US Says Lead Emissions from Small Piston-Engine Aircraft Pose Public Health Danger

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October 18, 2023

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by David Shepardson (Reuters) The U.S Environmental Protection Agency on Wednesday issued a final determination declaring that emissions from aircraft that use leaded fuel pose a danger to public health, following years of study.

Commercial aircraft use jet fuel, which does not contain lead. Aircraft that do use leaded fuel are typically small piston-engine planes that carry two-10 passengers and are around 45 to 47 years old.

"The science is clear: exposure to lead can cause irreversible and life-long health effects in children,” EPA Administrator Michael Regan said in a statement announcing that the agency was finalizing a decision proposed in October 2022.

Children's exposure to lead can cause irreversible and life-long health effects, the EPA said.

Emissions from the 190,000 U.S. privately owned airplanes operating on leaded fuel account for about 70% of the lead entering the atmosphere, according to prior U.S. government estimates.

The EPA said it and the Federal Aviation Administration have begun "work to consider regulatory options to address lead emissions from aircraft engines."

The EPA's review of lead emissions from aircraft dates to 2006, when it received a petition asking for regulation of lead emissions from privately owned airplanes. The agency opened a proceeding in 2010, and in 2015 said it planned to issue a final endangerment finding in 2018.

While levels of airborne lead in the United States have declined 99% since 1980, piston-engine aircraft are the largest remaining source of lead emissions into the air.

The FAA in 2022 announced a new initiative outlining how to safely eliminate the use of leaded aviation fuel by the end of 2030 without adversely affecting the existing piston-engine fleet.

Reuters first reported in January 2022 that the EPA was again reviewing whether emissions from piston-engine aircraft operating on leaded fuel contribute pose a danger to public health. READ MORE

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Excerpt from U.S. Environmental Protection Agency: Protecting children’s health and reducing lead exposure are two of EPA’s top priorities. EPA has been investigating emissions of lead from aircraft operating on leaded fuel and the impact of these emissions on lead air pollution, including assessing lead concentrations in air near airports and evaluating the potentially exposed population. The majority of aircraft that operate on leaded fuel are piston-engine aircraft. These are typically small aircraft that carry 2-10 passengers. Jet aircraft used for commercial transport do not operate on a fuel containing lead.

The EPA has issued a final determination that lead emissions to air from certain aircraft engines cause or contribute to air pollution which may reasonably be anticipated to endanger public health and welfare. Aircraft that use leaded aviation gasoline are primarily piston-engine aircraft.

With this final determination, EPA now becomes subject to a duty to propose and promulgate regulatory standards for lead emissions from aircraft engines. The FAA is also now subject to a duty to prescribe standards for the composition or chemical or physical properties of aircraft fuel to control or eliminate aircraft lead emissions.

As EPA develops proposed emissions standards, it will consult with FAA and use the public rulemaking processes that include notice and comment and an opportunity for a public hearing. EPA and FAA are committed to working together and with the full range of stakeholders to address this issue.

For information on FAA’s work to safely transition the piston-engine aircraft fleet to unleaded fuel

Excerpt from National Business Aviation Association: A coalition of aviation stakeholder organizations issued the following joint statement regarding the U.S. Environmental Protection Agency’s (EPA) endangerment finding on lead in aviation gasoline (avgas) issued on Oct. 18.

“We are working with the administration toward the ultimate elimination of lead from avgas, and this finding mirrors and reinforces our shared goal of, and plan for, an unleaded fuel future. This finding is another step in the process, with rulemaking and other regulatory steps still to come, for developing and deploying viable unleaded avgas alternatives. We remain committed to removing lead from avgas by the end of 2030 or sooner, and are making considerable progress toward the introduction of market-viable high-octane unleaded replacement fuels that meet the safety performance needs of the entire U.S. fleet of piston aircraft.

“It is important that the flying community and the public understand that aviation safety depends on an orderly, nationally coordinated transition to unleaded avgas. The premature removal of an essential fuel that many aircraft require for safe operation, before a replacement is available, would compromise the safety, efficiency and economic viability of the U.S. airspace and airports, the general aviation industry and transportation infrastructure.

“While the EPA finding is a key step in the process, the EPA is not given the authority to ban, regulate or limit aviation fuel. Instead, the EPA’s finding triggers further deliberate rulemaking by FAA as the nation’s aviation safety regulator to ensure the successful development and deployment of viable unleaded avgas alternatives, given the critical safety and other issues at stake.”

The coalition of aviation stakeholder organizations include:
American Association of Airport Executives (AAAE)
Aircraft Owners and Pilots Association (AOPA)
American Petroleum Institute (API)
Experimental Aircraft Association (EAA)
General Aviation Manufacturers Association (GAMA)
Helicopter Association International (HAI)
International Council of Air Shows (ICAS)
National Air Transportation Association (NATA)
National Association of State Aviation Officials (NASAO)
National Business Aviation Association (NBAA)

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Founded in 1947 and based in Washington, DC, the National Business Aviation Association (NBAA) is the leading organization for companies that rely on general aviation aircraft to help make their businesses more efficient, productive and successful. The association represents more than 10,000 company and professional members and provides more than 100 products and services to the business aviation community, including the NBAA Business Aviation Convention & Exhibition (NBAA-BACE), the world’s largest civil aviation trade show. Learn more about NBAA at nbaa.org. READ MORE

Excerpt from Washington Post: The move puts the Biden administration in the middle of a brewing fight over how long airports — particularly smaller ones — can continue selling leaded gasoline, despite the health hazards from this powerful neurotoxin. More than 170,000 smaller planes, known as piston-engine aircraft, still use leaded gasoline, according to the EPA, and there is an ongoing dispute about how quickly this form of fuel can be phased out at thousands of airports nationwide.

The agency first proposed the move last year. It is a formal step known as an “endangerment finding,” and it now obligates the agency under the Clean Air Act to set new rules on what aircraft engines can emit.

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“The science is clear: exposure to lead can cause irreversible and lifelong health effects in children,” EPA Administrator Michael Regan said in a statement. “Aircraft that use leaded fuel are the dominant source of lead emissions in our air.”

Now that the EPA has made its determination, the Federal Aviation Administration said Wednesday that it will move forward with rulemaking aimed at controlling or eliminating aviation lead emissions from piston-engine aircraft.

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That work is happening as Congress also considers a long-term reauthorization of the FAA, including a bipartisan proposal that passed the House that would effectively require small airports to continue selling leaded gasoline.

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Commercial jets do not use leaded fuel, so the rules would affect only smaller planes that fly two to 10 passengers, the EPA said. On average these aircraft are nearly 50 years old and were originally designed to run on leaded fuel as a way to prevent engine trouble in flight.

While the planes are only a small subsection of the aviation industry, the agency said their emissions still pose risks near their airports, many of which are mostly in or near poor or minority communities. That includes more than 5 million people, of which about 363,000 are children 5 or younger, according to EPA figures.

Rep. Ro Khanna (D-Calif.), who has long raised concerns about the use of lead fuel in aviation and its impact on local communities, including one in his district, welcomed the EPA’s determination.

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In the interim, the FAA said it also encourages industry to take steps that can help reduce the impact on communities, including the early adoption of alternative unleaded fuels and the management of lead emissions by encouraging pilots to perform engine warm-ups and preflight tests in areas farther from populated areas.

The agency has been working with the general aviation community on ways to eliminate leaded aviation fuels used by piston-engine aircraft by the end of 2030. One key goal is to identify at least one unleaded fuel that can be used safely by general aviation aircraft.

Lead exposure can cause behavioral problems, lower IQs and slow growth, the EPA said. The agency has been trying to strengthen rules against lead pollution, partly in response to a new scientific consensus that lead can harm children at even the most microscopic levels. READ MORE

Excerpt from Washington Post: The language in the bipartisan FAA bill, which the House overwhelmingly passed last month, prioritizes the status quo over the quick transition activists desire.

The House version of the bill would require airports that receive federal grants to continue selling the same kinds of fuels they sold in 2018 in perpetuity.
The Senate version would require these airports to continue selling the same fuels they sold in 2022, with a sunset date of 2030 or whenever unleaded fuels are “widely available.” READ MORE

Excerpt from General Aviation News: The U.S. Environmental Protection Agency (EPA) has given a $776,636 grant to the California Department of Public Health that will “provide technical assistance to general aviation airports in California in disadvantaged communities to support the transition from leaded aviation gasoline (avgas) to unleaded avgas.”

The move follows a recent determination by the EPA that “emissions of lead from aircraft that operate on leaded fuel cause or contribute to air pollution which may reasonably be anticipated to endanger public health and welfare under the Clean Air Act.”

The technical assistance California Department of Public Health will provide using the grant includes voluntary business roundtable discussions, training, and developing educational materials and case studies.

“The proposed project aims to improve human health and the environment in disadvantaged communities identified through the state’s CalEnviroScreen by reducing lead emissions that may harm them,” EPA officials said in a press release.

The grant is one of two pollution prevention grants in California that EPA will fund this year—the other going to the University of California at Los Angeles—and was made possible by President Biden’s Bipartisan Infrastructure Law.

EPA’s Pollution Prevention Grant Program advances President Biden’s Justice40 Initiative, which aims to deliver 40% of the overall benefits of certain federal investments to disadvantaged communities that are marginalized by underinvestment and overburdened by pollution, EPA officials explained.

Between 2011-2021, EPA’s Pollution Prevention program issued nearly 500 grants totaling more than $50 million, which have helped businesses identify, develop, and adopt pollution prevention approaches. These approaches have resulted in eliminating 19.8 million metric tons of greenhouse gases, saving 49 billion gallons of water, reducing 917 million pounds of hazardous materials and pollutants, and saving more than $2.2 billion for business.

President Biden’s Bipartisan Infrastructure Law is boosting these efforts by providing $100 million to support the program’s continued efforts. Thanks to this federal investment, state and Tribal programs that are awarded grants will not be required to provide matching funds, which has helped expand access to these resources and broadened the applicant pool, EPA officials added.

Read more about P2 and the P2 Grant Program at EPA.gov. READ MORE

Excerpt from AvWeb: The lawyer for a California environmental group says a court settlement that will mandate the sale of G100UL avgas will not necessarily prevent FBOs from also selling 100LL. Mark Todzo, who represents the Center for Environmental Health, clarified part of his December 2023 letter to FBOs and fuel distributors informing of the imminent commercial availability of G100UL. In that letter Todzo said G100UL “can and should serve as a lower lead replacement for the 100LL fuel you are presently distributing” but told AVweb the agreement does not expressly stop fuel businesses from selling 100LL also. “They just need to make [G100UL] available for sale.”

George Braly, whose company General Aviation Modifications Inc. developed the unleaded fuel, is also a lawyer and said his reading of the consent agreement is that it compels the businesses and distributors to sell the fuel with the lowest lead content available. He said it says nothing about them being able to sell anything else. Regardless of the legal semantics, Braly said practical considerations will exclude 100LL from most airports in the state. He said the vast majority of fuel sellers have only one gasoline tank and pump. Adding a second tank will cost between $800,000 and $1.5 million, and getting all the permits and approvals will take up to three years. Vitol Aviation, which is making the fuel under license, intends to have it commercially available to California distributors and sellers in the first half of this year. READ MORE

Excerpt from AvWeb: We in aviation tend to view this as an interesting bun fight between the fuel establishment and some newcomers to the industry that has no consequences since 100LL continues to be plentiful at all the places we’re used to finding it. Indeed, that’s a fundamental tenet of the Eliminate Aviation Gasoline Lead Emissions group, maintaining a ready supply of 100LL while all the issues surrounding the transition are sorted out.

And that’s where Lori Shepler enters the picture. A couple of years ago, she dropped her now 7-year-old twins off at a school next to Long Beach Airport with more than the usual trepidation of the parental jitters that go along with that milestone. When her daughter (the other twin is a boy) was a baby, she had cancer surgery and underwent chemotherapy. The family just celebrated her five years in remission.

Meanwhile, the flight schools that line the ramps at Long Beach were responding to a massive increase in flight training demand, and she says on an average day there’s a landing and takeoff about every minute during school hours. Not long after that first day of school, Shepler was horrified to find out that lead was coming out of their exhaust pipes.

The attitude of some in aviation is that the amount of lead being released by GA is so small, relatively speaking, that there’s no real health hazard. That’s not to say there isn’t support for getting lead out of avgas, but we’re more concerned with the effect on valve seats and other engine components than the known effects of lead on human health.

For Shepler, the airplanes ceased to be a mere annoyance. They became spewers of poison that were unleashing toxins on a little girl who had already been through so much. Getting to school was such a victory and now it became, in Shepler’s mind, an existential threat.

At this point, it’s fair to ask why she didn’t just switch schools, but there’s an ex and a family court judge involved who agree that the lead emissions are not a threat that justifies moving schools. Shepler will be fighting that position in court in June.

Meanwhile, as Shepler researched more and called up the principal players in the current impasse, she grew more frustrated and is now infuriated since the solution to her problem is at the Vitol refinery instead of flowing from the pumps at Long Beach.

“It’s concerning that it’s being stopped,” said Shepler, whose quiet and respectful manner has already caused some to underestimate her. One of the fuel leaders she spoke with at first dismissed her as a “housewife” but he doesn’t do that anymore. Shepler is a Pulitzer Prize-winning former photojournalist for the Los Angeles Times and she’s using all her skills and contacts to fight this battle.

To that end, she’s helping organize a protest this coming Thursday (May 16) to raise awareness about the lead issue. Other groups who are more concerned about noise will also be there. Shepler has had some success in getting the local media interested in the issue in the past couple of years. Ironically the LA Times has yet to bite but the opposition Orange County Register did a major feature as have smaller publications in the immediate area.

But among the media expected to attend the Thursday protest is the local CBS affiliate. Depending on what kind of news day Thursday turns out to be the story might have legs beyond LA (and might wake up the Times, too).

Shepler has witnessed the amazement that many people express when they learn that there is still lead being used in fuel. The knowledge is being used by groups who are less concerned about the health effects of lead than the noise they are enduring or the profits they are missing because of their local airports. Lead emissions are now a standard part of the argument for anti-airport groups and that is helping to spread the knowledge. Shepler is trying to get one of the national news magazine shows interested in the story.

Meanwhile, she continues to attack her part of the battle with calm logic. She’s taken soil samples near the airport and all have lead. A few are right on the threshold where the EPA starts taking notice. She continues to liase with other groups that have formed in other areas of California that are fighting their own regional efforts, and that has resulted in a bill moving through the legislature that would ban leaded avgas.

But the real kingpin in what happens in California rests with the Center for Environmental Health. As we’ve reported, CEH has a consent agreement that compels the several dozen FBOs that are signatories to begin offering a lower lead alternative to 100LL as soon as it becomes “commercially available.” CEH can have a major influence on whether G100UL is defined in that manner, but so far it has not commented publicly on what, if anything, it intends to do. By the way, I’m a little ticked that Shepler can call and talk to CEH and their lawyers at will but they’ve so far ignored me. She offered to put in a word for me. Housewife, huh?

Shepler of course, doesn’t care who wins the fuel battle, who makes money or how it all shakes out. She just knows that when some kind of unleaded fuel gets into the tanks at Long Beach, one of her big worries and a source of family strife just disappears. But she also doesn’t want others to have those worries when the solution seems so simple.

“I just want the lead to end,” she said. “I think this is an important thing.” READ MORE

Excerpt from AvWeb: The Center for Environmental Health (CEH) appears poised to challenge in court the National Air Transport Association’s assertion that General Aviation Modifications Inc.’s G100UL is not commercially available. “G100UL has been approved by FAA and is now in production. There are approximately 1 million gallons available for purchase and distribution into California,” CEH’s lawyer Mark Todzo said in a statement to AVweb. “It is therefore commercially available as that term is defined in CEH’s Consent Judgment.”

That judgment, which settled a lawsuit by CEH against dozens of FBOs and fuel distributors, requires them to sell a fuel with lower lead than 100LL as soon as one becomes commercially available. “The Consent Judgment has an enforcement provision, so if the distributors refuse to distribute G100UL or the FBOs refuse to offer it for sale once it is being distributed into California, the Court will ultimately decide whose interpretation of ‘commercially available’ is correct,” Todzo said. “Nothing has been filed with the Court, yet.” The City of Livermore, near San Francisco, may be the first test case, however.

At the regular meeting of the city council on Monday, (video of meeting here, fuel discussion starts at 25 minutes) a resolution was passed amending the definition of aviation fuel (full text below) and including the provision that “the fuel must have an industry standard detailing specific requirements for the quality and safe use of the fuel (i.e. ASTM) where the fuel is also accompanied by risk mitigation protection with established product liability insurance coverage provided by the manufacturer or distributor.” GAMI has not obtained an ASTM International specification for G100UL but does have an FAA STC that allows its use by virtually every gasoline-powered engine in FAA certified airplanes. Vitol Aviation, the licensed manufacturer of G100UL, says the fuel it has stockpiled is fully insured and is, in fact, for sale.

Aviation fuel consultant Paul Milner told the council that the ASTM specification doesn’t provide indemnification and is not a requirement for fuel to be sold. He said the amendment therefore delays the sale of unleaded fuel at the airport when the intent of the ordinance is to speed it up. He also cast doubt on the objectivity of the ASTM process, noting that oil companies fund participation by their employees on the committees “to protect, defend and establish their rights in the marketplace” and that council should “carefully assess committee participants’ motivations.”

Acting Airport Manager Benny Stuart appeared to contradict the ordinance requirement for an industry standard, saying the STC was enough to allow the sale of G100UL. “GAMI 100 would be allowed under this ordinance,” he said. He also said that while G100UL is a drop-in replacement for 100LL it has not been tested for mixing with Swift 94UL, which is widely available in the Bay Area and might be an issue for visiting aircraft needing fuel.

Pete Sandhu, who runs Five Rivers Aviation, the FBO at Livermore, said customers don’t want G100UL because of the $300-to-$700 cost of the STC, and he predicted that two other 100 octane unleaded fuels in development will force G100UL out of the market in Livermore. VP Aviation is predicting its 100-octane fuel will have FAA fleet authorization by the end of 2025 while Swift Fuels has not set a timeline for STC and ASTM approval of its 100LL replacement.

Sandhu said his customers have made up their minds. “No one will buy [G100UL] and it’s soon to be replaced,” Sandhu said, noting that Swift’s 94UL, which cannot be used by some aircraft, is in use at neighboring airports and is what Livermore customers want. “The market has decided that Swift is the preferred product.” READ MORE

Excerpt from AvWeb: An effort to speed up the transition to unleaded avgas has emerged in a state where elected officials are on record as trying to delay it. In an op-ed published in the Anchorage Daily News, the Alaska Community Action on Toxics says a drop-in replacement for 100LL is available now (G100UL) and two others are pending (Swift and VP Aviation) and calls a recent statement by members of the Alaska House of Representatives “full of falsehoods.”

The statement calls on House members to support a resolution giving Alaska an extra four years to comply with the apparent FAA/EPA agreement to have a fuel ready by 2030. The recent FAA Reauthorization did give Alaska an extra two years to get it done but the House members say that will “potentially devastate both commercial and private piston engine-powered aircraft operations.” Among the allegations made by the House initiative is that “many small piston engine aircraft could face costs of up to $100,000 per unit, rendering them economically unfeasible and jeopardizing the existence of general aviation in Alaska.”

Of course, canceling GA in Alaska is a non-starter. Many isolated communities in the state are only reachable by air or on foot. Most of those places are populated mostly by indigenous people and that puts them disproportionately at risk from the effects of lead emissions. “With so many Alaskans put in harm’s way during aircraft operations, we might expect that our elected officials would push for the use of an unleaded alternative,” the op-ed says. “Instead, they are seeking to entrench leaded avgas by trying to undo EPA’s endangerment finding in Congress and to exempt Alaska from actions that could eliminate harmful lead emissions.” READ MORE

Excerpt from AvWeb: Tensions flared briefly at a forum on progress toward an unleaded replacement for avgas on Monday. During the public comment period after formal presentations, Tim Roehl, president of General Aviation Modifications Inc., challenged a couple of points made during the presentations of members and support staff from the End Aviation Gasoline Lead Emissions and told the crowd, smaller than in previous years, that contrary to assertions made during the formal part of the forum, GAMI’s G100UL is indeed ready for distribution and sale. EAGLE member Pete Bunce, president of the General Aviation Manufacturers’ Association, stood up and dismissed Roehl’s assertion. “I totally disagree but that’s a discussion for another day,” said Bunce.

In earlier comments, Bunce said his organization is adamant that any new fuel will be approve through “transparency and a peer reviewed process” which has traditionally been done through ASTM International. “Transparency is so absolutely vital for us,” said Bunce.

Refiner Vitol Aviation has 1.3 million gallons of G100UL in tanks in Texas and says it has been completed vetted as ready for sale through its STC. GAMI and Vitol have consistently said the FAA approval of an STC covering all gasoline engines on the FAA registry satisfies all the regulatory and safety requirements to begin retail distribution of the fuel, but there are critics who say it needs a consensus standard determined by an independent organization like ASTM to satisfy concerns about materials compatibility. READ MORE

Excerpt from AvWeb: The only candidate trying to develop an alternative to 100LL that's following the clearly preferred method of obtaining approval says it's impossible to make a "drop-in replacement."

The company that has received an FAA STC approving its high-octane fuel for all spark ignition gasoline aircraft engines and all airplanes that can instantly replace 100LL hasn't been able to sell it in quantity because fuel distributors refuse to carry it.

The third candidate that says its fuel is better than both those hasn't moved the needle on getting the approvals it needs.

All three of them have been accused of lying about the others to the point where consensus on anything will be next to impossible (there's that word again).

And the whole process seems to be under the control of a few specialized trucking companies, who appear, at this moment anyway, to be in control of whether any of the fuels eventually get to market.

I guess the big question is where we go from here.

There are those who favor blowing up the whole process and starting over and I admit some sympathy for that cause. From the start there have been allegations of bias and even corruption at work from all corners and the lofty goals of the Piston Aviation Fuels Initiative (PAFI) and End Aviation Gasoline Lead Emissions (EAGLE) to have this Coca Cola moment and work together in harmony to clean up piston aviation has devolved into name-calling and backstabbing.

We have a detailed argument listing the wrongs that have been perpetrated and suggesting that the FAA clean house at EAGLE to eliminate anyone who might have a conflict of interest. Since that would effectively require the resignation or firing of virtually everyone there, it seems impractical. The fallout from that nuclear option would inevitably infect any new process that hoped to reach consensus on, well, how to reach consensus.

And I guess that's why it's probably the inevitable and most efficient route to a new fuel. Democracy, free speech and free enterprise be damned. Someone needs to take charge here and that is the FAA. The agency needs to take responsibility for the process of approving the new fuel. Kumbaya, baby.

As it stands there are three different evaluation processes for three different fuels.

General Aviation Modifications Inc's G100UL has been approved by the FAA through the supplemental type certificate process and is theoretically ready to use in any gasoline engine in any aircraft except helicopters. The STC is problematic in that it requires aircraft operators using the fuel to purchase the STC. GAMI is also declining to pursue a fuel specification through an industry consensus process, such as ASTM. It doesn't trust ASTM and notes that the FAA made a specific determination that the certification meets or exceeds the testing standards for ASTM. And that's where the trucking companies enter the picture. They won't touch a fuel that doesn't have an ASTM spec and it would appear there's nothing anyone can do about that, at least not now.

It's not clear exactly why the fuel distributors are blocking sale of G100UL. All of their arguments about compatibility, liability and insurance availability have seemingly been answered and the FAA is unequivocal in its evaluation of GAMI's fuel.

In the STC for G100UL, the FAA said the fuel is not only better than 100LL, it's been tested to higher standards than other fuels. "The FAA has, in fact, made a determination that this Specification and Standard for a High Octane Unleaded Aviation Gasoline provides not only an equivalent, but, in fact, an enhanced level of quality control of the properties and performance of the aviation gasoline produced under this specification and distributed throughout the supply chain, as compared to the traditional governmental, military, or industry voluntary consensus-based standards (including ASTM) which have previously defined and controlled the production and distribution of aviation gasolines use for spark ignition piston engines," the FAA said. The STC and fuel spec are both posted on the GAMI website.

The other thing to note is that G100UL has been around for more than a decade. It's been used in the GAMI-owned SR22 for 12 years and run in aircraft ranging from small experimentals to the 2,000-horsepower radials in a Douglas A-26 Invader. LyondellBasell was hoping to make a splash with its UL100E at Oshkosh by sponsoring the fuel for an entrant in the AirVenture Cup Race but that fizzled when the engine blew in the Lancair for reasons unrelated to the fuel.

So far, doubts have been cast about G100UL's overall suitability as a 100LL replacement, but I haven't seen any significant evidence that it won't perform as such. The biggest knock on it is that it relies on some pretty nasty chemicals to achieve the high level of performance it seems to have achieved, but I doubt the other two contestants are any less noxious. Gasoline is a horribly toxic stew of harmful substances and you really should wear rubber gloves when you do your preflight fuel check. There was a brief controversy ignited when the fuel bladder in AOPA's fuel test bed Beech Baron started leaking at AirVenture. The leak was traced to a patch on one of the decades-old bladders and GAMI says it had nothing to do with the fuel.

LyondellBasell is going through the full congressionally mandated PAFI process that will lead to "fleet authorization" and an ASTM specification. This is clearly the method preferred by the board of EAGLE. It ticks all the boxes for evaluation and it would be just so damned convenient. Too bad it doesn't work. The company says there is no way for a fuel that doesn't have lead or manganese in it to boost its base octane level to 104 or more, which it says is required for a true "drop-in replacement." Manganese has been tried as a lead replacement but it clogs up combustion chambers.

LyondellBasell says only about 80% of engines will be able to use unleaded fuel without performance limitations or even mechanical modifications to prevent detonation. The big problem is that the 20% of engines orphaned include the big bore Continental 550 and Lycoming 540 series engines that actually use more than half of the avgas burned in the U.S. LyondellBasell says those issues can be addressed mostly through paper modifications, but there will be performance and fuel consumption compromises. It is not, therefore, the "drop-in" replacement that is the stated goal of both PAFI and EAGLE. LyondellBasell says it's going to continue with the process because it's the only process that can lead to a fuel that can be used by all aircraft.

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Let's not forget that all this came about because of an endangerment finding by the Environmental Protection Agency that will outlaw lead in aviation fuel. The only reason we're not hearing from the EPA is that the FAA cut a deal promising to have the unleaded replacement by 2030. Considering the process made in the four years since those handshakes were made, it suddenly doesn't feel like six years is very much time at all.

Clearly, the current process is a failure. Far from engendering a cooperative and collaborative approach to what seems like should be a straightforward engineering challenge, it has collapsed into a schoolyard brawl in which the principal is missing in action. The FAA needs to take action to get this back on track, and I would suggest a standardized evaluation process that tests each fuel in the same ways and to the same criteria is a place to start.

Such a move will undoubtedly create even more controversy but it's a painful necessity to ensure aviation has a say in its future fuel. The EPA already has the authority and ability to mandate the elimination of lead in avgas. It's not going to wait indefinitely to use it. READ MORE

Excerpt from AvWeb: Last week's blog was more of an update on progress so far on the replacement of 100LL with unleaded high-octane aviation fuels. In the comments section a reader who uses the title BestGlideSpeed gave a long list of questions and criticisms of General Aviation Modifications Inc.'s (GAMI's) G100UL.

Many of the points made by BestGlideSpeed have been made by others and others we haven't heard before. GAMI founder and Chief Engineer George Braly has addressed them in a point-by-point response to the post.

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As an engineer developing new products for market, I understand that a typical, successful development project always includes the following:

1. Unrealistic demands of what the new product must be able to do.

Not in the case of G100UL. The original design criteria, set out in writing to the FAA in the spring of 2011, were each fully met, and even exceeded.

2. A never ending system of hurry up and wait.

Yes. There has been a lot FAA imposed “waiting” and not a lot of “hurry up”

3. Unrealistic demands that after everyone sat on their hands burning up the clock, you must now save everyone else’s bacon and get the ball across the finish line in record time.

No such urgency from the FAA has yet come to light.

4. Individuals who have no understanding of the science, industry, or use case are the ones setting the project priorities.

There has, at times, been some of that from the FAA. But mostly the impediments have been designed by the proponents to simply slow the G100UL avgas project down or to stop it, completely.

5. Self interested individuals continually ignore realities and proclaim “just go with my favorite answer now” because the unresolved concerns fall outside of their very limited set of priorities.

A lot of that very recently with respect to the coverage of the last 2% of the fleet of aircraft - rotorcraft.

6. The list goes on ad nauseam - and that is when things go well.

Things went “well” from 2012 to 2015. Then stagnated for four years. Then went backwards for 6 months. Then, beginning in July, 2020, the Washington AIR-1 assigned a really GREAT new team of engineers and we managed to finish the project in 24 months.

A project that the government gave ten years to resolve is only four years along.

The scope of that government project included TWO PATHWAYS TO SUCCESS: a) The PAFI / EAGLE project and b) The STC pathway. The second of those two pathways is now a resounding success with every single spark ignition engine in the FAA database approved to use G100UL Avgas. No exceptions!

From my perspective, I am impressed with the progress that has been made in that amount of time.

Respectfully, I would suggest that almost no person in the FAA who is not financially or career “motivated” with affiliation to the manifestly failed PAFI / EAGLE program would agree with you. The taxpayers have spent nearly a quarter of a billion dollars on the failed UL AvGas/PAFI/EAGLE programs over the last 20 years. The taxpayers have absolutely ZERO to show for that expenditure. Ronald Reagan once observed that there is nothing that lasts so long in Washington as a “temporary program.”

The fact that Russ is proclaiming all to be lost and we need a complete reboot with the FAA jack boot on the neck of fuel manufacturers to obtain it is just adding himself to the list as another obstacle to getting anything done.

On the contrary. Russ’s observations, and Paul Bertorelli’s from 18 months ago, are precisely on point.

I give kudos to at least one organization being honest enough to say that a “drop-in” replacement is not possible.

That statement calls to mind the old Chinese Proverb: One should not tell the Chinaman that he cannot do something he has already done! A full “drop-in” replacement has already been approved by the FAA. Any statement to the contrary is either based on a lack of knowledge, or some hugely contorted definition of the phrase “drop-in” to mean something very different than the meaning given to that term by the FAA and most other participants.

To accept that statement we have to understand what a “drop-in” replacement entails. It is easy to say “I fly behind a Jabiru engine and I don’t need the same octane as some of the big block engines, so let’s just go with XXX”, but that is not a drop-in replacement for the industry. Whatever replacement we ultimately come to will be a system of compromises.

There is no compromise with the use of G100UL Avgas. In fact, G100UL Avgas is able to allow enhanced performance of the existing fleet of high powered radial engines - - by allowing those engines to be up-rated in BHP back to their original war time military ratings.

Some of us will come out of this perfectly pleased, and some of us will be left out in the cold.

No one is left out in the cold - - except the major producers of 100LL who have tried to obstruct and delay any development of a “drop-in” replacement for 100LL.

Consider:
GAMI’s fuel is not approved for rotary wing. You cannot get rid of 100LL and leave all of the rotary wing aircraft grounded. News helicopters, med-evac, offshore platform,

Wrong. Every single rotary wing [gasoline] engine is already approved for use with G100UL Avgas. Robinson Helicopter (which makes 80% of all of the helicopters) has fully tested G100UL avgas using their independent test protocols that they developed for their testing of PAFI/EAGLE fuels. Robinson has told GAMI that G100UL Avgas is the only unleaded fuel to ever pass their rigorous flight test helicopter profile. Robinson has written a complete engineering report and that has been submitted to the FAA to facilitate the early addition of the rotorcraft airframes (the engines are already approved) to the Approved Model List.

. . . the list goes on and on. [If the “list goes on….” Then, please, send me an email and let me know what other items are “on the list.” gwbraly@gami.com.

GAMI’s fuel is approved by the FAA via STC - this approval only means that if I fly a certificated fixed wing aircraft, I am allowed to use it and not get busted by the FAA.

That is false. The FAA approval means the FAA has found the use of G100UL Avgas to be equally safe, or actually safer than the use of 100LL. Their words were: “… as good as or better’ than 100LL.

It is not an industry approval, and it by no means is a blanket mandate, indemnification, or adoption.

There is no such thing as an “industry approval.” Period. Parade Rest. Nor has there ever been. The purpose of an ASTM specification (by its own terms, in paragraph 1.1, is to facilitate the sale and purchase of 100LL by “purchasing agents.”

It is not approved by the engine manufacturers, it is not approved by the airframe manufacturers,

Actually, Cirrus has fully tested G100UL Avgas. Recently, the senior manager at Cirrus has told his staff and has told one of the industry groups that “Cirrus has no technical objection” to the use of G100UL Avgas.”

… it is not approved by the insurance companies.

Wow. What complete nonsense! ! ! You have been reading too many “statements” from Curt Castagna at NATA.

FACT: Each of the major distributors has directly advised GAMI directly, that they have obtained the same product liability insurance for their sale of G100UL Avgas as they have for 100LL. Two years ago, the insurers told one of the two largest distributors the following (at Lloyds, in London): “If the FAA approves G100UL Avgas, then Lloyds will insure it. No additional charge for the premium. FURTHER MORE, Vitol Aviation was able to add G100UL Avgas to its policy with no increase in premium.

… , and it is not approved by the fuel distributors/sellers.

Actually, each of the major distributors has reviewed the G100UL Avgas FAA approved specification and told GAMI that they had no objection to that specification. Note, distributors and sellers do not approve or disapprove of fuels. And none of them have stated to GAMI that they have any reason to ‘disapprove’ of G100UL Avgas .

The FAA has no authority to mandate via STC that Lycoming engines must run on GAMI fuel that distributors must sell it, and insurance companies must indemnify it. The STC only gives permission to the pilot to buy it.

Correct. Nor does the FAA mandate that Lycoming must approve the use of 100LL or UL94 or UL82. THAT is not the FAA’s job.

We have one fuel that proclaims itself the elixir of all aviation engines, but refuses to allow the industry to examine it.

WRONG. Wrong, again. And Again. From your series of false statements, it appears that you may be reading too many press releases from NATA and GAMA, and similar organizations. GAMI has in fact allowed the industry to examine G100UL avgas. Lycoming and Continental have each sent engineers to GAMI and have flown G100UL avgas and compared it back to back with 100LL and have each stated to GAMI that they cannot tell the difference in operation when compared to the use of 100LL.

We have another manufacturer that says we are working on the best solution we can, but there is no silver bullet and our solution will not be a drop-in replacement for 100LL. We have a third that is working on it but is keeping their efforts close to the vest.

That would be LyondellBasel/VP Racing and Swift Fuel. Both of the sponsors of each of those two fuels have acknowledged, publicly, that neither of those two fuels will be able to be used on the higher performance portion of the fleet (8.5:1 CR N.A. engines and turbocharged engines) without substantial engine modifications and/or limitations added to the operating instructions.

I doubt that GAMI’s fuel is as perfect as they claim.

GAMI has never claimed it is “perfect.” Please do not make false accusations.

There are too many red flags. In the end, there will be compromises.

Please elaborate and identify the “red flags” and the necessary “compromises” which you, in good faith, believe to exist?

We may need to move to multiple fuels to provide a simple well performing fuel to those who do not need such high octane, and a “compromise” version of 100LL that the EPA can live with in smaller quantities for the larger engines, rotary wing engines, and any others that absolutely require the higher octane.

We may need to choose a boutique fuel that gets us most of the way there, but only after modifications to the engines that require higher octane.

The thought embodied in the previous two paragraphs may well be some of the worst proposals and/or concepts for a “solution” to the TEL lead problem ever articulated in public. Either or both would be a disaster for general aviation piston powered aircraft owners.

Likely, we will need to kick the can down the road and extend the 10 years. The amount of lead contributed to the environment by aviation fuel is infinitesimally small when compared to the world’s annual consumption of lead - so small that is not measurable in the environment.

Yes, the lead contribution is small. But continuing to be a “lead denier” will likely not work out well. In addition, the benefits we have all enjoyed in the automotive world from getting rid of the lead will also take place in aircraft engines. Double or triple the oil change intervals. No more routine cleaning of spark plugs. Likely, in our future, greatly extended TBO’s. All of those are likely to occur.

There is no perfect solution, and typically it is not the first suitor to knock on your door. We have 10 years to fully develop every option and then make a well informed decision about the compromises that we will need to make as an industry.

Respectfully, if you think the States of California, Oregon, WA, CO. WI. NY, and a number of others are going to wait more than another 12 to 24 months, then you are not well informed with the activity going on in those states.

For those who want to see GAMI be central to that solution, my recommendation is that GAMI take advantage of the next few years to continue to perfect their product and completely satisfy the testing requirements of every industry group out there.

A) No “industry group” has even come to GAMI to make any suggestion for any further “testing”. B) Please provide some details as to what aspect of G100UL you believe needs to be improved upon?

They should resolve the limitation that excluded rotary wing.

The addition of helicopters to the AML STC is nearly completed. See the previous comments on that subject about Robinson.

They should be testing their fuel with Lycoming, with Continental, with Jabiru, with Rotax, with ASTM, with Cessna, and with Piper.

G100UL Avgas has already been rigorously tested to the FAA’s highest standards. Lycoming and Continental have both tested G100UL and found no deficiencies. Nor have they pointed out any to GAMI.

NOW HEAR THIS: ASTM DOES NOT TEST FUEL! ASTM considers testing done by fuel sponsors – just like the FAA – and then only writes a specification. Which is not approval to even put one drop of fuel in the wing of an aircraft.

They should include representatives of insurers and distributors in those efforts.

GAMI has done that for distributors. Insurers do not get involved in any such activity. Where on earth did you come up with THAT concept?

Sitting on their secret formula and saying “we don’t trust anyone” is doing themselves no favors while their competitors work diligently for a solution that the industry can openly embrace.

Obviously, once again in the long series in this response, you are not well informed. The complete specification for G100UL Avgas, Revision -12C9 has been posted on GAMI’s web site www.g100ul.com and, more specifically, https://www.g100ul.com/faq#specification since before Oshkosh. In addition, any of the distributors and/or OEMs that has asked to see that document have been furnished that document, over the course of the last several years. READ MORE