>The recent damage to a Europa due to static discharge during fueling inspired
>addition of tank grounding to my plane. The information at the sites
>suggested by Fred Fillinger was most helpful in deciding how to proceed:
>The ohmmeter shows that all the targeted fittings are connected and in
>addition wherever the original cotton covered line has not been replaced
>there is a resistive connection.
>One additional wire is planned between the engine ground and the
>undercarriage to provide grounding via the conductive mainwheel tire - this
>will be added when the lower cowl is next removed.
I'm now firmly of the opinion that solid Aluminum fuel lines from the tank
outlet to the firewall is the best answer. I ran the line from the pump to
the firewall along the top of the tunnel to within 5 inches of the firewall
then up through the top of the tunnel , placed to miss any instruments etc.
to a couple of inches above the tunnel. Then I used a 45 degree bulkhead
type fitting (AN837-6D) to take it through the firewall, (the fixed part
not the bit of stainless steel.)
The soft aluminum tube was held in place with 2 plies of BID over most of
its length.
I am still head scratching about the mechanism of this static generation
problem, bear in mind I have a part share in a Long EZ too. I wonder if the
contra flow of fuel versus air has any bearing on it? Any ideas?
Graham
>Of course, there is always a question remaining: should a section of safety
>wire be added such that it extends from the filler fitting down inside the
>filler pipe or is this superfluous due to a low breakdown voltage of the
>interior insulating layer in the filler hose?
>
>John, A044
>
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