The inevitable fuel spill disaster

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Re: The inevitable fuel spill disaster

Postby sonex892. » Thu Aug 29, 2024 6:43 pm

Skippydiesel wrote:I have asked this before - yet to get an answer.

Is there some reason why the fuel point can not be moved in front of the firewall ie forward into the the rear of engine bay. A suitably designed flap (size & hinge point), could open to prevent splash onto polycarbonate and any overfill, would drain out of the bottom of the engine bay OR be caught by a well/bund arrangement, that could drain through a pipe onto the ground.

I sure hope the new high wing comes up with a better, fueling, arrangement.

It appears the high wing is using the same through the lexan fill point. I get nervous enough filling an A model tank adjacent to the lexan.

Skip this is off topic. Do you have a schematic of your fuel system including venting you would be willing to share? I'm at the decision point on the Sonerai I'm building. I has 2 x 35 litre wing tanks and a 24 litre header.
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Re: The inevitable fuel spill disaster

Postby Skippydiesel » Thu Aug 29, 2024 8:04 pm

sonex892. wrote:
Skippydiesel wrote:I have asked this before - yet to get an answer.

It appears the high wing is using the same through the lexan fill point. I get nervous enough filling an A model tank adjacent to the lexan.

Skip this is off topic. Do you have a schematic of your fuel system including venting you would be willing to share? I'm at the decision point on the Sonerai I'm building. I has 2 x 35 litre wing tanks and a 24 litre header.


Sorry no schematic & even if I had one, never been able to add a photo on this Forum

The original plans builder (I am the finisher) had some interesting ideas:

My Legacy has 30L wing tanks and a 40L in fuselage header (filled from wing tanks).

The current breathers are:

    Wing tanks breath to the opposite wing tip, to prevent spillage when banking or parked on a slope

    The in fuselage tank breather, has not been so well thought out. The breather is from the REAR of the tank , routed forward to the firewall, down to floor, back to wing spare/box where it exits down. This is a tailwheel aircraft - means that the tank can never be filled to its 40L capacity on the ground. Safe non venting filling is 35L. Occasionally I land with up to 38L remaining, 2-3L will exit via the vent.

    When I get round to fixing this, the vent will be from the front (high point) of the tank - up as high as I can get it under the glare shield - down the firewall - out the floor

I have always advocated for a simple one line/pipe breather system (all tanks into one line), through an expansion tank, that rises, as near to the highest point (vertical stabilizer) as practical of the aircraft, before exiting the bottom/tail. Benefits are almost no chance of liquid fuel venting, no problems with slope, unlikly to vent in a climb, any fuel vented collected by expansion tank with potential return as fuel consumed, no smell of fuel in cockpit, does not contact the aircraft skin (stains)
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Re: The inevitable fuel spill disaster

Postby WaiexB22 » Fri Sep 06, 2024 12:54 am

I too will fill from home 95% of the time. I am considering adding a fill line to the side of the plane. I would then pump into this line rather than using the factory fill neck in the middle of my windscreen. I am looking for a quick connect I could use. Anyone have any recommendations?

Also, FWIW, the high wing is supposed to have an option for factory aux tanks in the wing. There would need to be fill locations for those tanks. I would just fill the wing tanks (assuming the fill is away from the windscreen), then feed those via gravity to the main tank.
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Re: The inevitable fuel spill disaster

Postby Skippydiesel » Fri Sep 06, 2024 3:43 am

[quote="WaiexB22"]I too will fill from home 95% of the time. I am considering adding a fill line to the side of the plane. I would then pump into this line rather than using the factory fill neck in the middle of my windscreen. I am looking for a quick connect I could use. Anyone have any recommendations?

Also, FWIW, the high wing is supposed to have an option for factory aux tanks in the wing. There would need to be fill locations for those tanks. I would just fill the wing tanks (assuming the fill is away from the windscreen), then feed those via gravity to the main tank.[/quote]


This is similar to my Sonex - however in mine there is no way to fill the fuselage tank, other than from the wing tanks. This makes the 40 L fuselage tank a large header. Easy enough to do the same for the High Wing.
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