Blended Gasoline in a Cessna 152

vdehart

vdehart

Pre-takeoff checklist
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vdehart
Has anybody demonstrated this is possible? What modifications were needed and do they have a STC? The way things are headed, ethanol-free gas is becoming harder to find. Many Rotax-powered aircraft are running on standard ethanol-blended gasoline without any troubles. What is needed to convert a carbureted Lycoming engine to run on pump gasoline?
 
To my knowledge NONE of the autofuel STCs will permit *ANY* amount of ethanol in the fuel. To get your own STC would require a log of money, a DER, and a tolerant local ACO. You'd potentially need to replace some of the aluminum and rubber components in the system. Of course, you'd need to work out the manufacturing approval on those parts as well.
 
Would probably be easier to get an stc for a rotax.
 
I don't think there are any approvals for certificated aircraft to run ethanol or any blends of it.

That being said, these guys have been using it for years now, so before you take a bunch of hearsay on a forum, I'd contact them directly about any service history with it. I don't believe they have needed to change any rubber parts due to ethanol use.

http://vanguardsquadron.com/ContactUs.aspx

Also, avoid more hearsay about FAA certification, contact the STC developers themselves. about 0.1% of the forum members here have ever played any roll in any certification effort.

Two major players are

http://www.autofuelstc.com/

https://www.eaa.org/en/eaa/aviation-advocacy

The fact is, as ethanol-free gas becomes more difficult to find, these STC holders would be smart to get ahead of the game and start doing ethanol research or they may simply go out of business.

or

100LL will be eliminated and more airports will stock ethanol-free gas to offset the loss.

Or any combination thereof...


If you live in a state that requires at least some % of ethanol in all automobile dispensaries I'd call around to the local oil companies and ask who is buying and stocking ethanol-free gas, because there is likely someone who refuses to blend like a farm CO-OP or something like that.
 
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They are running injected engines NOT the 150's O-320. They are specially modified (though not necessarily for ethanol) IO-320's. In fact the Vanguard guys have BAD experience running alcohol in the carbed O-320.

Before you go around slamming other people on the forum, perhaps you should look up what the word "hearsay" means.

And since we're not taking "hearsay" let me refer you to a document of some actual research in running alternate fuels into aviation engines
http://www.tc.faa.gov/its/worldpac/techrpt/ar06-43.pdf

As stated, there is not to my knowledge any legal way to run alcohol fuels in a O-320. Neither the EAA or Petersen STCs allow it. Nobody else has STCs (in the US at least) yet. As I stated, aluminum and rubber components are going to be problematic. Fuel flows, vapor lock, etc... are all issues that even the 100% gasoline (auto) people have to fret over.
 
Ethanol free gasoline requires paperwork

E-10 requires replacement of at least the rubber fuel lines - you need the SAE spec lines (don't recall the exact grade) - the "aircraft grade" fuel lines will swell shut (according to an individual I know who had a power failure on takeoff). Other parts may or may not be an issue.

I run whatever they have at the corner gas station (I assume E-10, but never actually checked) and have aluminum tanks (and a Rotax, and SAE fuel lines) if there is a problem with the tank, I haven't seen it.
 
flyingron said:
And since we're not taking "hearsay" let me refer you to a document of some actual research in running alternate fuels into aviation engines
http://www.tc.faa.gov/its/worldpac/techrpt/ar06-43.pdf
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What does an 8 year old FAA report on "Aviation Grade E85" have to do with private entities and their pursuits?

Contact those two. If someone is trying to certify ethanol blends it might be them, or they might know who is.

http://www.autofuelstc.com/

https://www.eaa.org/en/eaa/aviation-advocacy
 
What it has to do is that it explains what the was researched on behalf of the FAA as to what the issues with ethanol blended fuel is and you can be damned sure that if you were to try to obtain an STC for an ethanol approved blend that those are issues they will want to see explained in your approval.

You seem to have no clue as to the right answers but like to throw rocks at people who do. How many STCs, PMAs, or parts have you put through the certification process? Some of us do have knowledge and relate it here.

Petersen (the first link you posted) as I have already stated is VEHEMENTLY opposed to ethanol. You can call them (if you can get through, they are not the easiest people to get tech info out of), but I can guarantee you they will tell you that they have ZERO plans to go anywhere with ethanol.

The EAA might have more info, but frankly, I they do even less with the STC than Petersen.

As stated, the O-320 hasn't a prayer of running ethanol reliably as it stands. It's been demonstrated NOT to work. Nobody I know of is working on getting an STC for these dinosaurs to run blended fuels.
 
flyingron said:
What it has to do is that it explains what the was researched on behalf of the FAA as to what the issues with ethanol blended fuel is and you can be damned sure that if you were to try to obtain an STC for an ethanol approved blend that those are issues they will want to see explained in your approval.

You seem to have no clue as to the right answers but like to throw rocks at people who do. How many STCs, PMAs, or parts have you put through the certification process? Some of us do have knowledge and relate it here.

Petersen (the first link you posted) as I have already stated is VEHEMENTLY opposed to ethanol. You can call them (if you can get through, they are not the easiest people to get tech info out of), but I can guarantee you they will tell you that they have ZERO plans to go anywhere with ethanol.

The EAA might have more info, but frankly, I they do even less with the STC than Petersen.

As stated, the O-320 hasn't a prayer of running ethanol reliably as it stands. It's been demonstrated NOT to work. Nobody I know of is working on getting an STC for these dinosaurs to run blended fuels.
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I'm sorry you feel like I'm throwing rocks. There aren't many folks on the inside of the alternative fuel circle and it acts like you are claiming to be :confused:

I'd rather talk to folks who actually worked on projects. Call SDSU in South Dakota or the aviation department at Lake Area Tech in Watertown SD. There was action up there at one time on ethanol.

152 is 0235 powered FWIW.
 
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flyingron said:
To my knowledge NONE of the autofuel STCs will permit *ANY* amount of ethanol in the fuel. To get your own STC would require a log of money, a DER, and a tolerant local ACO. You'd potentially need to replace some of the aluminum and rubber components in the system. Of course, you'd need to work out the manufacturing approval on those parts as well.
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Yup.....

You can build 20 experimentals that safely run on Ethanol for the cost of one STC for a certified plane....:yes:.......;)
 
The FAA used to be against any type of automated station transmitting on a CTAF...

Things do change.
 
An STC for Ethanol fuel has been issued. It was a long time ago, in a special program, I think at Texas State Technical college? Or some other college in Waco. It was a Cessna, but I don't recall the model or engine right now.

Ethanol is very bad as I think we all agree. I'd like to see some work done on an E-10 mix, but as has been said, it's very tough. Everything that the fuel touches has to be modified. Think about all things involved from the fuel cap and vent lines, all the way to the exhaust system. It also suffers from lower energy content which means shorter block distances for the fuel burned, or lower HP, or a combo of both.

The regulatory environment in the FAA at this point is counter to everything needed to get a blended fuel STC approved. They have no interest in meeting or even accommodating the desires of the EPA. In fact, I've heard said, and by empirical evidence there is plenty of bad blood between the two depts. Surely the FAA has reasonable and understandable concerns regarding the damage Ethanol has been shown to cause to everything it touches. I'm not a fan, but short of getting Ethanol out of the fuel supply, it would be helpful if there was even some modest work invested.

<edit: I found it. http://green.sba.gov/certification-cessna-152-100-ethanol

http://www.caddet-re.org/assets/no51.pdf

100% Ethanol Cessna 152. Plenty of gotchas along the way. AFAIK, it was never offered commercially, but I could be wrong.>
 
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There are many reasons to not run booze in your fuel.
#1 it's detrimental to the fuel system. (and has reared it's ugly head in autos as well)
#2 it absorbs water. Water is detrimental to performance.
#3 It reduces power, and increases fuel consumption. (alcohol contains way fewer BTUs than gasoline, so ya gotta burn more of it to do the same job)
#4 bein's how it absorbs water, it causes corrosion to components in the fuel system, (see #1)
#5 vapor lock could also be a concern at altitude, as could be the freezing of the absorbed water. (I've seen freezing levels quite low even here in the deep south) Which could cause trouble in flight.
You can remove the alcohol from the fuel, but it would be way cheaper to just run 100LL.
Or you can outfit your 152 to run on alcohol, but it will be experimental, and be way cheaper to just run 100LL. And you can kiss your 5-7 gph fuel burn goodbye.
10% alcohol in gasoline gives a noticable difference in fuel consumption, over straight gasoline. Enough of a difference, where you burn less gasoline, for a given period, than you burn gasoline in a 10% mix for the same period.
IOW a gallon of straight gas, will equal about a gallon and a quarter of 10% blend. (just an "off the cuff" guesstimation)
 
There is more than one regulatory agency in the world and the fuel issue is a worldwide problem. I have a hard time believing the topic is dead.
 
bnt83 said:
There is more than one regulatory agency in the world and the fuel issue is a worldwide problem. I have a hard time believing the topic is dead.
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It's not dead. However, the cost to research and develop the necessary replacement sealants, seals, O-rings, hoses, etc. to allow ethanol in Standard category aircraft, certify those materials and the parts made from them for the various aircraft out there, and then for the owners of those aircraft to pay for all the replacements in his/her fuel system seems to be beyond anything that anyone is willing to pay (or else someone would have done it already). What we do know from the existing research (including the reports cited above) is that ethanol attacks many of the standard materials used in certified aircraft fuel systems, and that should be a giant red flag for anyone considering just pouring even the slightest amount of ethanol in their fuel systems without going through that expensive certification process.
 
Certainly, an aviation engine could be developed that runs fine on car gas. Car engines run on it. So do motorcycles. But...its not as simple as it sounds. One thing a lot of people haven't thought about is the effect of all these plane owners having 500 gallon tanks on a trailer stored in their hangar. Another is if you provide the ethanol fuel at the airport, and it is less expensive, people with engines that WON'T run on it safely will surely be using it. ETC!

Having said all that, I remember being in Afton Wyoming and there was a taxiway leading up to a gas station that was on the main highway through town. You could fuel your airplane with the same gasoline they were selling to cars! Those were the days when you could get ethanol free fuel however.

Mogas on the other hand, is available at some airports, is less expensive and does NOT have alchohol and the STC's are available. In Colorado it is running about $.75 more than at the auto pump and about $.75 less than 100LL. So there is that to consider. I have "heard" that mogas is 91 octane with no additives, but I'm really not certain about that. Not certain it is the same everywhere either. Anyone know?

BTW, as you go up in altitude the need for octane to prevent pinging goes down. Once you have enough octane to prevent pinging, more octane has no advantage. Higher Octane gas has no more energy in it than lower octane gas, it just lets you run higher compression ratios without pinging.
Air at higher altitude is at a lower pressure. If it is at 30" of mercury at sea level and you compress it 10:1 then you end up with 300" of pressure inside the cylinders. If it is at 25" at 5000' and you compress it at 10:1 you end up with 250" of pressure at inside the cylinders. The higher the pressure inside the cylinder, the more the need for octane to prevent pinging.

Then there are the effects of lead. I used 100LL. I did oil analysis and there was considerable lead in my oil. Not sure if that was a problem, the engine went well beyond TBO. Data point of one on that one. The carbureted Lycoming 0-360 I had ran fine on 100LL I can tell you that.
 
bluerooster said:
There are many reasons to not run booze in your fuel.
#1 it's detrimental to the fuel system. (and has reared it's ugly head in autos as well)
#2 it absorbs water. Water is detrimental to performance.
#3 It reduces power, and increases fuel consumption. (alcohol contains way fewer BTUs than gasoline, so ya gotta burn more of it to do the same job)
#4 bein's how it absorbs water, it causes corrosion to components in the fuel system, (see #1)
#5 vapor lock could also be a concern at altitude, as could be the freezing of the absorbed water. (I've seen freezing levels quite low even here in the deep south) Which could cause trouble in flight.
You can remove the alcohol from the fuel, but it would be way cheaper to just run 100LL.
Or you can outfit your 152 to run on alcohol, but it will be experimental, and be way cheaper to just run 100LL. And you can kiss your 5-7 gph fuel burn goodbye.
10% alcohol in gasoline gives a noticable difference in fuel consumption, over straight gasoline. Enough of a difference, where you burn less gasoline, for a given period, than you burn gasoline in a 10% mix for the same period.
IOW a gallon of straight gas, will equal about a gallon and a quarter of 10% blend. (just an "off the cuff" guesstimation)
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Sort of.

#2 and #3, true, no argument.

#4 - yes, but not nearly as badly as industry would have you believe, and it's actually not really the ethanol itself (or the water) that causes the problem (see below).

#5 - sort of - vapor lock is a concern primarily during low-flow operations (ground ops, low-power descent, etc) when there is not enough cooling airflow through the cowl to prevent the fuel heating up (combination of low air flow and low fuel flow, allowing the fuel to dwell longer in the FWF area picking up heat). Vapor lock at altitude is going to be very difficult to achieve as long as you've got flying speed, though it will certainly be easier to do (by some measurable degree) with E-10 since the vapor pressure of E-10 is measurably higher. The warm fuel in the suction side of the mechanical fuel pump will vaporize during the suction stroke and the pump will inhale only vapor, which it can't pump very well at all. The result is low fuel pressure and engine stumbling which we call vapor lock.

#1 - this is the biggie - Ethanol is not really detrimental to the fuel system. Yup, that's right - ETHANOL is not - but the E10 fuel blend IS - at least for our standard aircraft fuel system in certificated aircraft. When the ethanol is added to the blend, it increases the octane number and allows the fuel manufacturer to blend different components into the base fuel stock, to keep the same final target under the ASTM. One of the components that goes up considerably in percent content in the base fuel stock is benzene - and it's this benzene that attacks all the natural rubber components in our fuel systems and WILL cause them to fail. Ethanol gets the bad rap because without ethanol we don't get the benzene content, but people never hear about the benzene. The way to avoid this problem is to eliminate all natural rubber compounds in the fuel system, from the filler cap to the engine intake valve (filler neck O-rings, fuel pump diaphragms, valve O-rings, tank bladders, quickdrain O-rings, fuel hose, carb/injector seals and rings, the whole mess) and then the system will be benzene-proof, which also makes it E-10 proof. The experimental aircraft world (and the automotive world) have already done this. I seriously doubt the certificated aircraft world ever will.
 
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docmirror said:
An STC for Ethanol fuel has been issued. It was a long time ago, in a special program, I think at Texas State Technical college? Or some other college in Waco. It was a Cessna, but I don't recall the model or engine right now.

Ethanol is very bad as I think we all agree.
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For the record I don't agree. No more than I would agree with the statement "Leaded fuel is very bad as I think we all agree."

<edit: I found it. http://green.sba.gov/certification-cessna-152-100-ethanol

http://www.caddet-re.org/assets/no51.pdf

100% Ethanol Cessna 152. Plenty of gotchas along the way. AFAIK, it was never offered commercially, but I could be wrong.>
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The following links to a PDF copy of the OSTI 677075 document that contains the full paper of the abstract referenced in your first link. According to it the use of pure ethanol in an C-152 appears to have been successful. The document is pretty much self-explanatory so I wont attempt to summarize - interested readers can read it and draw their own conclusions:

http://www.osti.gov/scitech/servlets/purl/677075
 
Jim Logajan said:
For the record I don't agree. No more than I would agree with the statement "Leaded fuel is very bad as I think we all agree."
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Meh - go ahead and put Ethanol (pure or blended) in any plane you want. Not agreeing with me doesn't bug me at all.

Ethanol fuels are bad for IC engine fuel systems not designed specifically to handle Ethanol. If you have another nit to pick, I'll stick around. ;)
 
airguy said:
One of the components that goes up considerably in percent content in the base fuel stock is benzene - and it's this benzene that attacks all the natural rubber components in our fuel systems and WILL cause them to fail. Ethanol gets the bad rap because without ethanol we don't get the benzene content, but people never hear about the benzene. The way to avoid this problem is to eliminate all natural rubber compounds in the fuel system, from the filler cap to the engine intake valve (filler neck O-rings, fuel pump diaphragms, valve O-rings, tank bladders, quickdrain O-rings, fuel hose, carb/injector seals and rings, the whole mess) and then the system will be benzene-proof, which also makes it E-10 proof. The experimental aircraft world (and the automotive world) have already done this. I seriously doubt the certificated aircraft world ever will.
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Really? Benzene has been in automotive gas for a very long time...
 
I recall my grandpa trying E10 in the Stearman once many years back as he couldn't think of where there would be an issue. Unfortunately, he failed to think about the fuel gauge, which developed a big leak quite quickly.
 
It seems like every boat motor I've bought leaks fuel big time from everywhere they can leak fuel until I rebuild them. I always suspect that ethanol is the cause of that.
 
So we have PTFE (Teflon hoses) in the engine room available from both hose manufacturers, nitrile O-rings, and cork gaskets already in the airplanes. Unless the carburetor needle is molded from super secret compound, I'm guessing it's nitrile also. (are they all metal? Been years since I've has an airplane carb apart...)

McFarlane aviation sells NAS fluorocarbon (Viton) O-rings to replace nitrile ones in fuel selector valves already. I've installed many of them.

Fluorocarbon is suitable for dynamic and static seal of o-rings in the environment containing the following chemicals: Acetylene Gas, Aluminium Flouride, Aluminium Nitrate, Aluminium Sulfate, Ammonium Carbonate, Ammonium Chloride, Ammonium Nitrate, Ammonium Persulfate Solution, Ammonium Phosphate, Ammonium Sulfate, Amyl Alcohol, Amyl Chloronaphthalene, Aniline, Animal Oil, Arachlor 1248, Argon, Aromatic Fuel 50%, Askarel Transformer Oil, ASTM Fuel A, ASTM Fuel B, ASTM Fuel C, ASTM Fuel D, ASTM Oil Four, ASTM Oil Three, ASTM Oil Two, Automatic Transmission Fluid, Beer, Benzene Sulfonic Acid, Benzoic Acid, Benzophenone, Benzyl Alcohol, Benzyl Benzoate, Benzyl Chloride, Bleach Liquor, Borax Solutions, Boric Acid, Bromine Gas, Bromobenzene, Bunker Oil, Butane, Butter, Butyl Alcohol, Calcium Carbonate, Calcium Chloride, Calcium Hydroxide, Calcium Hypochlorite, Calcium Nitrate, Calcium Sulfide, Carbolic Acid (Phenol), Carbon Disulfide, Carbon Monoxide, Carbon Tetrachloride, Carbonic Acid, Castor Oil, Tung Oil China Wood Oil, Chlordane, Chlorinated Solvents, Chlorine Dioxide, Dry Chlorine, Wet Chlorine, Chrome Plating Solution, Chromic Acid, Citric Acid, Cod Liver Oil, Coffee, Coolanol Monsanto, Corn Oil, Coal Tar Creosote, Creosylic Acid, Crude Oil (Asphalt Base), Cyclohexane, Denatured Alcohol, Dichloro-Butane, Diesel Oil, Di-ester Lubricant MIL-L-7808, Diethylamine Glycol, Dimethyl Phthalate, Diphenyl, Dow Corning 550, Dow Guard, Dowtherm A, Elco 28 Lubricant, Ethane, Ethanol, Ethyl Alcohol, Ethyl Benzene, Ethyl Benzoate, Ethyl Chloride, Ethyl Chlorocarbonate, Ethyl Formate, Ethyl Hexanol, Ethyl Oxalate, Ethyl Pentachlorobenzene, Ethyl Silicate, Ethylene, Ethylene Glycol, Ethylene Trichloride, Formaldehyde, Freon 112, Freon 114, Freon 13, Freon C318, Fuel Oil, Gallic Acid, Automotive Gasoline, Gelatine, Glucose, Glycerin, General Glycol, Petroleum Base Grease, Helium, Heptane, Hexane, Petroleum Base Hydraulic Oil, Gas Hydrobromic Acid, Hydrocyanic Acid, Hydrogen Gas, Iodine, Iso Octane, Isobutyl Alcohol, Isopropanol, Isopropyl Chloride, JP 3 MIL-J5624, JP 4 MIL-J5624, JP 6 MIL-J5624, Kerosene, Animal Fat Lard, Linsed Oil, Liquefied Petroleum Gas (LPG), Petroleum Base Lubricating Oils, Malathion, Maleic Acid, Mercuric Chloride, Mercury, Methane, Methyl Bromide, Methyl Chloride, Methyl Ether, Methyl Oleate, MIL-F-25558 (RJ-1), MIL-F-25656, MIL-G-25760, MIL-H-5606, JP-5 JP-4 JP-3 MIL-J 5624, Milk, MIL-L-25681, MIL-R-25576 (RP-1), Type 1 Fuel MIL-S-3136, MIL-S-81087, Mineral Oils, Naphtha, Naphthalene, Naphthalenic, Natural Gas, Neatsfoot Oil, Gas Nitrogen, N-Octane, N-Pentane, Oleic Acid, Oronite 8200, Oxalic Acid, Cold Oxygen, Ozone, Peanut Oil, Petroleum Oil, Phenol, Phenylhydrazine, Phosphoric Acid, Phosphoric Trichloride, Pine Oil, Potassium Nitrate, Potassium Sulfate, Producer Gas, Propane, Propanol, Propyl Alcohol, Propylene, 10E Pydraul, 540C 312F 230C Pydraul, 90E 65E 50E 30E Pydraul, Transformer Oil Pyranol, 55 (Phosphate Ester) 53 43 Pyrogard 42, Rapeseed Oil, Red Oil, RJ-1 (MIL-F-25558), RP-1 (MIL-R-25576), Sea Water, Silicone Grease, Silicone Oils, Silver Nitrate, Sodium Bicarbonate, Sodium Carbonate, Sodium Chloride, Soyabean Oil, Stearic Acid, Stoddard Solvent, Sucrose Solutions, Sulfur Chloride, Dry Sulfur Dioxide Gas, Wet Sulfur Dioxide Gas, Sulfur Trioxide, Sulfurous Acid, Tannic Acid, Tartaric Acid, Tertiary Butyl Alcohol, Tertiary Butyl Mercaptan, Tetrabromoethane, Tetrabutyl Titanate, Tetrachloroethane, Tetrachloroethylene, Tetraethyl Lead, Tetralin, Toluene, Type A Transmission Fluid, Turbine Oil, Turpentine, Varnish, Vinegar, VV-H-910, Whiskey, White Pine Tar, Xylene.​
 
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coloradobluesky said:
Certainly, an aviation engine could be developed that runs fine on car gas. Car engines run on it.
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The problem isn't whether the engine will run on autogas, but rather whether the autogas will eat the materials in the fuel system. So far, it appears based on market forces that identifying all the affected items in the fuel system of each make/model plane involved, developing/certifying ethanol-proof replacements for those items, and then buying/installing those replacements would cost more than aircraft owners are willing to pay.

IOW, "it's the economy, stupid" (W. Clinton, 1992).
 
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jesse said:
I recall my grandpa trying E10 in the Stearman once many years back as he couldn't think of where there would be an issue. Unfortunately, he failed to think about the fuel gauge, which developed a big leak quite quickly.
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Exactly the issue -- not whether the engine will run on it, but whether other components in the fuel system will be degraded by it.
 
Don't know how accurate it is but I read that Europe has a 1% maximum benzene content restriction on gasoline, in 2011 EPA restricted ours to .062%
 
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bnt83 said:
Really? Benzene has been in automotive gas for a very long time...
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Precisely - but the content varies depending on the winter/summer fuel mix and the oxygenate additive.

Current ASTM standards for automotive fuel set a maximum benzene content of .062%, down from 1% just a few years prior, and natural rubber compounds have been absent from automotive fuel systems for decades so this causes no real concern.

Avgas ASTM allows 0% benzene, and our fuel systems contain natural rubber.

See the problem yet? It doesn't take a lot of benzene to tear up natural rubber, and there's a big difference between "a little" and "none".
 
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Ron Levy said:
So far, it appears based on market forces that identifying all the affected items in the fuel system of each make/model plane involved, developing/certifying ethanol-proof replacements for those items, and then buying/installing those replacements would cost more than aircraft owners are willing to pay.

IOW, "it's the economy, stupid" (W. Clinton, 1992).
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That's part of it. The other part is that while it is certainly possible to create an alternative fuel that replace 100LL, it won't cover the ENTIRE fleet since some high-performance engines will still need the additional protection against detonation at high compression ratios (and turbocharging) that 100LL affords. Since those aircraft tend to be owned by the guys with the deepest pockets, the owners of those pockets have no desire to get behind any effort to help out the rest of us. Without some deep pocket commitment, your not likely to get manufacturers interested in risking their own skin.

This was one of the driving factors that pushed me to experimental GA years ago. That's a horsecollar that I choose not to wear.
 
airguy said:
our fuel systems contain natural rubber.
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I don't think so. Please name an example.

Nitrile and other synthetic rubbers have been around as long as gasoline and oil has.

Standard MS29513 O-rings from a 1968 Cessna 177 parts manual shows nitrile O-rings.

Many folks buy "lifetime" PTFE "Teflon" engine hoses over synthetic rubber hoses.
 
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Aeroquip 303 - An inner tube of seamless synthetic rubber is reinforced with a synthetic-impregnated single-wire braid over a single cotton braid
Aeroquip 306 A low-pressure hose for instrument air & vacuum lines. Consists of an inner tube of seamless synthetic rubber, reinforced with a single layer of cotton braid and a synthetic rubber cover
Aeroquip 601 An inner tube of seamless, specially formulated synthetic rubber reinforced with a stainless steel partial inner braid and full-coverage stainless steel outer braid. Operating temperature -65 to 300F. Aeroquip 601 hose is widely used for aircraft fuel and oil lines where flexibility and light weight are prime considerations. Because of its lighter weight and lower operating pressure than type 303 hose, it is not recommended for hydraulic lines. Use with Aeroquip 816 hose fittings. Aeroquip 601/AE701 is a direct replacement for old 601 hose. AE701 hose has no shelf life and is the upgraded version of 601 hose. Sold by the foot.
Aeroquip 666 Aeroquip 666 medium pressure Teflon hose is widely used in aircraft applications handling fuel, oils, and other fluids. It is unaffected by all fuels, oils, alcohols, coolants, or solvents commonly use in aircraft.
 
Mcfarlane Aviation has PMA'ed Viton o-rings that are supposed to outlast nitrile. I think the Cessna fuel strainer plungers are all Viton from them now.

Gates hoses recommends high quality nitriles from ethanol blended fuels.
 
Just about all the various components are AVAILABLE in nitrile or Viton, sure. But the old ones are still in the fleet - that's the reason an STC is required to change them out, or at the very least verify that they have been changed already to the proper material.
 
airguy said:
Just about all the various components are AVAILABLE in nitrile or Viton, sure. But the old ones are still in the fleet - that's the reason an STC is required to change them out, or at the very least verify that they have been changed already to the proper material.
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So when I buy an antique airplane, I won't have a problem finding new natural rubber replacement parts that are so easy to find. :rolleyes2:
 
What are we debating here? I'm not even so sure at this point. Each airplane may or may not have components that may or may not be damaged by ethanol.
 
How many manufacturers are still building airplane parts with natural rubber? US Rubber Co was building bags made of nitrile in 1946. The natural rubber argument is very very weak. I'd bet there isn't a parts supplier even using natural rubber anymore for aircraft.

http://www.eaglefuelcells.com/ga/repair.html

US Rubber / AmFuel (multi-ply nitrile) Repairable? 1946-55 US-538N Durable military construction becomes stiff with age Sometimes 1956-on US-566R Durable military construction Usually 1956-59 US-584 Nitrile coated cotton fabric, dries out, shrinks, and tears Not worth it 1956-61 US-588 Durable military construction Usually 1959-62 US-907 Extremely thin material No
 
jesse said:
What are we debating here? I'm not even so sure at this point. Each airplane may or may not have components that may or may not be damaged by ethanol.
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You know how it is.

:lol:

The aircraft we normally talk about here were built with synthetics. They were making nitrile bladders in 1940's... It's not a "new" thing. Nitrile is recommended by Gates for ethanol blends.
 
If someone wants to replicate the mods and the tests that Baylor Waco did, I suppose they can get the STC. I would gauge, just by SWAG that the mods and the test would come in around $5 AMU with the owner helping out. Then, you can go run all the Ethanol you want as long as it's pure Ethanol.

Since you're going to need prolly 8-9GPH to feed the engine for the same job, and the cost of the pure fuel is going to be maybe $10/gal I don't see the point. One would need an STC for blended fuel. I'm guessing the mods and tests would be similar, and then you have the question of whether the FAA is going to sign off. I'd like to do the work, but I don't have a C152 handy, and sure as heck I'm not going to try it on my Bo.

But - for the enterprising mat sci or mech engineer out there with a passion for aviation, I would applaud anyone working on this goal. Use the Baylor Waco study and approval as your source material and have at it. Make up a kit for each airframe, start with the 152, then the 150, then the 172s, AA5s, Cher 140/160/180, etc.

Do it and the flying public will beat a path to your door.
 
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