The Cub Den

If you have come to this page to learn how to hide your Army Tank you are at the wrong place.

We are going to talk about hiding that fuel tank in a plane.

Cubs along with many other scale planes are hard to hide the fuel tank due to the fact of not much room to hide it. You do all that work on a scaled out cockpit and then have an ugly tank in the middle of it. Lets say you have a 1/4 Cub with a 26CC engine up front. I have seen recommendations is from 12 to 16 oz tank. This is a cub and probably wont be flying full throttle and doing 3D so lets go on the smaller size. A Dubro 12oz tank is 5 3/8 inches long. Cant hide that under the dash on a 1/4 scale. Most pilots are not up to make a tank line the old Control line guys did back in the days.

So a new option that many don’t think of is duel tanks. The glow Helicopter guys have done this for years. They refer to the second tank as a header tank. Now I have you thinking and wondering how will I set it up and plumb it……. Keep on reading. I have ran this setup in my Cream 1/4 cub starting back in 99 and in my L4 back in 09. Both Cub setups are the same except for the tank size. I will be talking about my L4 on this page.

For several years I attend a fly-in at Dayton Ohio at Wright Patterson Airforce Museum. I loved flying in the noon show. The MC would talk about the role of observations planes in the war as I would take off. As soon as I was up the war bird gaggle would start and go on down low as I did my slow observations passes up high. They would all land after about 10 min and then I would come down. Had many of the warbird guys ask how much fuel I had onboard as I would out last them in the air. When I told them only 10oz they could not believe me. I have been known to get 20 minuets of flying time on 10 oz of gas. I run a 4oz and 6oz in parallel. You do not have to stay with one brand of tank. The 4oz is a Sullivan tank and the 6oz is a Dubro tank.

First figure out what size tanks you need to give you the amount of fuel you need but can be hidden under the dash. For me it was a 4 and 6oz tanks. Next figure the layout you need. I went with the 4 oz on its side next to the 6oz tank.

Now that we have all that figured out lets get to the plumbing side. Each tank on the inside should be plumbed as a standard 2 line tank. One fill and one vent line. I always use a sharpy and write a V for Vent and F for Fill on the tank. Now we will be running in parallel. I always start with the small tank first. So connect a line from the fill line of tank A to you carb. Now from the vent of tank A run it to the fill line of tank B. Run the vent of tank B to outside of the plane.

As you fill the gas will fill tank A and then run thru the vent line into tank B when tank B is filled it will vent out your plane just like a normal setup. Now as you fly, you are pulling fuel from tank A. But because tank A vent is connected to tank B fill it will pull fuel and empty tank B first. As with all my fuel setups I recommend presser testing the setup under water for any leaks. My tanks I will wrap a few swipes of electrical tape around them and then Velcro into the location. Now with this setup you can finish scaling out your cockpit with a scale tank cover.

I know we talked about Gas above but this same setup will work with Glow. Just take the vent from tank B and attach it to your muffler pressure tap. Feel free to ask question.

Thecubden.org