NATA congratulates LyondellBasell and VP Racing on an important milestone marked by the publication of ASTM D8631-25, the Standard Specification for Unleaded Aviation Gasoline Test Fuel Containing Ethers. Issued by ASTM International in November, the standard establishes the first ASTM specification for UL100E, the unleaded aviation gasoline co-developed by LyondellBasell and VP Racing. UL100E is currently undergoing evaluation by the FAA, in coordination with aircraft and engine manufacturers, through the Agency’s Piston Aviation Fuels Initiative (PAFI), with completion of testing anticipated by September 2026.
“The publication of ASTM D8631-25 reflects meaningful progress for UL100E and the broader effort toward a commercially viable unleaded aviation fuel, affirming the extensive technical work led by LyondellBasell and its partners,” said NATA President and CEO Curt Castagna. “An ASTM standard specification is a prerequisite for a fuel to advance through evaluation and consideration under the FAA’s Piston Aviation Fuels Initiative. As progress toward an unleaded aviation future continues, NATA reaffirms its support for clear, structured, ASTM-based processes that advance innovation while reinforcing safety and operational certainty.”