It is really very unusual for boats to be struck while actually sailing. The reason for this appears to be that the motion of the boat through the water
and the mast
through the air dissipates charge, such that a big ground charge cannot effectively gather. Most strikes happen in Marinas
or at anchor
for exactly this reason. They can be devastating. A few years ago a big superyacht ketch
burnt to the waterline in Falmouth Antigua
following a lightning strike. The strategy I recommend is twofold: attempt to dissipate static charge in your rig, which "attracts" a strike, and is the precursor to one. You can try attaching a dissipator to the masthead which is basically a brush of extremely fine steel
filaments, which are supposed to aid charge dissipation. This is fairly conventional and has a good rationale for success. Rather more unconventional is the arrangement I carry aboard my own boat. In Scotland
a decade or so ago I had it made by a lightning protection company specialising in buildings. It is a grounding surface comprised of around 70cm grid of thick copper stips riveted together in a lattice and bonded to a massive cable which has an equally massive alligator clip at the other end. If anchored or in a marina during an electrical storm, I dangle the thing over the side into the water
, hung by a lanyard from the rails, and clip the cable to a cap shroud
. The idea is of course that in the case of a strike the charge would be encouraged to take out or take the route
of said single shroud
, and not pass through the boat. So far I have not been struck (searches for wood to knock), and not for lack of storms!
The oven faraday cage is sensible SOP for electrical storms and boats.