Unleaded Avgas Controversy Steps Up Its Pace At Sun ‘n Fun


As frustration builds over certifying a replacement for leaded avgas, the leaders of three GA advocacy groups met in a Town Hall setting this morning (April 6) at the Sun ‘n Fun Aerospace Expo. Emceed by Sun ‘n Fun President/Chairman “Lites” Leenhouts, AOPA President Mark Baker, EAA Chairman Jack Pelton, and General Aviation Manufacturers Association President and CEO Pete Bunce defended the Eliminate Aviation Gas Lead Emissions (EAGLE) program.

Later that day, George Braly, president of General Aviation Modifications Inc. (GAMI), held a press conference at his display booth rebutting much of what he heard at the Town Hall.

In the morning session, Bunce started the presentation, listing some of the participants in the EAGLE program, including the FAA, EPA, Department of Transportation and the National Science Institute. Later in the discussion, he added the National Petroleum Institute to the list, among others. “We have a timeline and we have a compromise [between] what’s doable and what can save the industry. Our future depends on finding a solution.”

Pelton took the next turn at the microphone, saying, “This is an international problem. There is no fight here [to preserve leaded fuel]. The EPA is going forward with an Endangerment Finding, and the deadline to get the lead out is 2030.” Pelton also pointed out that the problem has multiple intricacies, and stakeholders. “The fuel, itself, is only one. There’s also distribution, storage, and the fuel refiners and blenders that will make it.” The panel noted that to support multiple options for unleaded fuels, FBOs would be challenged to add dedicated tanks for each grade.

Baker enumerated more of the challenges, noting that the annual consumption of avgas nationwide totals just 180 million gallons, “about 3–4 hours’ worth of auto fuel.” He also pointed out that the sole producer of the lead anti-knock compound used in aviation fuel, Liverpool, U.K.-based Octel, is vulnerable to not only the U.S. EPA, but also growing restrictions on lead in Europe. Baker made the case, further, that counting on multiple octane grades of fuel is impractical and dangerous, as misfueling a high-compression engine with low-octane fuel could cause an engine failure. “The 30 percent [of the general aviation fleet] that requires higher octane burns 60 to 70 percent of the aviation fuel,” he said.

Asked about criticism of the results of the Piston Aviation Fuels Initiative (PAFI), Bunce defended the program, saying, “Fuels need to be tested for transparency to get fleetwide authorization.” He argued that PAFI was not meant to develop lead-free fuel, but rather to develop a testing program for candidates for a drop-in replacement for 100 Low Lead (100LL).

The 2013 PAFI mission statement reads:

-Facilitate the development and deployment of an unleaded AVGAS with the least impact on the existing piston-engine aircraft fleet. This is a govt/industry collaboration to ensure all stakeholders are involved in a coordinated approach to fleetwide implementation.

-Established to develop a path forward for the identification, evaluation and fleetwide certification and deployment of the most promising unleaded replacement fuels.

-Overcome the significant hurdles which have hindered past efforts to develop an unleaded avgas replacement.

-Provides a sound process to ensure that this goal is achieved with a minimum of disruption to the general aviation industry and with the greatest likelihood of marketplace success.

Baker followed up with a discussion of the differences between a candidate fuel following the Supplemental Type Certificate (STC) pathway vs. industry-consensus testing such as through the ASTM validation process. “An industry consensus is needed for testing,” he said.

Bunce said, “An STC is proprietary. We [manufacturers represented by GAMA] have no transparency. All the chemicals [in the fuel] must be vetted, not only by the FAA, but also by Europe [to ensure against] issues 10 years down the road. We need industry consensus standards.” He cited the recent development of sustainable aviation fuels (SAFs) as an example of such a consensus.

Addressing the question of the cost of unleaded aviation fuel, Baker didn’t dispute that the new fuel would be more expensive, but that might be temporary. “Long-term,” he said, “any fuel without the [infrastructure] restrictions of lead could become less expensive.”

Bunce suggested that existing tests for detonation could be “antiquated.” “What if the margins were too big on the previous test standards?” he asked.

In his summing up, Pelton said, “We need the fuel, the certification process, producers and a distribution system. We have to get all those to line up or someone will be left behind.”

At his press conference later that day, GAMI’s Braly didn’t mince his words of frustration, citing last summer’s Supplemental Type Certificate. While it included just a small number of engines, there was the implication that the list would expand “to include all spark-ignition engines and the aircraft that used them,” Braly said. “That sounded like fleetwide approval to us.”

Braly went on to show a copy of an email he received from the FAA on March 2, complete with an 18-page list of engines and a 51-page list of “hundreds of aircraft models” that would be included in the STC. That email followed an extensive audit by the Atlanta field office of the FAA from Dec. 17 to Jan. 4 examining the last 12 years of research and testing, he said. The message he received from the audit team was that the STC was “suitable for FAA approval.”

Now, Braly said, another audit is ongoing, scheduled for completion by May 2, and he’s been assured FAA officials are “almost certain” the STC will be approved at that time. He is not convinced.

Braly went on to describe a litany of hoops he says GAMI has been asked to jump through, including six Technical Advisory Board hearings starting in 2010, consisting of “rooms full of FAA subject matter experts.” He also described his certificate of production authority that shows GAMI has not only the right but the obligation to rescind production approval to any refiner or blender that fails to maintain GAMI’s standards—and a process through which the refiner would be obliged to supply a 5-milliliter sample of its license-produced product for quality-control analysis.

At the close of the press conference, Braly related a family phone call, during which his son said, “Dad, you’re the single most stubborn human being, ever.” Braly concluded, “It’s important that we get this done for general aviation.”

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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. The arrogance of government employees is a breathtaking existential threat to every one of us. It exists at every opportunity, and is relentless in its passion to extinguish the natural human spirit. This AvGas BS is but one tawdry example. Sadly, they have no shame.

    • Yars … watch these two Social Flight recorded webinars with George Braly. The guy did yeoman duty solving the problem and is being blown off by Air-1:

      Dec 8, 2021:
      Feb 9, 2022:

  2. I’m a little confused. GAMI’s Braly was interviewed recently by Max Trescott (Aviation NewsTalk Podcast) and sounded very positive. Much of what’s in this article attributed to Braly was discussed in detail in that interview. Are EAGLE and GAMI not on the same team?

  3. Who does Braly plan to make his fuel and get it to the customers? I only ask because there’s some oil company conspiracy crap going on in the background, and just FYI, Braly will be having his fuel made by oil companies. How do I know if I do not know? Who else will refine it, mix it, and distribute it?

    So now we have an interesting parallel to Covid. Doesn’t this PAFI vs STC thing sound a lot like when some medical alphabet decided they, and only they, would develop approved tests? I can guarantee you that there are people in the FAA who have power and influence that do not like Mr. Braly if for no other reason than his appearance. They don’t like GAMI already over lean of peak and shock cooling. Some people just cannot stand it when the things they know are challenged by the wrong people, and they weirdly then hate those who unveil truth.

    (I suspect in the original version of the Emperor’s New Clothes, the kid and his family suffered some gruesome fate, and not from the emperor, but from some patriots who were sure that the kid was a threat to the empire.)

    Is that all the narrative here? Braly didn’t knuckle under for the PAFI program so his solution shall not be deemed holy by the high priests of the sky?

  4. If the goal is to, “Facilitate the development and deployment of an unleaded AVGAS with the least impact on the existing piston-engine aircraft fleet” Why don’t AOPA and EAA seem to support George Braly and his 100UL fuel? Braly has a fuel that is very promising and yet he is being treated like a pariah by the industry that he is trying to support. I am very concerned that both AOPA and EAA seem to have placed so much support first behind PAFI and when that failed after ten long years, now EAGLE. Braly seems to have a very strong candidate fuel. Why would these organizations choose to support another beurocratic organization to develop a fuel by 2030 when they could instead support what Braly has already achieved?

  5. Relying on the private sector was a bad idea from the start. What we are seeing now is the reason – a For Profit stakeholder pressuring a public agency to approve their proprietary product as the only approved replacement fuel. That is never going to result in the most affordable or reliable source. The only way we are likely going to accomplish this is to create a publicly funded, (government) program to develop the fuel.

    • Ron, I think you are on to something. Follow the money…
      If George Braly and the staff at General Aviation Modifications Inc. (GAMI) would sell their fuel patents and such to the highest bidder (Exxon, Shell, BP or whatever “Major Oil”) we would be pumping 100UL around the world by morning.
      I still believe the hold-up is the taxes. How is the FAA and the many other bureaucracies get their cut??? That’s why they created PAFI and now EAGLE to figure that out. The “Major Oil” companies have that pay-out network established and in place. They’re ready to grease the skids.

  6. I was at sun n fun maybe 10 years ago at a meeting on unleaded avgas. They made it sound like the problem will be over in about a year. What a joke. It seems like a waste of time I would never repeat but I see a lot of people are. At this point I would favor 94 UL and modify the airplanes to use it. That is what happened to the 115/145 loss of fuel. all the users of that fuel modify their engine and got a STC. A lot of Aircraft that got the STC‘s where fire bombers ex military aircraft. Most of the mods that are needed for today’s aircraft would involve larger intercoolers and ignition timing changes.

    • That may have worked with transport and restricted category planes, but will not work with normal category planes whose single engine performance is already marginal at best. Detuning engines to run on reduced octane levels would eliminate that single engine performance or reduce the gross weight of those planes to make them unusable.

  7. Over two decades ago there were two paths to follow: modify our existing engines with new tech to run on car gas or do the chemistry problem and reformulate the gas. After all this time we did neither and the reasons are so, so simple. Money!
    There is no reason why our equivalent to lawn mower engines couldn’t really run without lead. Change the spark method individually in each cylinder using the same tech as what is in each car we all drive each day and alter the fuel regulation at the intake tube (not fuel injection) individually. The other was to solve a chemistry problem. Neither were insurmountable, but both take money to solve but neither would happen because both things topple the sacred cows of the engine/airframe, fuel industry, the FAA, and yes the power of the alphabet groups like aopa.
    The aviation engine/ air framers/ avionics/ and component manufacturers are really economic cartels who set prices, set what you can buy, control who gets it, and while they blame the FAA set barriers to entry of new ideas, products, and outside manufacturers. Seen a new engine lately? Seen the trail of new engine rubble over the last 30 years? None of them worked? Really? Meanwhile we soldier on with “old reliables” in Lycoming and continental THAT DESTROY THEMSELVES AS THEY ARE USED WITH 100LL. Yup, lead slowly kills not just the valves but contaminates THE ENTIRE rest of the engine from bearings to accessories that it touches. So it’s a great business model where the user willingly ruins what he buys and is forced by the regulation back to the guys who sold it to him. What a country!
    As for fuel, poeple can criticise Brailey as much as they like but HE IS RIGHT. He did experimental chemistry on a tiny small scale, played by the rules, and has documented provable results and is criticized for it and stood up by the FAA as a kind of nut. The idea that master chemical companies (the oil industry) couldn’t do chemistry or production flies in the face of reality. They KNEW lead from car gas lowered the IQ of everyone who lived by a freeway by 4 to 6 points back in the 70’s which was the reason we got rid of it. They went along with the EPA because their lawyers knew the intire industry would lose on courts everywhere. But with a lead exemption for avgas only enabled foot dragging so as long as the users keep buying why change? But you know what? Seriously, stop making 100ll and you will see all kinds of ideas and people jump up. It may take just that to get anywhere.
    Now for the FAA. They have all along claimed that it’s the industry not coming up with new tech and products like engines and fuels while the industry says the FAA prevents them from making new stuff and a barrier to entry. The lawyers know this is half true. The industries have certificates and the last thing they want is to make something really new that kills thier existing products and allows new producers (ask Rotax about this) or Brailey’s GAMI to entry. So it’s circular logic that the FAA winks and nods to. They have their agenda too.
    As for the aviation lobbying groups, I love Jack Pelton. He’s an honest man. He knows how messed up this is and I don’t blame him. AOPA is simply has forgotten about me and all of the other owners out there for the last 25 years. Mark Baker has done a lot of good but I feel he has not represented my best interests in all of this for a long time and deep down he knows the gravy train is over all somehow because of one county with two airports stopped selling 100ll exposed this whole sordid mess for what it really is.
    But, what nobody saw coming was the electric aviation industry and that is almost here that grew up in the last five years that the entire aviation cartel wants to stop in any way possible. They won’t: Apple bought all of Joby last Thursday while we all fight for the scraps of the past.

    • What you fail to recognize is the small scale of GA compared to the large investments that must be made to make these “simple” changes. Unlike the avionics people who are raking us over the coals I doubt Continental an Lycoming are awash in cash and Avfuel is such a small part of the refining equation the oil companies really don’t want to bother. AOPA decided to cater to the Cirrus crowd years ago. Though the do some good in Washington they live an a fantasy world where a $100,000 C-152 is a bargain and putting $80,000 worth of avionics in a $35,000 airplane makes sense.

      • I believe your statement on the oil companies may very well be true. With the avgas market being very small verses the liability involved, I would not be surprised that this new EAGLE initiative fails also. The oil companies are not going to lose much revenue if lead is banned and the sale of 100LL stops.

  8. I thought AOPA and EAA were supposed to be on our side. Here they are going along with the FAA’s latest plan to study unleaded fuel to death They should be pushing the FAA for blanket approval of GAMI’s fuel. Not that it would help much. Look how long they pushed for BasicMed. It was obvious that the FAA had no interest in it and we wouldn’t have it now without congressional action.

  9. The part about this saga that I missed:
    Where/when/how armed troops are going to compel ANYONE to buy even one ounce of STC-approved AvGas substitute.

    Issue the STC, per Rule. Let the marketplace decide.

    • Yes this is a great embarrassment for the entire Aviation community. Probably the worst public relations disaster for Aviation I’ve ever seen.

  10. Since I’ve been aviating, I have watched 100/130 come and go. 80 come and go, 100LL still here, 94UL come. I’ve burned them all in that O470R. Leaded fuel was a power design consideration in pre-WW2 aircraft engines and in the 1925 Model T. When leaded fuel production was stopped briefly (for health issues) in 1922-24, Henry reduced the compression in the Model T engine to burn unleaded gasoline.

    GAMI says they’ve solved the problem. I believe them. I’d be happy to burn it in the airplane with the Peterson STC or the EAA STC. The general quality of motor fuels today is probably as high as they have ever been, with the exception of alcohol contaminated fuels which not only corrodes fuel systems but destroys 2-stroke snowmobile engines and the Pb fouling problems. And the regulatory problem: I cannot use the Mogas STC in Part 135 ops.

    Swift says they solved the problem too. I’ve used their fuel. It works. I don’t like tankering fuel to the airplane. I’d rather buy it from the FBO, but the present squabble will keep me tankering until the boys grow up and provide a solution that has been available since 1972 in engines nearly as primitive as those monsters we hang on production aircraft.

    I’d be pleased if the PAFI/EAGLE/wutcomesnext groups came out with a dozen different fuels and I’m pleased that Craig Sincock is working with GAMI and hopefully others to get cheaper fuel to market. We can do it. We have done it and made engines for a century that’ll burn anything that has heat.

    Come to think of it, my grandfather had a Ford Model A he let me drive around the farm. It’s startup, cruise and shutdown were more complex than the aircraft’s. And it would run just about any fuel that would burn in 1929.

    Here’s the starting and operating procedure:
    1. Brakes Set
    2. Spark Control Lever — Full Retard (UP)
    3. Throttle — half way down
    4. Fuel Valve — On
    5. Choke Control Valve — Full clockwise and back 1/4 turn (temp > 32)
    back full turn (temp < 25)
    6. Ignition Switch — On (we call it Contact)
    7. Clutch Pedal In
    8. Choke Control Out
    9. Crank Engine 3 revolutions and push Choke In
    10. On engine start, push Throttle control UP
    11. Put Left (Spark Control) Lever all the way down or 3/4 depending on engine timing.
    12. Allow engine to warm up and turn Choke control valve clockwise for smooth operation.

    Cruise Operation
    1. Move Spark Control Lever up prior to engaging clutch (Retard)
    2. Advance Spark when driving (lever down until ping is heard, then back off).

    1. Engage Brake
    2. Spark Control Full UP (Retard)
    3. Throttle Full UP (Idle)
    4. Fuel Valve — Off until engine stops
    5. Lights & Accessories off
    6. Ignition OFF.

    Our engines are simpler to start than that, most of the time.