ER Tank Designed

ww2planes · #1 04-15-2006, 04:53 PM

Well I have cut the material and made a mock up of my ER Tank. I am only putting one in due to my flight mission profile. Based on the numbers the one tank should get me 9.3 gallons. It will work very similar to the SafeAir 1 system with a significant design change to get the additional quantity. I figure that I now have a 45 minute reserve and will be able to extend my range by a comfortable margin.

It is straight forward to install and is easier if you are able to do it while skinning the wing but I am sure that I could do it in a retrofit situation as well. I have an estimated weight of less than 15 pounds for the entire system. I will know more as the design gets closer to being completed.

I thought about making one for each wing but I don't think that either my wife nor I can sit that long. If I did however, I would be looking at nearly two extra hours of flight time and would have over a 1000 mile range. Sounds appealing but that may be too far in one shot for me.

Forgot to mention, Weight and balance issues should be nil with my design.

DeltaRomeo · #2 04-15-2006, 05:24 PM

Happy Easter, Bill !

Whenever you have pictures of the mockup I probably speak for several when I say I'd love to see them.

Best,
Doug

Bob Axsom · #3 04-15-2006, 07:11 PM

I have 17 extra gallons in two span extending tip tanks and I use them. You mention weight and balance is not an issue but if you put an extra 50+ pounds of fuel in one wing you are going to have to compensate for that and the tank weight somehow. I would go for the 1000 mile range two tank configuration and land with a little extra reserve. You know the old saying that you can only have too much fuel if you are on fire - I think it has merit. Theoretically, I should have 5.5 no reserve hours at a conservative planned 10 gal/hr burn rate on my O-360-A1A but I get VERY unsettled when I hit the 4 hour mark and I'm not within glide range of my destination.

Bob Axsom

ww2planes · #4 04-15-2006, 07:24 PM

I had thought about doing both tanks but I built the first wing without the ER Tank. I had figured that I can use my aileron trim to offset the heavy wing if it were an issue. I plan on building a trim tab into the aileron. I am putting the tank in the right wing and I am fairly sure that my chubby physique will offset the heavy wing. I theorized that a 9 GPH Burn would yield a duration of just over 6 hours if I had both tanks. That will never happen so I decided to just go with the one.

By the way, are there any builders out there that would be interested in these types of tanks?

jarhead · #5 04-15-2006, 09:45 PM

Quote:

Originally Posted by ww2planes

By the way, are there any builders out there that would be interested in these types of tanks?

I'm building eventually, so I'd like to see some more concrete info...

osxuser · #6 04-15-2006, 11:54 PM

Interested yes, but what are the advantages over just pushing the main tanks out one more rib, and making new skins? That's what a -4 guy I know did.

ww2planes · #7 04-16-2006, 12:08 AM

I did not want to modify the outer leading edge for several reasons. I did not want to re-make the rib or deal with the skin, a new bulkhead and figuring out how to attach it to the spar. Besides, I am entertaining the resale advantages of my design and if I modified my leading edge I just don't think that many folks would want to remove ther leading edge and make it all over again and deal with that many headaches. New install is not so much and issue but a retrofit in an existing wing would be terrible using the leading edge theory.

Thanks for the interest.

osxuser · #8 04-16-2006, 10:14 AM

Right, for retrofit my idea for the mod would SUCK... Do you have drawings of how it's gonna work?

Pirkka · #9 04-16-2006, 12:22 PM

There are just couple of modifications I've planned and ER tanks are one of them. Therefore all ideas are welcome and I'd like to see different ways to implement them before choosing my way to do it. Also interested details like how thick material you are using and such...

Anyone know details about SafeAir tanks? Thickness etc.

ww2planes · #10 04-16-2006, 04:49 PM

This is an overall of the system. I had to redesign the end tank as I did not have the quantity that I wanted yet. This is the new tank. I checked the clearances today and it has about a 1/2" inch at the closest points so I hope that will be enough.

http://img115.imageshack.us/img115/8000/p10002035zk.jpg

After doing the math I show that these will hold about 10.3 gallons. That is the perfect number for me. I figure that conservatively, there will be about 1/2 gallon of unusable product in the tank. At 9.5 usable this is the perfect size.

Now to ordering the hardware and the welding of the pieces. I hope this thing works.