[BC] Transmitter Safety

[Ron Nott]

Kinetic energy of an airplane travelling through the air can charge 
the surface of the metal to 300 kV or more.  This results in corona 
from the trailing edges of wings, rudder and elevators to discharge 
corona which causes radio noise.  To decrease this effect, most 
aircraft now have "brushes" of conductive fibers located in small 
metal cylinders on the trailing edges of all the surfaces.  The 
charge dissipates from the sharp points of the fibers at relatively 
low voltage.  These brushes are frequently inspected and replaced as 
they are consumed by the corona discharge.  The principle of 
operation is the same as in a charge dissipator that discharges the 
electric field at the top of a tower.

Next time you are on or near a plane, look closely at the trailing 
edges of the wings for little black cylinders attached there.

Ron Nott, DVP

----- Original Message ----- From: "Ronald J. Dot'o Sr." <ron.doto at comcast.net>


>I've read that during the WW II era that "Precipitation Static" from 
>snow was a big problem for aircraft MW and HF equipment in aircraft 
>making reception all but impossible at times in northern latitudes 
>from the dry snow brushing against the longwire antennas in the 
>slipstream.  Things got a lot better when VHF came into use for aircraft.