[Rhodes22-list] sailing and lightning

[DCLewis1 at aol.com]

Bill,
 
FWIW, years ago my car was struck by lightning while sitting in  a virtually 
empty parking lot.  I didn't see it, but I was working  late and one of the 
night staff came running in to tell me he'd seen my car hit  by lightning.  As I 
recall, there were tall metal lighting poles  stationed around the lot (the 
lot was lit), but the stroke found my car.   I was told it was a direct hit to 
the engine hood.  For the most part  the wires in the engine compartment were 
fried, not just blown but insulation  melted and there was evidence of a fire 
(a lot of black soot on the engine  hood and the whole car and the area around 
it smelled like burnt  insulation), but the car survived with new wiring.   
And not, I'm  not grounding my car as the result of that experience.
 
Re chains on tanker trucks, I think I've seen some recently, I may be  wrong. 
 But I don't think that's about lightning protection, I think that's  to 
mitigate static discharge.
 
Seems to me that the first line of defense with lightning is to avoid  it.  
Also, I suspect the direct path to ground would be along the lee outer  shroud, 
or a bow or back stay, not the mast.  If you lost one  shroud/stay, it might 
not be the end of the world given the R22s  redundancy.  But I could be wrong.
 
In following this thread it looks like there are 2 trains of thought:
1. Don't do anything to encourage a lightning strike.
2. Arrange things so that when lightning does strike the current  is guided 
safely off-board.
 
The problem with #2 is that as commonly implemented it should actually  
encourage strikes - which you don't want unless you are very-very-very sure your  
protection scheme works. (Note: Actually, even if the protection system  does 
work and guides the strike current safely off-board, the radiated EMP  from the 
pulse transmitted down the shroud/stay/or mast to ground should blow  out the 
front end of your radio, GPS, etc.)
 
I gather there have been much more than 1,000 R22s sailing around or docked  
for decades with no known lightning strike problems (correct me if I'm  
wrong).  Some few of them might have lightning protection systems  installed, but 
I'd bet approach #1 applies for most of the fleet.  Seems to  me that until 
someone reports a problem a fix isn't warranted, or that the  best fix might be 
#1, avoid lightning.  I could be wrong.
 
Dave