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Re: REFLECTOR: Fuel Tanks

>If you don't fuel your airplane yourself.  Have the lineboy
>fetch his fuel nozzle.  Put one hand on the fuel cap and
>shake the lineboy's hand with the other.

You got it!

>Someone did the math once that calculated the capacitance
>of a fiberglass airplane.

For that purpose it's enough to calculate the capacitance of the fuel cap.
(as long as you didn't connect it to anything else). Turns out to be about
0.1pF. That's tiny. It means it can hold about a million electrons per
volt. That may seem like a lot but it isn't. Probably not enough electrons
to create a channel of fully ionized air (aka "spark").

Now, if you add to the capacitance by connecting all sorts of shiny pieces
to it like tie down rings and such, the picture may change but it probably
doesn't make it outright dangerous.

I've heard of only one spark induced fire on a fiberglass plane. Sorry, I
didn't keep the reference. All I remember is that this happened to a guy
who was very worried about that possibility and he had actually connected
his fuel caps to just about everything metallic on his bird. Simply turned
it into a big capacitor.

The most dangerous situation I have encountered so far while fueling was in
a totally different chapter: Nice lady pulls up the fuel truck, I say "20
each wing please" open the caps for her and go fumble something inside the
cabin. Before long she changed to the other wing and I say to mayself
"gosh, that was fast" and watch the meter this time. Sure enough: she had
put TWO gallons in each wing! Just imagine if I had not noticed: go pay for
40 gallons, up the fuel computer by 40 and head out over the Gulf towards
the Big Easy!? Makes me shiver every time I think about it. (No, I havn't
seen her since)


Simon Aegerter, Winterthur, Switzerland