Lightning protection

The NOAA website contains details of lightning deaths. (http://www.lightningsafety.noaa.gov/victims.htm). I extracted boating related deaths as a subset, and placed an asterisk after an entry if it was salt water. My conclusions:

1) Although not indicated, the majority of deaths appear to be in open boats
2) There are enough deaths on salt water for one to take notice. Don't assume you are safer on salt water.
3) Not shown below was that many people since 2006 died from lightning strikes while fishing from jetties, piers, or otherwise on land near fresh or salt water.
4) Dr. Ewen Thompson wrote an excellent 1992 article on lightning and salboats (http://www.kp44.org/LightningAndSailboats.php). It underscores that the safest place to be in a lightning storm is not on one's boat.
5) It may be that a lightning protection system can save lives in boats, but as boatsafe states, "This is not a do-it-yourself project."
6) The myth of the " cone of protection "(http://www.lightningsafety.com/nlsi_pls ... -myth.html) illustrates that simply throwing a grounding plate into the water that is attached to air terminal may not provide adequate protection. This further underscores that a lightning protection system needs to be professionally engineered and installed such that you have achieved, in effect, a Faraday Cage. However, as Dr. Thompson stated, it is no guarantee against damage, albeit it reduces the chances for injury or death.
7) If we do everything we can to avoid a thunderstorm, and are regardless stuck on our boats to ride it out, recommendations offered at (
http://www.nasdonline.org/document/209/ ... ction.html) seem consistent with those offered by Dr. Bob Austin.
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2006. Lake Powell, AZ ( jet ski )
2006. Bob Kidd Lake, AK ( fishing )
2007. Reservoir in Helena, MT ( fishing )
2007. Bowstring Lake, MN (on dock after boating)
2007. West Milford, NJ ( on boat dock after boating )
2008. Choctaw Beach, FL ( fishing boat )*
2008. Lake in Columbia, SC ( jet ski )
2009. Orleans, MA ( shell fishing )*
2009. Soldier Key, FL ( fishing )*
2009. Lake Charles, LA ( fishing )
2010. Stowell, TX (crabbing)*
2010. Bay in Annapolis (jet ski)*
2010. River on Bay Minette, AL (boating)
2011. Warsaw, MO ( pulling out boat at ramp )
2012. Lake Okeechobee, FL ( fishing )
2013. Lake Charles, LA ( fishing )
2013. River in Shelbyville, IL ( fishing )
2012. Lake Okeechobee, FL ( fishing )

* salt water
 
Last summer, a thunderstorm came over us while heading back to port from a whale watch trip. The captain driving the other boat said, "Well, that was exciting."

The boat he was driving has an enclosed helm. The boat I was driving has a tall flybridge with a metal "cage" supporting the canvas and eisenglass. I said, "Fun for you maybe, but I was sitting in a rotisserie!"

We took a lightning hit once in a plane I was flying. Lost all nav and communication equipment, but the engines kept running. Solid IFR. It's a story better told in person. :roll:

As far as the C-Dory goes, it is fast enough that you can get away from weather, if you have the running room. I feel better in our boat than one with a tall "lightning rod", but still try to avoid the situation.

The joke used to be: get next to the sailboat with the tallest mast. Yeah, I don't think so. :shock:
 
I just read a report last week that stated fisherman were the most often struck people by lighting outdoors. One of the reasons was graphite fishing rods. Seems they conduct electricity even better then most metals. Don't forget to pull down you rods out of the racks and place them on the floor.

We have seen many lighting storms in the c-dory when boating in the SJ's but nothing like Texas. I have sat in my house there and watched the man hole covers get popped out of the street in front of the house 4 times. Texas and the high sierras are the only two places I have been where the lighting scares me. I was camping at 8000 ft once when the storm blow in and UP from the valley below us. Its really weird to look down into a lighting storm as it roll's up the side of the mt. you are standing on. For a thankfully short time I was IN the storm. Found a depression on the ground and blended into it. Not fun.
 
The lightning protection for boats is interesting. The Cal 46 we had done a professional dissipators bolted directly to the aluminum mast, which went directly to an aluminum box weldment attatched which was over 8 feet long, and the mast was attatched to a one square foot Dynaplate directly under the mast with 3/4" copper tubing bolted directly to the mast and plate. This is the boat which had at least 3 major lightning strikes with extensive damage each time (no injury). I don't know if the new owner had altered the system.

The boat we took to Europe had 65 foot off the water wooden main mast, with a SS weldment at the very top of the mast--VHF antenna and wind instruments above that. The forestay was directly attached to a cringle iron of SS around the bowsprit, to a bob stay which was attached to the hull at the water line, so part of that plate was in the water all of the time. The upper shrouds went to chain plates which were notched and also had intermediate shrouds attached. We put 3/8" chains into this notch which were in the water anytime we were in a storm. This gave multiple paths for conduction without using the wooden mast (and sail track) One night in Yugoslovia we had over 60 strikes within a mile of our boat in an hour. We had St. Elmo's fire in the rigging a number of times, which meant we were a partial conductor for the lightning. However the only damage we had were several diodes in the wind instruments (which I had replacements for). Of course all antennas and ground connections (often forgotten) were undone. Probably the most frightening time was when another large boat drug into us, and we had to fend him off, and untangle his anchor from our rode--so we were exposed on deck. The rest of the time we were in the "lower salon" much of which was below the waterline.
 
So here's my plan:

Get to shore and in protected space. If not feasible:

Lower the antenna
Remove the cabin top anchor light
Disconnect all electronics
Anchor if possible
Stay in the cabin, low and away from windows and metal

What about the outboard - leave the motor down or tilt the motor up?
 
Lucky Day":3v05m1qd said:
What about the outboard - leave the motor down or tilt the motor up?
Click to expand...

For us at least that would seem irrelevant -- the outboard transom bracket stays in the water regardless of the position of the motor even when the fuel tanks aren't full.
 
Lucky Day":4xfmxens said:
So here's my plan:

Get to shore and in protected space. If not feasible:

Lower the antenna
Remove the cabin top anchor light
Disconnect all electronics
Anchor if possible
Stay in the cabin, low and away from windows and metal

What about the outboard - leave the motor down or tilt the motor up?
Click to expand...

I agree with you completely on the precautions. On the outboard, I'm wrestling with this one. Even though the outboard bracket may always be in the water, the surface area is slight. On the other hand, there is appreciably more surface area exposed to the water when the engine lower unit is down in the water. If lightning struck the cabin, would it jump from the roof to the engine, because it is the most efficient path to ground? Perhaps that would be a good thing instead of jumping through people in the cabin and punching a hole through the floor? Perhaps we don't want to grounded with the lower unit in the water, and that would be safer? The answer to this question is way out of my level of expertise, and it would be nice if anyone with a more intimate knowledge of the subject could give us a definitive answer as to whether the motor should be tilted up in a storm or left in the water.

Rich
 
Leave the outboard down. If you have to crank up and go fast to get out of a dangerous place it is ready to go. If you have damage to the electrics, you might have problem with the tilt and trim....and yet the engine might start.

Be safe.
 
thataway":3dqkw64s said:
Leave the outboard down. If you have to crank up and go fast to get out of a dangerous place it is ready to go. If you have damage to the electrics, you might have problem with the tilt and trim....and yet the engine might start.

Be safe.
Click to expand...

Thanks! That's thinking out of the box. I appreciate your advice.

Rich
 
I wonder if having a thick rubber mat would help if caught off guard in storm. Tractor supply sells them or the type they sell for truck beds. After lowering antenna and other safety ideas would crouching on a rubber mat during storm isolate you?
 
Larry Patrick":2vs8s783 said:
I wonder if having a thick rubber mat would help if caught off guard in storm. Tractor supply sells them or the type they sell for truck beds. After lowering antenna and other safety ideas would crouching on a rubber mat during storm isolate you?
Click to expand...

It won't help at all. Lightning will punch through just about anything if it is the shortest path to ground to include people, a rubber mat, the floor of your boat, and even several inches of concrete. The key is to stay low in the boat and away from metal. You don't want to be the highest point on your boat. That's why open boats are so dangerous. But what is also dangerous is for a person to be centered directly under the antenna or radar dome that's attached to the roof of one's boat. Lightning deaths have occured, for example, in sailboats whose masts don't got through to the keel when people are positioned directly underneath between the mast and the hull.

Let's put things in perspective. The NOAA states: "On the Water: The vast majority of lightning injuries and deaths on boats occur on small boats with NO cabin. It is crucial to listen to weather information when you are boating. If thunderstorms are forecast, do not go out. If you are out and cannot get back to land and safety, drop anchor and get as low as possible. Large boats with cabins, especially those with lightning protection systems properly installed, or metal marine vessels are relatively safe. Remember to stay inside the cabin and away from any metal surfaces. Stay off the radio unless it is an emergency!"(http://www.lightningsafety.noaa.gov/outdoors.htm)

I think you can see from the comments that most of us have a healthy respect for lightning, and that is a good thing, because that respect instills in us a desire to take prudent preventive actions that will help to minimize its risks.

Rich
 
Good comments - I like Rich's summary.

I would underline his word prevention. WeatherTap.com is a great app for prevention - it shows the location of any cells and storms- and gives data on intensity, arrows depicting predicted movement, and probability of rotation into possible tornado.

We used it on the boat, when camping or hiking, and in everyday life ( yesterday it cancelled our picnic with Grandkids, and it was fortunate - lightning WAS intense as predicted).

Most storms (or conditions leading to probability) ARE predicted by NOAA - in our experience, most of those who think otherwise are simply unaware. The old admonition - BE PRUDENT! - think ahead, watch the forecasts - sure, be a coward.

We have cruised almost 40,000 miles of coastal and lake waters and rarely had problems with lightning - although we spent many an afternoon sipping tea or beer in a marina pub watching the flashes out the window (and that was NO problem)..
 
Another tip I have read (if you're doing the hunkered down maneuver) is to keep your feet close together and only have them touch the ground. i.e. hunker down but don't spread out. IIRC this reduces any voltage difference (which varies by distance from strike) and so can reduce ill effects.

Here is reference to it in a quote from a New York State lightning safety page, and the link to the whole page below it:

Crouch down on the balls of your feet with your feet close together. Keep your hands on your knees and lower your head. Get as low as possible without touching your hands or knees to the ground. DO NOT LIE DOWN!

They mention on the page that if you are in a boat and cannot get to shore to go below ("below" on our boats) and crouch down.

http://www.health.ny.gov/environmental/ ... lightning/
 
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