lightning - SailNet Community

   Search Sailnet:

 forums  store  


Quick Menu
Forums           
Articles          
Galleries        
Boat Reviews  
Classifieds     
Search SailNet 
Boat Search (new)

Shop the
SailNet Store
Anchor Locker
Boatbuilding & Repair
Charts
Clothing
Electrical
Electronics
Engine
Hatches and Portlights
Interior And Galley
Maintenance
Marine Electronics
Navigation
Other Items
Plumbing and Pumps
Rigging
Safety
Sailing Hardware
Trailer & Watersports
Clearance Items

Advertise Here






Go Back   SailNet Community > Out There > herSailNet
 Not a Member? 


Reply
 
LinkBack Thread Tools
  #1  
Old 06-23-2005
Junior Member
 
Join Date: Jun 2005
Posts: 1
Thanks: 0
Thanked 0 Times in 0 Posts
Rep Power: 0
frankbarbehenn is on a distinguished road
lightning

I read that there are conflicting views about how to deal with lightning: to protect and ground to water or not. It seems to me that there must have been some real physics research on this question since it is so important for sailors. Does anyone know where to look for a real scientific answer???
Reply With Quote Share with Facebook
  #2  
Old 06-24-2005
Senior Member
 
Join Date: Dec 2002
Posts: 552
Thanks: 0
Thanked 0 Times in 0 Posts
Rep Power: 12
GordMay is on a distinguished road
lightning

Some excellent on-line resources on ‘Lightning & Boats’ - Goto:
http://CruisersForum.com - Power Equipment & Electricity - Lightning Information
http://cruisersforum.com/showthread.php?s=&postid=10366#post10366
including:
“Lightning And Sailboats” - by Ewen M Thomson, Univ. Fla. 1992. Sea Grant Publication
[size]The best basic lightning primer for boaters[/size]
http://www.thomson.ece.ufl.edu/lightning/
and more
HTH,
Gord May
Reply With Quote Share with Facebook
  #3  
Old 08-27-2006
Junior Member
 
Join Date: Nov 2001
Location: Pacific Northwest
Posts: 22
Thanks: 0
Thanked 0 Times in 0 Posts
Rep Power: 0
tondelayo29 is on a distinguished road
I just read a great article this morning but it is far to large (20,000 characters) to post here.... It is from
Bruce A. Kaiser
President
Lightning Master Corporation
09/26/90
Reply With Quote Share with Facebook
  #4  
Old 08-27-2006
Junior Member
 
Join Date: Apr 2006
Posts: 24
Thanks: 0
Thanked 0 Times in 0 Posts
Rep Power: 0
sailphoto is on a distinguished road
Lightning scares the bejeebes out of me and I have spent many nights anchored out among other boats hoping that if lightning strikes it would find the radio tower across the harbor or a taller mast ( without any ill will towards others) on a grounded boat around me more attractive than my own. When I first bought my boat which is a 1980 Dockrell 27 cutter and read the survey it revealed that my little ship is not grounded and this prompted me to do a little research on the matter. What I found out after exhausting the resources on the web is the following: In rough numbers a boat that is grounded is twice as likely to be hit by lightning than one that isn't. On the flip side, a boat that isn't grounded and is hit by lighning is twice as likely to catastrophic damage i.e. have a hole blown in the hull and sink and/or kill the crew. None of the sites I visited gave me any absolute statistics except for the ones selling products which in my sceptical way always assume are skewed. It seems also that grounding a boat doesn't provide absolute protection to the crew, especially on smaller boats where you cannot physically get away from the path the lightning wants to take to the ground, down the mast and out through the grounding cable and line.
I don't really love any of these odds. What I have done to date is not ground my boat and to further reduce the likelyhood of being struck I have installed a stainless brush at the mast top designed to "bleed off" negative ions thereby reducing the potential of the boat. Experts disagree as to the effectiveness of this system. As I write this though I am again wondering if I shouldn't ground my boat. The following link discusses the brush system in greater detail http://www.oceanpix.co.uk/Seamanship...g-at-sea-2.htm
Reply With Quote Share with Facebook
  #5  
Old 08-27-2006
sailingdog's Avatar
Telstar 28
 
Join Date: Mar 2006
Location: New England
Posts: 43,291
Thanks: 0
Thanked 9 Times in 9 Posts
Rep Power: 13
sailingdog is just really nice sailingdog is just really nice sailingdog is just really nice sailingdog is just really nice sailingdog is just really nice
Sailphoto-

If I understand the theory behind the lightning dissipators, then the boat needs to be grounded for them to work. Adding one to a boat that is not properly grounded does nothing. The brush can not bleed off the massive static charge potential if it is not ground.
__________________
Sailingdog

To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.

Telstar 28
New England

You know what the first rule of sailing is? ...Love. You can learn all the math in the 'verse, but you take
a boat to the sea you don't love, she'll shake you off just as sure as the turning of the worlds. Love keeps
her going when she oughta fall down, tells you she's hurting 'fore she keens. Makes her a home.

—Cpt. Mal Reynolds, Serenity (edited)

If you're new to the Sailnet Forums... please read this
To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.
.

Still—DON'T READ THAT POST AGAIN.
Reply With Quote Share with Facebook
  #6  
Old 08-28-2006
Cruisingdad's Avatar
Best Looking MALE Mod
 
Join Date: Jul 2006
Location: Mobile Liveaboards
Posts: 9,894
Thanks: 3
Thanked 97 Times in 52 Posts
Rep Power: 10
Cruisingdad is a jewel in the rough Cruisingdad is a jewel in the rough Cruisingdad is a jewel in the rough
Photo, et all,

I believe SD is right. Not going to help a lot with the dissipator if the boat is not grounded.

My personal opinion (AND IT IS A PERSONAL OPINION): If you are primarily coastal and do NOT need a SSB, do NOT ground.

If you either want an SSB or are going to be doing a fair amount of offshore: Ground the crap out of the boat and put a dissipator on top.

Either way, you take your chances... but you also take your chances everytime you hop in your car and get on the highway. Do your best, then don't let it consume you (no pun intended).
Reply With Quote Share with Facebook
  #7  
Old 08-28-2006
sailingdog's Avatar
Telstar 28
 
Join Date: Mar 2006
Location: New England
Posts: 43,291
Thanks: 0
Thanked 9 Times in 9 Posts
Rep Power: 13
sailingdog is just really nice sailingdog is just really nice sailingdog is just really nice sailingdog is just really nice sailingdog is just really nice
I'd second CruisingDad's recommendation to not ground if primarily coastal or inland, and ground well if going offshore or need an SSB. BTW, why would you have an SSB if you're not going offshore???

BTW, I'll take my chances with sailing...far fewer idiots out on the ocean than on the local streets.
__________________
Sailingdog

To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.

Telstar 28
New England

You know what the first rule of sailing is? ...Love. You can learn all the math in the 'verse, but you take
a boat to the sea you don't love, she'll shake you off just as sure as the turning of the worlds. Love keeps
her going when she oughta fall down, tells you she's hurting 'fore she keens. Makes her a home.

—Cpt. Mal Reynolds, Serenity (edited)

If you're new to the Sailnet Forums... please read this
To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.
.

Still—DON'T READ THAT POST AGAIN.
Reply With Quote Share with Facebook
  #8  
Old 08-28-2006
Junior Member
 
Join Date: Apr 2006
Posts: 24
Thanks: 0
Thanked 0 Times in 0 Posts
Rep Power: 0
sailphoto is on a distinguished road
Quote:
Originally Posted by sailingdog
Sailphoto-

If I understand the theory behind the lightning dissipators, then the boat needs to be grounded for them to work. Adding one to a boat that is not properly grounded does nothing. The brush can not bleed off the massive static charge potential if it is not ground.
The problem with using an ionic dissipator on a grounded boat is that you then are trying to disipate the negative charge of the entire ocean through this little stainless steel brush. It just isn't going to be able to do it.
Reply With Quote Share with Facebook
  #9  
Old 08-28-2006
Cruisingdad's Avatar
Best Looking MALE Mod
 
Join Date: Jul 2006
Location: Mobile Liveaboards
Posts: 9,894
Thanks: 3
Thanked 97 Times in 52 Posts
Rep Power: 10
Cruisingdad is a jewel in the rough Cruisingdad is a jewel in the rough Cruisingdad is a jewel in the rough
Photo,

Buy a bigger brush... HAHA!! Just kidding.
Reply With Quote Share with Facebook
  #10  
Old 08-28-2006
sailingdog's Avatar
Telstar 28
 
Join Date: Mar 2006
Location: New England
Posts: 43,291
Thanks: 0
Thanked 9 Times in 9 Posts
Rep Power: 13
sailingdog is just really nice sailingdog is just really nice sailingdog is just really nice sailingdog is just really nice sailingdog is just really nice
Quote:
Originally Posted by sailphoto
The problem with using an ionic dissipator on a grounded boat is that you then are trying to disipate the negative charge of the entire ocean through this little stainless steel brush. It just isn't going to be able to do it.
Actually, the idea is that you're reducing the charge local to the boat, just a slight amount...and thereby reducing the potential of a lightning strike in that specific location. You aren't trying to dissipate the entire negative charge...that would be almost impossible, given how large the forces involved are.
__________________
Sailingdog

To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.

Telstar 28
New England

You know what the first rule of sailing is? ...Love. You can learn all the math in the 'verse, but you take
a boat to the sea you don't love, she'll shake you off just as sure as the turning of the worlds. Love keeps
her going when she oughta fall down, tells you she's hurting 'fore she keens. Makes her a home.

—Cpt. Mal Reynolds, Serenity (edited)

If you're new to the Sailnet Forums... please read this
To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.
.

Still—DON'T READ THAT POST AGAIN.
Reply With Quote Share with Facebook
Reply


Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)
 
Thread Tools

 
Posting Rules
You may post new threads
You may post replies
You may post attachments
You may edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is On


Similar Threads
Thread Thread Starter Forum Replies Last Post
Lightning Anyone? holy7cow Living Aboard 32 05-04-2009 11:33 PM
LIGHTNING SHIMSHON General Discussion (sailing related) 37 07-24-2007 09:13 PM
Anyone using the strikeshield CCSB for lightning protection? e31 Gear & Maintenance 3 07-23-2004 02:03 AM
Pearson Mast Step aphil138 Gear & Maintenance 4 05-29-2003 11:44 AM
copper boxes and electronics kwiac Gear & Maintenance 8 05-02-2002 06:34 PM


All times are GMT -4. The time now is 05:05 PM.

Add to My Yahoo!         
Powered by vBulletin® Version 3.8.7
Copyright ©2000 - 2014, vBulletin Solutions, Inc.
SEO by vBSEO 3.6.1
(c) Marine.com LLC 2000-2012