The FAA has expanded Swift Fuels 100R Unleaded Avgas Approved Model List (AML), adding 1,200 piston engine models and 1,600 airframe models to the original 100R Supplemental Type Certificate, which was first approved in September 2024.
The new certifications, orchestrated by the FAA’s Central Certification Branch, cover a wide swath of piston aircraft engines and airframes now approved via STC for the use of Swift Fuels 100R unleaded avgas — all of which comply with ASTM International fuel specification D8603, according to Swift Fuels officials.
They add this includes STCs for more than 1,200 piston engine models from more than 80 manufacturers, including Lycoming (395 models), Continental (195 models), Curtiss Wright (95 models), Pratt & Whitney (95 models) and many more.
The approvals also include STCs for more than 1,600 airframe models from many manufacturers, including Textron Aviation (118 Cessna models and 101 Beechcraft models), Piper (98 models), Grumman, WACO, Fairchild, Mooney, Stinson, and more, company officials said.
The official listing will appear soon on the FAA’s Dynamic Regulatory System (DRS). The latest approved list can be seen here.
With the new approvals, Swift Fuels is expanding its commercial availability across the country and around the world, company officials noted.
Aircraft owners must purchase an STC to use 100R avgas. Swift Fuels Forever STCs can be purchased at SwiftFuelsAvgas.com.
Aircraft owners who have already purchased a UL94 STC from Swift Fuels will automatically receive a 100R STC at no extra charge as part of the company’s Forever STC program, company officials added.
Company officials note that the recent approvals represent Phase 1 of Swift Fuels’ unleaded avgas transition plan.
“These Phase I approved engines and airframes represent certificated aircraft that routinely consume up to 56% of the 100LL avgas across the US,” they said. “We anticipate the balance of the higher performance engines and airframe combinations to be added to our 100R STC/AML in Phase II and Phase III deployments, expected during 2026, 2027, and early 2028.”
The company noted it has accelerated its engine testing program by working with FAA fuel testing experts at the William J. Hughes Technical Center in Atlantic City, New Jersey. This gives the company access to seven high-performance engines managed by the Tech Center. The ultimate aim is to achieve a fleetwide approval for 100R.
The engines in the FAA testing program include:
- Continental IO-550D
- Continental TSIO-520-VB
- Continental O-470-U
- Continental W670-6N
- Lycoming IO-540-K1A5
- Lycoming TIO-540-J2B
- Lycoming TIO-540-AJ1A.
Meanwhile, in the coming weeks, many airfields, flight schools, and private users whose aircraft have utilized Swift’s UL94 unleaded avgas for many years will begin their transition to 100R unleaded avgas, while other airfields have chosen to start fresh with 100R, Swift Fuels officials said.
These airfields are located across 29 states, including California, Colorado, Utah, Minnesota, Arizona, Florida, Wisconsin, and more. In addition, the fuel has been approved for use at airports in Canada, Germany, France, Austria, UK, the Netherlands, and Australia.
The company has released a map that highlights airports that sell Swift unleaded avgas here.
Swift Fuels expects to have the initial Phase I transition from UL94 to 100R completed in about one to two months, starting this summer.
For more information: SwiftFuelsAvgas.com
When will the turbo charged engine’d airplanes receive approval for the 100R fuel? I’ve stated it before, in turbo engines, upper cylinder lubricating is very crucial to cylinder life. Besides detonation reduction, the lubing action of lead in 100LL helps tremendously there during high power operations as the oil itself is not enough to lube this area sufficiently. The thin film of oil that makes it up there gets mostly burnt off or washed away during the combustion process as a result leaving the compression rings mainly without sufficient lubrication. Lower powered engines do not see or realize this crucial area during operation as the combustion process has far less heat and flame front. Will there be some type of lubing action agent in this 100R through another product that is fabricated into the gasoline or will an owner/operator need to add something to his tanks above during refueling? These and other questions will be oncoming as 100LL is phased out.
My engine just talked and one of of the first questions my engine builder asked was if I had ever run Swift fuel in it. I had not, and based on their experience, I will never run that stuff!
How many people have died from the old fuel with lead?
The amount of lead in aircraft fuel seems minimal?
All the people, pilots, maintenance personnel, fuel pumpers that are around the flight line have died from lead poisoning??
The EPA say there was a drop of probably 7 IQ points do to the lead ingestion in the baby boomer generation that from Lead ingestion they encountered in their lifetime. It appeared it only made them stupid, but didn’t kill him.
Denying science seems to be an obvious side effect 🙂
On a serious note, and as I have said in the past, I still have not heard anything yet from Lycoming in terms of engine designs that can run on unleaded fuels. And the air-cooled vs water cooled debacle is just an excuse. Look at the ULPower UL520T engine (220 HP). What about all the of piston diesel engine designs out there? I had a chance to work with the Continental and SMA diesels and they are neat alternatives. If these technologies were embraced they would advance quickly and become mainstream solutions. And the whole certification excuse, I worked my entire life in a highly regulated industry where certifying our products was what was done day in and out. A pain, sure, but doable.
If people stopped buying overpriced, antiquated engines that, are inevitably on their way to extension, and supported new technologies moving forward we would once and for all move into a more sustainable future. Boutique fuels are only a stop gap solution that will quickly become unpopular once the cost and complexity of implementation becomes obvious.
Me, my three airplanes run happily on auto fuel (Lycoming and Rotax). The big problem I have is finding good clean Mogas at airports these days. I wish UL94 was more readily (and affordably) available.
Yup, I agree with Erok on his assessment about the consequence of lead in our generation 🙂
Chris
I don’t believe anything the EPA says!! They have just screwed up all my diesel fuel vehicles! They passed a bill to refine all the diesel fuel to remove all the sulfur. This is reason diesel fuel is so high priced and causes all products you purchase to be more expensive from food and everything you purchase!. The retailers just transfer the delivery cost to the consumer!!
I’m 83 years old and been a mechanic from aircraft to my ranch equipment..
40 plus years working in the military…😩😩😡
I’ll take a stupid baby boomer over an arrogant smart aleck any day of the week.
Will there be an FAA ‘manual’ or ‘AC’ published for ultralite[2 & 4 stroke engines], homebuilt with uncertificated engines, antique aircraft with radials and water cooled engines, etc… for conversion-to/long-term use of this fuel… and the following…
engine types currently approved?
compatible mateials? plastics rubbers, metals, etc…
altitude and temperature use conditions.
long-term inactive parking with this fuel [fuel degradation, mateials degradation, etc] and…
storage, handling?
Etc…
You may not have to worry about using 100R in an aircraft that can not acquire an STC. I asked the Fueler at Reid Hill View Airport if they would put their 100 G in any aircraft that asked for it, I was told no, they would have to see an STC before they could fuel the airplane.
In other words, “DON’T FEED THE FBO FINANCIER — CONTINUE TRUCKING YOUR OWN GAS TO THE AIRPORT. CONTINUE SUPPORTING OFF-AIRPORT SUPPLIERS!”
Why would an STC be required to use a different formulated fuel for a aircraft when there is no required modification to said aircraft to use that fuel. I remember through the years I have been offered many different new types and brands of oils and they never required me to get an STC. I think it might come down to the FAA which seems like a very incompetent government agency.
In the FAAs eyes the safest airplane is one that never leaves the ground
The STC modifies the limitations section of the AFM that only allows the use of certain fuels, and enables the use of a new fuel. The STC cost is how the new fuel developer recoup some investment, but by selling you the STC it ensures they understand who is using their fuel, on what aircraft/engine combination, and ensures that they know who to notify in the event of any future service bulletin or AD related to the use of the fuel.
So I looked at my AFM and it says use Aviation grade; 80/87 minimum grade. So nothing there limited the use of Aviation grade 100R.
A mo gas STC only allows 5% ethanol in the fuel……..any more negates the STC…
UL100 has been coming out for years….????
FAA moves with the speed of dried mud up hill
My mogas STC states ‘NO ETHANOL’ on the placard near the tank filler, which means zero .’0′.
What will the average price for this boutique fuel? We know the price of the most important lead-free aviation fuel on the planet – Mogas. See Gas Buddy and Pure-Gas.org for thousands of sellers at prices well below $3/gallon, heading to sub-$2.00.
I use Gasbuddy every day on my road trips, and non ethanol on Pure-Gas .org is always more expensive than ethonal fuels. Where do you see “thousands of sellers at prices well below $3/gallon” ?