Fred, The snag about the flow rate is that in a large caliber pipe the fuel
will accelerate at something like1g and in a 3ft vertical drop from standing
start this produces 13.6 ft per sec. I guess the fuel pipe is not 3 ft long
but the fuel doesn't have a standing start either. Regards, David Joyce
----- Original Message -----
From: Fred Fillinger <fillinger@ameritech.net>
Subject: Re: Europa-List: Static Charges and how to avoid them
<fillinger@ameritech.net>
>
> > Fred
> > My plan is to dissipate any static charge generated. We know it
> > does arise, G-BWDP caught fire. I am reliant on the memories of
> > two guys, one of whom got burnt on the arm, so their memory of
> > the sequence of events might have been diluted by the trauma at
> > the time.
> > ...
>
> Graham, were both the above incidents while hoisting up fuel containers
> to pour in fuel? In that case, refiners say a metal can is more
> hazardous than plastic (why they're hard to find in stores here). If
> you know of two such incidents, then maybe there is indeed an especial
> hazard with fiberglass airplanes. The following is quoted from a doc
> (by NZ's CAAA) reprinted by FAA, discussing fueling from portable
> containers:
>
> "No amount of bonding and grounding will prevent discharges from
> occurring inside a fuel tank [in context, this includes metal tanks
> too]. Bonding, however, will ensure that the fueling equipment and the
> receiving tank are at the same potential...."
>
> "Place the container on ground. Keep the nozzle in contact with the
> container inlet during fuel transfer."
>
> "A composite aircraft is more likely to develop and sustain a static
> charge because of the low conductivity of the fiberglass structure."
>
> IOW, a safe way is a metal can preferably on the ground, metal nozzle
> and conductive hose, bonding wire from can to filler opening, stand
> clear of A/C. Pump it in with electric or hand pump, with flow rate in
> the hose below the magic # of 12 ft/sec (30 gal/min in a 1" ID hose),
> which should be no problem in an affordable pump!
>
> Best,
> Fred F.
>
>
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