Besides running the autopilot during an electrical storm (which may get fried if a lightning strike is sustained), what techniques of handling the wheel are useful while reducing the risk of ME getting fried from a strike? I will cherish all answers!
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Walt Golembewski
Jumper Cables #2
I carry a set of battery jumper cables aboard, which I have separated into separate leads. I connect one cable to the rear shroud and one to a side shroud, and trail both overboard during electrical storms. This, I have been told, serves to bleed the electrical charge gathered by the mast and rigging to ground, reducing the chance that the charge will get large enough to cause a lightning strike. And even if you are unfortunate enough to get hit, the cables should provide a path of low resistance to ground, so the hit has a better chance of going through the cable instead of through you. I also wear rubber boots and use gloves -- either diver's gear or storm gear. I have used this technique during at least 4 violent storms that I have been caught in. Maybe I have just been lucky, but I haven't been hit yet, even though there were air-to-water strikes within several hundred yards in one case. And you can still use the jumper cables for the purpose they were originally designed for.
I carry a set of battery jumper cables aboard, which I have separated into separate leads. I connect one cable to the rear shroud and one to a side shroud, and trail both overboard during electrical storms. This, I have been told, serves to bleed the electrical charge gathered by the mast and rigging to ground, reducing the chance that the charge will get large enough to cause a lightning strike. And even if you are unfortunate enough to get hit, the cables should provide a path of low resistance to ground, so the hit has a better chance of going through the cable instead of through you. I also wear rubber boots and use gloves -- either diver's gear or storm gear. I have used this technique during at least 4 violent storms that I have been caught in. Maybe I have just been lucky, but I haven't been hit yet, even though there were air-to-water strikes within several hundred yards in one case. And you can still use the jumper cables for the purpose they were originally designed for.
S
Scott Broad-
Hope this helps
It was in August of 1999, while crossing Lake Ontario. Approximately 5 miles from shore, aboard our brand new Hunter 310 –“Edit Sweet”. We took a flash of lightning. Not a direct hit luckily, but still enough to blow me off the helm and burn skin on my feet. Since then, I have had a keen interest in lightning, and the dynamic principles it contains. I have put together a little information for you that you may find helpful. The odds in 1990 of being struck by lightning were about 1:2,850,000 with1:28,500 being your risk of being killed by lightning. They say the best protection from lightning is avoiding the storm. This can however, often be unavoidable. NOAA reports that the average thunderstorm travels at 25 miles per hour, with the average lightning stroke being 6 miles long. Once the leading edge of a thunderstorm approaches to within 10 miles, you are at immediate risk due to the possibility of lightning strokes coming from overhanging anvil clouds. Because of this, many lightning deaths and injuries occur with clear skies directly overhead. In our case, using the above statistics, we would had to have been docked 1 hour before we left Toronto. The best protection is avoiding storms, but next best is grounding the masts on sailboats with copper wire connected to conductors in the water. Conductors can be a 1-foot metal plate for saltwater boats, but should be at least a long metal strip along the bottom of the hull for boats in fresh water. Sailors should also ground the wire to other metal conductors in the water, such as the prop. Negative charges repel negative charges and attract positive charges. So, as a thundercloud passes overhead, a concentration of positive charges accumulates in and on all objects below the cloud. Since these positive charges are attempting to reach the negative charge of the cloud, they tend to accumulate at the top of the highest object around. The better the contact an object has with the water, the more easily these positive charges can enter the object and race upward toward the negative. Lightning strikes represent a flow of current from negative to positive, and when the lightning does strike, it will most often strike the highest object in the immediate area. If it strikes the boat, the electrical charge is going to take the most direct route to the water where the electrical charge will dissipate in all directions. Your body may then become the best conductor for the electrical charge. In the example of a sailboat. Lightning strikes the mast. The electrical current follows the mast or wire rope to your hands, through your body to the wet surface, and then through the hull to the water. Small boats are seldom made of metal. Their wood and fiberglass construction do not provide the automatic grounding protection offered by large metal-hulled ships. Therefore, when lightning strikes a small boat, the electrical current is searching any route to ground and will use your body as a conductor of electricity! These boats can be protected from lightning strikes by properly designed and connected systems of lightning protection. Lightning protection systems do not prevent lightning strikes. In fact, there is an increasing argument that they may actually increase the possibilities of the boat being struck. The purpose of lightning protection is to reduce the damage to the boat and the possibility of injuries or death to the passengers from a lightning strike. The National Fire Protection Association, Lightning Protection Code, suggests a number of ways in which the boater can protect his boat and minimize damage if the boat is struck or is in the vicinity of a lightning strike. These suggestions are summarized below: A lightning protective mast will generally divert a direct lightning strike within a cone-shaped radius two times the height of the mast. Therefore, the mast must be of sufficient height to place all parts of the boat within this cone-shaped zone of protection (see Figure 6). The path from the top of the mast to the "water" ground should be essentially straight. Any bends in the conductor should have a minimum radius of eight inches. To provide adequate protection, the entire circuit from the top of the mast to the "water" ground should have a minimum conductivity equivalent to a No. 8 AWG copper conductor. If a copper cable is used, the individual strands should be no less than No. 17 AWG. Copper metal or strips should be a minimum of No. 20 AWG. Major metal components aboard the boat, within six feet of the lightning conductor, should be interconnected with the lightning protective system with a conductor at least equal to No. 8 AWG copper. It is preferable to ground the engine directly to the ground plate rather than to an intermediate point in the lightning protection system. If the boat's mast is not of a lightning protective design, the associated lightning or grounding connector should be essentially straight, securely fastened to the mast, extended at least 6 inches above the mast and terminate in a sharp receiving point. The "water" ground connection may be any submerged metal surface with an area of at least one square foot. Metallic propellers, rudders or hull will be adequate. On sailboats, all masts, shrouds, stays, preventors, sail tracks and continuous metallic tracks on the mast or boom should be interconnected (bonded) and grounded. When caught in a storm: 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 be a "stand-up human" lightning mast! Keep arms and legs in the boat. Do not dangle them in the water. Disconnect and do not use or touch the major electronic equipment, including the radio, throughout the duration of the storm. To the degree possible, avoid making contact with any portion of the boat connected to the lightning protection system. Never be in contact with two components connected to the system at the same time. Example: The gear levers and spotlight handle are both connected to the system. Should you have a hand on both when lightning strikes, the possibility of electrical current passing through your body from hand to hand is great. The path of the electrical current would be directly through your heart--a very deadly path! It would be desirable to have individuals aboard who are competent in cardiopulmonary resuscitation (CPR) and first aid. Many individuals struck by lightning or exposed to excessive electrical current can be saved with prompt and proper artificial respiration and/or CPR. If a boat has been, or is suspected of having been, struck by lightning, check out the electrical system and the compasses to insure that no damage has occurred. (More info - see Lightning Safety Tips. Please pass this around.)
It was in August of 1999, while crossing Lake Ontario. Approximately 5 miles from shore, aboard our brand new Hunter 310 –“Edit Sweet”. We took a flash of lightning. Not a direct hit luckily, but still enough to blow me off the helm and burn skin on my feet. Since then, I have had a keen interest in lightning, and the dynamic principles it contains. I have put together a little information for you that you may find helpful. The odds in 1990 of being struck by lightning were about 1:2,850,000 with1:28,500 being your risk of being killed by lightning. They say the best protection from lightning is avoiding the storm. This can however, often be unavoidable. NOAA reports that the average thunderstorm travels at 25 miles per hour, with the average lightning stroke being 6 miles long. Once the leading edge of a thunderstorm approaches to within 10 miles, you are at immediate risk due to the possibility of lightning strokes coming from overhanging anvil clouds. Because of this, many lightning deaths and injuries occur with clear skies directly overhead. In our case, using the above statistics, we would had to have been docked 1 hour before we left Toronto. The best protection is avoiding storms, but next best is grounding the masts on sailboats with copper wire connected to conductors in the water. Conductors can be a 1-foot metal plate for saltwater boats, but should be at least a long metal strip along the bottom of the hull for boats in fresh water. Sailors should also ground the wire to other metal conductors in the water, such as the prop. Negative charges repel negative charges and attract positive charges. So, as a thundercloud passes overhead, a concentration of positive charges accumulates in and on all objects below the cloud. Since these positive charges are attempting to reach the negative charge of the cloud, they tend to accumulate at the top of the highest object around. The better the contact an object has with the water, the more easily these positive charges can enter the object and race upward toward the negative. Lightning strikes represent a flow of current from negative to positive, and when the lightning does strike, it will most often strike the highest object in the immediate area. If it strikes the boat, the electrical charge is going to take the most direct route to the water where the electrical charge will dissipate in all directions. Your body may then become the best conductor for the electrical charge. In the example of a sailboat. Lightning strikes the mast. The electrical current follows the mast or wire rope to your hands, through your body to the wet surface, and then through the hull to the water. Small boats are seldom made of metal. Their wood and fiberglass construction do not provide the automatic grounding protection offered by large metal-hulled ships. Therefore, when lightning strikes a small boat, the electrical current is searching any route to ground and will use your body as a conductor of electricity! These boats can be protected from lightning strikes by properly designed and connected systems of lightning protection. Lightning protection systems do not prevent lightning strikes. In fact, there is an increasing argument that they may actually increase the possibilities of the boat being struck. The purpose of lightning protection is to reduce the damage to the boat and the possibility of injuries or death to the passengers from a lightning strike. The National Fire Protection Association, Lightning Protection Code, suggests a number of ways in which the boater can protect his boat and minimize damage if the boat is struck or is in the vicinity of a lightning strike. These suggestions are summarized below: A lightning protective mast will generally divert a direct lightning strike within a cone-shaped radius two times the height of the mast. Therefore, the mast must be of sufficient height to place all parts of the boat within this cone-shaped zone of protection (see Figure 6). The path from the top of the mast to the "water" ground should be essentially straight. Any bends in the conductor should have a minimum radius of eight inches. To provide adequate protection, the entire circuit from the top of the mast to the "water" ground should have a minimum conductivity equivalent to a No. 8 AWG copper conductor. If a copper cable is used, the individual strands should be no less than No. 17 AWG. Copper metal or strips should be a minimum of No. 20 AWG. Major metal components aboard the boat, within six feet of the lightning conductor, should be interconnected with the lightning protective system with a conductor at least equal to No. 8 AWG copper. It is preferable to ground the engine directly to the ground plate rather than to an intermediate point in the lightning protection system. If the boat's mast is not of a lightning protective design, the associated lightning or grounding connector should be essentially straight, securely fastened to the mast, extended at least 6 inches above the mast and terminate in a sharp receiving point. The "water" ground connection may be any submerged metal surface with an area of at least one square foot. Metallic propellers, rudders or hull will be adequate. On sailboats, all masts, shrouds, stays, preventors, sail tracks and continuous metallic tracks on the mast or boom should be interconnected (bonded) and grounded. When caught in a storm: 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 be a "stand-up human" lightning mast! Keep arms and legs in the boat. Do not dangle them in the water. Disconnect and do not use or touch the major electronic equipment, including the radio, throughout the duration of the storm. To the degree possible, avoid making contact with any portion of the boat connected to the lightning protection system. Never be in contact with two components connected to the system at the same time. Example: The gear levers and spotlight handle are both connected to the system. Should you have a hand on both when lightning strikes, the possibility of electrical current passing through your body from hand to hand is great. The path of the electrical current would be directly through your heart--a very deadly path! It would be desirable to have individuals aboard who are competent in cardiopulmonary resuscitation (CPR) and first aid. Many individuals struck by lightning or exposed to excessive electrical current can be saved with prompt and proper artificial respiration and/or CPR. If a boat has been, or is suspected of having been, struck by lightning, check out the electrical system and the compasses to insure that no damage has occurred. (More info - see Lightning Safety Tips. Please pass this around.)
S
Scott B.
Does This Work?
Let's suppose I cant find someone with a 70' mast to dock next to, and dont have all the systems in place that Scott Broad suggests, is there a temporary system that would work?? For example, what if I clipped a No. 8 AWG copper conducter to the mast, put a plate on the other end, draped it over the side of the boat, and threw it in the water. This would obviously work best if docked. Will this work, or do the Hunter 31's already have a grounding system installed for lightning.
Let's suppose I cant find someone with a 70' mast to dock next to, and dont have all the systems in place that Scott Broad suggests, is there a temporary system that would work?? For example, what if I clipped a No. 8 AWG copper conducter to the mast, put a plate on the other end, draped it over the side of the boat, and threw it in the water. This would obviously work best if docked. Will this work, or do the Hunter 31's already have a grounding system installed for lightning.
J
John
Conductor Location
The answer that Scott Broad gave is really good and if followed should provide the best protection. The question about attaching a conductor to the mast and throwing the other end overboard with a plate will probably not work if the attach point is near the deck. The conductors to transmit the charge to the ground/water should be placed on the furtherest most/outside of what you're trying to protect. In the case of a sailboat the shrouds are going to be the the furtherest outside of what you're trying to protect. I'd suggest clamping a connector to the stay (copper clamp with screw preferable to squeeze clamp like a battery clip) and then put the plate overboard. Since your boat has a backstay I'd do this for the forestay, backstay, and each shroud. This will give you the beginning of a cone of protection. Since you live in Idaho, go to a Forest Service fire lookout (if there are still some that haven't been replaced by a satellite!) and see how they do their protection. Each ridge of the "cab" roof has a heavy solid copper conduter and it travels down each corner and eventually to ground. Inside the cab everthing is grounded, including the table. Anything less than this, or like what Scott described, will provide less than perfect protection. Only connect to the ground grid what you want protected.
The answer that Scott Broad gave is really good and if followed should provide the best protection. The question about attaching a conductor to the mast and throwing the other end overboard with a plate will probably not work if the attach point is near the deck. The conductors to transmit the charge to the ground/water should be placed on the furtherest most/outside of what you're trying to protect. In the case of a sailboat the shrouds are going to be the the furtherest outside of what you're trying to protect. I'd suggest clamping a connector to the stay (copper clamp with screw preferable to squeeze clamp like a battery clip) and then put the plate overboard. Since your boat has a backstay I'd do this for the forestay, backstay, and each shroud. This will give you the beginning of a cone of protection. Since you live in Idaho, go to a Forest Service fire lookout (if there are still some that haven't been replaced by a satellite!) and see how they do their protection. Each ridge of the "cab" roof has a heavy solid copper conduter and it travels down each corner and eventually to ground. Inside the cab everthing is grounded, including the table. Anything less than this, or like what Scott described, will provide less than perfect protection. Only connect to the ground grid what you want protected.
M
Mark Kissel
What's really important...
...is that you provide a solid path to ground (water). Since the mast, stays, and shrouds are metal, AND all connected together, a strike to the mast will elevate the electric potential difference of the entire rig. That means base of mast, tip of mast, middle of mast, shrouds, spreaders, etc. Most of that energy will flow along the surface of the metal via a phenomenon know as the "skin" effect. Regardless of where you attach the ground, if you touch any metal common to the strike point, your life could be in jeopardy. Grounding the rig will NOT protect your electronics. The intense fields generated by the current flow in a strike will inductively couple with the wiring to these devices and cause damage. If possible, unplug them and disconnect any long thin wires that may be attached such as antenna cable or sending unit wires. I realize this is not practical in most circumstances so carry that lucky charm just in case. Mark Kissel Kittiwake/H240
...is that you provide a solid path to ground (water). Since the mast, stays, and shrouds are metal, AND all connected together, a strike to the mast will elevate the electric potential difference of the entire rig. That means base of mast, tip of mast, middle of mast, shrouds, spreaders, etc. Most of that energy will flow along the surface of the metal via a phenomenon know as the "skin" effect. Regardless of where you attach the ground, if you touch any metal common to the strike point, your life could be in jeopardy. Grounding the rig will NOT protect your electronics. The intense fields generated by the current flow in a strike will inductively couple with the wiring to these devices and cause damage. If possible, unplug them and disconnect any long thin wires that may be attached such as antenna cable or sending unit wires. I realize this is not practical in most circumstances so carry that lucky charm just in case. Mark Kissel Kittiwake/H240
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