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Re: Ewart Accident


> > It's interesting to note several references to "No Radio."
> >
> > Wonder if Mark had ever checked his antennas after building them?
> > My experience has uncovered lots of defective antennas in glass planes.
> He had the same wings as you.  He brought the plane here were we replaced
> the wells and rudders with glass ones.  Then we tested his old antennas
> with our new $1,000 meter.  They were as good as the "sportcrafts" we had
> installed in another set of wings except above 130 mhz effeciency dropped
> off like all standard length RST com dipoles.
> Alan

The antennas in my wings were defective out of the box. One issue was the solid
conductor co-ax, which in aircraft applications is subject to fatigue breakage
and can lead to intermittent antenna failure. That's why my ears perked up when
I saw the "No Radio" reference in the Ewert case. Another issue was carbon
fiber, which we now understand should not be used near antennas.

My antenna experiences started me on a crusade to alert builders to the
importance of testing their antennas before glassing them in. I'd even suggest
checking them again after major work in the vicinity of the antennas, such as
glassing, filling, or painting.

Last week I rechecked my antennas after painting the wings. In my case the paint
made no significant difference in antenna performance. The Sportcraft Comm
antennas still check very good to excellent across the whole band, while my
unmodified Navs remain poor.

Dave Black