lightning strikes
Recently, we experienced a rash of lightning strikes in our marina, and several boats were struck, including the boat I run, Brier Patch. Interestingly, we did not even take a direct hit; the lightning hit another 72-foot Merritt docked next to us. The bolt struck an antenna, blowing it apart and sending burned shards and pieces of fiberglass flying in a 100-yard radius around the boat, including all over Brier Patch and the parking lot.
Lightning can enter your boat several ways. It can make a direct hit through something elevated and conductive, such as an antenna, a tower or other metal, or the current can jump through the water, through your shore power cord or from one boat to the next.
Most damage comes from overcurrent that’s transmitted through the wiring and then terminated at the end of the wire at a piece of equipment. Lightning strikes nearby can also generate electromagnetic pulses that can affect all of your boat’s electronic equipment.
With our neighbor taking the direct hit and no visible signs of damage to our antennas or tower, it soon became obvious that we took our hit through the water. The damage to the other vessel was immediate: Engine ECUs, navigational equipment, entertainment equipment and other systems were nonoperational and obviously damaged. After the strike, the process of starting up gear and determining what was bad took time, and our tests revealed that most electronic systems had some sort of failure or another.
Our problems didn’t show themselves immediately. We saw some signs of the strike from our electronics monitors and some circuit boards, but it took some time for most of the electrical gremlins to start popping up, and once they did, they did so with a vengeance.
It ended up being the case that most of our navigation and echo-sounding equipment had some problem or another, if the units were not completely toasted. The watermaker control boards were blown, a couple of pumps were fried, and we had plenty of other problems on miscellaneous gear. Luckily, our engine and generator electronics seemed to have weathered the strike just fine. The interesting thing was that it took several weeks, even a month, for some of these issues to show up. Several electronics experts I have spoken to say that this is common.
Lightning strikes create huge problems on today’s boats due to all the integrated systems, black boxes and fly-by-wire technology. Back in the day, main engines were mechanical and did not have the sophisticated computerized control systems, electronic fuel systems and the like. Electronics were stand-alone units that were isolated, so when there was a failure, you would usually only lose one element. Nowadays, with all of our multifunction equipment, your navigation, radar and echo-sounder capabilities can be wiped out in one shot. I’m not saying that stand-alone units could survive a lightning strike, but there is a chance that only some of your system would be affected if its components were all housed separately.
Fort Lauderdale insurance survey specialist Stewart Hutchinson, of Harbor and Ocean Services Inc., does all of our survey work, and he worked closely with our electronics gurus — Commercial Marine Electronics of Pompano Beach and Don Sloss, the ace boat electrician at Merritt — to get the boat back in shape. Having seen his fair share of lightning strikes and the many aftermath scenarios, Hutchinson offered some excellent tips on what to do after a strike, and how to be certain that everything is shipshape after the event and the fix-up. He also told us about several ways that we could limit the damage from any future strikes.
After a strike, there are several things that you need to do right away to prevent further damage and make certain that the boat and all systems are stable. First, call your insurance agent and make certain that your insurance company is aware of the situation. An insurance surveyor needs to get out to your boat immediately so that you can document what has been affected, and to what extent things will need to be replaced. The surveyor typically does this with your electronics technician and the boatyard personnel familiar with the systems aboard your boat.
Secondly, before you do anything on the boat, disconnect the shore power cord, shut off all your breakers, and do a complete visual inspection of the boat so that you know you’re not taking on water due to any underwater damage caused by the hit. Do not do any cleanup and do not remove anything until you have met with your surveyor, as you may destroy evidence needed to substantiate your claim. In some instances, you may also want to disconnect the batteries, except for those powering the bilge pumps. However, you have to confirm that the bilge pumps and float switches actually work, since they too may have been affected.
Once the surveyor inspects the boat, he and the electronics technicians, mechanics and boatyard personnel should go through the boat and begin the process of bringing equipment and systems online. By going through this comprehensive process, you can isolate and identify what areas of the boat and what items are affected at that time. This also gives you and your insurance agent a confirmed record of what failed, what gear may have some inconsistencies and, moving forward, what needs to be replaced or repaired.
One of the huge fallacies of a lightning strike is that all the wiring on the boat must be replaced; this is complete nonsense, and you are being taken for a ride if someone suggests it. However, the current generated by a lightning strike seeks the path of least resistance, and it has a very fast and powerful rise time, meaning that the conductors, or in this case the wires, will have a skin effect, which allows a good deal of the current to actually travel through the outer surface or coating of the wire. This makes damage readily visible on most wires.
As far as preventing a strike, there is little you can do. Turning off as much equipment on the boat as you can is a good start. Isolating different electronic systems and how they are fed can also help. Try to keep navigation electronics on their own bus, and pumps, watermakers and other equipment on their own as well. When storing the boat for an extended period of time, lay the antennas down and remove the outriggers; this not only reduces your vertical profile, it helps to preserve and protect those items, since they will be stored out of the elements.
Certainly, it helps to make sure the boat has a good ground. Inserting a rod into the ground and affixing a heavy chain to the rod and around a shaft helps to ground the boat. There have been many instances where a boat struck on the hardtop gets a hole blown in the bottom when the strike travels through the boat and exits.
Lightning strikes are not to be taken lightly, and they can be incredibly expensive. Be sure you have a comprehensive insurance policy with a reputable underwriter, and make sure that the policy specifically addresses lightning strikes and how they will be handled when it comes time to make a claim. Know ahead of time what is and what is not covered and what percentage or amount of deductible you are responsible for.
