sailboats and lightning

Yachting Monthly

• Digital edition

Sailing in lightning: how to keep your yacht safe

• In partnership with Katy Stickland
• July 22, 2022

How much of a concern is a lightning strike to a yacht and what can we do about it? Nigel Calder looks at what makes a full ‘belt and braces’ lightning protection system

Storm clouds gather at Cowes, but what lightning protection system, if any, does your boat have for anchoring or sailing in lightning? Credit: Patrick Eden/Alamy Stock Photo

Most sailors worry about sailing in lightning to some extent, writes Nigel Calder .

After all, going around with a tall metal pole on a flat sea when storm clouds threaten doesn’t seem like the best idea to most of us.

In reality, thunder storms need plenty of energy, driven by the sun, and are much less frequent in northern Europe than in the tropics.

However, high currents passing through resistive conductors generate heat.

Small diameter conductors melt; wooden masts explode; and air gaps that are bridged by an arc start fires.

Sailing in lightning: Lightning is 10 times more likely over land than sea, as the land heats up more than water, providing the stronger convection currents needed to create a charge. Credit: BAE Inc/Alamy Stock Photo

On boats, radio antennas may be vaporised, and metal thru-hulls blown out of the hull, or the surrounding fiberglass melted, with areas of gelcoat blown off.

Wherever you sail, lightning needs to be taken seriously.

Understanding how lightning works, will help you evaluate the risks and make an informed decision about the level of protection you want on your boat and what precautions to take.

Most lightning is what’s called negative lightning, between the lower levels of clouds and the earth. Intermittent pre-discharges occur, ionising the air.

Whereas air is normally a poor electrical conductor, ionised air is an excellent conductor.

These pre-discharges (stepped leaders) are countered by a so-called attachment spark (streamer), which emanates from pointed objects (towers, masts, or lightning rods) that stand out from their surroundings due to their height.

Summer is the season for lightning storms in the UK. Here, one finds early at Instow, Devon. Credit: Terry Matthews/Alamy Stock Photo

This process continues until an attachment spark connects with a stepped leader, creating a lightning channel of ionised air molecules from the cloud to ground.

The main discharge, typically a series of discharges, now takes place through the lightning channel.

Negative lightning bolts are 1 to 2km (0.6 to 1.2 miles) long and have an average current of 20,000A.

Positive lightning bolts are much rarer and they can have currents of up to 300,000A.

Preventing damage when sailing in lightning

A lightning protection system (LPS) is designed to divert lightning energy to ground (in this case the sea), in such a way that no damage occurs to the boat or to people.

Ideally, this also includes protecting a boat’s electrical and electronic systems, but marine electronics are sensitive and this level of protection is hard to achieve.

Lightning protection systems have two key components: First, a mechanism to provide a path with as little resistance as possible that conducts a lightning strike to the water.

This is established with a substantial conductor from an air-terminal to the water.

Components of an external and internal lightning protection system. Credit: Maxine Heath

This part of the LPS is sometimes called external lightning protection.

Second, a mechanism to prevent the development of high voltages on, and voltage differences between, conductive objects on the boat.

This is achieved by connecting all major metal objects on and below deck to the water by an equipotential bonding system.

Without this bonding system high enough voltage differences can arise on a boat to develop dangerous side flashes.

The bonding system can be thought of as internal lightning protection.

Rolling ball concept

Lightning standards, which apply ashore and afloat, define five lightning protection ‘classes’, ranging from Class V (no protection) to Class I.

There are two core parameters: the maximum current the system must be able to withstand, which determines the sizing of various components in the system, and the arrangement and number of the air terminals, aka lightning rods.

Let’s look at the arrangement of the air terminals first. It is best explained by the rolling ball concept.

A lightning strike is initiated by the stepped leaders and attachment sparks connecting to form the lightning channel.

The distance between the stepped leader and the attachment sparks is known as the breakdown distance or striking distance.

If we imagine a ball with a radius equal to the striking distance, and we roll this ball around an object to be protected, the upper points of contact define the possible lightning impact points that need to be protected by air terminals.

Lightning protection theories and classifications rely on a ‘rolling ball’ concept to define requirements, areas of risk and protected areas. Credit: Maxine Heath

The air terminal will theoretically provide a zone of protection from the point at which the terminal connects with the circumference of the rolling ball down to the point at which that circumference touches the water.

The shorter the striking distance, the less the radius of the rolling ball and the smaller the area within the protection zone defined by the circumference of the rolling ball.

The smaller the protection zone, the more air terminals we need. So, we use the shortest striking distance to determine the minimum number and location of air terminals.

Class I protection assumes a rolling ball radius of 20m; Class II assumes a rolling ball radius of 30m.

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Boat building standards are based on a striking distance/rolling ball radius of 30m (Class II).

For masts up to 30m above the waterline, the circumference of the ball from the point at which it contacts the top of the mast down to the water will define the zone of protection.

For masts higher than 30m above the waterline, the ball will contact the mast at 30m and this will define the limit of the zone of protection.

If Class I protection is wanted, the radius of the ball is reduced to 20m, which significantly reduces the zone of protection and, on many larger recreational boats, may theoretically necessitate more than one air terminal.

Protection classes

With most single-masted monohull yachts, an air terminal at the top of the mast is sufficient to protect the entire boat to Class I standards.

The circumference of the rolling ball from the tip of the mast down to the surface of the water does not intercept any part of the hull or rig.

However, someone standing on the fore or aft deck might have the upper part of their body contact the rolling ball, which tells us this is no place to be in a lightning storm.

Some boats have relatively high equipment or platforms over and behind the cockpit.

Protection classes to protect your boat while anchored or sailing in lightning

These fittings and structures may or may not be outside the circumference of the rolling ball.

Once again, this tells us to avoid contact with these structures during a lightning storm.

Ketch, yawl, and schooner rigged boats generally require air terminals on all masts, except when the mizzen is significantly shorter than the main mast.

The external LPS

The external LPS consists of the air terminal, a down conductor, and an earthing system – a lightning grounding terminal.

The down conductor is also known as a primary lightning protection conductor.

All components must be sized to carry the highest lightning peak current corresponding to the protection class chosen.

In particular, the material and cross-sectional area of the air terminal and down conductor must be such that the lightning current does not cause excessive heating.

The air terminal needs to extend a minimum of 150mm above the mast to which it is attached.

A graph depicting NASA’s record of yearly global lightning events. The Congo once recorded more than 450 strikes per km2

It can be a minimum 10mm diameter copper rod, or 13mm diameter aluminum solid rod.

It should have a rounded, rather than a pointed, top end.

VHF antennas are commonly destroyed in a lightning strike.

If an antenna is hit and is not protected by a lightning arrestor at its base, the lightning may enter the boat via the antenna’s coax cable.

A lightning arrestor is inserted in the line between the coax cable and the base of the antenna.

It has a substantial connection to the boat’s grounding system, which, on an aluminum mast, is created by its connection to the mast.

In normal circumstances, the lightning arrestor is nonconductive to ground.

When hit by very high voltages it shorts to ground, in theory causing a lightning strike to bypass the coax – although the effectiveness of such devices is a matter of some dispute.

Down conductors

A down conductor is the electrically conductive connection between an air terminal and the grounding terminal.

For many years, this conductor was required to have a resistance no more than that of a 16mm² copper conductor, but following further research, the down conductor is now required to have a resistance not greater than that of a 20mm² copper conductor.

For Class I protection, 25mm² is needed. This is to minimise heating effects.

Let’s say instead we use a copper conductor with a cross-sectional area of 16mm² and it is hit by a lightning strike with a peak current corresponding to Protection Class IV.

Sailing in lightning: This catamaran relies upon cabling to ground from the shrouds but stainless steel wire is not a good enough conductor. Credit: Wietze van der Laan

The conductor will experience a temperature increase of 56°C. A 16mm² conductor made of stainless steel (for example, rigging ) will reach well over 1,000°C and melt or evaporate.

Shrouds and stays on sailboats should be connected into a LPS only to prevent side flashes.

The cross-sectional area of the metal in aluminum masts on even small sailboats is such that it provides a low enough resistance path to be the down conductor.

Whether deck- or keel-mounted, the mast will require a low resistance path, equivalent to a 25mm² copper conductor, from the base of the mast to the grounding terminal.

Grounding terminal

Metal hulled boats can use the hull as the grounding terminal. All other boats need an adequate mass of underwater metal.

In salt water this needs a minimum area of 0.1m². In fresh water, European standards call for the grounding terminal to be up to 0.25m².

A grounding terminal must be submerged under all operating conditions.

An external lead or iron keel on monohull sailing boats can serve as a grounding terminal.

This owner of this Florida-based yacht decided to keep the keel out of the equation when is came to a grounding plate. High electrical currents don’t like sharp corners, so a grounding plate directly beneath the mast makes for an easier route to ground. Credit: Malcolm Morgan

In the absence of a keel , the cumulative surface area of various underwater components – propellers, metal thru-hulls, rudders – is often more than sufficient to meet the area requirements for a grounding terminal.

However, these can only be considered adequate if they are situated below the air terminal and down conductor and individually have the requisite surface area.

Metal through-hulls do not meet this requirement.

If underwater hardware, such as a keel, is adequate to be used as the grounding terminal, the interconnecting conductor is part of the primary down conductor system and needs to be sized accordingly at 25mm².

Propellers and radio ground plates

Regardless of its size, a propeller is not suitable as a grounding terminal for two reasons.

First, it is very difficult to make the necessary low-resistance electrical connection to the propeller shaft, and second, the primary conductor now runs horizontally through the boat.

The risk of side flashes within the boat, and through the hull to the water is increased.

Sailing in lightning: GRP hull, fairing filler and iron keel will have carried different voltages during the strike – hence this damage

An engine should never be included in the main (primary) conducting path to a grounding terminal.

On modern engines, sensitive electronic controls will be destroyed in a lightning strike, and on all engines, oil in bearings and between gears will create resistance and therefore considerable heat which is likely to result in internal damage.

However, as it is a large conductive object, the engine should be connected to the internal lightning protection system.

Internal lightning protection

On its way to ground, lightning causes considerable voltage differences in adjacent objects – up to hundreds of thousands of volts.

This applies to boats with a functioning external lightning protection system but without internal protection.

Although the lightning has been given a path to ground along which it will cause as little damage as possible, dangerous voltages can be generated elsewhere, resulting in arcing and side flashes, threatening the boat and crew, and destroying electronic equipment.

We prevent these damaging voltage differences from arising by connecting all substantial metal objects on the boat to a common grounding point.

One of the holy grails of marine photography – a direct lightning strike on a yacht’s mast. Credit: Apex

The grounding terminal is also wired to the common grounding point.

By tying all these circuits and objects together we hold them at a common voltage, preventing the build-up of voltage differences between them.

All conductive surfaces that might be touched at the same time, such as a backstay and a steering wheel, need to be held to the same voltage.

If the voltages are the same, there will be no arcing and no side flashes.

The bonding conductors in this internal LPS need to be stranded copper with a minimum size of 16mm².

Note that there can be bonding of the same object for corrosion prevention, lightning protection, and sometimes DC grounding.

We do not need three separate conductors.

Electronic Device Protection

With lightning protection systems, we need to distinguish electric circuit and people protection from device protection.

Even with an internal LPS, high induced voltages may occur on ungrounded conductors (such as DC positive) which will destroy any attached electronics.

A mechanism is needed to short high transient voltages to ground.

This is done with surge protection devices (SPD), also known as transient voltage surge suppressors (TVSS) or lightning arrestors.

Marine-specific SPDs are few in number and domestic models are not suitable for boats

In normal circumstances these devices are non-conductive, but if a specified voltage – the clamping voltage – is exceeded they divert the spike to ground.

There are levels of protection defined in various standards depending on the voltages and currents that can be handled, the speed with which this occurs, and other factors.

This is a highly technical subject for which it is advisable to seek professional support.

Most SPDs are designed for AC circuits.

When it comes to DC circuits there are far fewer choices available to boat owners although there are an increasing number for solar installations that may be appropriate.

There is no such thing as a lightning-proof boat, only a lightning-protected boat, and for this there needs to be a properly installed LPS.

Nigel Calder is a lifelong sailor and author of Boatowner’s Mechanical and Electrical Manual. He is involved in setting standards for leisure boats in the USA

Even so, in a major strike the forces involved are so colossal that no practical measures can be guaranteed to protect sensitive electronic equipment.

For this, protection can be provided with specialised surge protection devices (SPDs).

The chances of a direct lightning strike on a yacht are very small, and the further we are north or south of the equator, the smaller this chance becomes.

It’s likely your chances of receiving a direct lightning strike are very much higher on a golf course than at sea.

‘Bottle brush’-type lightning dissipators are claimed by sellers to make a boat invisible to lightning by bleeding off static electrical charge as it builds up.

The theory rests upon the concept that charged electrons from the surface of the earth can be made to congregate on a metal point, where the physical constraints caused by the geometry of the point will result in electrons being pushed off into the surrounding atmosphere via a ‘lightning dissipator’ that has not just one point, but many points.

It is worth noting that the concept has met with a storm of derision from many leading academics who have argued that the magnitude of the charge that can be dissipated by such a device is insignificant compared to that of both a cloud and individual lightning strikes.

It seems that the viable choices for lightning protection remain the LPS detailed above, your boatbuilder’s chosen system (if any), or taking one’s chances with nothing and the (reasonable) confidence that it’s possible to sail many times round the world with no protection and suffer no direct strikes.

Whichever way you go, it pays to stay off the golf course!

Enjoyed reading Sailing in lightning: how to keep your yacht safe?

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What to do in a Lightning Storm on a Boat

• By Mike Telleria
• Updated: February 10, 2020

Powerful, dangerous, highly unpredictable — all are common descriptions of lightning storms. A direct strike that results only in ringing ears and a few roasted electronics would be considered lucky. Unlucky would be through-hulls blown out, a sunk boat or worse — possibly serious injury or death.

Many powerboaters like to think that they’ve got the speed to simply outrun or get out of the way of lightning storms , or they figure they’re safe if they go boating only when it’s clear and sunny. That’s an attitude aided by the low odds of a boat being struck by lightning, which BoatU.S. pegs at about one out of 1,000 boats in any given year.

No worries, right, mate? Wrong.

Engines can malfunction ; big lightning storms can leave no room to escape; sunny mornings can turn into dark, threatening afternoons. If yours is the only boat in the area during a lightning storm, the odds of being struck go way up, leaving you and your crew vulnerable to millions of volts raining down from the skies. Lightning and boats do not mix. While manufacturers can build in a degree of protection, lightning protection begins with boaters being informed and prepared to act in the event of a thunderstorm or actual strike. You should know the following techniques and strategies.

Boating in a Thunderstorm is Bound to Happen at Some Point

A strategy of boating only on sunny, cloudless days may work well in places like Idaho and California, but that would mean almost never using the boat in places such as Florida, Louisiana and much of the Midwest. For example, most of Florida — the Sunshine State — has at least 70 to 80 thunderstorm days per year, with some parts having more than 100 thunderstorm days per year (with increased activity during the summer months).

Absolutely, boaters should track VHF , Internet and television weather reports and make responsible decisions about whether to go boating depending on the likelihood of lightning storms. Short-term forecasts can actually be fairly good at predicting bigger storms, but small, localized storms might not be reported. This is when knowing how to read the weather yourself can come in handy. (The U.S. Power Squadrons offers great weather courses for boaters, and there are many books that cover the basics.)

Lightning strikes typically occur in the afternoon. (Florida estimates 70 percent occur between noon and 6 p.m.) A towering buildup of puffy, cotton-white clouds that rise to the customary flat “anvil” top is a good indication to clear the water and seek shelter — or move out of the storm’s path if possible. That’s if the storm is at least somewhat off in the distance (most storms are about 15 miles in diameter and can build to dangerous levels in fewer than 30 minutes). If lightning and thunder are present, just count the seconds between the lightning and corresponding thunder and then divide by 5 — this will provide a rough estimate of how many miles away the storm is.

A storm that builds directly overhead might be less obvious until those pretty white clouds that were providing some nice shade moments ago turn a threatening hue of gray as rain dumps on you and the wind starts to howl or, worse yet, boom with thunder and lightning that are right on top of each other. Now is the time for a mad dash to the dock and shelter if close by. Like the National Weather Service says: “When thunder roars, go indoors!” You really don’t want to be on a boat struck by lightning. If out on open water or too far from shore and shelter, it’s time to hunker down and ride it out.

Caught in Thunderstorm on a Boat

Boaters who have been struck by lightning often begin their stories with “I was caught in this storm … ” before they share their miraculous or harrowing tales of survival and destruction (BoatU.S. has a number of first-person storm stories archived online: boatus.com/seaworthy/swthunder). Even though getting caught in a storm is not always avoidable, there’s still plenty that boaters can do to minimize the chance of a strike and lessen injury and damage if there is a strike.

How to Stay Safest in a Thunderstorm

We all learn in grade school that it is not safe to be outside during a lightning storm. We also learned that lightning seeks the highest point, and on the water that’s the top of the boat — typically a mast, antenna, Bimini top, fishing rod in a vertical rod holder or even the tallest person in an open boat. If possible, find a protected area out of the wind and drop anchor . If the boat has an enclosed cabin, people should be directed to go inside and stay well away from metal objects, electrical outlets and appliances (it’s a good idea to don life jackets too). Side flashes can jump from metal objects to other objects — even bodies — as they seek a path to water.

A Microwave Oven is a Faraday Cage

Lowering antennas, towers, fishing rods and outriggers is also advised, unless they’re part of a designated lightning-protection system. Some boaters also like to disconnect the connections and power leads to their antennas and other electronics, which are often damaged or destroyed during a strike or near strike.

Under no circumstances should the VHF radio be used during an electrical storm unless it’s an emergency (handhelds are OK). Also, be careful not to grab two metal objects, like a metal steering wheel and metal railing — that can be a deadly spot to be if there’s a strike. Some boaters opt to steer with a wooden spoon and keep their other hand in a pocket if forced to man the helm during a storm, while others like to wear rubber gloves for insulation.

Surviving Lightning Strikes While Boating

An open boat like a runabout is the most dangerous to human life during lightning storms, since you are the highest point and most likely to get hit if the boat is struck. If shore is out of reach, the advice is to drop anchor, remove all metal jewelry, put on life jackets and get low in the center of the boat. Definitely stay out of the water and stow the fishing rods.

If all goes well, the storm will blow past or rain itself out in 20 to 30 minutes. It’s best to wait at least 30 minutes until after the last clap of thunder to resume activities.

There’s a Zap For That

What to do when your boat is struck by lightning.

Knowing what to do in a storm and having the best lightning-protection system installed on the boat is by no means a guarantee that lightning won’t strike. The immediate checklist for a direct hit is very short:

1. Check for unconscious or injured persons first. If they’re moving and breathing, they’ll likely be OK. Immediately begin CPR on unconscious victims if a pulse and/or breathing is absent — there’s no danger of being shocked by someone just struck by lightning.

2. In the meantime, have someone check the bilges for water. It’s rare, but lightning can blow out a transducer or through-hull — or even just blow a hole in the boat. Plug the hole, get the bilge pumps running, work the bail bucket — whatever it takes to stay afloat. An emergency call on the VHF is warranted if the situation is dire. If the radio is toast, break out the flare kit.

If there are no injuries and no holes or major leaks below, just continue to wait it out. Once the danger has passed, check the operation of the engine and all electronics. Even a near strike can fry electronics and an engine’s electronic control unit, cutting off navigation, communication and even propulsion. Some boaters stash charged handheld VHF and GPS units and a spare engine ECU in the microwave or a tin box for this very reason. These makeshift Faraday cages have saved equipment.

One in 1,000 Boats Are Hit by Lightning Per Year

Obvious damage will need to be assessed and set right. Even those lucky enough to come away completely unscathed after lighting storms, with no apparent damage should have a professional survey done just to be sure. Minor damage to through-hulls can result in slow leaks, and all manner of electrical wackiness can emerge — sometimes much later. It’s best to catch these issues right away and get that information to the insurance folks for coverage.

Is Just a Ground Plate Enough?

On many levels, robust insurance coverage plays a huge role in your lightning-protection plan. Knowing how to avoid lighting storms and read the weather are certainly important, being ready for action in the event of a storm or strike is crucial, and an upfront investment in lightning protection can lessen destruction. When it comes to dealing with the aftermath of a damaging strike, however, extensive lightning strike coverage can’t be beat.

Take it from a luxury trawler owner who sustained more than $1 million in damage from a strike: “Boat insurance turns out to be the best investment we have made in the past 10 years!” he said. “We will never again grumble about writing a check for an insurance premium.”

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Yachting World

• Digital Edition

Expert sailing advice: How to handle a lightning strike on board

• August 21, 2019

Pip Hare shares advice from sailors who have experienced a lightning strike on how to avoid getting hit by an electrical storm

The 2015 Volvo Ocean Race encountered electrical storms. Credit: Brian Carlin / Team Vestas Wind

Lightning is the thing that scares me the most at sea. Having never experienced a lightning strike I think this is mostly a fear of the unknown, coupled with a sense of helplessness.

My lightning strategy has always been to sail in the opposite direction and hope for the best. The following is a combination of my own practice and observations from sailors who’ve experienced a lightning strike first-hand.

Avoiding lightning

Thunderstorms are created in conditions where there is great instability between the upper and the lower layers of the atmosphere. Typically, thunderstorms follow an extended period of warm, still weather , but lightning can also form along very active frontal systems – this tends to follow a sustained period of average pressure, with little gradient breeze when the new front moves in quickly.

Forecasters can predict where there will be increased potential for lightning to form, but not its actual occurrence or exact location.

Specialist forecast models such as the CAPE (convective available potential energy) and the LI (lifted index) show storm potential by highlighting areas of atmospheric instability.

CAPE and LI forecasts are available via specialist weather sites and CAPE GRIBs can be obtained through some providers. Satellite images can also be useful for spotting intense areas of cumulonimbus clouds.

If planning a sailing voyage in areas where lightning could be expected, include a CAPE forecast in your daily GRIB run.

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Flashes on the horizon

If you get caught out or have to sail through an area where electrical storms are expected, it’s important to prepare for all the weather a thunderstorm can dish out, not just lightning.

Thunder claps can be heard for around 25 miles, so if the sky on the other side of the horizon is alive with light but you can hear no noise then stay vigilant but don’t panic – the storm is still a way off. Keep moving.

Keep a 360° look-out: due to the immense height of thunderclouds they are pushed along by upper atmosphere wind, not the sea-level breeze. This makes it difficult to predict which way a cloud is moving, they can sneak up behind you while you are sailing upwind. The best way to track thunderclouds is using the radar or a hand-bearing compass.

Prepare for a squall: wind associated with thunderclouds can reach in excess of 40-90 knots in a matter of seconds, this will often be combined with torrential rain and drastically reduced visibility. If there’s lightning around it’s best to keep on-watch crew in the cockpit so make sure you reef early.

Preparing for a strike

Lightning can strike up to ten miles away from the cloud that generated it. Just because you are in the midst of a thunderstorm doesn’t mean you will get hit – I’ve spoken to two sailors who reported lightning striking the water next to their boat but not touching them.

Others that were struck reported varying damage to electrical equipment and none experienced structural damage or fire. Here are some of their recommendations:

• Unplug all masthead units, including wind instruments and VHF antennas and ensure ends of leads are kept apart to avoid arcing.
• As the storm gets closer turn off all electronics – modern kit has increasingly efficient internal protection, but manufacturers still advise turning it off.
• Take a fix and plot it on a paper chart. Update your log using dead reckoning.
• Avoid touching metal around the boat, such as shrouds and guardrails.
• A nearby strike will be blindingly bright. Sit in the cockpit until your night vision returns.
• Expect masthead units, VHF antennas and lights to be destroyed, so make sure you carry a good quality spare VHF antenna.
• Fluxgate compasses can lose calibration following a strike. Check all electronic compass readings with a handheld compass.

Maximising protection

By providing a direct route ‘to ground’ down which the lightning may conduct you may be able to minimise damage.

Among my small sample of interviewees, only one had a lightning protection system: this was a sloop with a deck-stepped mast on which the chainplates were bonded to the keel bolts. The masthead unit on this boat was still totally destroyed by the strike but the remaining electronics suffered no ill effects. The same sailor had experienced a strike two years earlier with no extra protection installed – in that instance all electronics were destroyed.

The remaining sailors were all in boats of less than ten years old and reported varying degrees of damage to electronics and 100% destruction of masthead units.

The simplest protection system is bonding an aluminium mast to the keel bolts. On a keel-stepped mast this is easily done as the mast heel and keel bolts are close to each other. For deck-stepped masts this can be achieved by running an adequately sized cable through the deck head and down a bulkhead or supporting pillar.

Most modern boats have the mast bonded to the keel by manufacturers – if you’re not sure lift the soleboards to check. Masts made of less conductive materials such as carbon would require a conductor cable as well.

Air terminals at least six inches higher than any antennas at the top of your mast may save your masthead units. There is also considerable debate over the need for dedicated grounding plates – this appears to be more relevant to older boats as none of my interviewees suffered ill effects through grounding to the keel bolts.

Faraday cage

There is a theory that the oven on a yacht can act as a Faraday cage, protecting anything inside it from the effects of electrostatic discharge (ESD). Handheld or portable electronics can be temporarily placed inside a metal oven to protect them during a storm.

I have no conclusive evidence this works, but I’ve always done it, reckoning it can’t do any harm – just remember to take them out before dinner!

How Often Do Sailboats Get Struck By Lightning?

Last Updated by

Daniel Wade

April 26, 2023

‍ Key Takeaways

• A lightning protection system can help mitigate a lightning strike.
• Lightning storms can form anytime when offshore sailing so prepare the best you can.
• If you see lightning strikes nearby you should move to the middle of the boat.
• Multihull sailboats attract lightning more than other types of boats.
• Perfect lightning protection does not exist so plan accordingly before sailing.

‍ Sailing during rough weather can be a dangerous situation. But how often do sailboats get struck by lightning?

Sailboats are hit with lightning strikes at a rate of four per 1,000 on average. Various boats in Florida on average have a rate of 3.3 out of 1,000, so location matters. The chance of any boat being struck by lightning in a given year is one in 1,000.

According to insurance claims for places like Florida that get hit with lightning strikes often every year, these numbers only reflect reported damage to sailboats. Marine surveyors warn that these numbers could be slightly higher so the chance of your boat being struck by lightning is still dangerous no matter how little or significant the risk is.

Table of contents

‍ The Chances of Sailboats Being Hit by a Lightning Strike

Some will argue that the size and type of your boat do not matter when it comes to lightning strikes. This is not true since some boats have been reported to be more susceptible to lightning strikes than others.

Lighting strikes are not your fault but there are some things you can do to help lower the chances of your sailboat being struck by lightning. While there is no guarantee in a lightning protection plan, having all materials and actions ready beforehand could save you money and someone’s life.

Multihull Sailboats

Multihull sailboats like catamarans or trimarans have a 6.9% chance of lightning strikes a year out of 1,000. Multihulls lack keels and with more exposed surface area face a greater risk of lightning strikes. Modern multihulls come with complex electronic systems that usually lead to costly damages from a lightning strike.

Monohull Sailboats

Monohull sailboats have a slightly lower occurrence of lightning strikes than multihull sailboats at 3.8% out of 1,000 per year. Just because they are less likely to be hit with lightning than multihulls does not mean you are in the clear.

Other Types of Boats

Other boats such as trawlers, bass boats, and even pontoon boats are at lower risk individually. These boats have less surface area and some are not even designed to be offshore where storms are intense. When combining those and all other boats besides sailboats, the risk of being struck by lightning is 0.9 out of 1,000.

Length of Sailboat

Your mast is an extension of your boat so you should sit and wait for the weather to pass before heading out to sea. According to Martin Uman, who leads the Lightning Research Group at the University of Florida , sailboats with 20 to 30 feet taller masts are almost three times more likely to be struck by lightning. This is due to the nature of electrical charge transfer between clouds and the ground despite lightning bolts being typically five miles long and one inch wide.

Sailing in the Rain

Rain clouds hold water and thunderstorm clouds carry electric charges. Interestingly enough, sailing in the rain is fine, but the accumulation of storm clouds is dangerous. Your focus should be on Nimbostratus and Cumulonimbus.

Nimbostratus clouds are flat, large, and closer to the ground. They can produce precipitation and span vast areas at a time. Safe boating in these conditions requires proper measures such as adequate rain protection, safety gear, GPS, and lighting for navigation and anchoring.

Why Are Sailboats a Target for Lightning Strikes?

Lightning strikes can hit boats during a lightning storm since some have metal masts and antennas. You are more susceptible to a lightning strike due to conductive material and turning your boat into a giant lightning rod.

This is especially true for sailboats with high aluminum masts since lightning can hit the mast before anywhere else on the boat. Fiberglass boats sitting low on the water are less likely to be struck by lightning.

How to Prepare for a Potential Lightning Strike

Boaters must be familiar with essential safety guidelines for thunderstorms. A practical approach to lightning protection is providing a safe discharge path for lightning. No technology currently exists to prevent lightning strikes so preparing for the worst is all you can do.

Update Insurance or Check the Policy

Ensure your sailboat has adequate insurance. If you do not have any or want to change you could always check out what BoatUS Marine insurance can do for you.

Seek Weather Updates

Equip modern weather detection gear and check the forecast before sailing. If thunderstorms are predicted you should stay in the harbor until the weather clears.

You can always tune into the VHF radio weather channel that is typically found on channels one through nine depending on your area. This gives you timely storm updates and critical information if you are out while a storm arrives.

If Stuck in the Middle of a Storm

Storms that will likely produce lightning strikes can pop up at a moment's notice at sea. If you are unable to outrun the storm, here are a few tips to consider:

• Wait it out and keep your shoes on while avoiding metal objects.
• Hold onto non-conductive items like fiberglass but beware that water can conduct electricity.
• Keep a hand in your pocket for safety and ensure no metal is inside.
• Use a vital piece of wood or rubber to control the steering wheel and set the throttles at idle or low throttle.
• Lower the antenna, outriggers, and any fishing rods.
• Stay close to the middle of the boat and remove any metal jewelry.
• If lightning strikes the boat you should immediately ask if everyone is okay and look for a hole that the lightning went through to ensure you are not taking on water.

Keeping Electronics Safe

It would be best to use transient voltage surge suppressors (TVSS) to safeguard crucial and lightning-sensitive equipment such as ECU/ECM, chart plotters, and instruments. These semiconductor devices suppress lightning-induced voltage spikes and are widely used in aviation, wind power, and telecommunications.

TVSSs function like voltage-sensitive fuses and redirect excess voltage as heat. Using TVSSs is a wise investment in preventing lightning damage to equipment even though this heat may damage them.

Ground Your Sailboat

For a grounding system, you should install lightning rods or terminals on top of the mast and connect them to the grounding plate to protect it from lightning. Use cable as a down conductor for wood or carbon masts and retrofit the grounding plate during haul out.

Monohulls require one plate, while ketches, yawls, and schooners need a path for each mast and a strip under the hull. Catamarans need two plates but a more extended plate outline is better for current dissipation.

Internal Bonding Circuit

A bonding system is a circuit inside a boat that links main metal objects to the grounding plate with cables. This reduces the risk of internal side strikes caused by current jumping between objects towards the ground.

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I've personally had thousands of questions about sailing and sailboats over the years. As I learn and experience sailing, and the community, I share the answers that work and make sense to me, here on Life of Sailing.

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Striking Lightning Facts

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An analysis of 10 years of lightning claims reveals which boats are most at risk.

Photo: C. Clark, NOAA Photo Library

Lightning seems like the ultimate "act of God." Unpredictable, capricious — it can come as a literal bolt out of the blue (or out of a glowering, black, anvil-shaped cloud). As the " Lowering the Lightning Odds " article in the July 2014 issue discussed, somewhere around one in a million people gets struck by lightning in any given year. Which means that someone must have it in for boats — two separate analyses of 10 years of lightning claims data from the BoatUS Marine Insurance files have found that about one in a thousand boats has a lightning claim each year.

When people get struck, it seems to be random. Yes, men get struck more than women (82 percent of lightning fatalities from 1995 to 2008 were men according to Popular Science ), but that's only because men spend more time outdoors and won't stop what they're doing for a little lightning. No one has yet suggested that tall people get struck more than short ones, or blondes are more at risk than brunettes. The same cannot be said for boats. The data shows that when it comes to lightning, not all boats are created equal. Certain boats are significantly more at risk than others. So which boats get hit, in which parts of the country, and how badly?

Which Boats?

While any boat can be hit — BoatUS Marine Insurance has even had some lightning claims for personal watercraft — lightning is most likely to go for that tall, tree-like metal pole sticking straight up toward the sky. The taller the better. That's why sailboats have significantly more lightning claims than powerboats (Table 1) , and almost certainly why larger boats have more lightning claims than smaller ones (Table 2) — overall size is closely correlated to mast height, which is probably what really matters here. And as far as lightning is concerned, two hulls are better than one. Multihull sailboats are almost twice as likely to have a lightning claim as monohulls. But that's only true if that big, pointy thing is in the middle of the boat. The frequency of pontoon boat lightning claims is well below the average.

Table 1. The probability of a lightning strike by type of boat, 2003–2013

Table 2. the probability of a lightning strike by size of boat, 2003–2013.

According to Martin Uman of the University of Florida's Lightning Research Group, the average lightning bolt is an inch wide and five miles long. On the face of it, it seems unlikely that 20 or 30 feet more height — roughly the difference between the mast on a 35-foot and 45-foot sailboat — would almost triple the odds of the boat being hit. But understanding how the electrical charge that passes through a lightning bolt moves between the clouds and the ground makes lightning seem just a bit less capricious.

This boat burned after a lightning strike; fortunately strikes usually don't cause fires aboard.

Lightning is a direct result of the electrical forces built up in the clouds during a thunderstorm, where the bottom of the storm cloud becomes highly negatively charged. Only 20 percent of lightning strikes actually reach the ground — the rest are cloud-to-cloud strikes. A typical cloud-to-ground lightning strike occurs in less than 1/100 of a second but actually proceeds through four distinct phases. The following is an abbreviated version of the National Weather Service's JetStreamMax Online School for Weather's lightning discussion.

1. Development of the stepped leader from the cloud base. A very faint, negatively charged channel emerges from the base of the cloud and propagates toward the ground in a series of small steps about 150 feet in length and 1 microsecond in duration. The stepped leader carries about 100 million volts of charge relative to the ground. It usually branches out as it approaches the ground, pausing between each step and "looking" for an object to strike.

2. Development of streamers from objects on the ground. The strong, negative charge of the stepped leader attracts vast amounts of positive charge. The attraction is so strong that the stepped leader induces electric channels up from the ground known as streamers, most readily from tall, pointy objects. When a cloud-to-ground strike occurs, one of these positively charged streamers connects with the negatively charged stepped leader, at 100 to 300 feet above the ground on average.

3. Negative charge flows downward. When that connection occurs, the negative charge from the cloud starts flowing down the established channel.

4. Return stroke shoots up the channel. Once the channel is open, the return stroke flows up and produces a ground current that peaks in about 1 microsecond at an average of around 30,000 amperes. The return stroke produces 99 percent of a lightning bolt's luminosity, and, though it travels from the ground up to the cloud, to the unaided eye the opposite appears true.

Sailboat masts, like tall trees, seem to be at just the right height and of just the right shape to develop streamers that the stepped leader can reach when it's "looking" for a place to touch down. That doesn't explain why one mast in a particular marina wins the lightning lottery, nor does it mean that the highest object will always be struck. But when looking at probabilities, the claims data suggests that sailboat masts must make better lightning rods than other appendages on other types of boats.

This "lightning track" shows how the electrical charge passed from the bobstay to the jackstand to reach the ground.

Understanding why multihulls get hit so much more frequently than monohulls is more problematic. Several theories have been put forward including the lack of a keel, the increased wetted surface area, the larger footprint, the location of catamarans at the edges of marinas, the overall size of catamarans, and the average height of their masts. Unfortunately, we do not yet have enough data to be certain of what is driving this finding.

Not surprisingly, boats get struck where there is a high density of lightning and a high density of boats. The frequency of the BoatUS lightning claims by state fairly closely resembles the incidence of cloud-to-ground lightning strikes. If an area has a high incidence of strikes, that includes a lot of masts, it's not too unlikely that one of those strikes will find its way to ground through a boat.

Six of our top 10 states in terms of the frequency of lightning claims — Florida, Mississippi, Louisiana, Alabama, South Carolina, and North Carolina — are part of the big "hot spot" in the Southeast and midsection of the country. Maryland ties for second with Mississippi, which might surprise you. But there are a lot of sailboats there, and anyone who has boated on the Chesapeake Bay in the summer has experienced the fast-moving and violent thunderstorms that sweep through the area several times each month from June through September.

At the other end of the spectrum, the frequency of lightning claims is about 1 in 10,000, or one-tenth the average, along the Pacific coast. That doesn't mean that BoatUS Marine Insurance doesn't ever have lightning claims there, only that if you are the one with the claim, you've been very unlucky indeed.

What Type Of Damage?

Yes, the old wives' tales are true. Lightning can blow a thru-hull right out of the boat, but more commonly its passage through a metal fitting damages the surrounding fiberglass. This can be severe enough that the boat sinks. Boats on the hard often fare even worse than those in the water — the lightning will find its way to the jackstands or chains, often leaving a visible track across the hull. But extreme damage from lightning is the exception, not the rule.

Examples of lightning damage.

More than 75 percent of lightning claims in the BoatUS Marine Insurance files over the past decade were for less than 30 percent of the insured value of the boat. And nearly all of those claims were for damaged electronics. Here's how it normally goes. Joe and Jane Boater arrive at the marina looking forward to a lovely weekend on the water. They begin loading all their stuff onto their sailboat. Jane goes down below to put things away and says, "Joe, did you leave the breaker for the fridge off?" A bit later, Joe tries the chartplotter but it won't fire up. Then the microwave won't work. It takes awhile before the penny drops. One of them looks at the other and says, "Remember that big thunderstorm last week? Maybe our boat got hit."

If this ever happens to you, don't assume the damage is limited to the electronics. To make sure your boat is safe, you should do the following:

1. Unplug the shorepower cord and turn off all battery switches. You don't want a short circuit to start a fire.

2. Check the bilge and make sure it is dry. If it is not, arrange a haulout immediately. This will probably be covered by the insurance company, but even if it isn't, you need to make sure everything is OK below the waterline.

3. Call your insurance company. Tell them what is happening, and don't forget to discuss a haulout if you are taking on water.

4. Once you're sure the boat isn't sinking or you have hauled it out so it can't, your insurance company will assign a marine surveyor to do a damage assessment, inspecting the electronics and all electrical panels to figure out what does and does not work. Electronics may need to be bench tested to establish that lightning was the cause of the damage. If you haven't been hauled out and the damage appears extensive, the insurance company may require a haulout now to ensure there is no below-waterline damage.

5. Don't throw away any damaged equipment unless your insurance company says it's OK to do so.

So, if you have a sailboat in a lightning hot spot, especially if it has two hulls, you are more at risk than average. What can you do about that? The general consensus is, you can't do much to keep your boat from being struck. The ultimate act of God, remember, though God seems to have it in for sailboats and doubly so for multihull sailboats. But lightning protection systems can help to minimize the damage if your boat does get struck, so we will be looking at those later this year.

What To Do If You're Caught Out On The Water

"When thunder roars, go indoors." If there is time, return to shore and take shelter in an enclosed building (not open-sided) or your car. They are not impervious to lightning, but the lightning is less likely to do damage.

But if lightning has already begun, getting closer to shore may bring you close to trees and other objects that could be lightning targets. In that case, stay on the boat and do the following:

• Go indoors — go down below. Stay in the center of the cabin if the boat is so designed. If no enclosure (cabin) is available, stay low in the boat. Don't turn yourself into a lightning rod!
• Keep arms and legs in the boat. Do not dangle them in the water.
• Discontinue fishing, waterskiing, scuba diving, swimming, or other water activity when there is lightning or even when weather conditions look threatening. The first lightning strike can be a mile or more in front of an approaching thunderstorm cloud.
• Disconnect and do not use or touch major electronic equipment, including the radio, throughout the duration of the storm.
• Lower, remove, or tie down the radio antenna and other protruding devices if they are not part of the lightning protection system.
• To the degree possible, avoid making contact with any portion of the boat connected to the lightning protection system.
• On larger boats with an oven or microwave, putting electronics inside should prevent them from being damaged as the oven or microwave will act as a Farraday cage, allowing the charge to pass harmlessly through the metal around the devices.

Source: University of Florida's "Boating-Lightning Protection" by William Becker

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Lightning Safety

The threat of lightning is easy to ignore on an overcast summer day, but it can kill unprepared boaters without warning. Carrying as much as 100 million volts, it can smash a hole through a hull, explode a mast, and electrocute several people in a single flash. The thunderstorms of the Chesapeake Bay pose a lightning threat every boater should know about.

What is Lightning?

Lightning is nature’s way of equalizing conflicting charges in the atmosphere. These charged form most often when cool and warm air masses collide.

During a storm, negative charges build up in the base of clouds. As they pass over the earth, they create a positive charge in the normally negatively charged terrain. The positive charge works its way up tall objects, pulled along by the negatively charged clouds. As the positive charge forms an arc, lightning strikes.

How Dangerous is Lightning?

In the United States, lightning consistently kills more than 100 people per year. That’s more than other natural disasters, such as hurricanes, floods, or tornadoes. Risks are especially high for those who spend time outdoors, including farmers, fishermen, or boaters.

Water and lightning are a natural combination. Water conducts electricity very well, and when you add in the high profile of a boat surrounded by open water, there is an increased danger of getting electrocuted during a storm.

Take steps to stay safe. Here are tips from Maryland Sea Grant and University of Maryland Extension. Click on each heading to learn more.

What Can You Do?

To protect yourself in a boat, the important thing is to give lightning a ground. Boats made of steel, such as naval vessels, have an automatic ground in their metal hulls; but most small boats, usually constructed of fiberglass or wood, prevent the lightning easy access to the water and pose a grounding problem. Small boats may also lack tall objects that could deflect lightning. And even boats that do have tall spars -- like sailboats -- can run into problems if their spars are not properly grounded. The following grounding system will minimize the risk of lightning damage:

• On a sailboat, make a lightning rod using a piece of aluminum that sticks about 1 foot (30.48 centimeters) above the mast. Sharpen the rod to reduce resistance at the top. A radio antenna can also conduct electricity but may lead lightning to the radio and may well vaporize it during a strike.
• From the rod, lead a wire down a wooden mast; an aluminum mast can serve as its own conductor as long as a wire is led from its base to direct the charge to the ground. (A wooden mast with a metal sail track can be grounded as though it were a metal mast.) The Coast Guard finds a #8 wire adequate, though a larger gauge, say #4, further reduces heat and resistance.​​

• Attach this wire to a copper ground plate mounted on the hull beneath the waterline or dangled underwater. A square foot of copper flashing, easily obtained at many hardware stores, will make an adequate ground plate. If you decide to attach a permanent ground, use large stainless steel bolts, say 1/2 inch, to prevent their cracking under large electrical discharge. To increase safety, some recommend all stays be grounded to the plate.
• On a motorboat that has no high spar, use a metal radio antenna (not a fiberglass one), attaching a wire to a ground plate, as described above. If there is a loading coil on the antenna, use a shunt of 31-strand, 17-gauge, bare lightning grounding mesh to bypass it -- this will make the whole height of the antenna an effective ground. Quick-release clamps will allow an easy temporary attachment. (On a fiberglass antenna you can clamp the wire to a metal rod, letting that act as a lightning interceptor.) Use a "lightning arrestor" to protect your radio.
• When leading the wire to a ground, avoid sharp bends or turns. Any bend in the wire should have a radius of at least 60 degrees.
• One alternative calls for leading the grounding wire to a metal strip that runs down the bow or stern and maintains constant contact with the water. This offers the advantage of carrying the charge, at a gradual angle, safely away from the engine and the helm.
• Both the mast and the whip antenna will provide a "cone of protection" with a radius of approximately the same dimension as the rod's height. For most small boats, this will include the entire deck area. There may be, however, induced electrical surges created by the lightning, and for this reason large metal objects -- engines, for example - should be avoided during a storm. (Remember that an engine will have its own ground in the propeller and the shaft.) Induced electrical charges can cause arcing and electrical shocks strong enough to knock you unconscious, perhaps producing dangerous heart arrhythmias. A lightning strike can also magnetize a keel or other, metal fittings, rendering your compass useless.

First Aid for Lightning

After a shipboard lightning strike, check to see that everyone is all right -- it is, of course, perfectly safe to handle someone who has been hit by lightning. Check for burns, which should receive normal first aid treatment. (Don't put ointment on severe burns; cover them with clean cloth or plastic to keep out air.)

If someone has been knocked unconscious, act immediately: check for breathing and heartbeat.

If you feel a pulse, but no breathing, begin mouth-to-mouth resuscitation (a handkerchief over the mouth will help the squeamish). If there is no heartbeat, begin cardiopulmonary resuscitation, a technique every serious boater should know.

Precautions

Grounding your boat and unplugging radios and electrical equipment during a storm are good ideas, but the best precaution against lightning is avoidance. Especially in small craft, keep a weather eye out for the coppery haze and building cumulonimbus clouds that signal thunderstorms, heading ashore well ahead of the turbulence.

Remember that lightning can lash out for miles in front of a storm, and it can strike after a storm has seemingly passed. Remember, too, that, storms can bring high winds and waves, making a last-minute trip to shore a dangerous dash. The best maneuver of all is to think ahead.

Download a pdf of our brochure, Lightning: Grounding Your Boat,  containing this information.

Photograph of lightning, NOAA

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A Quick Comprehensive Guide to Lightning Protection for Boats

Understanding Lightning Mitigation for Boats

Techniques to lessen the impact of a lightning strike, adopting standardized lightning protection for boats, key components of a boat's lightning protection system: wiring, air, and ground terminals.

Also Read: Marine Electronics - Discover The Latest Award-Winning Products For 2023

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Protecting Your Boat From Lightning Strikes

Most boat owners have only the vaguest idea of what is involved in protecting their boats from lightning damage. Many believe that their boats are already protected by the boat’s grounding system. Most are wrong.

Just because your boat may be bonded with heavy copper conductors connecting the masses of metal in the boat doesn’t mean that it is protected against lightning. A bonding system may be a part of a lightning protection system, but bonding itself offers no protection to the boat unless a good, direct path to ground is part of the system.

While neither aluminum nor stainless steel is an outstanding electrical conductor, the large cross-sectional area of both the mast and the rigging provide adequate conductivity for lightning protection. The trick, however, is getting the electricity from the mast and rigging to the water.

The straighter the path is from conductor (mast and rigging) to ground, the less likely are potentially dangerous side flashes. Put simply, side flashes are miniature lightning bolts which leap from the surface of the conductor to adjacent metal masses due to the difference in electrical potential between the charged conductor and the near by mass of metal. Ideally, therefore, the path from the bottom of the mast and rigging to ground would be absolutely vertical. In practice, this is rarely achieved.

If the boat has an external metal keel, the mast and standing rigging is frequently grounded to a keelbolt. There are pitfalls to this method. First, the connection between the bottom of the mast and rigging to the keelbolt must be highly conductive. ABYC (American Boat and Yacht Council) standard TE-4 for lightning protection systems require that these secondary conductors have a conductivity at least equal to that of AWG #6 copper-strand cable. There is no drawback to using an even larger conductor.

Connecting the short conductor to the mast and keelbolt presents some problems. A crimp eye can be used on the end that is to be attached to the mast, but you may have to fabricate a larger eye for attachment to the keelbolt. This can be made from sheet copper. Soldering the connections is not recommended, since the heat generated in a lightning strike could melt the solder.

Then you have to face up to a basic problem. Your mast is aluminum, yet you’re connecting it to ground with a copper cable. Everyone knows that aluminum and copper are not galvanically compatible, so what’s the solution? While it will not eliminate corrosion, a stainless steel washer placed between the copper cable’s end fitting and the aluminum mast will at least retard it. But this connection is going to require yearly examination to make sure that a hole isn’t being eaten through the mast. In addition, of course, the process of corrosion creates wonderful aluminum oxide byproducts, which have very low conductivity. The aluminum oxide may reduce conductivity to the point where your theoretical attachment to ground is in fact non-existent. Once again, disassembling the connection and cleaning it yearly are essential to maintain conductivity. Constant attention to all the conductor connections is essential in any grounding system, whether it’s for lightning protection or grounding of the electrical system.

For more information on how to best protect your boat from lightning strikes, purchase Nigel Calder’s Boatowner’s Mechanical & Electrical Manual from Practical Sailor .

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Family Day Sailing... World Class Racing The Best of Both Worlds!

• Design: Sparkman & Stephens, 1938
• Over 15000 built
• More than 100 active fleets worldwide
• Length: 19'0" (5.8m)
• Beam: 6'6" (2m)
• Displacement: 700 lb (318 kg
• Draft (board down): 4'11" (151.3cm), (board up): 5" (12.8cm
• Mast height: 26'2" (7.9m)
• Sail area (main & jib): 177 sq.ft.
• (spinnaker): 300 sq.ft.
• Crew (racing): 3

The International Lightning

Get the best of both worlds without compromising either, dinghy responsiveness sportboat performance the best of both worlds, refined design, today's technology the best of both worlds, the best competition in the world or a way to get away from it the best of both worlds , club racer or international icon the best of both worlds.

The ILCA is one of the oldest and best organized class associations in sailboat racing. Its primary purpose is to serve its membership, preserve the integrity of the Lightning and provide high-quality competitive events. In addition, the ILCA publishes a monthly newsletter Lightning Flashes with up-to-date regatta news, boat brokerage and ideas on how to get the most out of your Lightning. An annual Yearbook, containing many illustrated articles, reports on major championships, fleet reports and a complete association mailing list, is also published. The professional ILCA staff is always on hand to assist both current and potential members. If you're looking for a boat you can be proud to sail, one that offers dinghy handling with the performance of a sportboat, a refined design that's free of fads, complete with the technology of today for both racing and daysailing - Get The Best Of Both Worlds. Get into a Lightning. See you on the water. David Dellenbaugh, former Lightning World Champion and starting helmsman for 1992 America's Cup defender America3, lists the top ten things he likes about the Lightning:

• There's Lightning racing almost everywhere.
• Some of the best sailors in the world sail the Lightning.
• Lightnings are available from more than one high-quality builder.
• Lightnings even 20 years old are still competitive.
• The boat is one of the best crew trainers on the water today.
• The class is not so strict as to discourage experimentation which makes the boat faster and easier to sail.
• The Lightning has interested the finest sailmakers in the world so the sails and the tuning guides look great and are easy to use.
• The Lightning is a very roomy boat for daysailing.
• Lightning sailors sail hard, but they're not too cutthroat - someone's always ready to answer questions.
• The class management is as good as you'll find in one-design sailing.

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Lightning and sailboats

• Thread starter Cpt. Jon
• Start date Mar 18, 2009
• Forums for All Owners
• Ask All Sailors

Hello, I know this is very long, but I wanted to share the experience that leads to the questions at the bottom. With another infant on the way and a ‘new to us’ boat again, this memory has come back and years later I still don’t know the answer to the questions below about lightning. I am hoping that some of you will have some knowledge and/or experience(s) to share with the community. Thanks, and I hope you enjoy the long read! My wife, 6 month old daughter (at the time), and I set out on our maiden voyage in our sailboat a few years ago. The weather was beautiful and it was mid-afternoon very early summer. Enough time for us to sail leisurely and motor-sail if needed to get the boat home from the yard with plenty of time to spare. We didn’t check an updated forecast or radar which turned out to be one of the biggest learning mistakes we’ve ever made. We got clobbered by 3 severe thunderstorms for 3 hours, with winds topping 50+mph and over 1000+ lightning strikes in our area in those 3 hours. By the time the storms were closing in on us, we were at the mouth of the York River heading into the Chesapeake; I had to go with my instinct which was to find a sheltered place to ride it out, we couldn’t make it back to the marina in time. I tried to get into a channel that I normally can get into at anything but low tide, and started to rub the bottom, I decided that I didn’t want to be aground with high winds and this storm and made a quick turn back out deep enough be clear and we were sheltered enough there that big waves off the Chesapeake and York shouldn’t effect us too much. I dropped anchor and set it well and we sheltered below. For the next three hours of phone calls, and coast guard chatter about capsized boats on the bay by this sudden storm on the radio, I kept wondering if we were doing the right thing. I didn’t want to be on deck in the event of a lightning strike, but I REALLY didn’t know if it was safer below. The mast is deck stepped and I figured the whole hull may basically become charged in the event of a lightning strike, and a keel stepped mast would have been safer. As the boat wandered back and forth on the anchor line in the gusts and at times heeled so much that it seemed we may get knocked down, my daughter slept peacefully through the WHOLE ordeal, I had fear of a lightning strike or something else and was prepared to have to call the coast guard and ‘abandon ship’ if the time came. My wife was calm and seemed to have more faith in the boat and my decisions… I grew up on the water, have lived on the water most of my life, but rarely have I been in a situation like this (a few experiences in Iraq being an exception), motor boats can outrun storms, but you can’t outrun much at 5 knots (lesson learned). Eventually, the storm started to clear, visibility got better, and the lightning subsided. I pulled anchor, and we made a B-line back for the marina, which was closed at this time. The sun was out that evening and it was once again peaceful. Some friends met us at the marina with some towels, food, and dry clothes (sailors as well and the friends that we bought the boat from). They worried the whole time we were out there and we’ve talked about it numerous times. In the end, just about everybody I’ve talked to said that I made the right decision to ride it out as we did, and I almost always go with my instincts. I installed a radar application on my cell phone the next day and we’ve never been on the water in a storm since, but it’s a matter of time, not every cruise can be as lucky as we have been the last couple of years. My questions are: What about lightning? With all that lightning around, I can’t believe we didn’t get struck, to be honest. I am glad that we were fairly close to shore because the trees were more likely to get struck, I guess. What happens when a sailboat gets struck? What is the safe course of action in a situation like we were in? Where should you be in the boat in a lightning storm? I assume away from metal and the bulkhead under the mast, we were near the companionway and my daughter was sleeping on the bed made from the settee table and benches. Thanks for the input, Jon  

Interesting. My boat was struck while in the slip. I was not aboard. You can see my slip on Google Earth at 30º21’ 04.96 N and 90º03’13.42W. There are trees close by (within 55 feet) that are higher than my mast which is 53 feet to the top of the VHF. The VHF aerial and the radio itself were smoked. The light bulb in the AC panel for the reverse polarity indicator was blown across the cabin and was on the table. The light bulb in the stern navigation light was exploded. The steaming light and mast-top anchor light were fine. The nav light breaker on the electrical panel had the aft end of its case blown off but it still functioned. The power fuse in my old LORAN was blown out but it works fine after the fuse was replaced. The aerial is on the stern rail, close to the stern light. The antenna coupler in the base of the aerial was not damaged. There are interesting oxidation trails in the black paint on the back side of the electric panel, travelling from the blown nav light breaker case to the green ground buss of the AC panel. I had replaced all of the indicator lights of the DC panel with LED’s and all are still functional. Sorry about the blurry pictures. Some of the Interlux 2000 barrier coat on the iron keel was blistered when I pulled the boat three years later, but I don’t know if that was caused by the lightning leaving the keel or was (more likely) due to the crappy yard work. While anchoring during a storm off Horn Island, Mississippi, a few years back, lightning hit the water about 300 yards away.. Nothing taller than my mast for a few miles.. Leaving Gulfport, still in the channel, for the start of the Gulfport To Pensacola Race, a J-30 about 100 yards in front of us was hit on the mast top. We saw the VHF aerial blow up, lots of fire up there for a second. There were 5 people in the cockpit.. We could see that they were very excited for a few seconds but everyone was fine and they finished the race.. They lost their wind instruments in addition to the VHF. No one can predict..  

Attachments

Dropping anchor is a good storm tactic if you have decent ground tackle. If you have an all chain rode, that might increase your chances of getting hit. Thre are basically two schools of thought on lightning and boats. The first is that you should ground the mast and have heavy bonding between the stanchions, chainplates, pulpit and such to the mast. This should give you more protection in the case of a lightning strike by forming a "Faraday Cage" to protect the occupants of the boat. However, statistically, boats that are well grounded tend to get hit a bit more often. The second school of thought is that you shouldn't ground your boat. The idea being that you're less likely to get hit. However, if you do get hit, the damage tends to be much greater. If you have a keel-stepped aluminum mast, creating a lightning ground path is relatively easy. For boats with deck-stepped or non-aluminum masts, it is a bit more difficult.  

Sounds like you did all the right things. Lightning is an interesting phenomenon. It's unpredictable and random in the way it impacts what it hits. We had a near miss a few years ago. While trying to avoid one set of cells we encountered another. Knowing we couldn't dodge it we motored on. I watched my wind display go blank and moments later a bolt struck about 100 yards out. Nothing else around but us. No damage to the boat. I also know of two others that have been hit, both while tied to a slip. One was a power boat, the other a sail. Both sustained losses to their electronics. I've also heard in rare cases of thru hulls being melted. As for your hull becoming "live" that wont happen as it's fiberglass and wont conduct electricity. The mast and shrouds should shunt it safely away from you. Actually the cockpit is a safe zone in that all the metal surrounding it forms a cage. The metal in the cage conducts the charge thereby keeping you safe. That said I'll add that it's wise not to hang onto or lean against anything metal during a storm as the voltages lightning produces are quite large and can potentially harm you if you're touching metal during a strike. Some times it's just a matter of hanging on for good luck. Mike  

Lightning is so unpredictable that you can do everything known to the mind of man and you neighbor can do nothing and for the next fifty years neither of you will get hit. In a marina with a thousand boats one may get hit and it may not be the tallest, it may be in the middle of the fleet or it may be out at the edge. It may or may not have any provisions for lightning abatment.  

Talked to a guy at the marina one day. He told me this story: He and his wife got caught in a thunderstorm. They were anchored fairly in the open near Turkey Point on the Chesapeake. Took shelter below. During the storm they heard a loud BOOM. (I forget if they saw a flash or not.) After the storm passed he hopped over the side (Mac 26 wth the keel swung up in shallow water) to inspect the boat. He found what at first he thought was some "fly crap" just above the water line. Then he noticed that the specks formed a line. Some time later in the the they both began to feel ill. Nausea and trouble thinking. They went to the Doc. He said "You've been hit by lightning". The specks of flly doo..... pinholes in the hull.  

Mike B said: Capt Jon, it's a good time to convert that tiller to a nice wood one Click to expand

We had an old dead snag in the back yard year ago. It was about 75 yards from the house. One night we had a storm and lightning hit that tree with a boom like a couple of sticks of dynamite. The next morning I found chunks of bark within thirty feet of the house. I hate to think what a strike of the force could do to a house or a boat.  

Chris Burti

I can relate my experience for whatever that may be worth. We sail in an area prone to frequent and sudden summer squalls that are often accompanied by high winds, driving rain, hail and lightning. If you are going to sail in the summer around here, you are going to have to risk it some. That is not to say that I would voluntarily be out in a bad forecast. Enough experience with these squalls makes you just comfortable enough to forgo putting on a pair of Depends with your foul weather gear yet leaves you as nervous as fox in a pack of hounds. When I see a squall line approaching, I immediately drop and secure all sails and lines. I rarely anchor because I don't trust a hastily set anchor in those conditions, though many do. Assuming that the squall will miss you is a sure invitation to disaster. However. they usually pass quickly, but you should expect the wind direction to reverse itself and end up with a significant shift. You should expect gusts up to 40 knots which can lay you over to 30 degrees under bare poles and will knock you flat if any sails are up or break free. Hail can be painful and horizontal driving rain will make it difficult to see. Visibility will drop to less than a boat length. I've seen lightning hit the water less than a boat length away on several occasions. I've been hit by lightning just once while aboard in over forty years of sailing. Wouldn't care to repeat the experience. I was at the wheel of a friend's Pearson and the rest of the crew was down below with instructions to stay as clear as possible of chainplates, mast and electrical panel. When the lightning hit, I saw a blinding flash, but didn't notice much sound. The crew later reported hearing a huge boom and feeling tingly, but didn't notice any flash...go figure. Immediately after the flash, I saw molten metal hitting the foredeck. I reflexively jerked my hands off the stainless steel wheel. My first conscious thought to myself was "Well Cap'n Stupid...that's a pretty dumb move...too late now to zap you!" Insurance (less the deductible) took care of the VHF whip, Wind sensor and Windex, all of which were vaporised, the damage survey, haul-out, and the replacement instruments. The only real damage to the instruments was that the SeaTalk capability was fried and the hull survey came out clean. You kept your head, made difficult decisions and kept your vessel and crew safe in trying conditions and did not add to the risks. My experience leads me to offer no criticism whatsoever to your handling of your situation. I have seen no substantiated, quantitative scientific evidence that any particular anti-lightning trick or device is materially any better than any other or even better than snake oil. In this context, 'random' is more than a mere buzz word, pardon the puns. I would suggest that while second guessing in a storm is normal, changing one's mind in the middle of a crisis when circumstances haven't leads to poor decision making.  

kloudie1 said: There are trees close by (within 55 feet) that are higher than my mast which is 53 feet to the top of the VHF. The VHF aerial and the radio itself were smoked. No one can predict.. Click to expand

Remember that the wheel (ok, most wheels) is connected directly to the metal skeleton (ground) of the rudder through cables and chains.. More stuff .. The mast on the Hunter 34 is deck stepped but it does have a heavy wire, 8 ga, straight through the compression post to the keel. The wire was closely inspected after the hit and no problem was found. The chainplates are grounded that way as well. Another hit story.. The guy I sold my Spirit 23 trailer-sailor to a few years back was hit. He was in the cockpit and his wife was inside the cabin. He was hanging onto the wood tiller and reported a flash and a lot of bang, but was fine, other than commenting that his laundry folks would know how scared he was. There was no mast ground. Wife in the cabin reported a flash inside along with a pop. The cabin overhead lights (3) all blew up, spreading glass all over. The lightning went through the hull on its way out . The hull had two spots about 1 foot square on each side of the keel where the resin had been pretty much melted through leaving those spots oozing seawater through the glass mat into the boat. They were able to get to the yard using a manual pump every 10 minutes or so for the three hours it took to get to the yard and put her into the slings of the Travelift ® . The keel on that boat is a fiberglass shell molded into the hull into which a bunch of lead shot is poured and sealed with epoxy (no ground available). The swing keel has no metal in it, other than the lift bail and pennant. You are right, Jim.. I’ve done the same for tall pressure vessels in petrochem plants but what strikes ya (small pun there) is how small the cone actually is, which leads to the strange patterns of strikes amongst a forest of tall things. My neighbor’s mast top vhf antenna is outside of my cone but he had no damage from “feeders” at all.  

Lightning is crazy stuff. I've never been hit while on the boat, but I get real nervous in thunderstorms. Several years ago I was enjoying a cold beverage under my house (my house is on 8ft pilings) with my next door neighbor when the house across the street was hit by lightning. A side flash traveled 100ft to where we were standing. My next door neighbor was knocked to the ground and I had lightning flash into the palm of my hand from the metal door that I was standing near. He was unhurt, but it took me a couple of years to recover from the nerve damage to my right arm. The house across the street lost almost every electrical item. I hate lightning.:cussing:  

Here is a link dedicated to research on lightning by the U. of Florida (lightning capital of the US): http://www.lightning.ece.ufl.edu/ and more specifically related to lightning and boating: http://www.cdc.gov/NASD/docs/d000001-d000100/d000007/d000007.html  

The Faraday concept is demonstrated in this video of a high tension line worker. interesting video http://www.youtube.com/watch?v=EQYDToVK6Z0 My boat got hit in its slip and cost the insurance company over 4k. This is what it did to my battery charger located in the engine compartment of my old Irwin. All ohter electronics were toast and allthrough hulls had to be replaced.  

I don't know how much the man in that video makes but it's not nearly enough. Better him than me up there.  

Seen that video before... They don't pay that guy enough IMHO. That suit, being Nomex and Stainless Steel, must heat up on a hot summer day like nothing else...  

Insulators - No such thing in a thunderstorm When it comes to lightning there is no such thing as an insulator. A 'spark' which can travel thousands of feet in air will have no trouble in passing through fibreglass or wood - either through the laminate or along it. Indeed it can easily carbonise the material in an instant whence it becomes a good conductor. The Faraday cage theory is the best idea yet (I once did physics experiments in the lab where Faraday worked). The 'cage' is theoretically a cone 45° cone from the masthead - but my boat has no backstay! Lightning storms are often quite localised and on two occasions I have monitored the track and then sailed right round the storm noting the extraordinary wind changes as we went - the wind blows towards the center so we sailed a course round half a circle whilst close hauled all the time. Once we weighed anchor and left the cove we were in because we were directly in its path. As a result we saw nothing of the big winds in the centre. Fortunately we found searoom for this but it only required a couple of miles deviation. As Ross says lightning is so very unpredictable as to where it will strike. I also subscribe to the concept that it could be best to be near to something tall and conductive like another taller boat; but so why do they tell you not to stand under a tree? Many golfers die this way.  

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• Sailboat Guide

Lightning is a 18 ′ 11 ″ / 5.8 m monohull sailboat designed by Sparkman & Stephens and built by Nickels Boat Works, Inc., Skaneateles Boat & Canoe Co., Helms - Jack A. Helms Co., Siddons & Sindle, Lippincott Boat Works, J.J. Taylor and Sons Ltd., Lockley Newport Boats, Eichenlaub Boat Co., Mobjack Manufacturing Corp., Clark Boat Company, Allen Boat Co., and Loftland Sail-craft Inc. starting in 1938.

Rig and Sails

Auxilary power, accomodations, calculations.

The theoretical maximum speed that a displacement hull can move efficiently through the water is determined by it's waterline length and displacement. It may be unable to reach this speed if the boat is underpowered or heavily loaded, though it may exceed this speed given enough power. Read more.

Classic hull speed formula:

Hull Speed = 1.34 x √LWL

Max Speed/Length ratio = 8.26 ÷ Displacement/Length ratio .311 Hull Speed = Max Speed/Length ratio x √LWL

Sail Area / Displacement Ratio

A measure of the power of the sails relative to the weight of the boat. The higher the number, the higher the performance, but the harder the boat will be to handle. This ratio is a "non-dimensional" value that facilitates comparisons between boats of different types and sizes. Read more.

SA/D = SA ÷ (D ÷ 64) 2/3

• SA : Sail area in square feet, derived by adding the mainsail area to 100% of the foretriangle area (the lateral area above the deck between the mast and the forestay).
• D : Displacement in pounds.

Ballast / Displacement Ratio

A measure of the stability of a boat's hull that suggests how well a monohull will stand up to its sails. The ballast displacement ratio indicates how much of the weight of a boat is placed for maximum stability against capsizing and is an indicator of stiffness and resistance to capsize.

Ballast / Displacement * 100

Displacement / Length Ratio

A measure of the weight of the boat relative to it's length at the waterline. The higher a boat’s D/L ratio, the more easily it will carry a load and the more comfortable its motion will be. The lower a boat's ratio is, the less power it takes to drive the boat to its nominal hull speed or beyond. Read more.

D/L = (D ÷ 2240) ÷ (0.01 x LWL)³

• D: Displacement of the boat in pounds.
• LWL: Waterline length in feet

Comfort Ratio

This ratio assess how quickly and abruptly a boat’s hull reacts to waves in a significant seaway, these being the elements of a boat’s motion most likely to cause seasickness. Read more.

Comfort ratio = D ÷ (.65 x (.7 LWL + .3 LOA) x Beam 1.33 )

• D: Displacement of the boat in pounds
• LOA: Length overall in feet
• Beam: Width of boat at the widest point in feet

Capsize Screening Formula

This formula attempts to indicate whether a given boat might be too wide and light to readily right itself after being overturned in extreme conditions. Read more.

CSV = Beam ÷ ³√(D / 64)

One of the most popular one-design classes in the US since the 1940’s. But fleets also exist in other parts of the world. Although originally designed for wood planked construction, nearly all boats since the early 1960’s have been built of fiberglass. Ballast above is max weight of centerboard.

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Couple stranded in Bahamas after lightning strikes, destroys boat: ‘All mighty bang’

A British couple who spent their life savings to buy a sailboat and enjoy their retirement at sea are now stranded in the Bahamas after their dream vessel was struck by lightning — and the duo are in a race against time to fix it before the hurricane season starts

Mike Beech, 63, and his wife Helen, 61, spent $63,000 to buy the 38-foot Mistral Dancer in July 2018 and began their sailing adventure, the Times of London reported.

On March 23, they were moored off a small island near George Town in the Bahamas when they heard an “all mighty bang” as a lightning bolt struck the vessel’s mast and destroyed the navigation equipment, according to the outlet.

“I never want to experience anything like that again, at all,” Mike, told the Times of London.

“It’s really scary at the moment because all the other boats are racing back to the US to get out of the hurricane and tropical storm belt and we’re stuck here.”

Mike, who is from Suffolk, said he had never seen an electrical storm quite like it.

“But we’re alive because I’m not sure what would have happened if we had been on deck,” he said.

While insurance is expected to cover most of the $45,000 repair cost, the couple will still have to come up with about $7,500.

Mike, who has had several careers, including as a truck driver, and Helen, who was a midwife, receive only a modest pension and can’t afford even that amount.

In the meantime, they are stuck and are in a race against time before the hurricane season arrives.

The couple set off on a 35-day Atlantic crossing in 2022 and spent the past year island-hopping in the Caribbean, where they moored off the small island of Crab Cay before disaster struck.

“At first I thought someone had crashed into the side of us or something,” Mike said.

“With it was this massive flash of white and blue light that just lit the inside of the boat up. It was like a flashbulb but 100 times brighter and with blue light added to it,” he added.

 A friend and fellow sailor has launched a GoFundMe campaign to help the couple cover their insurance excess and any extra costs, including visa renewals and the cruising permit.

The couple tied the knot after 37 years and three children together, then sailed through the Mediterranean to Turkey and later crossed the Atlantic in 2023, according to the fundraising organizer Tony Wells.

“Their savings have been exhausted preparing the boat for ocean passages — the Pacific was in their sights – and upgrading safety equipment,” he wrote.

As of Friday morning, about $4,500 had been raised in the funding drive.

“Mike and Helen are overwhelmed by everyone’s generosity thus far and would like to say a heartfelt ‘thank you’ to each and every supporter,” Wells wrote.

If they can somehow get their craft repaired in time, they plan to continue to Jamaica and then Colombia.

What comes next for Steven Stamkos and the Lightning?

To commemorate Steven Stamkos’ 1,000th career NHL game, his buddies surprised him with an epic golf trip last summer.

Alex Killorn , Pat Maroon , Victor Hedman , Ryan McDonagh and Corey Perry were among the Tampa Bay Lightning teammates past and present who chipped in to get Stamkos a charter plane and a few rounds at Pine Valley, an exclusive and top-rated course outside Philadelphia.

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“We wanted to show him how much he meant to us,” Killorn said.

The fact that Stamkos reached the milestone as a member of the Lightning was fitting. The 2008 No. 1 pick is the face of the franchise, a two-time Stanley Cup champion and even the voice once used to greet visitors at the Tampa airport.

His place in franchise history is clear. The future, though, is less so.

Stamkos has said he wants to be a lifelong Bolt, but his frustrations over a lack of contract talks last summer and potential unrestricted free agency this summer have become one of the biggest stories bubbling under the surface in the NHL .

Will these upcoming playoffs be the swan song for Stamkos in Tampa Bay?

“I think if he could choose, he would stay,” Killorn said.

But he then added: “Everyone has a certain amount of pride. He’s going to be a Hall of Famer. At a certain point, if they don’t want you, he won’t want to stay.”

Lightning general manager Julien BriseBois has said since the start of the season that he hopes to re-sign his captain — that Stamkos finishing his career with Tampa Bay would be “in everyone’s best interest.” But the longer this goes, the more it seems possible that Stamkos could become the latest and by far biggest cap casualty in the team’s unrelenting quest to keep its Cup window open.

Hard and sometimes harsh decisions have become as common in Tampa as championship boat parades.

Only three days after the season in 2022, Brisebois told McDonagh that the Lightning had no choice but to trade him even though his contract included a no-movement clause. The defenseman was dealt to Nashville a week after skating in a third straight Stanley Cup Final with the Lightning.

Ondrej Palat walked out the door that same summer. One of the organization’s ultimate success stories as a seventh-round pick who became a key contributor on championship teams at both the AHL and NHL levels, he said he would have taken less than the $30 million, five-year deal he ended up signing with the New Jersey Devils to remain with the Lightning. But talks between BriseBois and his agent were brief, according to Palat, and amounted to one lowball offer and no further negotiations.

“I kind of wish it was a (back and forth negotiation), but that made the decision easy,” Palat said.

Killorn, Yanni Gourde and Tyler Johnson were also cap-related departures, helping free space to sign long-term extensions with the core being built behind them — a group that includes Brayden Point , Anthony Cirelli , Brandon Hagel , Nick Paul , Mikhail Sergachev and Erik Cernak .

But Stamkos?

He’s different.

He’s the thread that runs through nearly half of the organization’s existence. The captain who followed Martin St. Louis and Vincent Lecavalier and led the team to the Stanley Cup Final on four occasions. The player who scored one of the most dramatic goals of his generation . The chief of the Lightning’s welcoming committee, opening his door or lending a spare car to any teammate in need. The man who took a quick peek at free agency in 2016 before signing for less in Tampa, helping pave the way for the dominant stretch that followed.

“Absolute great leader,” Gourde said.

“Incredible guy,” Palat said. “Incredible leader and person. I’m glad we’re friends.”

“He’s been one of the biggest reasons for the franchise being in the state it’s in for the last probably 12 years,” Luke Schenn said. “He’s been the leader there. He’s been the voice in the community, in the dressing room, amongst the coaching staff and everything.”

“He’s a legend,” added Victor Hedman. “He’ll forever be a legend in this organization.”

Stamkos is what any organization hopes it’s getting when picking first in the NHL Draft: talented, committed, thoughtful and community-minded.

And productive. He’s scored fewer goals than only Alex Ovechkin and fewer points than only Sidney Crosby , Ovechkin and Patrick Kane since being called to the draft stage by former Lightning owner Oren Koules.

It has been nearly 6,000 days since the Lightning played a game without Stamkos as a member of the organization.

He’s now less than 90 days from hitting the open market.

A couple of weeks before the biggest goal of his NHL career, Stamkos delivered one of his most poignant messages.

On a whiteboard.

It was during the Lightning’s 2020 Cup run, played in the Edmonton bubble due to COVID-19. Stamkos had been dealt several frustrating setbacks in his rehab from a core injury and didn’t know if he’d play in the postseason. Tampa Bay had just lost Game 5 of the Eastern Conference final to the New York Islanders , cutting its series lead to 3-2.

Stamkos was the last player at the rink after practice the day before Game 6. He returned to the arena while his teammates were taking a pregame nap, grabbed one of the coaches’ whiteboards, flipped it over and poured his heart out about how special the group was, how much they meant to him.

“Just do it, boys!”

Many teammates still have a photo of the message on their phones.

“It was one of the most heartfelt messages ever,” Schenn said. “It gives you goosebumps. It gives you chills. We walked in there and everyone was blown away. How can you not win the game after seeing that?”

“It was a special moment in history,” Killorn said. “He wasn’t in the locker room, but we had that.

“Really powerful.”

Killorn, drafted by the Lightning the year before Stamkos went No. 1, remembers their first development camp together. Stamkos was the prodigy featured in “Seen Stamkos?” billboards all over town. He had an aura, even for a teenager. “He was a superstar,” Killorn said.

But not the only one in Tampa when he arrived. Lecavalier was the captain and a Cup champion. St. Louis was a Hart Trophy winner and Cup winner. Today, though, St. Louis believes Stamkos is the best player in franchise history. Probably the most meaningful, too.

Former Lightning winger Ryan Callahan, the ex- Rangers captain, saw the weight Stamkos carries after being acquired in the 2014 trade that sent St. Louis to New York.

“He’s the guy. He’s the man ,” Callahan said. “You think of Tampa and the Cup runs and Cups they won, Stammer is the first player that comes to mind. You think of Tampa, you think of one player. It’s Stamkos.”

Teammates have said that had Stamkos not decided to stay in the summer of 2016, the 2020 and 2021 Cup runs might not have happened. He was the most high-profile NHL free agent in over a decade and had his pick of suitors, including his hometown Toronto Maple Leafs . Friends and family all believed that Stamkos wanted to stay. Owner Jeff Vinik made a personal pitch a couple of nights before free agency and was hopeful, too. But there were doubts, even inside the Lightning offices. Executives were making contingency free-agency plans. That was until then-GM Steve Yzerman popped into then-assistant GM BriseBois’ Amalie Arena office with the bombshell.

“I got a call. Stammer is staying.”

BriseBois said later that the signing “set the tone” for the team’s run of success and that its impact would be measured “for a number of years to come.” Many of Tampa Bay’s top stars followed suit, taking team-friendly deals to build what turned into a multi-championship core.

The circumstances surrounding Stamkos’ free-agent decision in 2016 and what’s coming this summer have changed, of course. Back then, Stamkos wanted to finish what he started and bring a title to Tampa Bay. He’s done that twice, and now the Lightning are fighting Father Time to keep that championship window open.

If anything, though, Stamkos is even more entrenched now. His wife Sandra and their two sons love it in Tampa.

“As you progress and you have a family, your decisions become a little bit different,” Stamkos said. “You have to start thinking about the future a little more. In that regard, it’s a lot different than eight years ago. There’s nothing I can do about it except go out and try to play my best and help our team win.”

When Stamkos came out on the opening day of training camp and voiced his disappointment in the lack of contract talks, it raised eyebrows around the league.

Including former teammates.

Yes, Stamkos was just answering a question in a media day setting. And he was being honest. But for him to go public with that kind of thing — even saying “I can’t write my own contract” — it had friends believing his frustration had boiled over.

“I’d be frustrated as well,” Callahan said. “You give everything you have to an organization, and there’s not even talks. You understand there’s a business side of it as a player. You want that respect of open lines of communication and knowing what’s going on, where the team is at, what their thoughts are, where you should be numbers-wise. I think he’s earned that respect.

“Even if it’s a hard conversation that you might think he might not like, he’s earned the respect to hear it.”

BriseBois said at the start of the season he just needed to see how things played out — how “the pieces of the puzzle fit.” There was uncertainty on the blue line, the entire fourth line had turned over and the team had lost a string of impactful forwards in previous offseasons.

From an organizational perspective, BriseBois wanted to know what his biggest areas of need were before he committed valuable cap space to Stamkos.

“I think it would be great for the organization if Steven could spend his entire career with the Lightning,” BriseBois said in September. “That’s in everyone’s best interest. At the same time, it’s not just about Steven playing out his career in Tampa. It’s about Steven staying in Tampa and the Lightning remaining a legitimate Stanley Cup contender year in and year out for the remainder of his tenure as a player on the club.”

Lightning players have loved that BriseBois will go all-in at trade deadlines and deal first-round picks and assets to give them the best chance to chase the Stanley Cup.

“That’s the thing with Julien,” Killorn said. “We give him a lot of credit because he’s got a lot of balls. He’ll make the trade that people will question. As players, we love it because we want to win. In his mind, he does what he thinks is best for the team, no matter what. That’s his motto.”

But it’s one thing to see the organization put sentimentality aside and make difficult decisions involving teammates. It’s another to experience it first-hand.

And, again, Stamkos is different .

So should he give them pause?

The team may be wise to consider aging curves in evaluating another multi-year deal. His overall five-on-five performance metric-wise has declined, with his 46 percent expected goals rate down from 50 percent last season and 54 percent three seasons ago, per Evolving-Hockey . His goals rate is also down: 42 percent this season, down from 55 percent last season and a little over 60 percent three seasons ago.

On the other hand, he’s still a point-per-game player, with 39 goals this season. He’s a difference-maker and one of the sport’s legendary captains.

And those who have played beside him see a determined future Hall of Famer who has accumulated more than his share of scars and come out better on the other side.

“He goes through all the injuries, the blood clot, meniscus, broken leg,” Killorn said. “He’s kept such a positive attitude. Even in the playoffs when he wasn’t playing, he came in for one game (in the 2020 Final versus Dallas ) and tore his f—ing groin again on that play. The way he’s dealt with injuries is more telling about his career and character than his skill set.”

“He’s still Stammer,” Callahan said.

Stamkos has told everyone, from teammates to reporters, that he wants to finish his career in Tampa Bay. He grew up idolizing Joe Sakic and Steve Yzerman, both Hall of Famers who played their entire careers with one organization.

The idea of Stamkos wearing another sweater?

“That’d be crazy,” Blake Coleman said.

“It’d just seem wrong,” Ross Colton said.

“I can’t imagine it,” Callahan said. “He’s one of those guys that you can’t picture another jersey on him, how much he means to that organization. When you think of Tampa, you think of Stammer wearing the ‘C’ and winning Cups.

“Playing somewhere else? It’s tough to think it’d come to that.”

If Stamkos does get to test free agency, there will be suitors. The Florida Panthers , the Lightning’s in-state rivals, have been known to swing big, and Stamkos would be a huge one. Stamkos would fit in nicely with the Nashville Predators in another lower-key Southeast market, which also happens to feature good friends in Schenn and McDonagh.

“We’ve got cap space in Anaheim, so I’ll be recruiting him if they decide not to re-sign him,” Killorn said.

“If it’s not Tampa, he’ll have a line,” Callahan said. “A lot of teams (will be) lobbying to get him there. It’ll be interesting.”

BriseBois tried to downplay speculation at the trade deadline by declaring a few weeks before that Stamkos would not be moved. He knew it would be a story. Asked in February if he envisioned Stamkos being on the Lightning beyond this summer, BriseBois did acknowledge that, Stamkos being who he is, his stature and history with the organization “obviously factors in.”

“After the season, we’re going to sit down and evaluate where we are as a team, where Steven is, and see how we can make all those parts come together,” BriseBois said.

What makes the situation fascinating is that if Tampa Bay goes deeper in the playoffs, it may make more of an argument to keep Stamkos. If it becomes a second straight one-and-done postseason, the Lightning may be facing an unthinkable decision.

“Whatever happens, he’ll have his jersey up in the rafters when it’s all said and done,” Callahan said. “His mark will be on Tampa. I’m not worried about that. There will be a trip to Toronto for the Hall of Fame. And there will be a statue next to (Dave) Andreychuk. It’s impressive what he’s done.”

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(Graphic by Dan Goldfarb / The Athletic , with photos from Mark LoMoglio, Mike Carlson and Bruce Bennett / Getty Images)

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