Tesla coil limits

["Tesla list" <tesla-at-pupman-dot-com>]

Original poster: "by way of Terry Fritz <twftesla-at-qwest-dot-net>" <Michael.Day-at-USPTO.GOV>

Greetings all,

The Lightning-On-Demand web page at www.lod-dot-org states the following:

"The physics of air under electrical breakdown limits the maximum practical
size of a Tesla Coil to about 12 stories in height.  Greg Leyh started
Lightning On Demand (LOD) in 1996 as a focus for designing and constructing
a Tesla coil system that would operate at this limit.  In addition to posing
an interesting engineering challenge, this facility will provide a unique
scientific research platform for studying natural lightning phenomena -- and
operate as an world-class educational attraction for the general public."

Does anyone know why the physics of air under electrical breakdown limits
the maximum practical size of a Tesla Coil to about 12 stories in height?

-mike day