Those who were involved in the recent discussion of whether or not to
bond hull fittings to a central plate (I believe many said yes) or to
the engine block (almost everyone said no) will be interested in an
article in the September issue of Practical Boat Owner. The author and
his wife were motor-sailing in an English inlet just north of the Thames
estuary when a major squall hit quickly, and they witnessed three
lightning strikes: they saw the first two which were very close to the
boat, but not the third which was a direct strike on the mast.

The damage was significant and in several ways, surprising, ranging from
having to replace everything at the top of the mast and the standing
rigging, much of the inside electronics and all deck electrics, the
batteries, alternator, oil plug light core, keel bolts, some chain plate
bolts, zincs, and even the prop shaft. The electronics in his 35 mm
camera and cell phone were also fried.

He makes several observations:

1. it happens so fast there's nothing you can do;
2. don't touch any metal when there's lightning around. His wife was
   sitting on the foredeck between two winches, and the charge arced -
   apparently right through her - but because she wasn't grounded, although
   knocked unconscious she recovered quickly and sustained no lasting
   injuries. He was unhurt, standing over the wooden tiller a "few inches
   of fresh air" from the backstay to the steel rudder head.
3. the diesel engine had a flash mark down one side where the copper
   fuel pipes are located. His surveyor assured him that a gasoline engine
   "would have exploded".
4. re my opening para, "I'm glad I resisted bonding all the skin
   fittings to the engine or to a single grounding plate. I'm convinced
   that had I done that we'd have lost several fittings and the ground
   plate - and frankly, that we'd have sunk".
5. if it happens, get the boat re-surveyed very carefully to claim
   properly on insurance. The damage to the prop shaft was discovered only
   1o months later.

One more safety comment: his VHF radio and phone were both knocked out,
the latter because he kept it in a charger. As a result, he had no way
to send a distress signal. He notes that no one could possibly have seen
a flare in the weather conditions they were experiencing. A hand-held
VHF, not in a charger, could well have saved their lives had they had to
abandon a sinking vessel.

Cheers, Garrett

Many years ago I spent summers on a fire lookout for the U.S,
Forest Service.The fire lookout was very well grounded with a
lightning rod at the peak and four copper wires about the size of
your finger running in the four directions to the ground. All metal in
the building was grounded, including the bed and wood stove.

The instructions for lightning were in a frame screwed to the fire-
finder.  A few things I remember they said are:

When strikes were expected, close all the doors and windows
because lightening follows air currents.

Disconnect the old SCR 610 radio antenna.

Stand on the little stool in the middle of the lookout opposite the
stove.  (The stool was about 12"x 18" square with 6"legs and old
glass telephone insulators screwed to the bottom of the legs.

Mark lightening strikes on the fire-finder map. After the storm has
passed report all information gathered to the ranger station.

It worked time and time again for me. Scared?  You bet.  Literally
hair raising almost every time.

I disagree that there is nothing you can do to help your survival on
a trawler.

Recognize cumulus/nimbus clouds and their potential.
Disconnect the radio's and other electronics, especially the
antennas.  Shut the doors and windows. Stay away from larger
metal objects. Try to insulate yourself and others from anything
else on the boat.(the glass stool trick).  (Standing on your spare
rolled up rubber garden hose could be one way.)  Expect gusty
winds. Recite the fire lookout's prayer....a lot of the content has to
do with bargaining with your maker on what you'll do and how you'll
change your ways if you survive.

Sandy Floe
Sea Eagle (39 CHB)
Day Island, WA