I just fixed a guys handheld with about the same symptoms. Most of the
problem was some corrosion on the bnc for the antenna so he wasn't getting 
a good ground. He's flying a Rebel so everything is connected, I take it
your friend is in a Q Dlfy etc and using the copper foil antenna? The 
connection on the sheilding become a bit more critical. He does have the
ferrite beads near the antenna?

Dave

> A pilot friend has asked for help with what he thinks might be
> a static problem
> 
> He flies a small single-engined plane, the majority of which is
> made of fibreglass. His comms (124.2MHz, 5W) work perfectly
> on the ground, but after a while flying he notices noise. This
> happens only after the first transmit or receive. He says the noise
> is more noticeable after a transmit. One cure he's found is to switch
> to another channel and then back, and the noise goes away. But
> he doesn't need to transmit, simply changing channel and then
> back again is enough. The aerial is a strip of copper foil, approx
> 1m long, embedded in the rudder. He wasn't able to tell me if
> the noise is more likely in dry or humid weather, or whether it
> would go away if he flew through cloud. He says he doesn't get
> a shock when he leaves the plane either
> 
> Any ideas ?
> 
> TIA
> 
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