> Fred, The snag about the flow rate is that in a large caliber pipe
> the fuel will accelerate at something like 1g 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
That's a good point, but the initial drop is about a foot or less on the
older fill pipe, and in the tri-gear, the fuel will not see the vertical
part of the it. Unless you just pour the stuff down the hole from
a can, more unsafe yet. In any case where any nozzle is inserted down
the pipe, the velocity is limited by the nozzle itself plus other
factors, before free falling a few inches to hit a major slowdown in the
more lateral run of the pipe.
I understand the literature to suggest that static downstream of the
filler opening is substantially irrelevant. If the nozzle is in contact
with the opening, there simply is no gap for a spark to occur.
Regards,
Fred F.
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