The transition to unleaded (G100UL) is gaining traction, but distribution is the primary bottleneck. The Good: G100UL is STC'd for almost every piston engine and mixes safely with 100LL in your tanks. Current Locations: As of early 2026, availability is centered around early adopters: California: Reid-Hillview (KRHV) in San Jose (the first to ban 100LL) and Watsonville (KWVI). Mississippi: Tupelo Regional (KTUP). Note: Many other airports (like Santa Monica) offer Swift UL94, but that is not safe for high-performance engines like G100UL is. The Bad: Rollout is slow because FBOs require expensive new infrastructure (separate tanks and trucks) to carry a second fuel type.