There have been some developments in the industry’s quest to shift itself away from leaded fuel, i.e., 100LL avgas.
We start in California, where the political push to get the lead out is strongest and has already resulted in prohibiting 100LL at a few airports. In early February, George Braly of General Aviation Modifications, Inc. (GAMI) told online sister publication AVweb.com that his company has an agreement that should result in GAMI’s G100UL unleaded avgas being available on the West Coast by mid-year. The fuel is STC-approved for all FAA-certified spark-ignition engines.
A week later, a California-based group, Center for Environmental Health (CEH), notified all FBOs in the state that they would have to stock G100UL as soon as it becomes available. Implied is that FBOs could stock both fuels, but the practicalities of avgas are that only one likely will be available.
Still focusing on California, state legislation has been offered that would begin phasing in a ban on the sale of 100LL in “disadvantaged communities” and large metropolitan areas as of January 1, 2026, and then to the rest of state by January 1, 2030.
Moving somewhat east and north, the University of North Dakota’s aviation program also in February published details of what it’s calling an episode of valve seat recession among 128 cylinders in its fleet of Piper singles and twins, plus Robinson R44 helicopters. The school had been burning Swift Fuels’ unleaded 94UL avgas in the aircraft’s Lycoming engines. Again according to AVweb, maintenance records show the engines experiencing problems had flown more than 400 hours on 94UL. The school switched back to 100LL and says it is working with Swift Fuel and Lycoming to determine the “specific causes.“
Meanwhile, a Beech C55 Baron with freshly overhauled Continental IO-520 engines and the latest in digital engine monitoring gear is touring the U.S., running one engine on 100LL and the other on GAMI’s G100UL. The project is sponsored by AOPA and GAMI.
Finally, the joint FAA/industry Eliminate Aviation Gasoline Lead Emissions (EAGLE) initiative, whose goal is a universal replacement for 100LL by 2030, has seen one of the fuels under evaluation, from Phillips Petroleum and chemical company Afton, fail a key test. They paused their evaluation, leaving a group led by Swift Fuels as the only other apparent contender.
