The FAA on Thursday granted supplemental type certificates for the use of the General Aviation Modifications Inc. (GAMI) G100UL high-octane unleaded fuel throughout the piston-powered aircraft fleet. Deputy FAA Administrator Bradley Mims called the action a “major step toward supporting the safe replacement of leaded gas.”
Under the broad approval, the agency is requiring GAMI to work with aircraft owners to track and report any mechanical issues that may arise from use of the fuel, as well as to track fuel deliveries to airports across the nation. The move followed a review by an independent technical panel that evaluated GAMI’s test results and other documentation, the FAA said, adding it plans to use the same process for other potential unleaded fuel candidates as they near readiness for the market.
GAMI first obtained a supplemental type certificate in July 2021 for use of the high-octane unleaded gas, initially for the Lycoming engines that power some Cessna 172s, and has since worked to expand the approved model list to cover the fleet of spark-ignition piston-powered aircraft and engines.
“This is a big day for the industry. 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,” said GAMI co-founder George Braly. ”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.”
General aviation groups, which have coalesced under a government-industry Eagle initiative to step up the urgency in bringing an unleaded fuel to the market, lauded the FAA fleet approval for the GAMI fuel.
General Aviation Manufacturers Association president Pete Bunce called the expanded approval for GAMI’s G100UL a significant milestone and said, “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,” he said. This understanding will pave the way for manufacturers to provide customer technical support, warranty services, and service and approval documents.
“This is a big deal,” said Aircraft Owners and Pilots Association (AOPA) president Mark Baker. “It’s vital that we find solutions to what has been plaguing general aviation since the 1970s. It’s certainly the biggest issue I have dealt with in my time at AOPA.”
The FAA approval of GAMI’s G100UL for the piston fleet brings the industry closer to an unleaded avgas future, industry leaders say.
However, Baker added that “there is a lot of work yet to be done.” The timing for the delivery of G100UL remains uncertain. Avfuel is standing by to help manage logistics and distribution, according to Braly, who added he is open to other partnerships.
“Our arrangement is that any qualified refiner or blender of existing aviation fuels will be eligible to produce and sell it subject to the quality assurance requirements that the FAA has approved,” he said. “It’s going to take a while to manage the infrastructure including manufacturing and distribution.”
Braly called existing infrastructure “very wounded” and said that was not going to make the process easier. But “we have a handle to do this,” he said, noting distribution will be limited initially with a rapid ramp-up anticipated after that.
The National Air Transportation Association estimated that the fuel would be widely available in the 2024 timeframe. Newly appointed NATA president and CEO Curt Castagna was equally enthusiastic about the approval, saying the association “is pleased to see this advancement toward an unleaded Avgas future take shape”
He added that as G100UL becomes commercially available over the next few years, ”we look forward to continuing to develop infrastructure support, resources and training for airports, FBOs, and other refueling operators, as well as guidance on unleaded avgas conversion considerations now for fuel service providers to support its safe and effective rollout.”
Cost is still not determined but is expected to be slightly more than avgas. “Until we can get [production] revved up that we’re making millions of gallons at a time, there will be an incremental [additional] cost,” he said. “It’s not going to be unreasonable.”
Braly, however, said owners should see their engines operate more efficiently. “I think the days of cleaning spark plugs every 50 hours are going to be behind us for good.”
California markets should receive the fuel as soon as possible, Baker said, noting some municipalities have already banned the sale of leaded avgas. “It is a politically-charged issue there, and this will help keep our airports open with fuel that works with all aircraft.”
In addition to GAMI, Swift Fuels had received FAA approval for 94-octane unleaded fuel several years ago and has expanded distribution, particularly on the West Coast, AOPA noted. Swift further is working on 100R unleaded fuel that will have more than 10 percent renewable content.
AOPA said two other high-octance unleaded fuel candidates—Afton/Phillips66 and Lyondell/VP-Racing—also are in testing.
Other general aviation organizations weighed in as well. Helicopter Association International president and CEO James Viola called the approval an “outstanding first step” while Experimental Aircraft Association chairman and CEO Jack Pelton said: “This is a significant accomplishment that opens the door to the hard work that remains to create a commercial pathway and acceptance across the broad spectrum of the general aviation fleet.”
The expansion of unleaded fuel availability is critical, according to the general aviation leaders. Not only are certain communities beginning to ban leaded fuel, but the Environmental Protection Agency is planning to issue an endangerment finding for leaded avgas as early as next year, setting the stage for a nationwide ban on 100LL. Meanwhile, European regulators and certain communities in the U.S. are already attempting to move forward on such bans.