Auxiliary fuel tanks in the Patrol

[BravoGolf]

I have been using the search feature but have not found any information about auxiliary wing tanks in the Patrol. Is that because no one has done it or that I am just not very good at searching the forums?

[Mark Goldberg]

No one has done that YET to my knowledge. I do know of 3 Patrols that intend to use the aux tanks. It adds about 30 lbs of weight. Mark

[JimParker256]

Scott,

I'm no expert on this topic, but lots of the folks over on the BackCountryPilots.com and SuperCub.org forums go into the boonies where there is no fuel, and they want enough to get in, fly around, and get back out. For some, that means permanently installing larger fuel tanks. But at least some of them don't want the penalty of always carrying the extra weight of the aux fuel tanks. So they carry the aviation equivalent of "jerry cans" of avgas in the back seat or baggage areas. Lots of different solutions preferred by different people. Personally, just the thought of "tied down" fuel containers in and airplane gives me the willies... I can picture too many ways for that to go bad...

If I felt the need for aux fuel, but only on rare occasions, I think I'd be more inclined to rig up a 30-gallon removable tank that could be temporarily (but very securely) installed either under or right behind the rear seat in the baggage compartment. It could be plumbed into a fitting in one one of the tanks with a quick-disconnect, and use a small boost pump to pump the fuel into the main tank.

Or, don't even connect it to the fuel system, and just use a small 12V powered transfer pump and enough 3/8-inch flexible tubing to reach from the ferry tank to the fuel filler up on the wing. You'd have to land to refuel, but odds are you're landing somewhere anyway... If the need was very occasional, I'd probably lean this way over a quick-connect fitting.

(And don't forget to figure out a way to vent the tank to the outside of the airplane. Nothing like the smell of avgas in the cockpit over a long day to make you wish you'd stayed home.)

PS - as for me, I'm sticking to Bob's plan and the fuel capacity it provides. My personal range between pit stops rarely exceeds 3.5 hours, anyway... If I need to go 8+ hours into the back-country, I'll probably be flying with some Cubs, so the "long-range patrol speed" of 100 mph burning about 5.5 gph should allow me to keep us with them pretty nicely.

[BravoGolf]

I have looked at an tank located inside the aircraft and that is relatively easy to design and secure compared to extra tanks in the wings.

I am getting close to the point of no return on my wings and thought I would investigate the extra wing tanks. With all the creative folks building Bearhawks and Patrols I figured someone would have figured out how to do it by now. I believe the Bearhawk tips has some information about crossing the vents left wing to right and right to left, but that is on a Bearhawk. Although that could be adapted to the Patrol. The plumbing is also something to design, but again copying the design from the Bearhawk would work. I am more concerned with the wing structure and what modifications folks would have made to support the tank.

I am a point where I still have access to the wing internals. Once all the skins go on I won't be interested in attempting extra tanks.

[Bcone1381]

You should do it. If you asked yourself "How are aux tanks typically installed in the Model B?" then followed up with "What prevents that installation technique from being used in the Patrol?" I doubt you could find an answer to your second question. So go for it, then document your installation here for the benefit of the community.

[BravoGolf]

That was kind of my plan, copy the Bearhawk. I really was hoping someone had been down that road and I could learn about any potential problems.

[Bdflies]

I'm gonna be the spoiler here. My Patrol (std tanks) carries 55 gallons of gas, so I’ll base my argument on 50. I’m flying an O-360, nothing special. LOP, but conservatively, I’m seeing 6.6 gph at 123 mph TAS. That gives me a "no fuel" range of 960 miles. Another way of putting it, is 7.57 hrs till you’re flying a glider, or 3.7 hrs "one way". 3.7 hrs at 123 = 465 miles. If you plan on camping more than ~400 miles from a fuel source, then you need to consider aux fuel. But really, 400 miles from fuel?
Aux tanks add a lot of weight, a lot of complexity and are carried all the time.

Bill

[Mark Goldberg]

Bill, one builder is planning to fly his Patrol from Nome Alaska to the Tierra De Fuego on the tip of South America. He thinks there will be places where fuel is not available or very pricey. He really wanted a diesel but settled for an O360 powered Patrol.. His is the kind of scenario where it makes sense. Mark

[Bdflies]

And there I was, wondering about a practical use for more than 960 miles range. For some reason, Alaska to the South tip of South America didn’t come to mind. I really need to expand my horizons.

Bill

[James]

Bdflies - more than 400miles (600kms) without avgas????
Yep, that's about 90% of my country (Australia).
I'd love to go flying in the US or Canada, where everything's cheap, and you can get avgas all over the place.
The infrastructure in those countries is astonishing.
Or maybe I'll move to New Zealand, where you can drive anywhere in two days.
But then, why would you build a plane, when you can just drive there in a car?

Now, a great question for Aussie builders... building an experimental aircraft and designing your own fuel system doesn't exempt you from CASA pilot-in-command regulations. (When was the last time you heard of anyone flying around with a couple of jerries of avgas strapped into the back seat?)

... doesn't the FAA / TC have anything to say about that?

[Chris In Milwaukee]

I think it would also be useful in cases where you’d want to ferry fuel for others in your party. Of course, you’d have to be a really good friend to be that guy who carries all that weight on behalf of someone.

[JimParker256]

Even for the guy flying from Nome to Tierra Del Fuego, I would think a ferry tank makes more sense, because you're not going to make that flight every day. I suspect it's a once-in-a-lifetime proposition.

TurtlePac has options ranging from 10.5 gallons to well over 100 gallons. Some are designed to strap into a seat, and others are designed to lie on a flat floor with tiedowns. Others are designed to fit a float compartment. Their "Heli 21 Gallon" tank (29.5" x 26" x 8.5") would probably fit under the Patrol's rear seat. That's 21 additional gallons with a weight of 138 lbs including tank and full fuel. Or, if you don't need access to the rear seat, strap in their 25- or 30-gallon "Drum" style tank (179 and 235 lbs, respectively). All of these options have a tank weight of under 10.5 lbs, and are fully removable so you don't pay any weight penalty when you're not using them.

(And for those who just love "Jerry Cans", they have a 5.3 gallon collapsible version, with a flexible drain elbow so you don't have to lift/hold to pour the fuel into a tank.)

I'm sure there are other vendors out there as well, but this is just a company I know with a product I respect. A local pilot ferried a Grumman Traveler (O-320 power, only 37 gallons of usable fuel in the wings) to Europe using a combination of TurtlePac products strapped into the seats. He swears by them.

[Chewie]

I guess I'm in Bill's camp. Let's say the Patrol had 20 gallon tanks, then we had the option of adding aux tanks to 55 gallon total, would there still be any desire to increase it further? What sets the range that I must have? Does the feature drive the requirement? Does the solution look for a problem?
That said, I'm totally going for aux tanks. For 12,000 gallons. On the ground. No, underground. Beneath a convenient pump.

[Bdflies]

Ya know Mark, something tells me that you and I would have a hellova time with a few cold ones at a bar-b-que!

Bill