Jul 04, 2014 9:05 am 
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"Lightning won't hit a sailboat mast"...total myth. I was sailing my 32 ft monohull on Lake Superior. At the end of a bad thunderstorm, we were at anchor, when the bolt hit the VHF antenna at the top of the aluminum mast. The light blinded a crew member who just happened to look up at the masthead when the bolt hit. The bolt vaporized 3 feet of the antenna, then traveled down the mast to the chain plate which joins the mast to the iron keel. But the bolt was so powerful that it also jumped to the grounding wire(s) for the boat's electrical system and traveled through the wire conduits burning out essentially all the wired-in equipment! Unknown to us, the current also traveled through the fiberglass hull and exited the gelcoat. The captain of an adjacent anchored boat happened to see the bolt exit through the sides of the hull. He called over that he saw 'fingers' of light traveling outward through the water. I put on a diving mask and dove into the frigid water. There were more than a dozen 'pockmarked' craters in the gelcoat. My crew had sprayed the electronic equipment with a fire extinguisher and then proceeded to check the hull for any holes. We didn't find any water coming in. The strike had taken out the diesel engine, but with a good breeze we were able to sail back to the marina. The boat was immediately lifted out of the water for inspection. It had to be hauled to Duluth for wiring and hull repairs. Luckily, my boat insurance covered most of the $20K repair.
While we were watching the boat being lifted out of the water, an elderly lady walked over to us and asked if I was the owner of the boat. I said yes, she then said I was lucky. Her 40 ft boat had been struck the previous summer, while tied up, and a fist size hole had been punched through the hull below the water line. It sank to the bottom of the marina before any one could react.

I, subsequently, have done quite a bit of reading about boats being struck by lightning. If you are lucky, the current travels down the mast and out through the metal keel without doing much damage. A keel-less boat acts like your car. The current will travel down, where ever it can to find a ground, jumping across gaps to the water. Rubber tires, plastic hulls, etc. will not protect
the hull. The lightning has traveled through thousands of feet of air gap...it won't stop just because there is a foot of rubber between the steel wheels of you car and the pavement, or six inches of plastic hull. For the same reason you don't want to be touching any conducting metal in your car, you don't want to be the 'best' conductor for the lightning on its journey down your mast to
the water. Carbon fiber will conduct current, even over its surface, if the charge is great enough. My nephew got minor electrical burns while fishing in an open boat using a carbon rod, when 'St Elmo's Fire' flashed to his boat.

I try not to be sailing my TI just before, during, or just after a thunderstorm. There really is nothing you can do, if you are out exposed. I have decided that I would have two choices...leave the
sail up and hope that I could sail out of harm's way or drop the mast and try to be the lowest possible lightning 'rod'.


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PostPosted: Fri Jul 04, 2014 11:18 am 
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I have been sailing the Tampa Bay area since 2001. In the summer, we are notorious for afternoon thunderstorms. Therefore, I will tell you to plan your sailing in the morning and be off the water by 2 pm. I race on Thursday evenings and we have been in many of thunderstorms...and I don't like it. Best you can do is 'hope' that you don't get struck...and avoid touching metal. Although I have heard many accounts, fortunately I have not experienced a lightning strike on the water. There are many theories about grounding vs. non-grounding and the height of your mast. I know of folks whose boat was hit by lightning while at the marina slip while a boat with a much bigger mast was right next to them. There is no way of telling. Since the TI mast can be unstepped easily, I would try to sail like hell to get back as soon as possible....if caught (lightning starts), I would lower the mast and peddle back. Just my thoughts.


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PostPosted: Fri Jul 04, 2014 10:05 pm 
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TIDALWAVE wrote:
"Lightning won't hit a sailboat mast"...total myth. I was sailing my 32 ft monohull on Lake Superior. At the end of a bad thunderstorm, we were at anchor, when the bolt hit the VHF antenna at the top of the aluminum mast. The light blinded a crew member who just happened to look up at the masthead when the bolt hit. to the marina. The boat was immediately lifted out of the water for inspection. It had to be hauled to Duluth for wiring and hull repairs. Luckily, my boat insurance covered most of the $20K repair.
.



WOW! That must have been terrifying.....

Was the crew member permanently blinded, or just flash blinded?


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PostPosted: Fri Jul 04, 2014 10:08 pm 
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MikeSail wrote:
I have been sailing the Tampa Bay area since 2001. In the summer, we are notorious for afternoon thunderstorms. Therefore, I will tell you to plan your sailing in the morning and be off the water by 2 pm. I race on Thursday evenings and we have been in many of thunderstorms...and I don't like it.


I was rather hoping it would be a bit safer, cooler and windier a couple of hours after the daily storm......sailing with the sunset is a preferred activity for me, if it's doable.

Do the Tampa storms usually settle in later in the day?


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PostPosted: Sat Jul 05, 2014 4:28 am 
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IMO our best sailing is in fall, winter and spring...when you can sail just about anytime. In summer, you can almost predict the daily weather here: 50% chance of thunderstorms in the afternoon. You do get those days when there is no thunderstorms...and, yes, often the thunderstorms are quick and the sun pops out. I will tell you that sailing in the afternoon in summer is quite exciting here....you can go from 10-12 kts of wind...then comes an approaching cell and the wind goes to 30 kts....30 minutes later it is only 3 kts. Passing thunderstorms usually pack a punch with the wind as they tend to 'suck up' the surrounding air. So, after they pass the wind can drop to near nothing. Don't get me wrong....there is plenty of all year boating in Tampa....you just have to keep a watchful eye in summer.


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