B's new FX-3

[turbopilot]

I posted the scenario on the CubCrafters forum so we can open this discussion up to a wider audience.

FX3 Wing Fuel Tank Recommendation?

According to the CubCrafters configuration web page at http://cubcrafters.com/carboncub/fx3/configure it outlines 2 x 22gal fuel tanks for a total of 44gal. I've heard through others that this is actually four tanks, 2 x 12 gal inboard tanks with a 10gal outboard of each with an interconnect...

forum.cubcrafters.com

Andy seems pretty sharp. But we end up in the same place. There is a big question about the availability of the last 5 gallons in a 44 gallon system. So for planning purposes it is not useable. I sounds like if you ever get into a pinch and need some extra fuel there will be ways to get some of it out. The 24 gallon system has 1 gallon unusable and the belly tank has a 6 once unusable. They way you use a belly tank by cross feeding means you can use it all.

 

[Neal]

If I'm in a pinch needing that last 5 gals then it's the same as flying into known icing - stupid, etc.

I am not on board with deleting fuel tanks, that is my personal opinion and decision. I am not in the frame of mind of creating the lightest weight STOL aircraft here. I'm looking for a Carbon Cub (modern, not light) to enjoy local flying, off airport flying, stick flying, techie (Garmin G3X) flying and getting above the trees to take in the views early or late in the day and finally to meet others to share and enjoy the experience. If I wanted light I would go the SS route, polytone, no BRS, and whatever else that can shave weight. That is not my objective as well as not flying into or out of the shortest fields like I cringe watching Backcountry182 do. Just like @Tsquared with the 80/26 you have to design your plane for your desired flying and use and be happy with your decisions before and after.

 

[turbopilot]

I am not on board with deleting fuel tanks, that is my personal opinion and decision.

Well, at least you have most of the information. Those guys on the other thread are smart, experienced CC drivers. The information about the the 44 gallon fuel tank modification was mostly new to them. Give them some time to think about it. They are stuck at this point as they all ready bought the airplane in that configuration.

What is not known yet (show me the data) is this pesky rumor, from otherwise credible sources, that the belly tank may actually increase aerodynamic efficiency of the Carbon Cub. I have heard cruise speed improvements of 3 mph to 5 mph. I am very skeptical of these claims and have not seen anyone fully document this claim. It would be very easy to verify since the belly tank goes off and on so easily. If the belly tank really has this impact the deal is done. There would be no reason to have that funky 4 tank 44 gallon fuel system. I will run these tests when I get the new airplane.

 

[Neal]

If you're going to delete the extended range tanks in the FX3 for which the flight controls were designed for and add a belly tank and use polytone, then what is pushing you to FX3 @Schwbo? It sounds like you may want to order what @turbopilot is getting instead if it's not too late?