Fred,
I agree with you that bonding other metal parts in the fuel system to the filler
cap is probably less safe rather than more so. However if fuel drains are
fitted,
I think it's a good idea to ground them independently. Although it's a fairly
remote possibility the last thing you need is a spark when you are lying
on the ground draining fuel!
Best regards,
Nick
Original Message
---------------
From: Fred Fillinger <fillinger@ameritech.net>
Subject: Re: Europa-List: Static Charges and how to avoid them
DuaneFamly@aol.com wrote:
> So am I to conclude that there should be two separate electrical bonds
> in the plane? One for all the regular things that need electrons to
> operate (lights, engine, instruments, etc.) and a separate one that
> bonds the various nonoperating parts of the fueling systems to a
> single point that one can attach a ramp ground wire to and the
> container that the fuel is presently in when refueling.
There is no need for the A/C's electrical system ground be involved, but
a practical consideration is that airport fueling personnel will attach
the bonding wire to the exhaust pipe. One need minimally only bond the
metal filler opening, so I suppose one could placard the filler to that
effect and provide a means of attaching the clip.
If by "bonding the various nonoperating parts of the fueling system"
means other than the filler cap, then I believe that's more hazardous.
What will happen is that any static accumulating in the vicinity of
those metal parts will be sent to the filler cap, unnecessarily raising
its voltage potential. If the filler cap is also earthed in some way,
then there's no hazard. Even one's body can drain off the charge if the
conditions are right. However, it's best to leave any static deep
inside the system, and this is the reason that filling an ungrounded
metal can is more hazardous than a plastic container, where static
charges tend to remain where they accumulate.
Regards,
Fred F.
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