"Jack Painter" wrote in message
news:emUDd.11563$B95.6120@lakeread02...

"Ed Price" wrote

SNIP

Regarding the RF excitation, I assumed that a single-point source would
be
dumb, because the best ionization path would be right back to YOU. But an
array of exciters, electronically steered to create a sufficient power
density at a focal point, is a lot smarter.

Again, I don't know if the technique would work, but an electronically
steered (more like focusing) array would be one way to do it.

One poster said that the ionized channel might blow away in the wind.
Maybe
a quick system could "paint" an ionization channel fast enough. Maybe a
system could detect and take advantage of leaders, to create a shorter
path.

Ed
wb6wsn

Hi Ed, using high powered lasers to "paint" a thunderstorm cloud has been
done, and whether reliably or not, was able to trigger lightning. It
hasn't
translated into practical protection schemes yet, but that could simply be
economics. As a means of triggering lightning to a safe point away from
vulnerable assets, it still leaves the possibility that some storms are so
powerful that nothing short of an extensive, multi-point array of lasers
could ever offer protection at an individual point. It is generally so
much
less expensive to employ catenary wires overhead, build faraday-cages
around, and position air terminals in appropriate areas than the costs of
such a laser system. There would also be a new class of airspace required
for operation of such lasers. Something like a "no-fly zone" in fact!
;-)

73,
Jack Painter
Virginia Beach, Virginia




More like a "dead-fly" zone. Yeah, aircraft (and satellite / astronaut)
protection are not trivial concerns when you start squirting power into the
air.

BTW, I seem to recall the use of small (sounding?) rockets used around the
perimeter of the Kennedy launch complex. I don't recall if these rockets
trailed a thin wire, or if their exhaust plume was sufficient to trigger a
lightning discharge. Anyway, I thought I recall these small expendable
rockets being used as a lightning diversion technique to protect the exposed
launch vehicle. (Yes, I know they also use catenary wires from the tower to
the ground, but the rocket technique was supposedly to condition the area
around the vehicle just as launch occurred, and the tower was moved away
from the vehicle.)

Ed
wb6wsn