Lighting strike

[Rick]

Saturday afternoon while moored at Put in Bay in Western Lake Erie. We were struck by a bolt of lighting in the mast. We have a 2 week old Hunter 38. The charge went down the mast and out of the boat at 5 different spots in the bow above the waterline (all about the size of a 50mm shell hole exiting from the inside out) and possibly more under the waterline (pin holes). It knocked out all electronics. House lights, water pump and bilge pump were ok. Engine would start but not shut down without cutting the fuel line. We were able to make passage back to our home port (26 miles) under engine power. The boat will be surveyed later today after it is pulled. Has anyone had a similar experience and how long was your boat laid up? 60 sailboats in the water all around us and we get hit????? We are in high season and we are itching to get back out there.

 

[Don S/V ILLusion]

sorry to hear about your bad experience Rick

Can't answer your question other than (the obvious) to say it depends on what, if any, other damage the survey finds. Did you or someone else remove the ground strap from mast to keel or was it a side flash which caused the bow damage?

 

[Charlie13958]

Stike

Sorry that you were hit, I have been on a dock at Leamington, and Belle River when other boats were hit. Both those boats were hooked to shore power(well grounded). One of the boats had a bronze thru hull blow out and would have sunk at the dock if it hadn't had two bilge pumps. Did you happen to be using chain to tie to the mooring ball? Lay up time depends solely on the work load at the marina, and the availability of replacement equipment. Possibly your insurance would cover a leased boat during the layup since our seasons are so short.

 

[Rick19334]

Side flash. The boat was just commissioned and the ground strap was check and signed off. We were told by people who say the strike that a "hugh" cloud of black smoke came up from all directions. We didn't see anything as we were picking ourselves off the floor holding our ears (from the shock).

 

[Bill]

Strike

Seven years ago, my boat was struck while moored. Ended up with 40 plus holes from the size of a dime to a quarter around the water line and many hundreds of small pin holes below the water line. Most wiring (including the ground wire) in the boat was vaporized, VHF and other electronics destroyed, flooring literally blown out of place and all things at the top of the mast was obliterated. The repair itself only took around a month. On the other hand, the insurance company's adjuster seemed to think the anyone doing boat repair was crooked by definition and it took nearly three months to get the company to ditch the adjuster (involved some legal threats) and allow the repair to start. All ended well, but lost the whole season. For some reason, there was absolutely no damage to the engine and it's electrical system.

 

[Rick19334]

Thanks for the reply...sounds like very similar damage. The floor is ok but the mast compression pole leaks like a sieve. Were you is with a group of other boats and ask yourself "why my boat?"

 

[Ed Caldwell]

Over a month

We were hit while the boat was unoccupied and at the dock attached to shore power. The strike apparently hit the top of the mast, and exited the boat possibly through the keel, and definitely through the side of the shore power cables that drooped near the water.Damages totaled 12K, thankfully taken care of by BoatUS insurance. No structural damage, just electrical. On the hard for about 3 weeks because we took advantage of the down time to get a bottom job. Dropped the mast as well to replace all the lights and antennas at the top of the mast, all the wiring down the mast, and to add some spreader lights.Get your alternator checked for output, even though the engine started. Our batteries were fried. Carefully go through and checkout all electrical and electronic devices, including all lights. It got into our ground system and went everywhere.What a shame on a brand new boat! Glad no one was hurt.

 

[Gordon Taylor]

Lightning Strike

Sorry to hear about your weekend. We were hit by lightning in our previous boat a few years ago. We thought we were protected by our keel being bonded to the mast and by the "jumper' cables I had hanging off the rigging. We also though that we were protected inside the boat by the mast's "cone" of protection. But we found that there had been a side flash inside the cabin from the keel stepped mast, through some cans of pop in a locker under the berth and out through the hull under the waterline! Turns out fresh water is not a good conductor and damage is much more extensive than in the sea. I have attached a great link for more information on this. You definitely need to have your boat inspected by a good marine surveyor before and after the repairs.

 

[Fred Ficarra7897]

Gordon, in my humble opinion, the good professor doesn't have a clue.

I said IMHO. He did his work for a Grant. And all of his work was based on an assumption. His assumption was that sailboats are grounded so as to direct the strike to the water. Wrong. It's done to prevent the strike in the first place. Ask me how I know.

 

[Steve O.]

question

Not sure what you mean by "Engine would start but not shut down without cutting the fuel line. " Cutting the fuel flow to the engine is how all Yanmars stop. The stop cable operates a mechanical fuel shut-off. If the cable is broken or frozen you can work the lever by hand to stop the engine. You should learn how to do it in case it happens again.

 

[newly anonymous]

good professors...

...don't work for grants. They apply for grants to cover the costs of their research.Ask me how I know.

 

[Scott B]

Ok I'm asking

OK Fred & Newly I'm asking ...... how do you know.Fred, I'm interested in lightning strikes. In the last several weeks we've had severe almost every day, lightning, hail, high winds, heavy rain, so anything I can learn from past experience would be helpful.newly, my wife works at a University and with profs and research grants... just curious.

 

[Rick]

fuel shut off

Not on this model. The fuel shut off solenoid at the engine is electrical controlled from a shut down button next to the engine start switch in the cockpit. We shut the valve at the fuel tank the first time the engine was started. The surveyor informed us of the solenoid valve on our second shut down attempt.

 

[Fred Ficarra7897]

Scott, It's a long story.

I've been looking through the dusty directories of my hard drive for a copy. I guess it's on my old machine that didn't transfer. Drat. Is a condensed version OK? Yes? Cool.Cruising in Costa Rica. Lightening hitting within 50 feet of the boat all rainy season. No problem. Mast grounded to keel.Haul boat. Seal keel with polyurethane to stop rust. Launch. Leave for Panama. Pow! There wasn't any other lightening before or after that hit. Twenty thousand dollars later, the boat's back. No insurance.Why the hit? Long research. The web was just a dream at the time but I had a modem. Even Practical Sailor said it: Grounding the mast prevents the return wave. AKA St. Elmo's Fire. No return path, no strike. I installed a proper ground plate after repairing the 300 holes blown from the keel coating. Haven't had a problem since. That was in '93.

 

[Bob Poff]

Fred, That agrees with...

Your experience agrees with things we do with towers in a TV or Radio station.The idea of trying to conduct the strike is hopeful at best. All you can dois to try and coherce the strike through the path that you set up. It's going where it wants. Sometimes you win. Other times it wins. And its EM field will induce fairly large currents in anything nearby.One school of thought is to keep the tower (or mast) from charging. Years ago on our 800' tower here at work they installed brushes connected to ground. For the heck of it we disconnected the ground lead and measured the current with no storms in the area. If I remember correctly, on a nice day with a breeze we read several amps flowing.Having your mast bonded to the keel, and an electrical path from the keel to the water will work the same way.Where I will agree with the Doctors recomendation is bonding everything together will tend to lessen the damage to electronics, etc. When you do get hit the items bonded together all raise to the same potential. Even if they jump to several thousand volts, they're all the same. And current dosen't flow between them. Yep, I've proven that at an FM radio site with 700' feet of lighting rod (the tower) attached to everything inside the building.Also his comments about jumper cables over the side I would half agree with.Something is better than nothing. But a larger contact area with the water would be even better.While distance helps, it dosen't stop the danger. I remember hearing the spark gaps on my old AM station arcing with the storm still ten to fifteen miles away.Lighting is Mother Natures way of letting you know you ain't in control.

 

[Dan Johnson]

Hey Bob!

One of these days when we cross paths I'll regail you with a story about Channel 49 and some lightening stories about phone system installations.

 

[Bob Poff]

Hey Dan!

Ohhhhh I can picture that.WSOX-FM, previously WGCB-FM was one of my stations.Right across the road from there.We also had the taller tower.I've seen 66 blocks blown all apart down there before I got the place calmed down.