Thunder & lightning

[DanTribe]

Lying in my bunk last night, I started thinking [ bad idea]
We have a large lump of lead hanging down in salt water, and a large aluminium stick pointing to the sky, while lightning flashed all round us. Hard to think of a better conductor!
Why aren't more yachts struck by lightning?
This didn't help me to nod off.

 

[OGITD]

I'm only little ...... so I hide amongst the big-uns .....

 

[SamanthaTabs]

Did you quickly store iPad, laptop and mobile phone in the oven?

 

[Contest1]

Article on the subject in Junes YM, very informative.
Some thing refered to as a diffuser or bottle brush can be fitted to the mast to help avoid lighting strikes.

 

[TradewindSailor]

Superyachts are good to have around with their 130'+ masts .... and also all those antennas on the hills.

I've had a well-grounded yacht with a stainless steel 'brush' atop the mast to help discharge the energy before it became enough cause a strike. I don't believe that it did anything .... but I received no hits.

I now have a catamaran where the mast is isolated and there is no common ground apart from the saildrives. Again no hits.

I've spoken to insurance adjusters that say that there is no obvious protection against strikes ..... evidence : I don't know of any insurers specifying any protection.

I know of boats that have been hit .... but again I haven't got enough information to say what would reduce the likelihood of the hit.

I've sailed through thunderstorms where I was the only boat around ..... and no hits. I suppose there will be a balancing of fate now ...

So perhaps the best thing is to make sure there is something near that is higher than your mast that is more attractive for a discharge/lightning strike ....... Superyacht or coconut palm on top of a hill ...

 

[hartcjhart]

there is in reality little you can do to not get hit, it is at the end of the day down to luck

 

[Gerry]

Been hit twice! Once mid-atlantic, took out both autopilots. Second time a direct hit in Belize, fried the ssb,fore and aft navigation lights(but didn't touch the mast top ones, despite blowing up the vhf aerial). Took out the depth gauge and wind instruments. Scared the bejaysus out of us!

According to research by Florida University 17% of boats are hit EVERY year in that state....
General consensus is that there is little, if anything, you can do to avoid a strike except keep away from storm areas! We always put the laptops and hand held gps and vhf in the oven when there's lightning about, and both times they were all fine.

 

[BrianH]

A friend's boat on the hard in our NE Italian marina sitting in a steel frame was hit this year; his main power switch melted and his anchor winch burned out. He was asleep in the foreward cabin berth just under the winch!

The yacht with mast up was surrounded by as high or higher masts than his and just 20m away was the marina's 30m, substantial, latticed-framed radio mast with full lightening conductor's earthed connectors.

As previous posters have said, there seems little that will prevent a strike if the potential differentials exist, the forces are so vast they can create their own paths regardless of local physicals.

I still worry as I lie at anchor in the local lagoons and one of the many thunderstorms approach - the area is a crucible of violent storms with cold air of the high mountains ringing the warm Adriatic. With my all-chain rode making a good earth connection and mast as the highest point for miles around I seem to be the perfect connector to the approaching dark clouds with flickering lightening arcing down almost continuously. But, it hasn't happened yet ....

 

[DanTribe]

So perhaps the best thing is to make sure there is something near that is higher than your mast that is more attractive for a discharge/lightning strike ....... Superyacht or coconut palm on top of a hill ...[/QUOTE]

Thanks for the advice but superyachts, coconut palms and hills are in short supply on the River Crouch.

 

[Salty John]

Doesn't help to have higher targets near you. We were struck when there were several more attractive looking targets available. Fingers crossed is about as good a protection strategy as any.

 

[macd]

It's worth knowing, should anyone have the misfortune of being hit, that some (better?) insurers routinely leave claims open for six months after the initial strike. It's often the case that some electrical damage will not reveal itself for some time, so this is a means of including such hidden loss in the initial claim.

 

[davidfox]

Lying in my bunk last night, I started thinking [ bad idea]
We have a large lump of lead hanging down in salt water, and a large aluminium stick pointing to the sky, while lightning flashed all round us. Hard to think of a better conductor!
Why aren't more yachts struck by lightning?
This didn't help me to nod off.

Try being in the middle of the North Sea when you have the same thought!

 

[Seajet]

I've been mid-Channel with lightning hitting the water around us, and a nearby ship; I freely admit I was very scared.

When lightning was bad in the Solent one time I suddenly came over all friendly and sailed alongside a Contessa 32 with his bigger mast !

Not that I think it would help, at our moorings once a 20' wooden yawl with wood masts was hit, blowing a plank out of her side; she was surrounded by much taller alloy masts.

I have a chain which I clip onto the chainplates to dangle in the water, shrinksleeved to protect the topsides, but the jury is still out as to whether this would be a conductor or makes the boat more attractive to lightning !

I do fancy one of these masthead diffuser jobs, I've read of them in several articles, supposedly they dissipate ' ion streamers ' which are the prelude to a strike.

Edit; have looked up Force 4, they do these masthead brush style diffusers, but £144.95 is more than I expected !