I recently joined a video conference updating the progress of the Eliminate Aviation Gasoline Lead Emissions (EAGLE) initiative, which aims to find an unleaded replacement for 100LL by 2030.
It was an interesting presentation, taking me back to the late 1990s when this whole process started.
If you do some quick math, you’ll realize this has been going on for more than 25 years. In those 25 years there has been a lot of talk and a lot of money invested.
The government and oil companies have invested millions and millions of dollars in research and development without a clear answer (with one possible exception).
Now I know most of you think that the government and oil companies have unlimited funds. Well, the government does have a fair amount but, in the end, someone usually needs to account for what is spent and what was accomplished.
And from experience, I can tell you that oil companies expect a return on their investment before too many millions are invested.
So, where are we after 25 years and many millions of dollars spent? Not that far from where we were 25 years ago, it seems to me.
During the most recent EAGLE update, the presentations by the engine and airframe manufacturers, including Textron Aviation, Piper Aircraft, CubCrafters, and Lycoming Engines, seemed like reruns of what I’ve heard before.
They were all in agreement that they need a new unleaded fuel that performs exactly like 100LL with no problems. They basically want a 100% guarantee that the new fuel will work perfectly with no problems.
I do not believe that a 100% guarantee exists for any new product, no matter how much testing is done.
And a lot of testing has been done.
It’s gotten us to four candidate fuels.
Swift Fuels, which won approval in 2015 to sell its UL94 avgas via the Supplemental Type Certificate (STC) process, is now working with the FAA on a 100% replacement to leaded avgas, called 100R, using a combination of the STC and Piston Aviation Fuels Initiative (PAFI) programs.
According to the patent application, the Swift fuel contains an iron compound, plus other things, to replace the lead. But is that trading a problem we know for a problem we do not know? And past experience was not that good with no good scavenger agents available.
Two other candidate fuels — from LyondellBasell/VP Racing and Phillips 66/Acton — are now going through PAFI testing. Both fuels contain ETBE (Ethyl Tert Butyl Ether), which is an oxygenate with lower energy content and some water problems. There’s also the possibility the fuels will use MMT, a manganese additive that was tried many years ago as a lead supplement. It gave the neatest rust-colored whisker deposit on the spark plugs that was pretty, but fouled out any way.
Now the fourth candidate was sort of the elephant in the room of this presentation that no one wanted to talk about. That is the new G100UL fuel from General Aviation Modifications Inc. (GAMI) that received FAA approval in September 2022. It is approved for almost all aviation engines, but an STC is necessary to use the fuel.
This could be a problem for a large section of the general aviation fleet, as Jack Pelton, chairman of the Experimental Aircraft Association (EAA), pointed out that experimental aircraft cannot use an STC-approved fuel.
The GAMI fuel is a blend of a very high octane alkylate and a second high octane hydrocarbon component. The fuel has passed all the requirements thrown at it and has been in field trials for some time now.
So why does the EAGLE group not get behind the GAMI fuel and push for full approval?
Good question. It appears that they want several approved candidates so it will be a more competitive marketplace.
But the avgas business has always been a single candidate system.
Starting in World War II, the only fuel approved was based on aviation alkylate plus lead. Even when we went to 100/130 low lead, all of the manufacturers used the exact same formula of two grams of lead plus toluene concentrate in aviation alkylate. So why do we need diversity now?
GAMI has offered a license to produce its fuel to anyone who is interested. There does not seem to be any takers yet. I believe the reason is cost. If you look at the components of the GAMI fuel, I feel that the final price will be a little higher than the present 100LL.
By comparison, the cost of the other candidate fuels would be based on the costs of the current aviation alkylate plus a little for the additive, which would be offset by the deletion of the lead additive. This would give it a cost advantage compared to the GAMI fuel. It would also be based on current production streams in the refinery, so no significant capital outlay would be required by the oil companies.
So which way is the GA market going? Are we going for the better product that should have minimum problems in the field? Or are we going to wait another 25 years to find a slightly lower cost fuel that may or may not work?
“This could be a problem for a large section of the general aviation fleet, as Jack Pelton, chairman of the Experimental Aircraft Association (EAA), pointed out that experimental aircraft cannot use an STC-approved fuel.”
I think what is meant is the experimentals don’t need to buy STC’s. That’s different than an aircraft engine not running correctly on a fuel. This is a paper problem, not a fuel problem.
Thankfully, George Braly retracted the statement and acknowledged that ferrocene is not present in any of our Swift Fuels unleaded avgas products. This clarification was made in a public forum today at Oshkosh. In fact, Swift Fuels does not use any metals as octane boosters in any of our fuels. Thanks George.
Chris D’Acosta
CEO – Swift Fuels, LLC
The alphabets now seem to be the biggest roadblock to G100UL
In the very same daily GA News is another story touting Continental flying engines around on Vegetable oil. But nobody can figure out how to distill a reasonable gasoline??? This whole thing smells of government kickback and good ole’ boy politics. Screw the end user.
Although I can’t remember the exact figure, I think the majority of aircraft out there can use lower octane lead free fuel today. Of my 3 airplanes 2 currently fly using auto fuel from the gas station (and what a PITA it is to get to the airplanes because they don’t sell Mogas at my airport). My other airplane could use auto fuel but the gas degrading the composite tank is a concern, but octane is not.
The BIG problem I have with using auto fuel is that Mogas is hard to find at most (or all) airports so when I go on cross country flights I am forced to use 100LL. And then there is the ethanol, vapor lock issues, etc. Let’s face it, auto fuel is not made to go on airplanes.
So I tell the GA organizations fighting this and the FAA: Why should the majority of us care and have to pay more for a 100LL replacement when we don’t need it?
So what I think is the big issue is that if most of us can get and transition to a low octane aviation fuel the economic incentive to create a 100LL will disappear and no one will want to make it. So be it I say. MOST of us don’t need it. Instead of trying to make a fuel that will work with ancient engine technology simply set forth a plan to phase out 100LL and let the market find the best solution. Isn’t that what we believe in here in the USA.
With 94 octane becoming the new aircraft fuel, MOST of us will be able to get a more economical fuel than with a 100LL replacement, progressive engine manufacturers will develop engines that can run it (look at Rotax new 160 hp engine) and Jet-A burning piston engines will become economically feasible (I have worked with both Continental and SMA diesel engines). And want to bet that some companies will even develop STCd modifications for current engines that need high octane to be able to run the low octane aviation fuel?
And for those who still need high octane fuel then they can buy the GAMI fuel available today.
Are we making this harder than it needs to be?
Chris
The reason we don’t have a new fuel is because the top administrators @ EAGLE
have until 2030 to stay on the government gravy train.
Ben Visser’s comments create a gross misrepresentation about Swift Fuels’ unleaded avgas products. None of our unleaded avgas products use metals as an octane booster in our UL94 or 100R — Not Lead, Not Manganese (MMT), Not Ferrocene. George Braly falsely stated on video at Sun n Fun that Swift Fuels was using Ferrocene in our high octane unleaded fuel. False statements about our products mostly reflect on the poor judgement of the source of such false statements. Ben — George —- if you want to know what is in our fuel — please read our ASTM Internationl fuel specifcation — or ask me.
Chris D’Acosta
CEO – Swift Fuels, LLC
What did they do when 100LL replaced red?
We delt with a lot of lead fouling issues. This involved ring flushing, regular reaming of valve guides and the introduction of the “BY” extended nose sparkplug. Dropping 80/87 for 100LL was not with out issues, as some
would like us to believe.
C150s (including mine) have been running happily on non-ethanol 87 octane car gas for DECADES now. No modifications, just the STC and check the idle speed. Higher compression or turbocharged engines would need a few mods and have to give up a bit of HP (which the higher compression gets you) but surely that is easier and less costly than an entire new fuel refining and nationwide distribution system. And what happens if someone flies in from Canada, Mexico or the Caribbean with UNAPPROVED (normal) avgas still in the airplane? Do we have to drain it out and dispose of it at the airport of entry? (Think of the children . . . )
All the associations are begging GAMI to get their fuel ASTM approved. The ball is in their court.
Although I no longer pilot an aircraft due to my age and physical abilities, I have used the Petersen auto fuel STC of the appropriate grade, on Lycoming & Continental engines with no mechanical issues. With all the hype with Swift fuel, Gami & what ever alphabets are attempting to replace 100LL, the prize at the end of the tunnel has disappeared. Bottom line is $$$$, and everyone wants some of it in the form of STC’s. If unleaded E-Free fuel is available & approved for many of the GA aircraft, and is also used without STC approval in experimental’s, those whom are pursuing the replacement for ALL Aircraft should concentrate their effortson the higher compression engines & eventually, their decendants will reap the rewards of a replacement fuel.
I don’t need an STC to burn unleaded mogas in my Experimental because there is no standard type certificate for an experimental aircraft, hence the Special Airworthiness Certificate. While an experimental aircraft may have an approved engine with a Type Certificate, when mounted in an experimental, it can be treated and operated as Experimental as well, though most folks still treat it the same.
Seems to me, as others have noted, there is ROI for fuel companies investment in R&D and establishing manufacturing expenses. Then there is the government involvement. The impenetrable bureaucracy of the FAA coupled with lack of willingness defer to the fuel industry experts knowledge causes gridlock.
Bottoms line is, follow the money and you’ll find the obstacle for industry. Then follow the government bureaucracy and you’ll find some deeply entrench self-serving career bureaucrat who cannot find a way to get their hands on the money.
Oxymoron of the day, “Government Service.”
Spot on! I also built and fly an experimental. Saying we can’t use an STC approved fuel is idiocy.
The best solution is the GAMI solution. It is tested on all engines, available for all airframes and already being rolled out to airports in need. Unlike UL94, GAMI’s fuel can be used on high compression engines as well as low compression engines (UL94 is only a partial solution).
And like others on this forum… huh…? Experimental aircraft can’t use it??? What the heck does that mean?
I assumed the great Visser would state the obvious fuel that has been approved for 30+ years – Mogas. When I visit flying friends in Europe, Mogas is nearly always available at GA airports alongside others, despite weather causing less flying over their annually. When and if I ever own another airplane, it must run on Mogas. Pure-Gas.org shows thousands of gas stations selling ethanol-free mogas around the country, many with the 92-93 AKI required by some engines. Jet-A would be my choice of fuel for a larger engine, especially in developing nations where it and diesel are common. Trying to find a single fuel replacement for all aircraft was a bad idea from the start. Choice is always better, lowering costs and improving quality through alternatives. Go to a Buckees and look at how many different grades and types of fuels are offered at every pump.
>> This could be a problem for a large section of the general aviation fleet, as Jack Pelton, chairman of the Experimental Aircraft Association (EAA), pointed out that experimental aircraft cannot use an STC-approved fuel.<<
Explain this for me, please. Isn’t ethanol-free auto fuel an STC approved fuel?
I remember being in meetings at airshows some 20 years ago where they made you believe that a 100 unleaded fuel was coming very soon, they were confident of that. I am tired of the lies, could we just move on or are we going to be stuck in this time-loop forever. It appears that all the solutions are never going to work and they will be way to expensive and could actually be dangerous. The best of the solutions seems to be UL94. This is really the fuel we know and trust with a little less octane and none of the damaging effects of the lead, which for so many years have actually increased the danger of engine failure. We need to be realistic and start talking about using this fuel, and only this fuel by making modifications to the current piston engine fleet that need higher octane fuel. We already know that it can be done when adding a larger intercooler or just by adding an intercooler on turbo charged engines. In the case of non-turbo charged engines water injection during high power settings will do the job.
I left the aircraft maintenance industry because exposing myself and my family to lead was not worth the pay and abuse. The research is very clear: there is no safe exposure to lead. Maybe the reason why it’s taking so long to get this through is because the people making the decisions have spent too much time inhaling 100″LL” fumes. Forget the environment, don’t you care about your own health?
Eric,
I posted before reading yours, but yours mirrors your sentiment. Add me to the voices that are begging for UL94 to become available at all airports. If we want to keep this argument simple, why would the majority of us have to pay for an expensive 100LL replacement when we can use a simpler, possibly less toxic and cheaper 94 aviation fuel? So that the minority who need (or insists on using) high octane fuel can have it? What is wrong with them using one of the replacements (Swift or GAMI) currently in the pipeline while the rest of us use UL94?
Chris
Experimental can’t use an STC?!?
WT#??
Talk about Kafkaesque Logic.
Certificated Aircraft (usually) require an STC to add an Appliance or accommodate a major change.
Nothing (I know of) says you can’t take something qualified by STC and use it on your Experimental.
Now, perhaps the problem is one can’t mandate an STC for an Experimental. I think the issue is one of semantics and recoupment.
GAMI partially recoups part of their investment by charging for an STC to use their fuel. Maybe they would have to sell an unSTC to the Experimental crowd.