Industry, FAA partners tell Alaska committee transition from leaded avgas is complex and supply-dependent

Industry and federal partners briefed the Alaska House Transportation Committee on March 13 about national efforts to replace leaded aviation gasoline and the challenges that make Alaska’s transition particularly complex, including supply-chain limits, testing standards and the need for industry consensus standards.

Kurt Castagna, president of the National Air Transportation Association (NATA) and co-chair of the EGLE (Eliminate Aviation Gasoline Lead Emissions) initiative, told the committee the EPA’s endangerment finding and the FAA reauthorization created a pathway toward unleaded fuels but did not ban leaded gasoline. "It did not ban the fuel. It did not ban the sale of fuel. It did not ban the refinement of the fuel," Castagna said, summarizing the recent federal determinations.

Castagna and Karen Huggard, vice president for legislative and government affairs for NATA, described two parallel technical pathways industry is using to field unleaded replacements: supplemental type certificates (STC) for specific aircraft and a broader Piston Aviation Fuels Initiative (PAFI) testing pathway that aims to produce an industry consensus specification (typically an ASTM standard). They warned that a fuel developed outside an ASTM consensus process can be hard for distributors and airports to accept.

The presenters detailed supply risks and Alaska-specific logistics. Castagna told the committee the tetraethyl lead additive used to blend 100LL (100 low lead) is made at a single source in Liverpool, England and that the supplier has signaled a business decision to wind down production. He said refining capacity and refinery equipment (distillation towers) in California and elsewhere may not be configured today to produce the higher-alkylate bases that some candidate unleaded fuels require.

Castagna offered data on national and Alaskan fuel volumes and infrastructure to underscore the supply issue: in 2023, the U.S. sold about 176 million gallons of avgas; Alaska accounted for a disproportionately high per-capita consumption, and the presenters estimated the state has about 68 fixed-base operators (FBOs), 6,400 pilots, roughly 8,100 aircraft and about 3,300 mechanics. "You have the highest per capita consumption of Avgas in the nation by a long shot," Huggard said.

Two candidate fuels are at the center of current debate. One developer (GAMI/GAMMI in testimony) pursued STC approvals without pursuing an ASTM consensus standard; another producer, Swift Fuels, has pursued ASTM and offers a UL94 product that the presenters said can serve about 80% of the piston fleet, and is testing a broader 100R product intended to reach a larger share of engines. Castagna and Huggard said industry preference and distributor practice heavily favor fuels with ASTM consensus specifications because those standards provide transparent, peer-reviewed test methods and material-compatibility data across the supply chain.

The presenters described the regulatory and marketplace consequences for Alaska. The FAA reauthorization includes grant-assurance language protecting federally obligated airports’ access to 100LL until a federally approved, industry-standard replacement becomes available; presenters said that language prevents federally obligated airports from removing access to 100LL before a broader authorization exists. Huggard said the ASTM process and PAFI testing provide that marketplace transparency; fuels that bypass that process can face commercial resistance and potential legal challenges at the state level.

Committee members asked about cold-weather performance, barge and storage logistics, and incentives. Castagna said the PAFI and STC test programs include low-temperature and material-compatibility testing but noted that proprietary STC submissions are not always fully visible to third parties; ASTM transparency is designed to address that. For Alaska, the department and industry discussed possible interim approaches such as limited test shipments to evaluate performance in subzero conditions and airport-level incentives, including flowage-fee credits or tax credits that some airports or policymakers might consider to ease price differences for early adopters.

The presenters emphasized the need to avoid an uncoordinated rollout that could strand high-performance engines that rely on lead for detonation protection. Castagna said some engines may require additional modifications such as electronic ignition or other changes to remain operable on new fuels; industry and FAA work aims to identify remedies to prevent "orphaned" engines.

Ending: Castagna and Huggard said they visited Alaska in recent weeks, toured Alaskan fuel infrastructure and intend to continue working with the state’s carriers, distributors and congressional delegation to protect fuel access during the transition. The committee received the briefing and did not take formal action.