Congressional Subcommittee Meets In ‘Outrage’ Over Leaded Avgas


George Braly, co-founder of General Aviation Modifications Inc. (GAMI) and Chris D’Acosta, the CEO of Swift Fuels, both testified at a July 28 hearing of the members of the House Oversight Committee’s subcommittee on the environment. The hearing was called to address bipartisan “outrage” over decades of delay in phasing out leaded aviation gasoline, the sole remaining source of lead contamination among operators of internal combustion engines in the transportation sector. GAMI and Swift both have developed candidates for replacing 100 low lead (100LL) fuel with lead-free substitutes, but have faced regulatory headwinds that have stalled approvals.

Committee member Rashida Tlaib, a Michigan Democrat whose district is not far from Flint, where the water supply was famously contaminated with lead a few years ago, said of leaded aviation fuel, “This is a wakeup call. When planes from these airports fly over our communities, they are crop-dusting our neighborhoods with lead-poisoned air.”

Also testifying at the hearing was Cindy Chavez, commissioner of Santa Clara County, California, which recently became the first local government to eliminate refueling with 100LL, prohibiting its distribution on municipally owned Reid-Hillview Airport. While a 2020 study commissioned by Santa Clara County in 2020 found “a clear link” between lead exposure and proximity to the airport, a news story published by San Jose shortly after the study was released reported that, of the 17,000 children under 18 examined who lived within one and a half miles of the airport, 1.7 percent showed lead levels calling for “further testing and observation,” according to guidelines from the Centers for Disease Control and Prevention. The statewide average of children who meet the same criteria is between 1.5 percent and 2.6 percent depending on age, according to statistics.

“The levels are also similar to neighboring counties,” wrote reporter Vicente Vera. “North of Santa Clara County, 1.5 percent of Alameda County children were found to have elevated blood levels, while approximately 2 percent of Santa Cruz County children showed elevated lead levels, based on data collected in 2018 by nonprofit research organization Population Reference Bureau.” Subsequent studies of ground samples also failed to reveal elevated levels of lead within the confines of Reid-Hillview Airport. That study was originally reported by the San Jose Mercury News.

Representatives from the FAA and EPA did not participate in the subcommittee hearing, with member legislators referring to their absence as “unconscionable.” The EPA has scheduled a draft of an “endangerment finding” on leaded aviation gasoline for publication in October. A final version of the draft is expected a year later, with action on the finding anticipated to take up to eight years. The FAA did express commitment to a 2030 deadline to bring unleaded aviation gasoline online and plans to increase funding for the effort to $12 million (from $6 million) for the next fiscal year.

Mark Phelps
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. Maybe unleaded avgas, like Basic Med, will be legislated in by Congress instead of waiting for the FAA.

  2. I am perplexed as to how this hearing occurred without the FAA or EPA. Isn’t the House in recess now? I know that some members are traveling. Also, is the House oversight committee the right one to be holding hearings on this. Last, is GAMI now lobbying for faster elimination of leaded avgas? 2030 is a tight deadline as it is for many owners.

    • GAMI and Swift appear to be testifying that they have an unleaded 100-octane solution, but it is being held up by the FAA. I don’t think they are particularly lobbying for an earlier deadline so much as a chance to bring their products to market.

    • The House was in session all last week, summer recess started Monday for them.

      As for “how this hearing occurred without the FAA or EPA.” Well, that’s a really good question for both Agencies. I’d sure like to hear what they’re hiding from Congress. From everything I’ve read, GAMI jumped through more hoops than necessary and their fuel was basically certified by the office doing the testing. It was just sent up to the DC Office for the big boys to take credit. But they screwed the pooch for some reason….

  3. Spare me your hollow, self-serving outrage, politician, and make the FAA do their jobs instead of being either wholly negligent or intransigent obstructionists as has been the pattern.

  4. This sounds like more terrible epidemiological studies then reality. Its like the crap Wakefield put the world through with MMR vaccine and autism or the myths of banning DDT (see Silent Spring and/or Colson).

    • But DDT overuse did cause issues, and lead poisoning does “dumb down” kids (though they usually eat it, in the form of old paint.)

  5. As I’ve mentioned elsewhere, EAA STC’s for using Mogas (80/87 no lead gasoline) in most GA aircraft running 4 & 6 cylinder air cooled engines have existed for thirty years. Every new cylinder out there for the same past thirty years does not need lead for valve seat protection. And no lead, no ethanol, 90+ octane gasolines exist at many rural gas stations – at the pump – all across the country.
    What’s the problem?

    • “The problem” is many of us fly airplanes whose engines require 100-octane fuel – leaded or otherwise.

      • Fully understood. But nobody is suggesting that Avgas goes away when Mogas is added to the fuel options. Yes it will require an additional fuel system, but U-Fuel offers small turnkey, above-ground, self-service units for a modest sum.

        • Adding a mogas option would increase an airport’s costs, but wouldn’t increase fuel sales. It would just siphon off the 30% of low-compression fuel sales from the avgas pump.

          • And add it to the mogas pump. Net fuel sales will be the same or even increase as it is a pain to transfer fuel by car or truck to the airport.

            They are already losing a significant portion of those sales completely. I run through about 1500 gallons of mogas a year, nearly all not bought at the FBO because they do not carry it and leaded fuel is a maintenance nightmare.

            Most airports I visited with my low compression O-470-R had 80 and 100LL and a quite a few even had 100 Green when I first got my airplane in the mid 20th century.

            When 80 disappeared, I switched to 100LL on a steady diet and ended up with a bottom spark plug fouling requiring cleaning every 10 hours no matter how lean I ran the airplane. I got the mogas STC, got a transfer tank and switched to lead free alcohol free fuel, ran nearly 1000 hours past TBO.

            Airport FBOs had the facilities to carry at least three fuels (JetA, 80 and 100LL) for years. So what if it siphoned off 100LL fuel? They make the same or better markup per gallon on the fuel. The corner gas station sells 87, 91, 93, E15, E85 and alcohol free mogas as well as diesel. I’m pretty sure they make more money on the E0 as they charge a dollar or more a gallon more for it.

          • Art,
            As I understand it, the mogas sales at many airports were not sufficient to keep the mogas from going bad in the tank.

            Mogas is a local matter, not a national one. If your field has sufficient demand, then open a frigging pump and go into business. It’s allowed.

            If you are one of the jerks hoping to increase the value of their plane by ridding the world of high performance pistons, then I guess you can keep trying.
            After you succeed, no whining when there aren’t enough owners of certified aircraft to protect you from the next purge (not that we are doing that well now).

          • Not necessarily. Those using Mogas now are contributing zero income to airports and their fuel taxes are going to build the highway infrastructure, not aviation. As some have said, Mogas-ready aircraft use a smaller volume of fuel than those needing Avgas, so their switch to Mogas if available at airports would hardly be noticed in lower avgas sales. Small fuel systems can be leased. Better yet, let a private individual/business, flying club or FBO finance them so the airport has zero costs.

    • To expand upon Yars reply – most of the GA fleet (about 70%) can burn mogas.

      But those low-compression engines account for less than a third of fuel sales. Most avgas (also about 70%) is consumed by high-compression engines used in business/commercial operations. They consume more fuel per hour and fly many, many more hours. The aren’t flying patterns on the weekend when it “looks busy”. They’re somewhat invisible, flying hither and yon cross-country during the week when most of us ‘weekend warriors’ are at our day jobs. These planes can only run 100 octane fuel.

    • As for the “lead lubricates valve seats” theory – that was never true. Aluminum-cylinder heads have always used hardened valve seats. Not just in the past 30 years, but pretty much since the beginning. Aluminum is too soft for direct-machining valves seats like cast-iron heads.

      Even so, lead never lubricated anything. The spate of valve-seat recession that occurred when unleaded fuel was introduced to cars in the 1970s was primarily because of lower octane. When lead was used to boost octane it was common to add a bit more just to make sure it met the posted octane amount. So what most people bought was usually a bit higher in octane.

      But with unleaded fuel it was more difficult to meet the posted octane. As a result the gas dispensed was exactly the posted number, not a couple of points higher. As a result people were driving around on effectively lower octane than they were used to, resulting in more pinging, detonation… and valve recession.

    • The problem is finding non-alcohol contaminated mo-gas regardless of any available STCs. I had a low compression 0470 that would have been happy with mo-gas but it was simply not available or transport onto the airport was strictly prohibited

      • I ran into this problem at one airport which attempted to prohibit non-fbo fuel being brought onto the airport. This was contested and the airport lost. Please see FAA AC 150/5190-6 Exclusive Rights at Federally Obligated Airports Paragraph 4:” It is FAA policy that the sponsor of a federally obligated airport will not grant an exclusive right for the use of the airport to any person providing, or intending to provide, aeronautical services or commodities to the public and will not, either directly or indirectly, grant or permit any person, firm, or corporation, the exclusive right at the airport to conduct aeronautical activities. The exclusive rights prohibition applies to both commercial entities engaging in providing aeronautical services and individual aeronautical users of the airport. The intent of the prohibition on exclusive rights is to promote fair competition at federally obligated, public use airports for the benefit of aeronautical users. The exclusive rights prohibition remains in effect as long as the airport is operated as an airport, even if the original period for which an airport sponsor was obligated has expired.”

    • Ethanol free gasoline availability is highly variable and cannot be relied on. It’s very hard to find in my area. The stations that do have it (Rec 90) are often out.

  6. Grandstanding “outrage”! I’m shocked! FYI, Rashida Tlaib’s district is more than 50 miles from Flint but it does include DTW. As a Michigander, I don’t consider 50 miles to be “not far” from Flint. That said, using the word “Flint” when discussing any type of pollution is a powerful dog-whistle in political circles (especially within Michigan). She just won the primary election against three other candidates and will undoubtedly win in November.

  7. “Rashida Tlaib, a Michigan Democrat”
    “Cindy Chavez, commissioner of Santa Clara County, California,”
    they are very good with tyrannical resolutions…
    Yea right, “studies have show” hummmmmmm…
    It was done by who, what criteria was used, sample size, etc…
    Smells fishy to say the least…

    • The studies proved there was no problem of lead contamination around airport populations and showed the lead levels were the same throughout the state regardless of nearness to an airport. Simply ignorant, pandering political grandstanding.

  8. Be careful what you ask for. GAMI and Swift getting congress along with more government committees, agencies, and bureaucracies involved might get something done faster. But might also give us a solution that doesn’t work or costs a fortune to fill your plane.

  9. 91 AKI E0 Mogas is available all across the nation. currently shows 16,856 sellers of it. We just need airports to add a modest self-service fuel system and find a local fuel supplier to deliver it. U-Fuel makes the best ones. The Mogas does not have to come from an Avgas / Jet-A supplier. Mogas can power 80% of the piston engine fleet with Petersen STCs or all the new engines designed from the start run on it. This is not an either-or option. Keep Avgas too, as is typical at European airports, where pilots have had a Mogas option for many years. This would send a message to those worried about a minuscule amount of lead that we’re really serious. When GAMI, SWIFT or others get their fuel certified, swap the Avgas for it. Every gas station in the country has 3 grades of gasoline, diesel, and often also ethanol-free fuel. Why is this a problem for airports?

    • Mogas outsells avgas by roughly 1,000 to 1. With that kind of volume it’s easy to economically have multiple grades of gasoline. With mogas, most stations have only two flavors – high and low octane. All of the intermediate grades are just a mix of the two. About half or more also sell diesel fuel, primarily nearer interstate highways and other concentrations of diesel-power vehicles.

      Avgas sales are so much lower, and their inspection requirements higher, that it’s usually not economical to split the pie into two smaller pieces. Doing so would double an airport’s storage and delivery costs, but would not double fuel sales.

    • Lots of issues with Mogas, mainly it is not stable and secondly how do you keep ethanol out of it. They can make 94 UL which is the avgas they make now without the lead. Not sure why that cannot happen. As others have said the major users of avfuel are the high compression engines that need the 100 and that is the problem that needs to be resolved.

    • Slightly off-topic. I wish’s data was good but it unfortunately shows an abundance of very old listings almost anywhere you look. I have used the website to try and find ethanol-free gas on motorcycle rides and have had to remove several stations over the years.

  10. Some pilots I know have tried running E0 mogas in their O-360 powered experimental aircraft and on hot days, the results have not been good. As in engine failure (fortunately over an airport) and not being able to start. As a result of these experiments, they have 100 LL in one tank and E0 in the other tank “just in case”.

    This and other antidotes tells me one has to be very careful using E0 mogas in aircraft. Hopefully the GAMI and SWIFT fuels are better and not going to be priced over $10 / gallon.

    Are GAMI and SWIFT fuels based on petroleum products in anyway? If any of the fuel components are derived from fossil fuels, the stated policy from the current government administration is to eliminate fossil fuels which means GAMI and SWIFT fuels would be a non starter. Perhaps the FAA is grappling this this issue.

    What concerns me is when people with no idea what they are doing, as in legislators, get involved in trying to solve large, complex and complicated systems problems. The results are not good. Anyone try and order any parts lately?

    • Please define “engine failure”.
      Was it:
      1. Failed to produce needed or expected power
      2. Blew up/Reduced to scrap metal.

      There’s a difference.

    • My understanding is that G100UL is based on the same 94UL that 100LL is based on, but with different additives instead of TEL. I don’t know much about Swift, but I thought it was based on bio-renewables.

      In any case, don’t confuse the growing movement of trying to eliminate ICE-powered consumer vehicles with eliminating fossil fuels altogether. That’s a significantly bigger and complicated issue, and I don’t see it likely affecting aviation for quite some time. Certainly well beyond 2030.

      • Actually, G100UL is a different mix of existing chemicals. Instead of trying to find a new additive to replace lead like previous failed attempts, they found a new blend of hydrocarbons that has an inherently higher octane than the blend of chemicals in gasoline. This is why G100UL weighs more than 100LL (6.3lbs/gal versus 6.01 lbs/gal). But it also has slightly more energy per gallon (about 1-2%) so you can theoretically go a bit farther per gallon than 100LL.

        • While simultaneously reducing the overall range of your aircraft. 5% heaver, but 1.5% more energy dense is a net loser for range. It’s not a lot, but it’s there.

    • Hot day? CHTs? Cowling/cooling air flow? Fuel lines plumbing/routing? Fuel system design? Similar failures with 100LL?

      There have been many like tens of thousands of event free hours flown on mogas using both EAA and Petersen STCs. Anecdotes do not an exception make and correlation does not imply causation. A pilot I know had an E0 fueled loss of power too, but I doubt it caused the intake balance tube to crack venting the intake to the atmosphere at 60 hours past overhaul.

  11. That hearing was orchestrated by our Congressman (Khanna) and Zoe Lofgren (not a member of the Subcommittee) to help add passion to their project to close Reid Hillview Airport.. It was not to address potential lead issues at other airports.. It wasn’t even to address more significant sources of lead in Santa Clara County, like paint and plumbing in older homes, pesticide residues and legacy lead from autogas. That is why FAA and EPA didn’t bother attending. And Cindy failed to mention that by banning sales of 100LL, 90% of Flight Operations at RHV today are flying with unleaded UL94 (by actual count of tail numbers from Tower logs..). That means that whatever lead there was is 90% gone, and so with it is any reason to close the airport. Thus the shift to racial and economic injustice as new theory… And please remember that Mogas in California does not come ethanol free.. All gas for autos in the state must contain ethanol, so that is not an option…

  12. See “10 Mogas Myths”, GA News, online, March 16th, 2011. Looks like many still abound. Good thing Rotax, the world’s largest maker of aircraft engines, ignores the myths. 100% of its engines are designed to run best on 91 AKI E0 Mogas. Some airports here in the Southeast are selling it for around $5 per gallon. Stick the higher costs for high octane avgas required by a minority of aircraft to the flyers of light aircraft and you kill off the next generation of pilots. Everyone loses. Small fuel systems can be leased, for instance from U-Fuel.

  13. What I do not understand – why hasn’t Todd Petersen been invited to weigh in on this topic? For over 30 years he has done the bulk of aviation fuel tests on airframe / engine combinations required for his 100+ STCs, covering everything from Cubs to DC-3s. In one sense, he has been providing a safe, powerful, FAA-approved, highly available and affordable lead-free aviation fuel – Mogas – for the vast majority of piston aircraft. Perhaps AVWeb can interview the “Dean of Mogas” to get his take on things. I’m sure he has some thoughts on all of this.

  14. I’m surprised the FAA didn’t come to the hearing to brag about their record in killing off the piston aviation fleet altogether. No planes, no lead!

  15. The problem is, that there is no problem.
    Both CO2 and using low-lead fuels is not a real problem of concern in the context of global transportation.
    The problem is that some individuals disreguard both reason and porportion in order to put a check in a box that they have created. The same people prize that check in their box higher than tangible helping or creating (or even just leaving other people alone). It’s insideous and no one seems to have the guts to tell them to stop destroying.

  16. Perhaps he should be enraged by false information. A racetrack that went out in the 1980’s, as well as a chemical company, were in close proximity to the airport. Couldn’t the soil samples be possibly tainted by said structures? No, it must be the little aircraft running low lead fuel that were causing such high reading…..

    • Karrpilot, they were not looking for truth; they used paid studies to do extrapolations and correlations and then wrapped it up all up in scientific terminology to simulate a real study. I’ve read all the “reports” and all of them have logic errors and unsubstanciated conclusions. Junk science. Basically the city airport land is more valuable to them as another industrial park so what better way to close an airport than to scare people?

  17. Our airport is owned and run by the city. They have implemented “fuel flowage” fee for those of us who bring Mo-gas onto the airport. It is on the honor system and it is very reasonable charge so I, for one, don’t mind paying it. Our airport has a lot of Rotax engines and I understand that the ratio of those using Avgas to Mo-gas is about 50/50. I have no problem finding ethanol free Mo-gas and have not had a problem running it in my 582. I have learned to treat Mo-gas differently from Avgas. I do not let it sit in the tank for long and especially not in the carb for extended periods. If Mo-gas sits it will turn to varnish and clog your carb jets in a short period of time. I try to run my engine minimum of 2X per month even if I can’t fly for some reason. If the fuel companies could come up with an ethanol free unleaded that is more stable then maybe FBOs would start carrying it at the fuel farms which would then make a big difference in the leaded/unleaded ratio.