Hi from South Africa.
Restrictions on our "experimental" aircraft are less severe here,
consequently many South African homebuilders have been running their
engines (certified and other) on Mogas for many years. We thus have some
experience with filling from containers or fuel pumps, especially into
ungrounded fuel tanks. The big bang theory is alive, our lost loss was
beautiful Skybolt that burnt to the ground in less than three minutes.
Two problems arise.
1. The sloshing has created some potential in the tank, and upon
bringing the fuel filler nozzle (earthed nicely) to the tank - poooooof.
2. The process of fuel transfer (from a pump or siphon from a container)
generates static as the tank fills (swirling sloshing and fuel movement
through the filler hose) - pooooof.
Most of us have a "little bare wire" with a weight on it that we drop
into the tank and connect with a crocodile clip to the fuel filler
nozzle (done physically away from the opening of the tank) avoiding poof
no 1 by moving the spark (if any) away from the fuel filler with its
lovely source of vapours. The filler nozzle is then brought to the tank
and left connected during the filling process avoiding poof no 2.
The downside - you need an accessory that has to be left in your plane.
Hope this helps or perhaps you can develop a variation on the theme!!
Regards
Mark Beekhuizen
(no decision to purchase the kit yet, or should I just buy that Glastar
instead?)
>-----Original Message-----
>From: JohnJMoran@aol.com [SMTP:JohnJMoran@aol.com]
>Sent: Wednesday, May 07, 1997 4:00 PM
>To: europa@avnet.co.uk
>Subject: Gas Tank Grounding ?
>
>After reading that pessimistic little pamphlet on Mogas supplied with
>the
>Owner's Manual, I have some questions on how to handle grounding of the
>Europa's fuel system. According to the pamphlet, fuel sloshing in
>plastic
>containers can build up a charge which results in a spark when the
>container
>is brought near earth potential. Fuel sloshing in a plastic container
>sounds
>much like the Europa fuel tank and the nozzle of a fuel pump is
>deliberately
>connected to earth potential, so is there a potential (pun intended)
>problem
>here?
>
>There are no instructions to connect the fuel filler to common. The
>internal
>filler hose does not measure as conductive so the filler seems
>isolated. Does
>this avoid the problem?
>
>The fuel hose material marked with the red stripe has embedded copper
>wires
>and the outside material is conductive according to my ohmmeter.
>However, the
>inside material in this hose does not seem to be conductive so there is
>no
>conductive path for fittings inserted into the hose.
>
>Overall, the fuel system seems to be electrically disconnected from the
>engine. Most fueling operations include connecting a ground wire to the
>exhaust pipe which in this case seems to be irrelevant.
>
>Is static electricity not a problem due to the nature of composite
>airplanes
>or should I be connecting ground wires to each of the tank fittings?
>
>
>Regards, John Moran A044 (Weird Questions R Us)
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