The actual odds of being hit by lightning

[walt]

(two parts since only three images per post)

At 8:14, an example protection wire and equipment is shown. The protected area is under the red.. very clear. Anything outside the red is not protected. In that example, there is a portion of some equipement on the right side that is outside of the protected red area.



The next two pictures are at 8:27 and 8:54





What is said on the video in this section is that the area under the green is protected by the wire but that the piece of equipement shown by the red can be reached by a step leader instead of the protection wire. The red piece is outside (the green protection area) and is potentially subject to a direct lightning strike.

Now go back to the picture you posted in the section where the guy is leading into the discussion of how things work "asking what about". Your conclusion that things inside the sphere wont get struck is inconsistent with everything in the discussion area.

And how this relates to anything ungrounded is just not at all in that video (unless you look at that picture and don’t see a ground symbol on the lines drawn )

[Hamin' X]

Nice job of cherry picking with that last picture, Walt. If you rewind just before it, they show and demonstrate that the strike current of the strike that hit the bus was of a specific magnitude, such that it could not reach the grounded mast/wire, or reach the ground. But it was of sufficient magnitude to reach the buss. If the current had been less, it would not have reached the buss; if more, it would have gone to the mast, or to ground. I don't know if you are purposely misleading the forum, or if you really don't understand.

~Rich

[walt]

I don't know if you are purposely misleading the forum, or if you really don't understand.

Sorry Rich.. a lot has been discussed and the video there for anyone to view. It would be pretty obnoxious to carry this on more.

I got the answer I needed about what your backup is for these, I think a lot of others must have also.

IF YOU ARE NOT GROUNDED, YOUR HAVE NOTHING TO WORRY ABOUT.
If you use dissipators, DO NOT GROUND; you will only be making yourself more attractive to lightning.

[Dimitri-2000X-Tampa]

Well, I just had to pull this post out of its almost 10 year old grave....why....CAUSE I GOT HIT AGAIN!!! So, guess what, most everything in this thread is kind of BS cause in Sept 2018, my macX got hit a second time by lightning and this time it was grounded, so the only thing to learn is that lightning is dangerous and does what it feels like. Take that Mr. probability!

What was different 6 years after the first time I got hit? Well, this time I actually saw it within a few seconds of the blast. I'm in my living room and I hear the very big boom, and immediately was able to look at my boat and the top of the mast was glowing and smoking for a couple more seconds. In 2012, I had to do some deduction to figure out I got hit by lightning (and I still have the shroud spar with about a 3/8 inch hole burned through it). Unfortunately the half melted lightning diffuser I once had fell off while trailering so I don't have that anymore and it was not on the mast when it got hit the second time. The other big difference if you followed all my posts in this old thread is that I started grounding better after my first strike and still got hit again...maybe not as well grounded as Rich was saying (just two old shrouds cut in half and pinned to the real shrouds and dangled in the water) but grounded none the less. The one good thing was there was less damage the second time when it was grounded.

The bottom line is I was hit once ungrounded with lightning diffuser, and once grounded with no lightning diffuser.

So, I'm pretty freaked out now about leaving the boat on the lift with mast up, and unless I'm actively using it a fair amount, I may keep the mast down all the way or in the crutch position at least. I have the mast up now for about a month and by May when the bigger stormy season starts, I'll probably put it back on the trailer since I want to change the gear oil anyways.

[Russ]

You need to buy a lottery ticket.

You do live in lightning alley so there is that.

Interesting that the diffuser did nothing to prevent a strike. I've been tempted to buy one. Now I think not.
Grounding seems to be a difficult thing to do. I guess your grounding wires gave it a path rather than through the bottom of the boat.

Besides a glowing and smoking mast, what damage did the second strike do.

[Dimitri-2000X-Tampa]

Yes, I think the wires from the shrouds into the water did give it a path around the sides which did cause less damage. For example, on the first strike, both the lift motors got fried (one right away and another one that failed a few months later) and that was a real pain to fix. They didn't work right after the second strike either, but I think I was able to just replace some GFCI's and they came back. They are still running ok after the second strike but one has been a bit flaky and I redid the connections and it seems ok now. I had also put in a sub electric panel and extra grounding spike near the dock after the first strike, so that could have helped too.

I happen to have the list of things I replaced on the boat after the second strike:

Of course the obvious stuff...Windex, post and spike gone
Antenna gone
Anchor light gone

Signs of impact in boat
Left panel damaged Cabin lights kinda work
Water pump works
Fm radio gone
Amazingly vhf radio comes on but is probably damaged since doesn t turn off
Tv probably gone

Anchor light switch seized up

$14.98

Both electrical panels are damaged:

https://www.westmarine.com/buy/west-mar ... ecordNum=2
Model # 11861531 | Mfg # 8930 | UPC # 25282108794
$44.99
Model # 11861556 | Mfg # 8931 | UPC # 25282108817
$64.99

5amp fuse for autopilot
$7.99

LED Cabin bulb
$12.99

Nicro air ventilator fan burned out (not sure if this might have been going anyway)
3 inch
$180.88

Forward (red/green) nav lights do not work and had to be replaced

Batteries were replaced too.

The connector to the FM Stereo/CD player was melted and the unit had to be replaced, probably the helm remote control too...don't remember the price. The stereo is mounted on the cabin top right behind the head so it is very close to the shroud attachment point.

The Auto Pilot was disconnected so it wasn't damaged

I tend to leave VHF disconnected from the masthead antenna now unless I need it, I think I still had to have that repaired by standard horizon though...just too close to the bolt

I also did have a flukey outboard electrical problem that required me to replace the electronic ignition module, but now I can't remember when that was...and it was not directly linked to a strike, but it may have degraded later due to a strike too...cause those things are usually pretty reliable.

So basically a lot of electrical stuff...even though insurance gave me money both times, its still a big time sucking setback to get everything fixed so now I'm not leaving it mast-up all the time, just for a few months now and then I'll put it back on the trailer, maybe go on a cruise in May with it some place further away.

This is the third time overall that my property has been hit (since 1995) ...in the lightning capital of the world..lol Twice to the boat but there is also always stuff damaged in the house too, like TV's, switches, garage door openers, ice makers...etc. Lots of stuff gets affected by the surge.

[PhysicsTeacher]

This is a pretty informative talk about cruising and lightning by a retired electrical engineer:

[NiceAft]

I started reading these latest postings on this thread, and then stopped. The fact of the matter is nothing works; nothing includes grounding to the water, diffusers, etc. Nothing

Lightning is so powerful it overloads everything you can put up to redirect it. It goes where it wants.

Check the weather. Stay away from it, and if you can’t…..pray. I can’t say that that will work, but it can calm your nerves. I have had the misfortune of sailing through a lightning storm while sailing a Sunfish type craft on a small N.Y. lake. It came from behind mountains and trees. I can’t say enough how scary that was. I don’t wish to be in that situation again.

[Russ]

Wow....it seems like anything connected got fried.

I recently experienced a home lightning strike. Killed a bunch of things and popped every GFI.

Don't mess with lightning

[Hamin' X]

But what triggered my latest rant is the statement about these diffusers and how you shouldn't ground when you use them...well, I ACTUALLY had my boat hit by lightning while using one of those (very goofy looking) diffusers and not being grounded with my boat up on a lift. So, you can rant and rave about all this high brow theory which ever way you want, but there is no doubt that I have personal empirical evidence that my boat was hit when it was isolated and using a diffuser. So, until I get hit again, with my little shroud wires dangling into the water, I have now done a 180 and due to my strike, now pay more attention to people like my mechanic who can come up with a plausible theory about why my boat got hit when it was isolated...and consequently, I'm in the grounding camp now.

As I said a long time ago, "nothing will give you 100% protection". Sorry for your misfortune. Perhaps if you still had a disipator, or a completely bonded ground system, you could have avoided this. In the end, this is why we buy insurance, or take the risk ourselves.

We had a properly protected substation destroyed locally last year. No 100% guarantees.

[Dimitri-2000X-Tampa]

Can't say I can buy into the dissipater theory either seeing I had one and it got melted by a lightning bolt. I watched the video that physicsteacher posted and most of it it seemed pretty reasonable, until he started going on and on about the dissipater and then with a smirk said he had a melted one too! I think its a gimmick. The full grounding could certainly help and most 'alwaysinthewater' sailboats have that but my problem is the boat lift, which not only raises the boat higher but also makes it harder to ground, just two wires dangling in the water off the shrouds is not the same amount of 'contact' as these keelboats that have much more ground contact (not just the big plates at the water line, but prop shaft, keel, etc.). But yea, no total protection for anything. Saw a video with a woman who was struck and killed on a beach in Mexico, plenty of taller things around but the bolt hit her anyway. There was a 15yo kid on a jetski who got hit in Davis Island basin a few years back but lived due to the quick thinking of a bystander who saved him (floating unconscious in the water). At least thats one good thing about sailboats, they may get hit a lot but the people are usually fairly safer because of the cone effect that sends the charge around them instead of thru them. Open powerboats for example get hit a lot less often, but when they do, the people are in more danger. Anyway, I don't hang out on my boat during a thunderstorm when its on the lift....its terrifying enough being 80 feet away inside the house.

My comments from all those years ago after the first strike are kind of funny now though...

[Russ]

Dimitri, it sounds like you have done quite a bit to protect for lightning as best you can. Living in lightning alley it is expected.

Do you have one of those Whole House Surge Protectors? I would imagine it's almost code in Florida.

[Starscream]

I happen to have the list of things I replaced on the boat after the second strike:

But no hull damage, correct? That's a big relief, suggesting that there's a way for the electricity to get out of the Mac without having to melt a hole in the fiberglass.

I wonder how a person would have fared if they had been on your boat at the time of the strike(s).

[Dimitri-2000X-Tampa]

@Russ, there is a very simplistic ceramic thing on the main panel from the street that is designed to blow up if there is a direct hit to that line, but the 3 times I got hit it was in the backyard and only caused a surge and not blew out the lightning arrestor.

But no hull damage, correct? That's a big relief, suggesting that there's a way for the electricity to get out of the Mac without having to melt a hole in the fiberglass.

I wonder how a person would have fared if they had been on your boat at the time of the strike(s).

Yes, thats right. On the first strike, it did pop out a 2inch brass thruhull that used to be used for a depth sounder, I had that fiberglassed in and on the second strike there was no effect on the hull.

A person certainly would have been pretty terrified, thats about as far as I can fathom.. In my younger days, I was very close to a couple of bolts, like running on the beach once in Sarasota after windsurfing and a storm cropped up from inland and struck a pole about 10 feet from me and two other guys who were trying to run to shelter. Even though the bolt didn't hit us directly, the shock wave knocked all 3 of us down and I do recall feeling some voltage in my lower legs..like from my bare feet (running in wet sand) to my knees..thats just the electricity going thru the sand to ground and its enough to feel even if the path isn't 'thru' you which of course, is much worse.

[sunshinecoasting]

How many times do you have to get hit to realise that grounding is what's causing it, DO NOT ground your mast under any circumstances.