[TowerTalk] spider balls

[k1ttt at arrl.net]

sorry i don't have time right now to get lots of details, but here are
some references that anyone working in the lightning protection industry
should be familiar with.

CIGRE "Guide to procedures for estimating the lightning performance of
transmission lines" oct 1991

Para 4.3:  Ra=14H^.6  (as the tower gets higher the average attractive
radius of strokes to the tower increases)

IEEE P1243 "Guide for improvind the lightning performance of transmission
lines"

Para 4.3: Ns=Ng(28h^.6+b)/10 "More flashes are collected by the taller
structure"

the reference this comes from is:
A.J.Eriksson 'the incidence of lightning strikes to power lines' IEEE
Transactions on Power Delivery Vol 2 July 1987, pp 859-870

As far as the claims on porcupines or spider balls...

Abdul M. Mousa, “The Applicability of Lightning Elimination Devices to
Substations and Power Lines,” IEEE Transactions on Power Delivery, Vol.
13, No. 4, Oct. 1998m pp. 1120-1127.

Paper was peer-reviewed by six reviewers under threat of lawsuits. Paper
states that these devices do not work as the manufacturers claim.

1997 Report on Dissipation Arrays, funded by FAA, Naval Research Labs,
NASA, and USAF

The report, 274 pp., compiled by 17 scientists and engineers from around
the world, provides no definitive physical or theoretical evidence that
lightning dissipation arrays prevent lightning. The USAF presented photos
showing the arrays being hit by lightning.