Corona breakout voltages?

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

Original poster: "Terry Fritz" <twftesla-at-qwest-dot-net>

Hi All,

There is this well known formula for corona of 3MV per meter of radius.  If
I have a 1 meter radius sphere, I can but 3,000,000 volts on it before
corona breaks out.

So I used to work on 375kV power lines, they were about 1 inch in diameter
(0.0127m radius).  0.0127m radius suggest a corona voltage of 38,100 volts.
 So at 10X that, those lines should have been glowing and streamering like
crazy!!!  375kV was also an "RMS" voltage...

I am having trouble getting little spheres to corona at the voltage I think
they should (seems to take far far higher voltage) and I think what ever
held corona back on those high voltage power lines is also holding back
corona in my sphere experiments.  Is the surrounding air just charged up
and acts to reduce the e-field or something???

I am just wondeing if anyone has any insight into this or can tell me what
I am missing in all this?

Cheers,

	Terry