Re: Static Electricity

james nolan (nolan_laboratories@email.msn.com)
Tue, 3 Aug 1999 15:42:44 -0600

- - - - - - - - - - - - - - - - - - - - - - - - - - -
West Wight Potter Website at URL
http://www.lesbois.com/wwpotter/
- - - - - - - - - - - - - - - - - - - - - - - - - - -
John:
I think what you were experiencing was total rapture with your Potter.
Neptune's cupid had struck you. Actually what you were experiencing is
Faraday induction. High up in the sky the clouds and surrounding atmosphere
were charged by thermal cell activity and unipolar induction. This large
"sheet charge" induces an equal and opposite charge in the ground below
(sometimes in the ionosphere above) . The large equal and opposite charge is
distributed over the ground and water below. Singular points such as masts
and lightning rods develop high voltages because the charge is concentrated
in a small area. It takes about 3-5 thousand volts to create a spark, and
the rule of thumb is about 25 kV per inch of arc. These sparks don't mean a
strike is just about to occur, they just mean the air is charged. It is a
good sign that lightning storm is coming. When I experience this phenomena I
usually take shelter until it passes.
A good safety tip is to carry an atmospheric galvanometer with you. It is a
simple device in a glass jar with two foil leaves inside. The separation
between the leaves (angular separation) gives the charge density of the
small sphere on top. This device is very sensitive and can warn about storms
very early. They are used at Colorado ski areas to warn skiers of impending
lightning. Do not store the galvanometer near a keel unless it is
degaussed. This could spell trouble.

Jim Nolan P-19 #426 P-15 #1055 GLYC Bouy #6 Loon 138T

-----Original Message-----
From: John Haley <haley@geneseo.edu>
To: wwpotter@tscnet.com <wwpotter@tscnet.com>; precision@puremagic.com
<precision@puremagic.com>
Date: Tuesday, August 03, 1999 7:40 AM
Subject: Static Electricity

>- - - - - - - - - - - - - - - - - - - - - - - - - - -
> West Wight Potter Website at URL
> http://www.lesbois.com/wwpotter/
>- - - - - - - - - - - - - - - - - - - - - - - - - - -
>Greetings,
>
>Last weekend I launched my P18 just before a summer thunderstorm was to
>arrive. Lake Ontario was emptying of small craft. I intended to quickly
>motor over to a transient slip assigned to me, a very short distance within
>a protected harbor.
>
>When I got in the cockpit I received a mild static electricity shock from
>my outboard. I thought nothing of it, I get similar shocks from cars and
>such. Touching it again I received another, and another. I was literally
>able to tap the outboard like morse code and receive a shock every time. I
>checked to make sure the battery was unattached (it was). I held the motor
>to ground it out and quicly attached the gas line and scooted over to the
>slip. Grounded the motor again while removing gas line. Removed gas can
>from boat and went for lunch to watch the storm blow through.
>
>Clear skies afterwards and no shocks from the motor.
>
>Was this my mast soaking up electricity from the air or what? Hind sight
>leads me to believe that attaching the gas line was a mistake. Has anyone
>had experience with this? Are there precautions? Your thoughts and
>experience would be appreciated.
>
>John Haley
>P18 156
>Rochester NY
>
>
>
>........................
>John Haley
>Systems Manager
>Division of Administration & Finance
>SUNY Geneseo
>(716)245-5548
>haley@geneseo.edu
>