100LL Replacement Talks Held-Issues Remain

The developer of the only available unleaded replacement for 100LL says he met with an industry committee charged with smoothing the transition to an unleaded future for the first time last week. George Braly, whose G100UL is available by STC for all gasoline aircraft piston engines, said he met with members of the Eliminate Aviation Gasoline Lead Emissions (EAGLE) task force, which was formed 18 months ago. He told AVweb at a forum held Monday at AirVenture 2023 on the unleaded fuel situation that he offered solutions to issues raised about the accessibility of G100UL, especially for non-certified aircraft.

Braly and Swift Fuels have chosen the STC route for making the replacement gas legal to use in GA aircraft, while Afton Chemical/Phillips 66 and Lyondell Basell/VP Racing are attempting to get a "fleet authorization" for their fuels through the FAA's Piston Aviation Fuels Initiative program that will also eventually lead to approval by the standards organization ASTM. EAA Chairman Jack Pelton has repeatedly noted the STC process is unavailable to those who fly experimentals and warbirds because they are uncertified and ineligible for STCs.

Although the unleaded fuel is documented as safe for the engines, builders and restorers must ensure it is safe for the tanks, seals and other parts of the fuel system. Information needed to establish that compatibility is closely held by Braly for G100UL, and Pelton maintains that homebuilders cannot fully determine the suitability of the fuel for their aircraft. The two companies seeking fleet authority have to disclose their formulas to get certification and the data will be publicly available.

Braly said he offered to show the group how that compliance can be achieved by any builder without him releasing trade secrets but they haven't taken him up on that. He's also adamant that he will not reveal those secrets because he doesn't trust the ASTM process or its players. He said his fuel has been widely tested and shown safe and he's now working on distribution networks to get it to airports. Braly also alleged that some unnamed leaders of aviation groups have actively worked against his effort to get the fuel universally accepted.

EAGLE has set 2030 as the year that leaded avgas is eliminated entirely and committee member Lirio Liu, who heads the FAA's certification department, said there is a lot riding on getting it done. "[The world] is looking to the U.S. to solve this problem," she said.