The presentation will focus on the properties and performance of UL100E, a new 100-octane unleaded fuel for piston aircraft. UL100E is the only remaining candidate fuel in the FAA PAFI program. Lyondell and VP Racing Fuels jointly developed the fuel and successfully balloted an ASTM test fuel specification for UL100E (ASTM D8631). The presentation will also provide an update on the testing that includes comprehensive materials, engine, and flight testing. Session type: Forum — Skyfarer is not affiliated with the Experimental Aircraft Association (EAA) or EAA AirVenture Oshkosh. This session is listed for informational purposes from the official AirVenture 2026 schedule. Times and locations can change during the event — verify on the official session page: https://events.rdmobile.com/Sessions/Details/3540987