FAA could solve mogas confusion

My co-author, Kent Misegades, recently wrote an article about the confusion of some in airport management about allowing mogas operations on an airport. Sad to say, it isn’t just a few airport managers. There is widespread ignorance about mogas use in aviation that permeates the FAA bureaucracy, the aviation alphabets, aviation media, state aviation departments and especially the auto gasoline industry.

What is ironic is the myths, misinformation and disinformation could be completely alleviated if the FAA would issue an AC or SAIB making it clear that auto fuel specified by ASTM D4814, without ethanol, is an approved fuel for aviation use.

The FAA granted approval in 1982 through the STC process and approval is now being granted by numerous new aircraft engine manufacturers, LSA manufacturers, and it is widely specified by homebuilders. In fact, mogas is the recommended fuel for the Rotax series of engines and there are new versions of Lycoming and Continental engines that allow its use.

Unfortunately if you looked at gasoline producers’ web sites (and here) you would think that auto fuel can never be used in aviation, even though it is sold on more than 110 airports in the U.S. and has been used for three decades.

When Oregon passed a state mandatory E10 law in 2007, with no exceptions for aviation, marine, antique cars and small engines — something no other mandatory E10 state did — pilots contacted the Oregon Department of Aviation and questioned how that happened. Turns out the acting head of the department was a non-pilot bureaucrat who admitted he didn’t know auto fuel was approved for use in STC’d aircraft, LSA and homebuilts so he didn’t object to the bill when queried by the legislature.

During hearings to pass a bill to grant the necessary exceptions for aviation, marine and small engine use, the president of the Oregon Airport Management Association was dumbfounded when he learned pilots could self fuel their aircraft and bring auto fuel on the airport to accomplish that end. He stood in front of the DOA manager and stated they should work on legislation to prohibit that, until I pointed out that it is a pilot’s right to self fuel with mogas as spelled out in FAA A/C 150/5190 which is now in its sixth revision. States cannot abrogate that right, nor can any public use airport that has accepted federal funds.

The FAA currently, obliquely, pays lip service to the fact that mogas is approved as an aviation fuel. It has issued an SAIB CE-07-06 that warns pilots of the danger of using ethanol blended auto fuel, which is prohibited by every mogas STC.

If you don’t want to look it up, here is key verbiage in the SAIB, “Fuels have to conform to a specification in order to be approved for use in type certificated aircraft. The American Society for Testing and Materials (ASTM) developed specifications for automobile gasoline as well as aviation gasoline. These specifications are ASTM D 910 and ASTM D 6227 for aviation gasoline and ASTM D 439 or ASTM D 4814 (latest revision) for automobile gasoline.”

So, now you know, auto fuel conforming to ASTM D4814 is approved aviation fuel and the FAA says so … obliquely.

All of the confusion, especially the confusion in Texas, could be eliminated if the FAA plainly stated in an A/C or SAIB that auto fuel conforming to ASTM D4814 is an approved fuel for aviation use in aircraft with mogas STCs or certified by the LSA manufacturer or the EAB manufacturer and cannot be prohibited from being sold on any public use airport that has accepted FAA funding.

Such a statement would put gasoline producers on notice that putting misinformation and disinformation on their websites should cease, and the EPA should be on notice that the disappearance of ethanol free auto fuel will be an economic disaster for general aviation.

Which is even more ironic when you consider that the EPA is under continual badgering to get rid of leaded avgas and lawsuits fly endlessly in California, arguably the largest aviation gasoline market in the country, to prohibit it. In addition, California has lead fouled airports that could be forced to curtail operations. Yet, those airports could be selling unleaded fuel for most of the GA aircraft today, but the airport manager doesn’t have a clue that mogas is approved for aviation use.

Just as A/C 150/5190 clarified the confusion over the rights of pilots to self fuel their aircraft when I was confronted by state aviation authorities who thought there should be state laws to prohibit mogas self fueling on public use airports, it would clear up the confusion in Texas and California if the FAA had a similar A/C or SAIB that clearly stated that mogas is approved for use as an aviation fuel in the more than 60,000 GA aircraft that have mogas STCs, and thousands of LSA and homebuilt aircraft. Then we could counter the myths, misinformation and disinformation put out by the auto fuel producers, some of the aviation alphabets and aviation media that pass on the misinformation without checking the facts and the myriad of bureaucrats we face in the state and federal government that are clueless.

And maybe, just maybe, the airports in California could install mogas infrastructure and show the EPA and the plaintiffs in the anti-TEL lawsuits that GA is serious about reducing the use of leaded aviation fuel in the thousands of aircraft that don’t need it.

So what do you say, FAA, can you help us out here with one piece of paper that would dispel the confusion about mogas once and for all?

By Dean Billing


  1. says

    My FBO would be very happy if you did your own fueling. Most LSA hold 25 gallons. Most often planes never use more than 75% of their fuel before re-filling. That is 19 gallons of fuel. If you want to lug four 5 gal cans of fuel from your truck to your plane this FBO would love it as selling 19 gals into two tanks takes a fair amount of labor that could be used to fill a Jet that needs a few hundred gallons.
    It is to the FBOs advantage to not have to mess with such small orders. Buy the crew some donuts, they will be glad to see you.

  2. says

    Thanks for the info everyone. I attended a seminar where the idea of 100% ethanol fuel could be used for aviation without degrading any components or decreasing power output. The mixture of gas and ethanol is where the problems develop. It appears it is not possible to produce this with current technologies, but I would love to hear everyone’s analysis of this possibility, if you would not mind commenting?

    • says

      Steve – Technically easy … prohibitively expensive. It only requires a new engine with a very high compression ratio, almost a diesel. So why not use a diesel? They burn Jet-A which is ubiquitous on airports worldwide, which is exactly why every airplane engine manufacturer is working on one right now. Now, add the cost of developing and certifying the new engine with certifying every new airframe your going to put the engine in, because your not going to put E100 in any existing airframe, and then install new fueling infrastructure at all the airports we can’t even convince to install a pump for mogas which can be used by 60,000 airplanes today with mogas STC’s and every LSA. Somehow, I’m not grasping why anyone is even considering this idea. Heck we have an RFS mandate that was supposed to produce copious amounts of E-85 for cars and we can’t afford the infrastructure upgrades for car service stations, so we get E10 in every drop of gasoline produced in the country and pretty soon there won’t be any E0 produced for aviation use.

      • says

        E0? Sorry what is that?
        Ethanol is only benefiting corn farmers, not the environment or us suckers who are forced to put it in our cars. Do cars not have same degradation issues with ethanol, plastic and rubber parts?

        • says

          When referring to ethanol blended gasoline Enn, where nn is always a number, refers to the blending level. So, E0 means no ethanol blending, i.e. 0%, E10 means gasoline that is 10% ethanol, E85 which can be used in flex-fuel vehicles means gasoline that is 85% ethanol, 15% dead dinosaur parts.

          Unblended gasoline, E0 is the only kind approved for aviation use in STC’d aircraft and the only kind found on the 110+ airports that pump mogas as referred to in my post above.

          Absolutely YES! Cars have the same degradation issues with ethanol, especially if they are made before about 1986 or so. This is why every state that has passed a mandatory E10 law for auto fuel has an exception in the law for classic and antique cars, aviation and marine use and small engines. Of course not one of those state laws requires that any E0 gasoline be produced and made available to the people who must have it, including your public safety services, so when the RFS mandate in EISA 2007 requires that every drop of gasoline produced in the U.S. have ethanol in it, we might just have a small problem, Houston. If you want to understand the dilemma, see http://www.e0pc.com

          • says

            I thought so but first time I saw E0 which is Mogas. Thanks for the link. Actually, I had to take an extra blood pressure pill.
            OMG! I cannot believe how the EPA has such total disregard for the costs associated with these ridiculous changes. E15? Mitigation plans to protect against lawsuits from misfueling and more costs to the gas stations to comply. Separate dispensers for E-10 or lower not for use in passenger cars. Read this guys….This is a ploy by companies that make dispensing units, corn famers and ethanol plants to bankrupt the struggling public. And for what benefit? Clean Air that in reality when you take into account all factors pollutes the air even more.
            It is no wonder the average American is getting beat up financially. The government hands out food stamps like Skittles and then forces these same people to pay more for gas to get them to the store to buy food that cost more because corn prices are higher. STOP THIS MADNESS!

  3. Dan says

    I have an additional concern. Even with what FAA A/C 150/5190 states, in researching this matter myself previously, I have come across documentation consisting of minimum standards, so called “self fueling permits” and various communications generated at a considerable number of airports around the country which appear to be putting in place processes or criteria which, from a practical standpoint, result in a prohibition on self fueling by the very fact of what I consider to be the imposition of unreasonable requirements in order to be able to self fuel.

    As an example, a number of airports have minimum standards put in place which cover self fuelers requiring a minimum size of storage tank or fuel truck which is unrealistic for the largest percentage of aircraft owners in the country.

    I am confused as to whether the FAA is allowing such requirements or if it is just a case of people not challenging these requirements which appear to violate the FAA standard. Either way my analysis leads me to conclude where such restrictions are in place the vast majority or all of the potential “self fuelers” are unable to meet such onerous requirements. Any insight in this related issue?

    • Edd Weninger says

      I’ll refer you to the 2nd paragraph in my comment below.

      The owner/operator/manager can stipulate what conditions must be met in order to do self-refueling or ramp maintenance. To do so, and meet the various airport/municipality/state/federal requirements, etc. There are a lot of hoops to jump through. And the airport can, an do, require this legally in compliance with the FAA A/C.

      And, even if you meet the safety/environmental, etc. requirments, the real kicker is Liability Insurance. Most airports inSoCal , if not all, require proof of Liability Insurance to tie-down or rent a hangar. Requiring additional insurance for self-fueling seems reasonable to me.

      If you had the spot next to me, and you had an accident refueling and damaged my plane, I would like you to have insurance to cover my loss. If the airport did not require it, they would be liable. They would rather not be.

      Again, I say the author is misreading the FAA A/C. It says, yes you can self-fuel, but it also says it has to be done within reasonable expectations of complying with safety and environmental regulations.

      • Dan says


        As you state “Again, I say the author is misreading the FAA A/C. It says, yes you can self-fuel, but it also says it has to be done within reasonable expectations of complying with safety and environmental regulations.”

        Therein lies my point. AC 150/5190-6 in providing further guidance on the issue of regulations provides in Section 1.3(a)(2) “Any unreasonable restriction imposed on the owners or operators of aircraft regarding the servicing of their own aircraft may be construed as an exclusive rights violation.”

        Section 1.3(a)(2)(1) further provides “Restrictions imposed by an airport sponsor that have the effect of channeling self-service activities to a commercial aeronautical service provider may be an exclusive rights violation.”

        My research on the subject leads me to believe that depending on a party’s point of view, many restrictions imposed by airports across the county are in fact unreasonable, and it could be argued, are put in place to discourage or eliminate the ability of an aircraft owner to self-service their aircraft and therefore have the effect of channeling self-service activities to a commercial aeronautical service provider.

        A case in point, Collin County Airport Development Corporation (“CCADC”), McKinney, Texas, prepared a white paper addressing self-fueling by aircraft owners. In that white paper the following statement is made, “The aforementioned requirements are stringent enough to discourage self-fueling by small operators but not by large-volume operators (e.g. corporate flight departments) who are economically able to meet them. To further tighten the reigns on self-fueling and generate more revenue from it CCADC could establish a two-tiered fuel flowage fee and minimum use requirements . . . ”

        Now I am not sure how you interpret the above, but to me at least it would appear the regulations and requirements are being put in place not for safety, etc. but rather to discourage or eliminate the ability of aircraft owners to self-service and force them to use a commercial aeronautical service provider.

        I again ask the question, is the FAA is allowing such requirements in apparent contradiction to AC 150/5190-6 or are such restrictions the result of aircraft owners not legally challenging these requirements which appear to violate the FAA standard?

        • says

          This is the key: AC 150/5190-6 in providing further guidance on the issue of regulations provides in Section 1.3(a)(2) “Any unreasonable restriction imposed on the owners or operators of aircraft regarding the servicing of their own aircraft may be construed as an exclusive rights violation.”

          If mogas is not provided on the airport, it is the right of a pilot to bring mogas onto the airport to fuel their own aircraft. If they are restricted from doing so it can be “construed as an exclusive rights violation” and the pilot can file a complaint with the FAA and it will be taken seriously. Obviously insurance requirements must be met, but they can’t be oppressive and as long as the containers or fueling trailer is legal for flammable liquids and the pilot fuels the aircraft in the same manner as an airport commercial fuel truck would, then there should be no problem. On a large airport here in Oregon, I was required to have liability that covered the airport just to have the hangar, nothing additional for self fueling, and I had to refuel my aircraft the same way the local fuel truck would, airplane at least 25 feet from my hangar or any other aircraft. Restrictions must be fair and sensible and equally applied.

        • Edd Weninger says

          “…..Therein lies my point. AC 150/5190-6 in providing further guidance on the issue of regulations provides in Section 1.3(a)(2) “Any unreasonable restriction imposed on the owners or operators of aircraft regarding the servicing of their own aircraft may be construed as an exclusive rights violation.”

          Section 1.3(a)(2)(1) further provides “Restrictions imposed by an airport sponsor that have the effect of channeling self-service activities to a commercial aeronautical service provider may be an exclusive rights violation…..”

          Exactly! What is reasonable? What is unreasonable?

          State, County and Cities that own the airports determine the requirements. If the requirements are to meet all EPA regulations, Fire safety regulations and probably dozens of others, and carry enough liability insurance to indemnify the airport they are considered reasonable. The FBOs do meet these requirements, so again they are considered reasonable.

          This has already been argued in court years ago. The argument was there was only one provider of avgas at the airport. An business entity claimed he was not allowed to provide avgas because the airport wanted to protect the existing FBO. The judge ruled in favor of the plaintiff, saying if he met the same requirements, he was entitled to start a business.

          Note: the requirement to meet all Fed, State, County and municipal safety and environmental regulation was considered reasonable. A NewCo would have to meet them, and provide the same insurance requirements. The right to provide services was not abrogated.

          Dean, this also applies to your argument.

          As an airplane owner, aren’t you required to have Liability Insurance?

          As an aside, one can find E0 in Cal at some marinas.

          • says

            Edd – “A NewCo would have to meet them, and provide the same insurance requirements.” I think you are talking about a commercial operation here, “NewCo”? I am not talking about a commercial operation, only an individual fueling their own aircraft.

            “As an airplane owner, aren’t you required to have Liability Insurance?” Yes, I don’t contest this. As I stated above I had to have liability insurance to rent the hangar whether I self fueled or not. Self fueling should make no difference. If there is a separate insurance requirement that results in restricting your ability to self fuel, I would contact the FAA, referring to AC 150/5190-6 Section 1.3(a)(2)(1) as noted above.

            “As an aside, one can find E0 in Cal at some marinas.”

            If that is true, I urge you to list them on pure-gas.org The only E0 that I am aware of is in Northern CA from one distributor, Renner Petroleum, and is primarily for marine use mainly sold at fishing stores at ridiculous prices in very small quantities.

          • Dan says


            I am an attorney who has been researching this issue for a client in anticipation this issue may arise at the local airport where my client operates. I can tell you that my extensive review of numerous minimum standards, rules and regulations, and self-fueling permit procedures across the U.S. does not lead me to believe that potential self-fuelers run into issues with complying with all the various local, state and federal safety and environmental regulations. They would legally have to comply with these whether or not the local airport sponsor listed them as a requirement in the self-service process.

            The “rules and regulations” which cause the problems are those such as the following examples:

            1. Requiring a self-fueler to own or lease a fuel tank of not less than 10,000 gallons.
            2. Requiring a fuel truck with not less than 750 gallons of capacity.
            3. Requiring a minimum use of xxx,xxx gallons of fuel per year.
            4. Requiring equipment capable of bottom loading when all that is needed is over the wing capability.
            5. Requiring the payment of a fuel flow fee which is two to three times that of the fee charged to commercial operators.

            I will say it again, “rules and regulations” such as the examples above are not put in place for safety and environmental reasons but rather to discourage or eliminate the ability of aircraft owners to self-service and force them to use a commercial aeronautical service provider. This is a violation of FAA grant assurances, and in my opinion, if challenged, could jeopardize the past and future federal funding of airports utilizing such tactics.

          • says

            Dan – I believe we are talking about two entirely different issues. It appears you are talking about adding a self service fuel operation on an airport, perhaps one that sells mogas. My post was in reference to an individual pilot who wants to bring a small quantity of mogas onto an airport and fuel his own airplane because the airport does not provide the fuel that his aircraft requires and A/C 150/5190 clarifies his right to do that.

            Like A/C 150/5190, I would like the FAA to clarify in a single document that mogas is an approved fuel for aviation use. They do that obliquely in SAIB CE-07-06, but apparently that is confusing to some airport managers, some in the aviation media and the aviation alphabets and the SAIB is unknown to the bureaucrats in state aviation departments, at least the ones here in Oregon, and to a number of them in the FAA. And I want it to use it to quell the disinformation put out by gasoline producers and to try to make the EPA understand that the RFS mandate is going to make one of our two aviation gasoline fuels extinct very soon, at just about the same time TEL disappears.

          • says

            Edd – I should have included an additional comment.

            “Exactly! What is reasonable? What is unreasonable?”

            “Reasonable” for an individual self fueling their aircraft with a fuel that is not available on the airport but is approved for aviation use by the FAA or the manufacturer in the case of an LSA or homebuilt are regulations that don’t make it impossible to fuel your aircraft. I think we have covered insurance. If the airport requires the fuel to be in containers that are approved for flammable liquids, that’s reasonable. Don’t pull up with a trailer or truck bed tank full of gasoline in a tank that is only rated for combustible, i.e. diesel. If the airport requires you to fuel your aircraft a certain distance away from other aircraft and infrastructure, that is reasonable. If they require a certain kind of fire extinguisher be present and usable, that’s reasonable. But if they have some obscure or ridiculously expensive requirement that you can’t possibly meet, challenge them, refer to the A/C and tell them your calling the FAA.

            And lets be realistic. In this day and age, considering the economic disaster that GA is, why would any airport want to hassle a single pilot trying to refuel his little airplane with mogas? And how many airport personnel, that know the regulations and the A/C, are cruising the airport looking for the renegade pilot refueling his airplane to bust? I self fueled my C-172 at the busiest airport in central Oregon for two years and never ran into any airport personnel. They were too busy dealing with ever changing TSA hassles. They were more interested in whether I waited to make sure the remote gate closed without letting another vehicle in than if I was self fueling my airplane. Really! And the FBO’s didn’t give a rip, they were hoping that another biz-jet would come in and buy 1000 gallons of Jet-A. They even wished they could get rid of the 100 LL tank. They had the price of 100 LL jacked up so high that the small plane transients went to the other two airports in the area.

            So that’s reasonable to me. Your experience may vary.

          • Dan says


            Actually we are talking about the same thing. I have a client who desires to self-fuel his two aircraft by bringing mogas to the airport rather than having to purchase it from the current FBO. While the issue was initially raised by a member of the airport board where my client’s aircraft are based, for now it was decided no action would be taken. We are however preparing in case this matter should arise again.

            In researching this issue, the examples I provided you above are real life examples taken from rules, regulations and minimum standards which exist at various airports that would apply to non-commercial operators regardless of whether the aircraft operator is a corporate flight department which burns hundreds of thousands of gallons of Jet A per year or a private pilot who uses his/her aircraft for recreation and maybe burns 1000 gallons a year or less of mogas if they are lucky.

            In order to be allowed to self-fuel, some of the regulations at some airports would require compliance with the examples I gave above regardless of the fact that an aircraft owner may only have the need to bring a limited quantity of fuel to the airport on an occasional basis. Thus my point that some of the “rules and regulations” being put in place are clearly for the purpose of discouraging or eliminating the ability of aircraft owners to self-fuel and force them to use a commercial aeronautical service provider.

            We are talking about the same issue and I believe we are on the same page.

          • says

            Dan – Interesting. Other than inconvenience, perhaps because the vendor is closed, why would your client not want to purchase his mogas from and FBO enlightened enough to provide mogas on an airport. I can think of a lot of important reasons that he would want to support the business … and perhaps a few that he wouldn’t, but my pros outweigh my cons. If you want, PM me at dean@flyunleaded.com because I would like to continue the conversation and this is probably not pertinent to the blog.

          • Kent Misegades says

            As co-author of this blog, but also past president of one of the largest EAA chapters in the country and as head of aviation sales for a major fuel equipment maker, I thought I’d make a few observations. I review minimum standards and fuel-related regulations from all across the country as part of my business. California is by far the most restrictive. Airports in the Southeast the least. While regulations concerning fuel equipment is fairly consistent, minimum standards vary widely, even within a given state. I rarely come across an airport that objects to self-fueling of small volumes of fuel, unless we’re dealing with light aircraft on airports that serve airlines or have some other reason for TSA and the many restrictions that come with it, such as not being allowed to drive a private vehicle up to your airplane. Most minimum standards require fuel sellers to provide extensive facilities, which makes it hard to compete for a fuel-only business. I have no doubt that these standards are written primarily to restrict competition and protect preferred FBOs. More recently my business has been selling small Jet-A fuel systems to corporate aircraft owners looking to save money. This is where one finds the greatest resistance to self-fueling, as FBOs sell far more Jet-A than other fuels. If an airport is too restrictive however, they risk losing turbine aircraft and the property tax that comes with it. I suspect that in many cases, the piston plane owner that self fuels from two 5 gallon jugs once a month is caught by restrictions intended to force a CJ or TBM owner to buy fuel from his FBO. It is doubtful that objections to self-fueling are related to safety and liability concerns. About 1/3rd of all airports have self-service fuel stations these days with only simple operational instructions. Problems during self-fueling from these are near non-existent.

        • Dan says


          I will continue the conversation with you directly but just wanted to make one last point. The right to self-service is provided regardless whether a particular service on an airport is provided by a commercial entity or airport sponsor and includes the right to tie down, adjust, repair, refuel, clean, and otherwise service his/her own aircraft.

          So in this case while the local FBO is enlightened and has provided mogas for years, it is frankly an issue of significant difference in cost for my client and he still uses the FBO for other services.

  4. Edd Weninger says

    You are misreading the FAA A/C 150/5190. You will note there are various exclusions for safety, environmental, OHSA, etc. reasons.

    Out here in SoCal, I do not know of one airport that will allow self-fueling by a pilot. And, at most airports, ramp maintenance is not permitted either……..Unless you comply with ALL the applying safety, environmental, OHSA, et al, regulations. In addition, if you do comply with the regs you will need proof of liability insurance in the amounts the airport owners deem appropriate.

    • says

      I do not believe I’m misreading FAA A/C 150/5190. Todd Petersen provided the following clarification of my understanding:

      From AC 150/5190-6 1/4/2007 :

      2. Restrictions on Self-Service. An aircraft owner or operator may tie down, adjust, repair, refuel, clean, and otherwise service his/her own aircraft, provided the service is performed by the aircraft owner/operator or his/her employees with resources supplied by the aircraft owner or operator. Moreover, the service must be conducted in accordance with reasonable rules, regulations or standards established by the airport sponsor. Any unreasonable restriction imposed on the owners or operators of aircraft regarding the servicing of their own aircraft may be construed as an exclusive rights violation. In accordance with the FAA grant assurances:

      Todd’s comment: “Looks pretty clear that one may refuel his own airplane. I have heard in the past that sometimes the local Fire Marshall, in conjunction with a bent out of shape FBO, will try to stop it by creating hoops for the individual to jump through, but have never heard that doing so actually worked long term. When people have fought it as far as I know, they’ve won. Usually airport boards come through for the individual rather than taking a chance on losing Federal funding.”

      Actually your argument concerning Southern California is moot. There is no E0 in California to haul to the airport. About the only people who could be self fueling are ultralights and those few LSA that allow E10.

    • Neil Rubin says

      Santa Monica Airport allows self fueling. The right to self fuel is even recognized in the municipal code:

      “ Fueling operations.
      . . .
      (a) The right of a pilot to fuel his or her own aircraft pursuant to Federal law shall be respected. . . .”

      There is even a flight school on the field that fuels its own Rotax-powered LSAs using mogas.

      • Edd Weninger says

        Every airport in California that receives federal funds must comply with AC 150/5190-6 1/4/2007. However, note below. The airport can require reasonable safety issues be considered, e.g., there might be a requirement for Cal OSHA regulations be complied with; that liability insurance be in place, hold-harmless agreement, etc. Ask Santa Monica what the requirements are for an individual based at SMO to fuel their plane.

        And note, while those requirements my seem unreasonable to you, they are not unreasonable for the airport sponsors .


        From AC 150/5190-6 1/4/2007 :

        Restrictions on Self-Service. An aircraft owner or operator may tie down, adjust, repair, refuel, clean, and otherwise service his/her own aircraft, provided the service is performed by the aircraft owner/operator or his/her employees with resources supplied by the aircraft owner or operator. Moreover, the service must be conducted in accordance with reasonable rules, regulations or standards established by the airport sponsor. Any unreasonable restriction imposed on the owners or operators of aircraft regarding the servicing of their own aircraft may be construed as an exclusive rights violation. In accordance with the FAA grant assurances:

  5. says

    I’m not sure why this post got hi-jacked as an E10 debate, when I was clearly imploring the FAA to clear up some confusion about an FAA approved aviation fuel, which is ethanol free auto fuel. The reality is that E10 will never be an FAA approved aviation fuel and will never be sold on airports, for a myriad of reasons, not the least of which is less energy, phase separation and the fact that it would never be approved for TC’d aircraft and in fact would be a huge liability on an airport. Since we seemingly can’t even convince airport managers to install infrastructure for an approved aviation fuel, why are we even debating a fuel that will never be approved.

  6. Greg W says

    Kent , I do not disagree at all with the apparent ease of distribution of mogas,or it’s usefulness. The A.C./SAIB would certainly help educate, I have two aircraft with mogas STC’s and have been told by others not to use mogas,(Marathon rec.90). The other issue is the STC requirement, a modification(simple as it may be) that must be done to the aircraft. This does denote that it is a different fuel than the aircraft was designed for. The 94UL avgas,(“if equal or greater”), could be used without the stc as it is a listed avgas. The “production” would be similar to E-0 mogas in that the 94UL is changed to 100LL at the refinery before leaving the pipes and could be tapped off before the tet. lead injectors,although likely transported by truck at higher cost than mogas pipelines.. In either case the person with the IO-550 will need 100LL or major modification, water injection,different engine etc., to use either fuel. You do a great job of pointing out that this is not a technical problem but rather a perception and political issue. I am a private pilot and A&P mechanic and have been in aviation since 1982.

  7. Jeff says

    An easy test for ethanol is to put a few drops of liquid food coloring in a container of fuel. If it mixes, there is ethanol, the food coloring being water soluable.

    As for what ethanol does. We in the marine industry have seen the effects since the demise of MTBE and the addition of ethanol.
    Fiberglass and epoxy fuel tanks are degraded and literally slough off material from the inside of the tanks, clogging filters and carburetors.
    The ethanol combines with outside air in the tank, separates from the fuel and takes with it other chemicals causing a soupy mess that again clogs fuel systems and obviously doesn’t run engines. This is called phase separation.
    Ethanol eats many types of natural and synthetic rubber. Carb gaskets, fuel lines, fuel bladders etc. Even “approved” fuel lines are degrading.
    The phase separation causes an acidic water type liquid to collect on aluminum tank bottoms rotting them from the inside out. Same with float bowls in carburetors.
    The addition of ethanol causes the degradation of the fuel faster. I would not trust ethanol laden fuel over 30 days old, Honda says 2 weeks.
    At least 50% of the fuel related problems we see in my shop are directly related to ethanol.
    Aircraft are like boats. They sit for extended periods, use old technology in many cases, carburetors, have vented fuel systems and don’t run well on ethanol. The difference is boats don’t fall out of the sky.

  8. drew says

    there is an unused self fueler at kmht which would be perfect for this fuel
    also kfit is considering self fuel
    if it could be sold for $4/gallon it would be a world beater.

  9. Dietrich Fecht says

    At first we all have to thank Kent Misegades and Dean Biling for the engagement to establish more mogas, a special auto fuel without any content of ethanol. Mogas could be a solution for a wide fleet of existing aircraft with 10,000s of planes which are not designed for the use of todays widespread auto fuels with ethanol content.

    It is no secret that many of individuals and companies in the aviation world see their engagement only as a business for making profit as much possible. That is very o.k. but we have to understand that when it comes to statements what might the best for small aviation or what technically makes sense. One point is the sale of fuels at airports. Privately managed FBOs very often see a benefit for them when fuel prices could be hold up as much as possible and when no other alternative would be allowed. They believe this business politics help them staying profitable in business. That might be right for a suicidal short time but in the long run it is one point how destroying small general aviation.

    Beside flying with ethanol free auto fuel (mogas) with planes which need that (or leaded aviation fuels) I believe we should have as soon as possible airplanes which can handle auto fuels with ethanol content. So that no harm has to be expected when E10 and ethanol free fuel is mixed.

    For the future we need very urgent planes which are designed and certified for fuels with ethanol content. Simply because it is a fact that the amount of nearly all combustion engine gas fuels have an ethanol content today. We like it or not.

    If the FAA clears with a statement with what fuels aircraft can be flown it should be included, that aircraft which are designed or modified to fly with auto fuels with ethanol content are legally allowed to fly with that fuel and would have the right to get it in their planes at public airports.

    • Kent Misegades says

      Dietrich, there are multiple problems accepting any level of ethanol in aviation mogas:

      1. Open fuel systems result in water absorption and damage to fuel components. Mods to the existing aircraft fleet would be very difficult and costly.

      2. Ethanol has only 70% of the energy as gasoline, not a big deal for cars but very critical for aircraft. Think of take off at gross weight on a hot, humid day at altitude when you need 100% power and nothing less.

      3. The EPA’s RFS2 ethanol mandates aim at taking the nation to E85, 85% ethanol, not E10. We might be able to make some planes tolerant of E10, but anything higher would be very tough, and with higher levels of ethanol our power is dropping, not good news.

      Besides, until there is a separate pipeline network for ethanol (don’t count on this), there will always be ethanol-free gasoline coming out of these pipelines at fuel terminals, where the ethanol is first added.

      It may be hard to get ethanol-free at gas stations, but that is not the point since the ideal situation is a network of suppliers delivering aviation-grade, ethanol-free, lead-free mogas from the terminal to the airport, just as avgas and Jet-A are today. The current avgas suppliers could do this in a heartbeat if they wanted to. Mark Ellery’s Airworthy Autogas company aims to fill that void and I wish him well on this.

      Lastly – check latest news on the growing call in Congress for a complete repeal of the ethanol mandates, for instance from Rep. Goodlatte of VA. Especially strong agricultural states like mine (NC) are really suffering due to the rising cost of feed due to ethanol mandates sucking up nearly half of the annual corn crop.

      GM will not like an end to the mandates though – a friend of mine in Nebraska says his corn farmer friends have been trading in their new pickup trucks for new Corvettes this past year, a result of the high price of corn demanded by the artifical, market-distorting market created as a result of government mandates, forcing consumers to buy a product they normally would reject. German drivers wisely gave ethanol a big thumbs down last year which caused all kinds of finger-pointing in Euro-politics. Sure wish US drivers paid more attention to what they put in the vehicle tanks.

    • Joseph Greulich says

      If your fuel contains alcohol it degrades very quickly, gives less power requiring more fuel per hour, attracts mosture , attacts everthing (rust, corrosion,gum,varnish, congeling, neopreme) , bad for aircraft and autos, any and all fuel systems. You will loose up to 10% of your power with E10 and there is not a 10% difference in cost … It is a rippoff !

  10. says

    There are two parts to the fuel issue. One is the engine and the other is the fuel systems and storage parts.

    Not an expert here but my information and concern is the inadvertent mix of Mogas from one thinking that there is little difference or got the wrong stuff accidentally. FBOs will be fine but what about that self filling concept?

    My understanding is that E-10 can be hazardous to the fuel system parts. Do you have any info on that? I assume the only way to tell what is what is by color.

    If fuel system failures are not immediate, flying rental planes could be like a ticking bomb?

    • Kent Misegades says


      One can not trust the fuel at gas stations, even when labeled as ethanol-free. Always check for its presence which is very easy to do. See Petersen Aviation’s web site for details on this.

      Otherwise self-fueling is fine. Consumers are generally smart enough to know not to put diesel fuel into a gasoline car and vice-versa. Pilots for the most part are even smarter. But mis-fueling still occurs with Jet-A and Avgas at airport. You can not fix stupid.

      While there are a few certificated LSA aircraft that permit up to E10, I know of no company that recommends it as the ideal fuel. Best in these cases remains premium (91+ AKI), ethanol-free gasoline.

      Mogas, BTW, contain 2% more energy per gallon than 100LL Avgas, a little-known fact.

      • says

        Thanks for the feedback and ref to Petersen. I will check that out. We are dealing with Tecnam aircraft which are by design able to take E-10 as long as they have the Rotax engines. MoGas has that advantage as it is the base petroleum product and refineries have to produce it first. Distribution systems are too old and too expensive to change.

        • Kent Misegades says

          Tecnam has a policy that 100% of its aircraft will operate on mogas, even their twins and their new four-seater. It is no wonder that they are the world’s largest light plane manufacturer. My son is a certified A&P and Rotax repairman. He says that while the Rotax can operate on E10 or 100LL, it is designed to operate best on 91+ AKI, ethanol-free, lead-free gasoline, aka mogas.

          • Mark says


            I just noticed that last comment of yours, and wanted to clarify something. The MOGAS appropriate for a particular engine will be contained within the STC. For instance, Peterson, who was mentioned above, states that 87 octane is absolutely fine for many older engines (presuming, of course, that it’s Ethanol free). This is an important distinction, as in many areas 87 is available but higher octanes are not. As long as that particular engine is STCd for the lower octane then it’s not just 91 that counts as MOGAS.

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