The Federal Aviation Administration has published its final transition plan to move U.S. piston aviation away from 100LL leaded avgas and toward unleaded replacements. The four-phase roadmap covers fuel approvals, testing and fleet transition steps, with the agency targeting an end to leaded avgas use by 2030 outside Alaska and by 2032 in Alaska.
The plan centres on three candidate high-octane unleaded fuels: GAMI G100UL, Swift Fuels 100R and LyondellBasell/VP Racing UL100. Phase 1, focused on approval and comparison testing, is due to finish in spring 2027, after which the FAA plans to update the roadmap in late 2027. The agency is also preparing a public FAQ and a summary of comments on the draft version released in January.
The transition sits within the broader EAGLE initiative and follows a requirement in the 2024 FAA Reauthorization Act. 100LL will remain available during the changeover, and federally obligated airports that offered it in 2022 are generally required to continue supplying it until replacement conditions are met or statutory deadlines take effect. Aircraft operators will need at least a new fuel placard, revised operating information and a logbook entry before using an approved alternative fuel.