GAMA Hosts Pre-Brief On Life After EPA’s Ruling On Leaded Aviation Fuel


In anticipation of an imminently expected endangerment finding from the Environmental Protection Agency (EPA) on leaded aviation gasoline, the General Aviation Manufacturers Association (GAMA) hosted an industry-centric “background” briefing for aviation press this morning. GAMA was clear from the beginning that this was an industry-only briefing and did not come under the “umbrella” of the Eliminate Aviation Gas Lead Emissions (EAGLE) initiative, described by GAMA as “a comprehensive public-private partnership consisting of aviation and petroleum industry and U.S. government stakeholders.”

Representatives from GAMA, the Aircraft Owners and Pilots Association (AOPA), Experimental Aircraft Association (EAA) and the National Air Transportation Association (NATA) participated in the discussion.

The panelists cited progress toward fielding a replacement for 100 low lead (100LL) high-octane gasoline that would be suitable for fleetwide use. While an estimated 70 percent of the current piston-aircraft fleet can safely use available lower-octane lead-free fuels, the remaining 30 percent that require higher-octane fuel to operate safely fly an estimated 70 percent of the hours flown by the entire GA fleet.

The panelists noted that the expected EPA endangerment finding, in itself, does not constitute a ban on continued use of 100LL fuel. In fact, the group stressed the priority of retaining the right to distribute and use 100LL until an acceptable replacement is in place.

However, the panelists did acknowledge that the EPA endangerment ruling does set a “pathway” to future rulemaking related to lead emissions in aviation fuels.

There was extended discussion on the difference between the supplemental type certificate (STC) route to acceptance of a replacement unleaded fuel and the so-called ASTM (American Society for Testing and Materials) route, involving a “collaborative government FAA program to test candidate fuels, generate report and data, and distribute to fuel providers,” enabling the FAA to gain “industry consensus” and issue a fleetwide approval.

The panelists were careful to assure that the FAA, as the arbiter of safe aviation operations, is the final authority on approving a replacement for 100LL, not the EPA. That said, the discussion revealed that—for the first time—regulatory standards for lead emissions in aviation fuel will be established as a result of the expected EPA endangerment finding. GAMA assured the participating journalists that there would be further briefings once the EPA endangerment finding is finalized.

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Mark Phelps is a senior editor at AVweb. He is an instrument rated private pilot and former owner of a Grumman American AA1B and a V-tail Bonanza.

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  1. We need to get the racing community, the antique auto community, the boating/Marina industry, and the aviation community to get behind an E-free unleaded solution like UL94 avgas, that can be produced in massive quantities at reasonable cost. Thanks go to Swift Fuels for getting this supply chain started. Regarding the 70% figure mentioned above, yes, the Cirrus fleet cannot presently use UL94, but if you look a little deeper, Cirrus aircraft should, by now, be burning Jet-A. Both Cirrus and Continental are both owned by AVIC, and the Continental website has been making this claim for YEARS:
    “Continental Aerospace Technologies™ Jet-A engines are world-class benchmarks in General Aviation, with more than 7,500 are produced and shipped and more than 2,000 engines in operation today, reporting upwards of 10 million flight hours. They are favored by flight schools and specified by major OEMs including Tecnam®, Cessna®, Diamond® , Mooney® , Glasair® , Piper® , and Robin® . These Jet-A fueled engines operate on universally-available aviation fuel kerosene (Jet Fuel, Jet-A and other certified aviation Jet fuels).”
    Do you see Cirrus in this list?? WTHeck? Are we making 100LL so universally available, that AVIC lacks motivation to put their OWN lead-free engines in their airplanes?

    • Have you not heard of GAMI G100LL?
      It is certified for just about all piston engines in the GA fleet.
      It’s all a matter of production and distribution now.

      • I have said this before but it bears repeating: The G100L model is not a reasonable approach. My engine was certified for 80 and I used it until it disappeared in the mid ’90s. I briefly switched to 100LL but had substantial problems with Pb fouling despite ultra-aggressive leaning. I bought the Petersen STC for mogas, ran a steady diet of Mogas (80/87) except for the occasional tank on the road where mogas was not available.

        Why is the GAMI STC problematic? Not their fuel. It will work. The process of use though is. My STC or the EAA’s STC will allow me to burn any brand and any suitable ETOH free mogas in my airplane. A one time cost was paid because the FAA said so, and required zero modifications to the airframe or engine, other than a couple of placards.

        GAMI’s process is everyone who wants to use it must have their STC. If G100UL is the only fuel at an airport, then that airport effectively has no fuel for any aircraft that does not have GAMI’s STC. This will require a major change in fuel information charting. Already, it is impossible to see what the price of the GAMI STC will be on their web site, unless you provide them with an application to buy it. Why, pray tell, is that?

        It will also stifle competition for others who decide to follow the non-ASTM or other standards route. Or alternatively, Swift or other entrants, including the major fuel suppliers will bring their own XX100UL product to market, requiring their own STCs, for example an EXXON-Mobil STC and a Phillips66 STC and a Shell STC etc…

        This will be a regulatory and logistical nightmare for GA operators who do not operate on a fixed schedule and for FBOs who must track and enforce this information. We cannot get FBOs to carry JetA, 100LL and an unleaded fuel now let alone carry 4 brands of xx100UL. It will also make it very difficult for FBOs to change fuel suppliers, further decreasing competition and fostering monopolistic pricing.

        I am not a fan of ASTM, a private organization. NIST should be the place where the standards come from where they are accessible to all. Meet that standard, your fuel is good to go in all certificated aircraft that use that standard. This approach opens the field to competition, reduces logistical complexity, improves airfield access and increases GA options so necessary for safe operations.

        • And now the airport only pumps 100LL, that you cannot use due to lead fouling. With G100UL, you COULD use it without lead fouling issues. So it looks like a win.

          • Let’s not forget that there is a ton of money to be still earned by the developers and patent owners of any unleaded fuels delivered along with , probably a hefty STC purchase fee too. None of the ” George’s ” are going to give that $ up.
            I have ” heard ” of a $ 300 to $ 600 STC fees for initial purchase … but not certain.
            I haven’t ” applied ” with my credit card information..
            And don’t intend to.
            I do recall my Peterson STC for mogas costing me around $ 95. With a decal.

        • So no technical or performance issues. Only bureaucratic issues. I wonder how much $$ it would take to buy out George’s intellectual property rights and put it in the public domain. The FAA could then approve it for “all spark ignition engines in the fleet” *without* an stc, just as they have with an stc.

      • Not “certified for *just about* all piston engines in the GA fleet”, it’s “certified for ALL piston engines in the GA fleet”. (Spark ignition engines anyway.)

        • Yes, you gotta really wonder what the heck is going on. If the EPA says 100LL is dangerous, then how much is it costing the country? Surely, if it’s worth banning, it’s worth buying out the only proven solution. The FAA has de facto agreed 100UL is a safe solution, and is trying to take it back due to politics and bureaucratic careerism.

          94 Octane will be just one more cut rushing certified piston aviation to the grave. I know all the low performance owners think it will raise their values and solve their problems, but it will be a short lived solution leading to less and less piston GA airports and the US aviation landscape starts to look like Europe.

  2. Yes. 94 octane will not work. 100 will. Now it’s just a matter of time and money. No airport wants multiple fuel tanks. One for gasoline and one for diesel. Keep it simple is the term I heard years ago.

    • Many smaller public airports already have two tanks. One for gasoline and the other for Jet fuel. There are many turbine-engine aircraft flying today into smaller airports. They need fuel also.

      Unfortunately, the KISS method often does not work with real-world situations, especially those situations where people are involved.

      • I’m pretty sure he meant Jet A, not diesel.

        Yes, Jet A is replacing a lot of 100LL use due to the rules changes in the 2000’s.

  3. It is hard to believe this issue has dragged on for so long. The indecision and lack of real progress in a solution will have a bad effect on general aviation for decades to come.

    Whether lead in aviation fuel is a real threat or not is no longer the real issue, it is a perceived threat by many in the general public along with various state and federal governments and agencies, so therefore must be dealt with.

    Everyone involved in general aviation shares the blame for this issue. All the aviation groups, federal agencies, aircraft builders, designers, and owner/pilots should have decided to address the issue years ago. It is clear, and always was in my opinion, that not everyone would be satisfied with the final solution, whatever that is. All the efforts to appease everyone does nothing but delay action and kick the problem further down the road.

    Aircraft manufacturers had an opportunity years ago to develop new engines or modify existing engines and stop installing those requiring leaded fuel in new aircraft. They should have just set deadlines for producing and installing engines requiring leaded fuel and stick by those mandates. The auto companies did it and have been successful. New aircraft fleets could be flying today using auto fuel or derivatives and much of the problem would now be behind us. Other viable solutions such as diesel/JP4 fueled engines should also be flying today in much greater numbers. These engines have been developed, and tested and are yielding great results in training fleets.

    Older legacy aircraft, antique or otherwise qualified aircraft could be exempted for some specified time for continued use of 100LL. If operators wanted to fly these aircraft beyond that time then another solution would be needed for this group. Some of these solutions could include new engines that do not require leaded fuel or auto fuel STCs I would think auto fuel or a new engine would be the best long-term solution. Perhaps there could be some type of industry assistance or rebate for engine conversions at TBO for these older aircraft. The assistance of some type for these legacy owner/pilots for auto fuel STCs or engine conversions would be far cheaper for the industry as a whole than what is being expended now and in the future for non-progress on a drop-in solution for everyone.

    Had these changes been implemented 15-20 years ago, much of the fleet today would be flying with fuels with no concerns about lead. As time moved on the older legacy fleet would be growing smaller as aircraft were retired or converted and the lead problem would be diminishing.

    • GJ, your statement “ Whether lead in aviation fuel is a real threat or not is no longer the real issue, it is a perceived threat by many in the general public along with various state and federal governments and agencies…” is both troublesome and alarming to me. While I agree with you, and agree with your statement, it makes me even more aware of the pulse of today’s general public. Forget the real science, let’s act on our perception of the danger or the “science” that comes from the highest bidder. So true, so sad.

    • Nope. The Feds have overwhelmingly the lion’s share of blame. Note the cost of certification going up had an effect on the innovation of new engine tech and airframes going down. IMO, allowing engine manufacturers who sell auto engines to aviation modification firms a release from joint and several liability claims might have helped 40 years ago, but we are where we are now.

      The regulatory and tort situation makes the certified piston GA situation untenable, and I’m not sure how to fix it which doesn’t matter because no one with influence cares. AOPA sold us all out decades ago.

  4. Here in the Midwest (southern Minnesota) the repercussions of the 100 octane panic have already started. We operate an FBO–and a month ago, the only refiner that produces 100LL quit making it–they simply found it was not worth the effort to comply with the proposed restrictions. Most of the avgas for Minnesota, Iowa, the Dakotas, and northern Wisconsin came from that refinery.

    We asked our wholesale supplier where our next loads would come from–“Kansas City (400 miles), Tyler, (Texas 952 miles!), Chicago (378 miles, but not served by several truck lines due to delays at the loading terminal) or Michigan 600 miles around Lake Michigan.”

    You can’t pipeline 100 octane (fear of “interface fuel”). We are working with other FBOs to come up with a plan to use rail cars–a small rail tanker holds about 4 truckloads of product–a large one 6. The unknown is whether the rail cars would have to be “dedicated exclusively” to 100LL so there is no chance of intermixing with other fuels. It is relatively simple to find FBOs that will take “split truckloads” of fuel.

    At our FBO, we have sold 94 octane no-alcohol fuel ever since it has been approved–so the low-powered fleet is covered–as the article mentions, “the 30% of 100 octane burners that CAN’T burn lower octane burn 70% of of the hours”–what the article misses is that those 30% that can’t use lower octane fuel burn far more gallons per hour–making their fuel consumption percentage even HIGHER.

    As an aircraft dealer, I won’t touch an airplane with a 100-octane only engine any more.

    IF the FAA was thinking ahead, they would take a leadership role and ASSERT THEIR AUTHORITY over regulation on the fuel–providing a several-year “phase-in time” for continued 100LL use. Samuel Johnson, in 1791 said “The road to Hell is paved with Good Intentions.”

    • I agree, but good luck on the FAA actually exercising their authority. TSA has walked all over the FAA since 9/11 and when Huerta was administrator he gave away Santa Monica airport without much of a fight. The current administration in office couldn’t care less about general aviation with all the environmental zealots running things.

    • Much of the reason for the situation is that within the FAA there are no positive, and many negative incentives to say yes to any change for piston GA. Congressional oversight was supposed to be the check and balance. Congress has not functioned close to properly since pre 9/11.

  5. I am ready to pay extra for G100UL – I only need it to be available – partial solutions will not work, of course, but this one is a no brainer. Please make it available.

  6. There is zero excuse for this dragged out process!
    Lead is not good for engines or people;
    Unleaded 100 Octane has been available for decades in Scandinavia, and is available now in North America.
    FAA must give a blanket approval for unleaded 100 Octane fuel; not STC’s, not other paperwork nonsense.
    My O360 engine would be much happier on Mogas, but there is no STC for my airframe, because with small numbers, it wasn’t worth doing the tests; the STC process is ridiculous.
    How can businesses continue in such a regulatory quagmire?
    The solution is clear; get it done now; blanket approval of unleaded 100 Octane; expedited phaseout of of 100″LL”
    (and; keep no nothing deadlocked Congressional “Representatives” out of what they simply cannot understand)

    • Unfortunately, you need Congress. To fix it, partisans need to go to their primaries with a default choice of voting for challengers, and no voting their own losers in elections. Independents need to not vote for incumbents until government starts working again.
      Only vote for candidates that seem acceptable. Voting any given line is optional. Stop holding your nose and voting for the lesser evil.

  7. we must remember that there is a reason that none of the continental diesel engines with a Hp of over 180 hp or so are being sold. they cannot deliver the 300 to 400 Hp required for our existing 4 to 6 passenger aircraft.

    the aircraft industry desperately needs a 300 to 400 h p engine that runs on Jet A or locally available common gasoline that is used in cars or boats.

    • I think the reason you don’t see bigger piston engines is because of the Micro-Turbine development. Many different large manufacturers are spending big on the Multi-Fuel Turbine-Hybrid design. Especially once the MOSIAC rules go into effect all the 6 place and larger aircraft will be turbine.

      If you own a 100 octane aircraft you better be rethinking your future engine options.

  8. Folks- There is going to be a universal 100 octane Unleaded Avgas available before 2030.. And the boaters and racers will “be” onboard since the single supplier of tetraethyl lead in the world will discontinue manufacture as soon as unleaded Avgas is widely available. And 100LL will disappear a lot more quickly than people imagine once unleaded 100 octane goes into production. And it won’t be a “Secret formula” with a proprietary STC business model. To satisfy the trial lawyers and refiners, it will have to be a certified and tested publicly visible formula (even if proprietary..) before the handful of future refiners will agree to produce and distribute it.