Sport Pilot Talk

eidolon45 · Joined: 25 Dec 2010 Posts: 56 Location: fairfax, va

As a fairly new flyer among the light sport community, I am increasingly wondering why FBOs don't have automotive fuel available for those planes that can use it. Most Light Sport planes as well as some conventional can now usew the cheaper stuff, yet I have not seen it available at a single airport. Our little airport in eastern MD has a school with a fleet of about 8 Rotax equipped Light Sports which seem to use most of the airport LL100 stock every day. Not only do we have to fill up with the higher priced stuff, but we also have to use an addative to keep the lead from gunking the engines. I know Ethenol is considered a problem for aviation, but I have also heard that some newer aviation engines can tolerate ethenol? Anyone got professional knowledge on this topic?

Jim Stewart · Joined: 12 Oct 2006 Posts: 259

I think it's economics. Installing a new fuel delivery system is expensive, what with all the environmental considerations. Us Rotax 912 users are very small fish. We only burn 3-4 gallons an hour and there are not that many of us. Contrast that to all the engines out there burning 10-20 gallons an hour and you can see that our business isn't that much.

As to the ethanol issue, the 912 will happily burn 10% ethanol. Your plane's fuel system may be another matter. You have to check the specifics.

Carrying two 5 gallon jerry cans to the airport and filling up your plane periodically isn't really that big of a deal. That's what most of us do.

FastEddieB · Joined: 07 Jan 2009 Posts: 207 Location: Mineral Bluff, GA

Quote: Most Light Sport planes as well as some conventional can now usew the cheaper stuff, yet I have not seen it available at a single airport...

There are a few. You can go to Airnav.com and do a fuel search specifying MOGAS.

Last I checked there were a few around, but not many.

The only way the economics could be overcome was to make a small airport a "draw" for LSA activity. Copperhill, TN is getting 100LL and 10 new hangars, many of which have ROTAX-powered planes. I asked for a MOGAS pump, but its not economically feasible, with most owners just carrying cans for local flights and putting up with 100LL when they're on cross-countries (unless they have friends that can meet them).

Maybe this will change someday, but I'm not holding my breath!

eidolon45 · Joined: 25 Dec 2010 Posts: 56 Location: fairfax, va

interesting replys. I was not aware that quite a few owners seem to bring their own fuel in 5 gal cans. I guess that's ok as long as you bring in good, non-contaminated stuff. I suspect there may not be a big push for automotive fuel since we need to subsidize 100 LL for the rest of the GA flyers?

My math indicates you could save 25 to 35 $ per fill-up by hauling your own gas. Any aviation suppliers specialize in small portable tanks that have extra filters for water, whatever? Marine industry has been on top of this issue for years.

FastEddieB · Joined: 07 Jan 2009 Posts: 207 Location: Mineral Bluff, GA

I just use a combination of 5 gal and 2 1/2 gal plastic cans. It really seems to be what everyone with a ROTAX does around here.

My Sky Arrow came with a funnel/filter that I use whenever I use auto gas.

(stock photo I just Googled)

I sometimes find tiny bubbles of water in the bottom of my sampler cup, but not enough to be alarmed about. I normally park the plane with about half-tank or less, in case I need to take a heavier passenger up some time. That might help account for some of the water due to condensation.

Cub flyer · Joined: 10 Sep 2006 Posts: 593

We used nothing but autogas in the flight school from 1985 until 2007. Almost all in 5 gallon cans. I would fill the pickup with 10 cans and drive to the gas station at the airport entrance. Fill up and return. Several times each day. It ran fine as long as you did not leave it in the tank for a long time. TBO and beyond easily.

When the ethanol showed up the problems followed.

Leaking quick drains, leaking carbs, hoses swelled shut, fuel valve problems, water. The Mil 6000 hose would swell shut like a heart patient. Coating inside the kitfox fuel tanks peeled off, My X air tank the fuel burned right through the seams, gel looking stuff out of the low points. It varies depending on location and state what you get in the fuel.

I had to install an above ground 100 LL tank.

Now we are watching the 100 LL and see changes. Yellow stains similar to car gas under the quick drains, different smell to the fuel. I think the formula is slowly changing. It runs ok so far but I had a very hard time convincing the FAA that there was no car gas in an airplane with yellow stains after a recent accident. Fuel was blue but yellow stains?

I'd like to try the Swift fuels.

Try Northern Hydraulics. I think they have mobile tanks and pumps that are reasonably priced to ship. Makeup a small 30 gallon tank and pump with filter and you are all set.

eidolon45 · Joined: 25 Dec 2010 Posts: 56 Location: fairfax, va

Thanks, Cub Flyer. Did the FAA seem to have a problem with using automotive fuel?

Cub flyer · Joined: 10 Sep 2006 Posts: 593

I have a mix of EAA and Peterson Autogas STC's. From the J-3 with A-65 (65 hp) to the Beech 18 with R-985 (450 hp) The STC basically is invalid once ethanol is involved.

Once Ethanol showed up we experimented with the homebuilts and had trouble. Mainly with gas from NY state. Local gas, there were a couple stations you could get without ethanol last year but that's mostly gone. There are a couple not marked but I don't trust them.

I think it won't be long before we see ethanol compatible kits for the autogas STC holders. There are some blue seals and carb floats being used already in quick drains and other components. I've also seen illegal installations of NAPA fuel line (PVC Hose) for the short hoses that connect the wing tanks to the fuselage on high wing airplanes. Worked.

If you are running a homebuilt don't let your mechanic replace the original "lawnmower" tygon fuel tubing with "aircraft" MIL 6000 hose. I did and the engine failed on takeoff. Stay with the tygon until a better solution comes around. (teflon stainless braid?)

Biggest thing is don't let it sit more than a few weeks in the tank. High test seems to go bad faster than cheap stuff. No scientific testing just an observation.

Cub flyer · Joined: 10 Sep 2006 Posts: 593

Now that I'm not lifting all those cans I need to exercise.

Jack Tyler · Posted: Wed Dec 29, 2010 8:12 am Post subject:

eidolon45:

Some GA aircraft, long before the LSA rules came along, have been approved for autofuel for many years. Consequently, bringing fuel to the plane from out in town is a well-known part of the aviation lifestyle for lots of folks...and so there are lots of views on how to do it. E.g. the EAA and AOPA have both published many an article and crib sheet on this topic; you might want to research this with either of them.

Not that this is how you 'should' do it but, after researching this for our Grumman AA-5 (which was STC'd for autofuel), this is what we ended up doing:
-- Picked up a large 10 gal. plastic fuel tank with integral fuel gauge, intended for marine use, from West Marine
-- Put together an inexpensive 12V pump (cheap auto fuel pump) with a cigarette plug on the end of the wire and plastic tubing (short on the tank side of the pump; longer on the output side of the pump)
-- Added a separate ground wire on the pump, which was attached to the plane's muffler just like the fuel truck guy does when he fills your plane
-- I chose not to bother with an in-line filter since I could look in the plastic tank with each fill-up to determine if there were bits that needed filtering; there are a variety of very cheap in-line filter options available that are intended for use with small boats' outboards

For the more typical currency or local flights, our 8 gph burn rate usually meant that one tank fill, on the way to the airport (who wants to be driving around town with a bomb in the back of the car?), was enough to top up what had been used during the last flight. This involved no lugging (I am w-a-y too familiar with lugging fuel in 5 gal jugs, as I'm a sailor) and topping the plane's tanks was very easy BUT did require that we could drive right up to the plane. Otherwise the plane would have to be moved to where you can get your car, which would be inconvenient. When the tank was in the car's trunk, the vent on the tank was closed; not a problem whether the tank was full or empty and standard practice on boats carrying jugs on deck despite what one might think the vent is for. After the fill-up and when we returned home, the tank was easily removed from the car as it was empty.

We used this method for 5 years. The tank/pump/tubing/wire was paid for in the first few months AND we were burning a cleaner fuel than 100LL for our Lycoming engine.

However, pay attention to Cub Flyer's description of what he found once he used gas with Ethanol (something we never had to worry about). Even if your engine mfgr. now says their engine can run E-10 fuel (e.g. Rotax makes that claim) that may not apply to your (earlier built) engine; call them and discuss it. The next step is to talk with the airframe mfgr. about this, as the tank, tank components and fuel system may not be fully compatible. (LOTS of info on this topic if you google a bit...) If you've got the OK from both mfgrs., consider you still might have problems - in which case, you want to shop for non-E10 fuel sources. E.g. marinas sell gas without E-10 - they are exempt, or at least are allowed to be, if they choose. There is also a nicely-built & updated data base of non-E10 fuel sources, by state, that you can consult, which I found via the bydanjohnson.com website. Google produces a zillion hits on this topic, but the data base being kept current is very helpful. Sorry I don't have the URL handy...

GOG376 · Joined: 17 Jan 2007 Posts: 5

Check with the collector car people on available E-free fuel.
GOG

FastEddieB · Joined: 07 Jan 2009 Posts: 207 Location: Mineral Bluff, GA

http://pure-gas.org/

Cub flyer · Joined: 10 Sep 2006 Posts: 593

Thats great. The guy who owns the local Drifter has been bringing gas from the West Pittston station. I see it's on the site.

eidolon45 · Joined: 25 Dec 2010 Posts: 56 Location: fairfax, va

Thanks to everyone for the useful information and web sites. I'm a little surprised the aviation industry seems to be having so much trouble with the ethenol issue. The marine industry developed ways to manage the problem over a decade ago. Engine fires are the critical concern with the gas inboard users. Exploding engine compartment while underway is probably about as exciting as engine failure on takeoff. Coast guard was quick to mandate special carb, fuel pump components and ethenol resistant hoses to head off the problem. I had to replace some of these things on my boat. Not all marinas sell ethenol free gas anymore and their stuff is pretty expensive to boot.