Swift Fuels Raps Environmentalists’ ‘Ultimatum’ On Unleaded Fuel


Swift Fuels CEO Chris D’Acosta says a legal threat against California FBOs to sell a new-to-the-market unleaded 100-octane fuel is based on the premise that G100UL, developed by General Aviation Modifications Inc., will soon be commercially available, something he says is unlikely to happen anytime soon. In public comments and in emails to AVweb, D’Acosta claims that the lack of ASTM approval of the fuel means that it is not yet commercially viable because it likely will not be accepted by the aviation industry, insurance companies, distribution companies and fuel sellers without proper ASTM vetting. “The FAA does not certify or approve fuel in the marketplace. Industry does,” D’Acosta told AVweb in an email. “It starts with ASTM specifications which is then tied to the fuel supply chain, safety regulators, insurance provisions, etc.” Swift Fuels is already selling a 94-octane unleaded fuel that D’Acosta says has both FAA STC approval and the ASTM fuel standard and significant product liability insurance coverage for aviation. It is developing a 100-octane unleaded fuel and intends to have it similarly certified.

As we reported earlier, the lawyer for California’s Center for Environmental Health (CEH) sent a letter last December to FBOs throughout the state telling them they must commit to switch from selling 100LL to G100UL by March 1, 2024, hoping it would then become available in large quantities. Vitol Aviation, which is now licensed to produce the fuel, is ramping up production, but it won’t be ready in time for the deadline set by the lawyer. The fuel has been approved by the FAA for use in piston engines used by specified aircraft in the U.S. through an STC process. GAMI founder George Braly told AVweb the FAA approval for all aspects of the fuel’s production, distribution and use in aircraft satisfies the “commercially available” definition that triggers the requirement for fuel sellers to switch to his fuel. In a public comment below the earlier story on the lawyer letter, D’Acosta disagreed, saying G100UL “has not completed the necessary prerequisites with [industry/ASTM] to be commercially available in the marketplace.” He also criticized the legal threat. “Accordingly, I believe the lawyers of CEH have no right to impose this unjustified ultimatum on California FBOs.”

Russ Niles
Russ Niles is Editor-in-Chief of AVweb. He has been a pilot for 30 years and joined AVweb 22 years ago. He and his wife Marni live in southern British Columbia where they also operate a small winery.


  1. This fiasco has gone on way too long. It’s time to get over it and get on with it. In this case the ends justify the means.

    • Swift Fuels are a bunch of cry babies. They got beat to the finish line and now they want a participation trophy.

      • Actually, they didn’t get beat to the finish line. They have been selling for years. Their dilemma now, is that they will have to stop gouging and start competing. America was built on free market competition. The current administration doesn’t like that idea. There is no reason these alternative fuels shouldn’t be competitive with prices at the car pumps. Swift didn’t care about opening new markets. They only needed the few they have now at crazy inflated prices. Kinda sucks when you won’t have the monopoly on unleaded fuel anymore.

        • “There is no reason these alternative fuels shouldn’t be competitive with prices at the car pumps.”

          There are at least two:
          1 – Massively larger market; and
          2 – Gas stations can operate on razor thin margins if they can get you into the mini-mart, where the profit lies.

    • Seconded. The sooner I can fill my tank with unleaded on the field the better. I’m tired of filling 5 gallon cans at the gas station then pumping it on the ramp to avoid cleaning out lead deposits from my Rotax oil tank every annual.

  2. I guess I am confused about all this STC talk. Do we need STCs for different engine oils? Does current 100LL have an STC? Did the old 80 octane have an STC? Folks just bought the octane version they needed. Seems like the need for an STC nullifies the concept of “direct” or “drop in” replacement. So one STC for each and every airframe? Paperwork? Legal costs? Tracking? It really is a travesty what the FAA put GAMI through. Bunch of weak ineffectual scared bunny bureaucrats. A sign of the times.

  3. So we are hiding behind an antiquated ASTM to justify lack of progress and innovation in serving the entire GA community with a viable alternative fuel. Nice.

  4. What does an ASTM standard offer here? When I read the data on the ASTM.org website it seems to me that such a standard would be specific to the product to ensure that the product being produced over time conforms to its original specifications.

    I believe it verifies that the G100UL being made by various producers today is the same and repeatable and that 10 years from now, the product is still being made to the same standards.

    So is ASTM and the rest of the industry saying that production of a consistent G100UL is not possible without their certification? Does ASTM have some type of enforcement authority if a producer fails to meet standards for a certified product by their organization?

  5. No. What we operators are saying is this: Fuel for our aircraft is a fungible commodity. As long as the fuel can be safely used (ie drop in replacement), there should be no need and no requirement to purchase an STC for every fuel approved for the aircraft (airframe/engine) combination. The ASTM standard demonstrates that the product itself meets the standard and holds the manufacturers accountable for meeting that standard. It will also provide a basis for recovery if they don’t.

    • But many Lycoming engines are rated to operate on No-Lead MoGas. So how could they deny coverage – especially for those of us who own/fly an EExperimntal class plane?

  6. Unleaded 94 Motor octane fuel (UL94) is essentially 100LL without the lead.
    Proof positive that we already had a drop in replacement for small GA piston planes.
    The powers that be do not want simple solutions nor lower costs for 2 and 4 place GA piston planes that average families can afford.

    • The statistic that gets bandied about is that while the majority of aircraft in the small GA fleet can burn 94UL, the aircraft that burn the *majority of fuel* cannot. Bonanzas, for example. Cirruses. Anything with a higher-compression engine. My airport offers 94UL, and the flight schools use it in their compatible planes, as do some of the owners of compatible planes. But that still leaves lots of planes that need a 100 octane replacement.

      The good news is that the airport plans to bring G100UL onto the field as soon as GAMI and Vitol can deliver it.

      • I could believe it’s true that the aircraft that “can’t” burn 94 octane burn the majority of the fuel. It’s quite plausible, and is often repeated – but is it actually true? How do we know? More and more, the hard-working high-power machines with 6+ seats burn jet A in a turbine. All flight school aircraft and almost all 2-seat aircraft could burn 94 octane. Most 4-seat personal aircraft could too: pretty much all c172s and PA28s (with an STC) and apparently every Cirrus delivered in the last 13 years. I suspect that, if you split out all the aircraft that could use 94 octane if they had any required STC, you’d find that a majority of the fuel is actually being burned by aircraft that could operate on 94 octane unleaded. But I could be wrong: shown actual data I’m willing to change my mind 🙂

  7. The reason G100UL doesn’t have an ASTM is because the formulation is proprietary, meaning if GAMI gives away the formula, they won’t get the compensation they deserve for the research, development to solve this problem.

    Crack that nut, and it’s off to the races.

      • Patents are explicitly intended to allow the inventor to disclose the invention without “giving it away.” It can’t be about the patented inventions. And a good chemist could reverse engineer the fuel. That’s not the issue here.

  8. Disappointing but not surprising that Swift is spreading FUD to try to delay rollout of G100UL. Reflects very badly on the company, in my opinion, and would make me choose a fuel other than Swift whenever possible.

  9. Please, please, can we have UL94?

    No mystery additives. No STCs. No ethanol. No lead all over the inside of the engine. Just store it on the truck: no new tankage required. And most of us can burn it tomorrow morning. Sure, the bigger volume will be 100LL from the big tanks; fine. Let the big tanks swap over when the demand for 94 octane is bigger.

    • Not only can you have it, you do. Amazing opportunities await you. Simply open an FBO, put up a pump, and watch the dollars roll in.

  10. I have a question. What happens to the companies that currently produce the lead for 100LL once 100UL becomes the law of the land? Are they currently maneuvering behind the scenes to protect the only captive lead market they have in the world?

    • Your question should be what happens to the company (singular) that currently produces TEL… There is only one place it is made, and that is a singe plant in England. Ethyl Corporation, who invented the TEL process, sold out decades ago when they saw the motor gasoline market disappearing. By the way, Shell Oil owns part of the current operation, which might explain Shell’s lack of enthusiasm for unleaded Avgas. They participated in the FAA’s PAFI competition, but bailed out when they saw what a waste of time it was. GAMI’s George Braley declined to enter PAFI because he felt it was doomed to fail from the beginning. He was right. He also avoided applying for ASTM certification because it would have required revealing his proprietary blend to those same oil companies (Shell, et al) who sit on the ASTM’s review committee and who would be his main competition. After an agonizing 10+ year FAA review process, his STC says that G100UL has been tested, and approved, as a drop in replacement for 100LL in all spark ignition aircraft engines currently in use in GA aircraft. It can also be mixed in any concentration with 100LL so there is no issue with fuel contamination from mixing the two fuels. This is a classic David versus Goliath story, except that there are multiple Goliaths here (the FAA and the major oil companies who currently make a tidy profit from selling 100LL). If ASTM was a truly independent entity with no “skin in the game”, then perhaps things would be different. But it isn’t, and the FAA is not helping any with its ridiculous EAGLE program which is searching for something that already exists.

      • I can only imagine the incestuous relationships within the industry all protecting the cash cow. No wonder it’s taking so long. A whole lot of money protecting a whole lot more money. Now it all makes sense. Braly has got it right. George Braly is the Trump of the GA.

  11. The March 1, 2024 deadline in the letter is odd, because the consent judgment contains language that conditions the requirement on the new fuel being available “on a consistent and sustained basis at prices and on terms, in quantities and at times sufficient to meet demands of the customers of that Settling Defendant in California (‘Commercially Available’)….” I find it hard to believe that those availability conditions will be met two weeks from now.

    • The environmntal attorney is hoping the FBOs don’t read that part of the judgement! He/She is bluffing/bullying when it comes to that fast-pproaching date.

  12. I’m going to ask EAA why my Experimental RV6 with a Lycoming 0-360 engine – that Lycoming says can run on unleaded MoGas – would need an STC. It seems to me that if the engine maker says it will work – than that is the ultimate authority. Besides, are there going to be STC police at the fuel pumps asking for our paperwork? 🙂

    • Experimental aircraft are a tricky exception to the STC process, since there is no original Type Certificate that needs a supplement. The STC police you reference would be the guy who owns the pumps that sell you the fuel. Requiring you to own the STC is their way of protecting themselves from liability if you buy the fuel and then crash and start suing everyone.

      • Would be hard to police – esp at self service pumps unless the Tail number was checked against an STC database in real time. Fortunately, I’m in the midwest so it’ll likely all be sorted out before I face any threats of 100LL going away.

  13. …Also why woud each plane need an STC? Couldn’t an engine maker ceertify the new fuel will work? I certainly don’t have capabilities to pereform engine fuel testing. Maybe I’m missing something.

    • An STC is needed for both the engine AND the aircraft, since different planes have different fuel systems that may have components more sensitive to the different chemicals present. Also, some planes fuel systems are more prone to vapor lock, so lots of things to test and consider.

  14. Why can’t we just have UL 94 and anybody that wants lead in their fuel, they can buy it from the lead manufacture that was making the lead currently being added to the fuel. They can send the viles of lead to them and they can just add it to the Fuel, just like prist fuel additive is added to fuel.
    That way they don’t hold the users that don’t need 100 octane hostage to a more expensive Fuel. They can always modify their aircraft in the future to use the 94 UL.

  15. Chris D’Agosta SWIFT 94UL’s organization is only in a ‘panic’ about the fact that Braly GAMI 100UL fuel is most likely going to make it to the retail marketplace “soon” and with a State Court Oder/ Consent Order in place that blesses it as a ” go to fuel ” for compliance of that order- first out of the proverbial gate.
    STC approval- for GAMI 10UL fuel means : FAA sanctioned and approved. Period.

    It does NOT mean that “The FAA does not certify or approve fuel in the marketplace. Industry does,” D’Acosta told AVweb in an email.

    Pure Baloney on the part of D’Acosta SWIFT 94UL $$$

    Obviously, D’Acosta is trying to claim that only ASTM sanctioned and blessed fuels should make it to the marketplace $$$ and that of course would be SWIFT 94UL fuel only $$$ and thus moving the dial to FY 2030 in their favor under an ASTM program ONLY.

    Why did SWIFT D’Acosta STOP their further development /testing of SWIFT 94UL?

    Was it because UND stopped using SWIFT 94UL?

  16. My understanding is the G100UL developed by GAMI is based on a fuel the military developed at the end of WW2. I think this is why GAMI was so quick to come up with the formulation; although it took 10 years of research to convince Feds it was OK. And if I remember correctly, the military version was 130 octane. I would love to try the G100UL fuel in my experimental. Maybe I can run further lean of peak?

  17. Maybe Acosta of Swift hasn’t been able to replicate GAMI’s formula still trying (hence the ASTM) and the LGB FBO Castagna is in control of it all at least for now if this doesn’t scream conflict of interest I don’t know what does! sounds like $$$ is involved in it all. shameful