Main tank Useful Fuel

[Robert Lees]

Re: Main tank Useful Fuel

Well now you've found your voice, keep posting!

Rob

[Dano"T"]

Re: Main tank Useful Fuel

My C90 powered BC12D on floats will un-port on takeoff with 3 gals in the tank..once I break the water, the combination of the sudden acceleration from breaking the water combined with climb angle and added fuel flow of the C90 and it will un-port and go quiet every time with under 3 gals in main tank.....if I level off it starts again. Much more prominent on floats due to sudden acceleration caused by liftoff. The fuel sloshed back and sputter....sputter.

[PA1195]

Re: Main tank Useful Fuel

My C90 powered BC12D on floats will un-port on takeoff with 3 gals in the tank..once I break the water, the combination of the sudden acceleration from breaking the water combined with climb angle and added fuel flow of the C90 and it will un-port and go quiet every time with under 3 gals in main tank.....if I level off it starts again. Much more prominent on floats due to sudden acceleration caused by liftoff. The fuel sloshed back and sputter....sputter.

Interesting observation. There are demands for flow volume and pressure that have to exceed any restrictions from the fuel line's diameter, and filter screens in the gascolator and carburetor (assuming they're clean). Without an equivalent of a baffled main tank or separate header tank perpendicular to the engine I can see where the fuel could slosh rearward, or at least be temporarily un-ported in rough water on floats.

Probably best to not T/O with less than 3 gallons and then climb at a steep angle with the large engines. Probably no need to have that little fuel to begin with if it's a known issue.

The CAR 3 part2.PDF I noted above discusses the flow requirements that sets limits for unusable fuel for the F19 and 200 ci engines.

Gary