As California works to phase out leaded fuel at its airports, the first three tarmacs in the state, all in the Bay Area, started offering 100-octane unleaded fuel last fall.
Contra Costa County officials are also looking at making the switch, joining San Jose, San Carlos and Watsonville. But the challenges that aviation operators are running into in Concord illustrate why the state and federal government’s plan to permanently ground leaded gas by 2031 is not as simple as it might seem.
Take Tanya Ledbetter, COO of Pacific States Aviation, one of two companies that service, maintain and refuel aircraft at Buchanan Field in Concord. The private business offers Jet A fuel, which is lead-free, to corporate birds, as well as the problematic 100-octane, low-leaded fuel that Cessna, Cirrus and other piston-engine planes continue to guzzle.
“I know the community wishes it could go a lot faster — everyone’s anxious for unleaded — but we’re working at the pace that we can,” Ledbetter said. “Unfortunately, that’s just not something that’s drop-in ready for my tank yet.”
Ledbetter said the company’s fleet of small aircraft for its flight academy will “make the full switch to unleaded as soon as we get it,” but other luxury planes using jet fuel to fly in and out of Buchanan Field won’t be impacted by the change.
Investments in new aviation fuels have accelerated since the Environmental Protection Agency released an October 2023 report on the pollution and health hazards tied to leaded fuel. However, many general aviation airports, such as Buchanan Field, are cautious about letting unleaded-fueled planes take off — largely due to uncertainty around aviation fuel, commonly known as Avgas, currently on the market.
The three companies spearheading development — General Aviation Modifications Inc., known as GAMI, Swift Fuels and LyondellBasell/VP Racing — have each achieved approval from the Federal Aviation Administration, but the different regulatory paths they each took have raised red flags from industry leaders.
While GAMI became the first to make its unleaded G100UL fuel available to piston-engine aircraft — unveiled at San Jose’s Reid-Hillview Airport in late October — the company bypassed industry consensus testing, which has since sparked concerns about safety, warranty and supply chains. Manufacturers such as Cirrus Aircraft and Lycoming question whether GAMI’s fuel is safe to be used in their aircraft and engines, warning that it may void their warranties and stir up other legal issues.
Swift Fuels’ unleaded 100R gasoline is still undergoing final industry specification testing, but the company kicked off a restricted rollout in November — starting with the entire fleet of Cessna 172 aircraft at the San Carlos Flight Center.
Swift also produces UL94, a lead-free aviation alternative. However, that form of gasoline can only power about 68% of piston aircraft, highlighting the urgent need for a universally viable 100-octane fuel to achieve the industry’s 2031 goal.
That’s why some operators, including Pacific States Aviation, remain vigilant about potential safety and liability risks of using gasoline, especially formulas that have not yet undergone rigorous industry review and approval.
“This is brand-new fuel, and it’s a brand-new process,” said Greg Baer, who has worked as Contra Costa County’s Director of Airports since May 2022. “My main message is that we all — the industry and the county — want to do this. But taking the time to understand all of these things, with safety being the first priority, is taking a little bit longer than some people would like.”
Baer, a licensed pilot with a background in mechanical engineering, said the industry has been held up by complexities in tech and regulation for decades as it tries to engineer a way to ditch lead, while keeping its properties that prevent engines from pre-detonating and, effectively, blowing up.
Fortunately, Ledbetter said she’s used to this laborious push-and-pull when it comes to aviation regulation, as California is frequently the “example state” to implement new aviation policies, which later see widespread adoption after local officials iron out any kinks.
While Pacific States Aviation will continue to pump 100 low-lead fuel until the ban takes full effect in 2031, Ledbetter’s already preparing for storage tanks, electricity lines and fuel trucks for unleaded fuel — patiently awaiting the green light from county officials to start sourcing and selling greener gasoline.
“From a pilot’s perspective, this should be instantaneous, but from a business perspective, there’s so many logistics that need to get sorted out for us to do this properly,” Ledbetter said. She’s worked to stay educated on an ever-evolving slew of research on unleaded technology, including hours spent scouring forums on Facebook and YouTube videos for feedback from general aviation pilots across the state.
“The community always wants us to be forward with this kind of stuff, and the best thing to do is to keep ourselves educated on the topic and move ahead with safety in mind,” she said. “I’d be lying if I said I’m not just sort of waiting to see if there’s any negative impacts with these products, just to make sure we’re making the right decision.”
Ledbetter applauded ongoing help from Contra Costa County airport staff, which recently outlined a hazy deadline for this regulatory limbo.
Buchanan Field is expected to begin offering unleaded aviation fuel before the end of 2025, according to Baer. He said staff is currently working out logistics to start offering Swift’s UL94 in the coming year.
Ahead of the county’s Aviation Advisory Committee meeting on Jan. 9, Baer said there’s little else the county can do — other than educate future consumers — until the industry comes up with its “100-octane solution.”
“The County is committed to making the transition in a safe and deliberate way,” Baer said. “Nobody wants to have leaded fuel, but we’re waiting on science and chemists to create fuel that can safely operate aircraft.”