In transition
AOPA’s transparent and factual position on 100LLAOPA’s transparent and factual position on 100LL
The FAA Reauthorization Act of 2024 supports the continued availability of 100LL avgas until the end of 2030, or when a certified unleaded alternative is available at airports. (Alaska, a state heavily reliant on piston-engine aircraft, has been given an extended timeline protecting continued availability of 100LL through the end of 2032.) Given the importance of this transition to our industry and hearing of some confusion among pilots, I assure you that I firmly believe in not only the importance of getting to an unleaded avgas future, but also the need to be both transparent and factual as we navigate this important journey. AOPA’s position on this journey is clear:
First, AOPA does not support one unleaded fuel over another. The marketplace (pilots) will ultimately determine which fuels are successful and which are not.We owe it to the entire industry to quickly assess issues as they arise and respond accordingly as we learn.
Second, AOPA is a strong proponent of a “burn and learn” approach to newly authorized unleaded fuels to help accelerate a transition to an unleaded future. As we did with a dual-fuel Beechcraft Baron last year (see “Unleaded Fuel: What We’ve Learned,” November 2024 AOPA Pilot), AOPA will continue to demonstrate new unleaded fuels as they become available, and we’ll provide full transparency on our results. Our experience with General Aviation Modifications Inc.’s G100UL has been widely reported and was positive overall. Swift Fuels’ 100R has been authorized by the FAA for use in Cessna 172R/S airplanes with Lycoming IO-360-L2A engines. As more aircraft are added to the approved model list, we’ll be demonstrating 100R and will share our experience with the industry. Lyondell/VP has also submitted a fuel to Piston Aviation Fuels Initiative for testing, and we’ll look forward to the opportunity to demonstrate that fuel as well once it’s approved by the FAA.
Third, a key tenet of the “burn and learn” approach is a rapid and transparent assessment by both the FAA and fuel producers to quickly determine if any reported concerns about using 100-octane unleaded avgas are in fact a result of using the new fuel, and if there are mitigation options that should be shared with other users. We owe it to the entire industry to quickly assess issues as they arise and respond accordingly as we learn. AOPA will also continue to partner with all key stakeholders across the aviation ecosystem to advocate for open and transparent materials compatibility testing throughout the supply chain.
This challenge is somewhat amplified for the homebuilt community because of the diversity of materials used, placing an extra burden on experimental aircraft operators to make these assessments themselves. The Experimental Aircraft Association is working on guidance to help owners of these aircraft navigate this journey effectively.
While the GA industry works toward a transition to unleaded avgas by 2030, aircraft must be able to rely on leaded avgas at least until an unleaded alternative is available at airports across the country. In Colorado, opposition from AOPA and others successfully removed legislative language banning leaded avgas. GA supporters in Washington state defeated a bill that would have imposed myriad unfunded mandates on the state aviation division to address lead in fuels. AOPA co-led the effort with the Washington State Aviation Alliance by urging legislators to partner with the aviation community toward the common goal of removing lead from avgas in a safe, smart manner. And in California, AOPA led an aviation industry coalition to drastically amend California legislation seeking to ban the sale of 100LL at airports beginning in 2026. New language now aligns any fuel sale prohibition with the FAA Reauthorization Act of 2024.
At AOPA, we’ll tirelessly advocate on behalf of all our members—and the general aviation industry more broadly—for a transparent approach to getting safely to the unleaded future we’re all committed to.
If you’ve used 100-octane unleaded avgas in your airplane, I encourage you to share your experience—good or bad—with me online (aopa.org/unleadedavgasexperience). 
