GAMI Gains Avgas STC for Pistons on Unleaded Fuel

The approval comes after the broad and ongoing compliance of the manufacturer’s fuel in aircraft across the fleet.

The distribution of unleaded fuel will be initially driven by industry partners to the EAGLE initiative, such as Avfuel.
[Photo: Julie Boatman]

A milestone in the search for an unleaded fuel replacement for 100LL avgas has been met.

General Aviation Modifications Inc. (GAMI) announced yesterday that its 100-octane unleaded fuel (G100UL) gained FAA supplemental type certificate (STC) approval for use in every general aviation engine using spark-ignition, and each airframe in which those engines are currently operated. This will include higher-compression engines not covered by GAMI’s previous STCs.

The approval comes after the broad and ongoing compliance of the manufacturer's fuel in aircraft across the fleet. While the fuel will continue to be under scrutiny as it enters the supply chain, experts from around GA feel confident that G100UL will meet desired objectives. 

“This is a big day for the industry,” said GAMI co-founder George Braly. “It means that for a lot of our general aviation communities, and especially for a high fraction on the West Coast, relief is on the way. And it means that our industry will be able to go into the future and prosper, and provide the essential infrastructure for this country for everything from Angel Flights to critical training of our future airline pilots.”

In a statement from the General Aviation Manufacturers Association (GAMA), “Manufacturers’ understanding of a new fuel is essential to continued operational safety regulatory responsibilities and business activities such as customer technical support, warranty services and consideration of incorporating the new fuel in manufacturer issued service and approval documents and new production engines and aircraft.”

Industry Hails the Step Forward

Signatories to the industry’s EAGLE (Eliminate Aviation Gasoline Lead Emissions) program expressed satisfaction and enthusiasm for the move forward.

“I’m proud of GAMI, the industry team, and the FAA for persevering over the long term and getting a fuel that the FAA has recognized as a viable alternative to low lead,” said AOPA president Mark Baker. “It’s vital that we find solutions to what has been plaguing general aviation since the seventies. It’s certainly the biggest issue I have dealt with in my time at AOPA.”

“As we continue to work towards a safe and reliable transition to an unleaded future state for piston-engine aircraft, FAA issuance of a broader STC for GAMI’s G100UL is a significant milestone,” said Pete Bunce, president and CEO of GAMA. “Manufacturers look forward to having an opportunity to understand the composition and performance of this new fuel to support commercialization and use as a viable replacement for 100LL.” 

The fleet covered by the STC not only provides a solution for fixed-wing aircraft, but also for the GA piston helicopter fleet. “This is an outstanding first step in protecting our environment and allowing piston-powered helicopters to fly safely and cleanly,” said James Viola, president and CEO of Helicopter Association International (HAI). “Along with the other general aviation associations, we deeply appreciate the efforts of GAMI and the FAA in producing this fuel and STC. As an owner of a piston-powered helicopter, I think I speak for everyone when I say that I can’t wait to fill my tank with this unleaded fuel for the first time.”

A ‘Big Deal’—But More Work To Be Done

The STC process indicates that the FAA has found a wide range of aircraft and engines using the fuel in normal operations that continue to maintain compliance with the airworthiness standards outlined under Part 23 (airplanes) and Part 33 (engines). Avfuel has signed on as an initial distributor and logistics partner, with the invitation open for other partners to participate.

Other fuels remain in play as well, with the understanding that options are critical for the EAGLE program to be fully realized. These include Swift Fuels (which has already received FAA approval for its 94UL (94-octane) unleaded fuel, and is in the process of expanding its distribution, with a focus on the West Coast) and Afton/Phillips66 and Lyondell/VP Racing fuels, as they work through the EAGLE fleet authorization process.

As Baker of AOPA put it: “This is a big deal, but there is a lot of work yet to be done.”

Julie Boatman
Julie BoatmanContributor
Based in Maryland, Boatman is an aviation educator and author. She holds an airline transport pilot certificate with Douglas DC-3 and CE510 (Citation Mustang) type ratings. She's a CFI/CFII since 1993, specializing in advanced aircraft and flight instructor development.

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