In my opinion fuels pumps belong in the fuel tank,
either the mains or collecting header tank.

Doug in Japan




Which means in my plane that a 'high-pressure' line will be running through
the cabin (RV-6) instead of a suction line.
Not sure I really like that...

BrianG
Iowa


Excellent point. Thanks for bringing that up. I almost
crossed over to the other side.
C. Smith

Brian

Brian,

Yep good point and you are obviously considering fire.  Well
none of us like the idea of being surrounded by huge fuel tanks
and high pressure fuel lines but the fact is we are.  Just
because they might be on the other side of that thin firewall,
in a crash or even a slight crunch, the airplanes structural
components deform or rupture.  The design concern is to choose
the fuel line material and routing that  offers the best chance
of maintaining its design integrity in a crunch.

When we run the 'what if'  scenarios we can then design systems
to cope with the multitude of risks. We can't eliminate them.
Well<85 I take that back, perhaps we could but then wouldn't be
flying:)

The point we should be considering is how to disable and isolate
the source of fuel right at the tanks.  This would entail
emergency shut off valves that could be activated by pulling one
cable.   That big red knob could be set up to de-energize  the
fuel pumps as well, and perhaps at the same time another one
valve could depressurize the line.

Fire extinguishers?  Yes of course.  A nozzle going to the
engine compartment near the hot zone and another in the cabin.
Fuel lines should be chosen that are high quality, rupture
resistant, and placed in a manner that minimizes risk to the
occupants.  This could mean enclosed within the structure

Since you are considering an engine that requires high pressure
fuel to the injectors, to maintain the injector manifold
pressure unused fuel will have to be returned somewhere.  Where?
Or maybe I assume too much.   Are you planning on running a
carburetor?

Doug in Japan