Lightening?

[greg]

Lightning?

Ok, so now I have this big stick way up in the air, and my next project is to install a new 23' vhf antenna. So that will be two tall sticks way up in the air, one of which wires into the cabin, and one whose base is kinda close to a fuel tank.

Should I be doing anything to protect against lightening or should I just put some c4 at the base of each one and make it a nice painless ending?

I know we are in new england and not Florida, but does anyone put lightening protection on their boats up here?

I'm inclined to just play the lottery, but thought I'd ask.

 

[hntrss]

Man, after 12 years on the tuna grounds and countless squalls, I am convinced that if your number is up , its up. We have had it hit the water 100 feet away. I do turn off the units and breakers if I am anchored, but I don't really sweat it.

 

[MouseTrap]

I thought this thread was going to be about making a boat weigh less :-|

 

[CEShawn]

Funny because I think alot of us think our number is up. I have had two family boats get hit in 20 years, both were at the dock. The second one I had a crew member sleeping and actually wasnt a direct hit but hit the sailboat next to us. On our boat it damaged engine sensors, CAT said it came up through the shaft, not sure how accurate that is. That is just one other thing I do not like about electronic engines.

I have a very good understanding of electrical but lightening seems to be another science in itself.

I do not get the potential bit of it all. Alot of stories I hear people say their antenna's melted, etc. What is funny is I've never seen an antenna get hit myself. What happens when you get those strikes 100' away from you in the open ocean, how is there more potential there than a boat 100' away. Well grounded? LOL...

I have been on ships that have gotten hit my lightening several times. Only a couple times have I seen damage, it was actually to stupid things like wind gauges and then of course radars seem to get hit.

I have heard that green sticks emit alot of static type electricity in storms, anyone experience that yet?

 

[greg]

I thought this thread was going to be about making a boat weigh less :-|

Darn you spell check!

 

[tunamojo]

Nevermind...

 

[Katelyn A]

spell check is for the office......

 

[steveinak]

One of the old timers that fished out of open skiffs told of how his brother was split in half by a lightning strike. They were hiding in the pound net poles and the lightning hit in the water next to the skiff and unfortunately his brother was holding on to the bronze arm of the rudder & killed him on the spot. George also liked to show the stub that used to be his thumb that his brother shot off when they were market hunting !!

 

[F/V First Team]

If you're worried about it, install a grounding plate.

 

[strikecharters]

As one who has been struck by lightning and almost killed while operating an open skiff, I can assure you that it is not a lottery you want to win. I did quite a bit of research after my experience to prevent it from happening to other boats I own and unfortunately it doesn't appear that there is a whole lot you can do to protect yourself from such an occurence. Kind of hard to believe when you hear of airplanes getting hit all the time with no ill effects. Common sense tells you to avoid the situation altogether but kind of tough to do when your 40 miles offshore with a big aluminum tower sticking up in the air. Would love to hear from others with info. on protection.

 

[jerseysportfisher]

There is ways to better protect yourself for lightning strikes on the water, problem is they are not to realistic. Study's have shown that if there are multiple connect points 360' around the boat tied into metal structur that raises (mast or tower), you can essentially create a farrady cage, and will be safe under the cone. The lovely thing with theory is it doesn;t always work that way. Center for lightning research in south FL has proven this to work MOST of the time. My grandfather would ALWAYS disconnect the dyna plate on a throw switch and hangs chains off the outriggers into the water. Problem with the dyna plate is its bronze, has a low melting point and if it doesn't have the surface area to convey the amps it will just blow out from heat. Now you gots a hole in the boat.

 

[starrfish]

its the luck of the draw... my rig used to have a tower and a 23' pulpit.. folded up at the dock, never had a problem. now i have a 23' vhf on a aluminium mast, from the tip to the water is around 35'. 2 summers ago the 19' proline got ruined by lightning, blew all the gauges outa the dash, fried the outboard, actually blew the cover off, the boat was totalled. it was 30 feet away from mine.
i also have a dyna plate. last summer, while at the dock and tied into shore power, a bolt hits a lightpole on the dock during a summer squal about 300' away, that strike affected almost everyone on the dock.. i lost my radar, stereo, sattelite antennas, battery charger, black box that goes to the gps.. other goes with electronic motors ended up buying new brains.. a real mess.
so i guess you can limit your exposure somewhat, but (IMO) lightning goes where it wants, and not much you can do to stop it.
i

 

[greg]

What gets me thinking is the whole carbon fibre thing, and a pole sticking up 30+ feet. Lightning seems to have an affinity for it.

I'm not concerned about damage, just survivability. Getting hit out at the canyons would be a bitch. Guess I'll just keep the sat wx subscription and try to reduce my exposure.

 

[Aloop]

add a little resin and a rolling mat and you got yourself a brand new rod!

What gets me thinking is the whole carbon fibre thing, and a pole sticking up 30+ feet. Lightning seems to have an affinity for it.

I'm not concerned about damage, just survivability. Getting hit out at the canyons would be a bitch. Guess I'll just keep the sat wx subscription and try to reduce my exposure.

 

[MDI45]

Thought the guy shaved his hair and ponytail offLOL.....That is unreal

 

[Keelboater]

Thought I'd revive this thread after reading an article in the latest edition of the Boat US Seaworthy rag. Of course it's just a basic article on the subject. It covers the most traditional method of lightning protection (high mast to grounding plate), but introduces a method for protecting the electronics on board as well as the newer electronic motor controls through use of transient voltage surge suppressors (TVSS). If my boat had a new electronic motor, I might be persuaded to look into these TVSS modules.....especially if I ran offshore on a regular basis. They look like fancy circuit breakers that are actually semi-conductors. They suppress lightning related voltage spikes and have proven themselves in the wind generation and avionics fields where protection of costly electronics is mandatory. Sounds as if for around $200 you can keep that electronic motor running if the "lightning hits the fan", but a bank of these can be installed to protect everything else on board such as expensive electronics and fly by wire controls. That might be the ticket for near by strikes not blowing out all of your expensive toys.

As far as the conventional cone of protection method goes, just as a reminder, the lightning rod IS the highest point above any antennas, and must not be tied into the bonding system of the boat. A separate #4 AWG ground wire must connect it directly to the grounding plate below the water line. The grounding plate must be of sufficient surface area and is suggested to be a minimum of 1 sq. ft. They suggest long narrow ground plates with sharp corners with a thickness of at least 3/16". Adding grooves to it improves conductivity. This is not intended to prevent a strike, but just to safely re-direct it to ground. Now that your boat is on the hard for winter storage, it's a good time to take a look at this.

 

[goin4broke]

Yeah, lightning is truly an unpredictable animal. Wired lots of commercial buildings with lightning protection installed. Talking to some of those guys it truly is a science in it self. Building protection is all about dispersing the energy quickly. There are multiple "bonds" to the steel structure as well as leads to earth from at least 4 corners (depending on building size). This is why cars and planes and steel boats for that matter have greater survive ability. Faraday cage effect.

Homes on the other hand (wood framed) are a different story. It was recommended only for houses with the old aluminum siding have lightning protection. Otherwise your actually attracting lightning without the "aluminum shell" thus causing more damage (house fires). It's not just the energy (electricity) it's the heat that goes along with it.

I have always thought that the worst place for powerboat to be in a lightning storm was next to or worse yet in between two sailboats. The aluminum mast will attract a strike and despite having and solid ground plate in the water it will go where it wants. So if your rig is tied up in proximity to a rag hanger and your tied into marina power it is likely that a strike to the mast could travel down to the water get into your boat through the bonding system and get into the ground wire of your power cord all the way back to the main service ground for the facility potentially wreaking havoc all along the way.

As far as the surge suppressors go I doubt they will do much. But if there willing to warranty losses great. But as I said there's a tremendous amount of heat that goes along with it. If it isn't fried electrically it it probably will be literally.

Unfortunately Greg I don't think there's a perfect solution for being on the water in an area for a likely lighting strike. Maybe Tunaorlater will chime in. As a lineman I'm sure he's seen some crazy s***.

Can't even guess what happened to the fishing rod.

 

[Jangles]

My understanding is that being hit out to sea is quite low. Lightning is looking for the quickest way to ground and wouldn't want to travel through the boat if there is clear water all around. The problem comes when in port, on dock, or on the hard when density of boats and other poor grounds are obstructing a clear path for the lightning. You're best bet when a storm comes is to get the hell away from anything else... don't be the tallest and/or best grounded object in the area.

 

[crabz]

What if you have an all aluminum boat

Luckily lightening storms are very rare in SE Alaska, I have only seen 1 since 1981. Of course I was right in the middle of it on my aluminum boat
None of the fleet got hit, there were lots of fiberglass boats with much taller aluminum masts than me.

 

[Keelboater]

"Lightning is looking for the quickest way to ground and wouldn't want to travel through the boat if there is clear water all around." - Jangles

Jangles - I tend to disagree. The quickest way is through the shortest gap between positive and negative charges that build up. I hear golfers deal with it quite a bit out on a golf course. But those funny looking stick thingies have no place to mount a fishing reel, so why even drag your ass out into a field to swat mosquitoes in the first place?

Crabz - I think a metal hull is good for the faraday cage effect similar to a car or plane strike providing you have a high mast. But I would not want to find out first hand.