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I was looking for any previous posts about the safety on being aboard the boat on a trailer or on the water and having the mast struck by lightning. Except for the electronics, are we basically safe? What kind of precautions are advised?

If you "Search" lightning strike you will get many relevant hits on this site ... but you will also find that the recommendations are all over the place: this is primarily because things that determine where/when lightning will strike, and what the path of the electrical grounding will be, and what damage will result, are all extremely complex. One might expect that anything as scientific as a lightning strike should follow nice tidy rules - apparently there are many variables.

Brian...it's one of those sailing topics that gets as nasty as politics and religion

Bottom line is there are very few boating fatalities attributed to lightning, and most are in FL if I remember the stats right.

Trying to put an amateur system in is worse than nothing, however .

Catigale wrote:Trying to put an amateur system in is worse than nothing, however .

Ditto. Whether its better to be properly grounded or completely ungrounded is an open question that there hasn't been enough real science or statistics done to solve (and the correct answer may vary from boat to boat) but putting in an amateur path to ground that cannot properly sink the current from a lighting strike is certain to come to grief.

Your best bet is to park your boat near (but not too near) someone with a significantly higher mast

There have been some people who've had lighting strikes on ungrounded boats on this forum, and it has typically come to some blown electronics and very minor repairs.

I did google this after I posted. It was interesting that where I sail in Nebraska, the state has never had an insurance claim for a strike. Growing up I always liked watching the electrical storms there. I probably should worry more about tornadoes.

Number one cause of boat tragedy is loss of steering control.

The lighting thing is just too hard to answer. If your at dock the big question is if your connected to shore power, and then there are 15 different opinions from the experts on how to handle it. You would be amazed how many folks carry around jumper cables on their boat for lighting. (Don't ask, I don't need to give you ideas).

Even Chapman's has their own advice about the "Faraday Cage" and in the near three inch thick latest Chapmans there is all but only three paragraphs on lighting because it's so rare. But really, no one really knows what to do about lighting. When I was a kid and storms would hit on my dads boat and I asked my dad what happens if we get hit by lighting he would just answer: "You die".

Okay.

I used to be slightly leaning towards the isolation camp (ungrounded is better) until my ungrounded boat hanging in the air on a lift got hit about 1.5 years ago. It knocked an inoperative 2 inch thru-hull fitting right out of the boat. If it had been in the water, it would have sunk for sure. Ever since then, I've switched camps and now believe grounding is better (which I will continue to believe unless my grounded boat gets hit) and so always have a set of jumper cables with me to ground the shrouds. With the research I've done since I've been hit, I would say that the grounded camp is a bigger than the ungrounded. Something about an ungrounded mast looking different from a potential perspective than all the other things around it (trees, houses, other boats, etc).

Here's an interesting response, check this out, http://m.sunshinecoastdaily.com.au/news ... t/1204604/ this happened here where I live 2 years ago, it hit a motor boat that was between yacht masts, no yachts were hit. Go figure, excellent video on this link of the actual strike. Make of it what you will, cheers, Dennis.

This may help understanding the process and risks.
As per final comment, unless you know what you are doing this is not a DIY project.

http://www.boatsafe.com/nauticalknowhow/lightning.htm

Stay safe and have fun