OSHKOSH, Wisc.—In July, over 10,000 general aviation aircraft gathered at the Experimental Aircraft Association’s AirVenture, the world’s largest aviation event.
Aircraft owners shared a common concern: the potential phase-out of the leaded fuel their planes rely on.
General aviation remains the primary user of leaded transportation fuel in the U.S. While lead was removed from automotive gasoline in the 1970s due to health risks, aviation fuels like 100LL (100-octane low-lead) remained leaded for high-octane needs.
The Federal Aviation Administration reports that over 220,000 aircraft still use aviation gas, excluding most commercial airliners that use kerosene-based jet fuel.
Lead exposure can impact brain, nervous system, and reproductive health, as noted by the Environmental Protection Agency. Jay Turner, a Washington University researcher, highlighted health risks of lead from aviation emissions.
The FAA and industry groups launched the EAGLE initiative in 2022 to eliminate leaded aviation gasoline by 2030. The FAA Reauthorization Act of 2024 supports this goal.
A 2030 Target, but Challenges Remain
At AirVenture 2026, the FAA introduced a four-phase transition plan. Currently in phase one, the plan aims for high-octane unleaded fuels to replace 100LL by 2027, but no alternatives have been widely adopted yet.
Jack Pelton of the Experimental Aircraft Association expressed doubt about meeting the 2030 goal. The FAA Reauthorization Act describes this transition as necessary but acknowledges challenges.
One-Fuel Solution
Swift Fuels claims its UL94 unleaded fuel suits about 70% of U.S. piston-engine aircraft, but not high-performance models. Although 100 airports offer unleaded fuel, many aircraft still use 100LL due to economic barriers.
Swift Fuels is developing the 100R fuel to replace 100LL, indicating a commitment to the 2030 deadline.
Alternatives like G100UL by GAMI and UL100E by VP Racing Fuels are in varying stages of approval. G100UL is approved for most piston-engine aircraft, while UL100E awaits further testing.
Concerns From California
Santa Clara County in California stopped selling 100LL in 2022 due to health concerns. The FAA opposed this, but the county has maintained its stance. Airports in the area offer UL94 and began selling G100UL in 2024.
Michael Luvara, a pilot, highlighted potential risks with unleaded fuel at AirVenture. GAMI’s George Braly investigated issues, attributing most to pre-existing leaks with 100LL.
Swift Fuels recently expanded FAA approval for their products to more aircraft models and continues to develop alternatives.
The aging U.S. aviation fleet complicates fuel transitions, as parts and modifications are costly and complex. Despite challenges, the industry aims to reduce reliance on leaded fuel by 2030.
Swift Fuels projects 100R will replace 95% of 100LL by 2030, while GAMI is scaling up production. FAA’s Paul Wrzesinski estimates a new fuel could take up to 24 months to distribute nationwide.
Pelton indicated that nationwide distribution of approved fuels remains a significant hurdle.
Original Story at insideclimatenews.org