I am very hazy about the science of all this, so don't quote me, but
metal aircraft rely on good bonding to ensure that lightning has
somewhere to go without affecting the contents (i.e. passengers, radios
etc). As Carl suggested, I assume that the presence of metal in a
composite aircraft can have disastrous effects because there is nowhere
for the energy to go once it has entered.
My "Handbook of Aviation Meteorology" suggests that lightning strikes
can occur anywhere if the conditions are right, even in clear air,
though much more likely in CBs. It also suggests that a good way of
attracting a strike is to trail a long aerial or cable out the back :-).
The only strike I have had, happened flying through an innocent looking
cu (it was no more than 2000' in extent). Our passage through it set it
off, and all the others nearby.
Existing thunderstorms are not too difficult to avoid but we have no
way of telling when the conditions might be right in other
circumstances.
So I have a fairly fatalistic approach to this, in that if my Europa is
struck by lightening it probably won't do me much good, but on the
other hand the chances of that happening are relatively slim,
particularly flying VFR most of the time. On the other hand I am more
concerned about the turbulence that CBs produce. Even a quite small CB
can produce enough turbulence to make flying a light aircraft very
difficult, not just in the cloud; windshear near the ground can
seriously damage your health.
Paul Atkinson
ps I heard a story once about a metal glider that broke an altitude
gain record in Argentina. The pilot thermalled into the base of a CB.
When he regained conciousness the tail of his aircraft was at an odd
angle but it was still flyable. The barograph, which had been running,
showed that he had broken a record by a considerable margin. I suspect
that he would have enjoyed the experience far less if he had had his
oxygen mask on.
> From: n3eu@comcast.net
> Subject: Re: Europa-List: Lightning Strikes to Composite Aircraft
>
>
>> Hi All,
>> According to the AAIB at the last PFA Rally at Kemble, aircraft do not
>> attract lightening, so it will only strike if the aircraft flies
>> through the
>> path of lightening when it is already travelling. This is my
>> understanding
>> of what was said. I therefore try to give CBs a wide birth.
>> Regards,
>> William
>
> Perhaps the AAIB guy didn't come across so clearly, or the "dog ate
> his homework."
> The below research document is long and technical, but the very first
> sentence
> will do: "Not until the 1980's was it convincingly demonstrated that
> the
> vast majority of lightning strikes to aircraft are initiated by the
> aircraft,
> as opposed to the aircraft's intercepting a discharge in progress."
>
> http://plaza.ufl.edu/rakov/ProgressinAerospaceSciencespaper.pdf
>
> Regards,
> Fred F.
>
>
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