Lightning

[Sea-Fever]

Today I took the family out for a run around Portsmouth harbour...more than anything to check everything was OK prior to a longer trip next week.

I always check the wind and tides before i leave port (obviously) and I knew rain was possible with potential for short sunny spells. I admit i didn't pay particular attention to the risk of thunderstorms but found myself smack in the middle of one with lightning to boot. I suddenly felt a bit foolhardy.

I wondered if others pay particular attention to the chance of thunderstorms? Would you stay in port?

The wind was light and the rain, torrential as it was, didn't bother me but I sent the family down below and only half jokingly told the wife she would have to steer if I got fried.

 

[oldharry]

Yes, I think a lot of us feel a bit vulnerable sitting at the bottom of metal mast with lightning around......

 

[Sea-Fever]

I wasn't the only one present....there were a collection of four or five mobile lightning conductors all vying for excessive amperage down the mast. Nobody else looked that bothered but maybe i wasnt close enough to them to discern any panic. I suppose there's not much you can do....you can't get off after all.

 

[mjcoon]

I wasn't the only one present....there were a collection of four or five mobile lightning conductors all vying for excessive amperage down the mast. Nobody else looked that bothered but maybe i wasnt close enough to them to discern any panic. I suppose there's not much you can do....you can't get off after all.

Did you put mobile devices in the cooker?

 

[creeks]

The following is a copy of part of a post on the RNLI Yarmouth Facebook page. Not being on Facebook I can't provide a useable link. Sorry.

Yarmouth RNLI Lifeboat
12 July at 10:52 ·

Yarmouth RNLI rescue yacht struck by lightning
Yarmouth’s Severn class all weather lifeboat (ALB), Eric and Susan Hiscock (Wanderer), was tasked to launch by HM Coastguard on Monday 12 July 2021 at 3.58pm to a 40 ft sailing vessel with electrical failure and a potential engine fire following a lightning strike.
The RNLI volunteer crew arrived on scene west of Newtown Creek and two crew members were put on board the stricken yacht to assess the situation. Although they were very shaken by their experience, all four crew were uninjured. The electrical systems had been destroyed by the strike leaving the engine still running with no means of turning it off. Yarmouth lifeboat crew disabled the engine and checked for hot spots..........

 

[JNKScot]

Yes, I think a lot of us feel a bit vulnerable sitting at the bottom of metal mast with lightning around......

Loop some chain round the mast and put the pick in the water; may or may not help but also may assuage some of your fear.

 

[chrishscorp]

The weather was not what was forecast, we moved from a pontoon to back onto our swinging mooring in Portsmouth hbr and 2 minutes after we cast off we were drenched, but it was the lightening which was the fun bit....... one of the stikes was i guess less than a mile away. All part of the great British summer.

 

[TNLI]

Mr faraday would point out that if a yacht has normal steel rigging the lightning bolt will go down the backstay or forestay, according to which one is straighter, and ends in a good earth. So I would try some chain, no need to tow an anchor clipped to the backstay. Then remove all the antenna and power plugs. If you have plastic cased electronics in a plstic or wooden boat, then you will need to put the critical electronics inside the oven, or metal box. Luckily all my HAM HF gear is old school Kenwood, and they use earthed steel boxes. The radar is not so much of an issue due to internal metal box and the fact that a magnetron valve is not effected by indused votages. The real disater tends to be mast top VHF antennas that are left plugged in, or mast head lights that are left swiched on. Oddly enough a steel or alloy boat, (Mine has an alloy hull, but a composite wood, fiberglass and alloy plated topsides). is far less likely to get struck than a plastic boat, cos the static voltage is the same at the top of the mast as the surrounding sea. Good groundplates help, but many are installed in a way that can result in internal damage due to indirect bonding cable or strap, or simple lack of a sensible backing plate.

 

[lustyd]

I hate to break it to you but all of this was well forecast and the reason we came back to our berth a few days ago in the middle of two weeks holiday.

 

[AntarcticPilot]

I've been out in a thunderstorm once, about 50 odd years ago, in my father's boat. Knowing your mast is the highest thing for miles is pretty scary. If there's a chance of a thunderstorm, I stay at my berth. If it comes up unexpectedly, that's different, but if it's forecast I don't chance it.

 

[capnsensible]

They don't get more comfortable with repetition.....?

They can be relatively common around the Straits of Gibraltar. I personally haven't suffered damage, but seen the effects. It can ruin your day....

 

[RobbieW]

You also dont need a direct hit to fry things, within about 150 metres is close enough as two insurance claims testify (one in Sicily & one in Mallorca)

 

[Juan Twothree]

A fishing vessel got struck a few years ago.

As well as destroying all the electronics and breaking the wheelhouse windows, the lightning bolt blew out a skin fitting, leaving a rather inconvenient hole in the bottom of the boat.

Fortunately, a mallet handle with rag wrapped around it slowed the ingress sufficiently till the lifeboat arrived.

 

[TNLI]

True if the plugs are left in, although I have lightning surge protectors inline with every antenna cable. All those are are small 240v neon tubes that short to earth. Alas you should also fit surge protectors in the supply to the electronics, also normal household units do work.
These are the ones I use for any radio antenna feed and about a tenner each.

 

[Mistroma]

I've been out in a thunderstorm once, about 50 odd years ago, in my father's boat. Knowing your mast is the highest thing for miles is pretty scary. If there's a chance of a thunderstorm, I stay at my berth. If it comes up unexpectedly, that's different, but if it's forecast I don't chance it.

One of my two least favourite things. I still remember lightning all around during the night in the middle of the North sea and about 100nm to nearest land. Only one thing sticking out of the water for miles. Character building and something I always try to avoid.

I wasn't keen on fog either and had 12 hours wandering around in pea-soup closing the Dutch coast. Dead reckoning only and not a single fog horn heard. Urk trawler appeared out of the murk and almost hit us. No sign of anyone aboard, gear out and no response to our horn or VHF. I bought RADAR and DECCA during the winter and thought that would guarantee no fog next year. Nope, pea-soup again in same area (not exactly a surprise). At least I could see all the ships altering course to keep 2nm clear.

 

[Graham376]

Loop some chain round the mast and put the pick in the water; may or may not help but also may assuage some of your fear.

Lightening usually heads for grounded structures so more likely to attract a strike. We've been on board when multiple strikes onto the surrounding salt flats and even a couple into the water between moored boats, which luckily weren't struck. I really don't like it as virtually nowhere aboard to hide from metal - chainplates behind seats, wiring everywhere, mast support post etc.

 

[Laminar Flow]

I experienced a thunder storm off the African coast and at night. At 20m we were the highest thing around. We had a wooden mast and I went about clipping on lengths of cable to the upper shrouds - one of the most uncomfortable things I have done in my life. All around us we could see the lightning strike the sea lighting up the water like some strange form of phosphorescence.

Later, when we were anchored in the roads at Panama there was a thunderstorm every day and every day a yacht was hit. Invariably it would destroy every electronic device on board, whether hooked up or not. One yacht had just received a new and complete shipment of electronics when they were hit. All devices were still in their original packing and all were fried.

 

[TNLI]

Lightening usually heads for grounded structures so more likely to attract a strike. We've been on board when multiple strikes onto the surrounding salt flats and even a couple into the water between moored boats, which luckily weren't struck. I really don't like it as virtually nowhere aboard to hide from metal - chainplates behind seats, wiring everywhere, mast support post etc.

Alas that is not true, it heads for a conductor that has built up to the highest opposite voltage and follows the path of least resistance to it. It also heads towards the nearest point where is can find an isolated conductor. So earthing the mast head to avoid a build up of exccess charge reduces the chances of being struck, that is why you often have near misses. It's only once lightning has struck an object that it looks for a direct path to earth. Most old times like myself store any plastic cased electronics in alloy foil, or metal box.

 

[capnsensible]

I experienced a thunder storm off the African coast and at night. At 20m we were the highest thing around. We had a wooden mast and I went about clipping on lengths of cable to the upper shrouds - one of the most uncomfortable things I have done in my life. All around us we could see the lightning strike the sea lighting up the water like some strange form of phosphorescence.

Later, when we were anchored in the roads at Panama there was a thunderstorm every day and every day a yacht was hit. Invariably it would destroy every electronic device on board, whether hooked up or not. One yacht had just received a new and complete shipment of electronics when they were hit. All devices were still in their original packing and all were fried.

Yeah, all too common around there. Getting replacement stuff shipped is difficult too. Met a chap in Shelter Bay Marina who had taken a big strike and needed to replace every bit of electronics. Had been waiting ages for the new kit to arrive. Not a cheap place to be either....

 

[johnalison]

In fifty years or so, I can't think of an occasion when I have been out at sea in a thunderstorm, though I have endured/enjoyed a number while in harbour. Would I set out when a storm was in prospect? Almost certainly not, though it is only in recent years that forecasts have been that good.