FAA Approves Swift Fuels’ Unleaded Avgas for Over 1,200 Engine Models
In a significant move towards eradicating lead from general aviation fuel, the FAA has substantially broadened its Supplemental Type Certificate (STC) for Swift Fuels’ 100R unleaded avgas. This expansion has added over 1,200 piston engine models and 1,600 airframe models to its Approved Model List (AML). This milestone, declared in mid-July 2026, signifies that approximately 56% of the current U.S. 100LL avgas consumption can now be substituted with the cleaner-burning, lead-free alternative.
The 100R fuel, which complies with the ASTM International specification D8603, is suitable for engines from over 80 manufacturers. These include:
- Lycoming (395 models)
- Continental (195 models)
- Curtiss Wright (95 models)
- Pratt & Whitney (95 models)
Swift Fuels, based in West Lafayette, Indiana, states that this is the first phase of a multi-phase certification rollout. Higher-performance engines and airframes are anticipated to follow in Phase 2 and Phase 3 deployments through early 2028.
Additionally, Swift recently signed a Memorandum of Understanding (MoU) with the FAA Technical Center in Atlantic City, New Jersey. This agreement will test 100R on seven high-performance Continental and Lycoming engines, speeding up the path to full fleet-wide approval. This initiative aligns with the U.S. government’s objective to transition general aviation entirely to unleaded fuel by the end of 2030.
Source: General Aviation News – FAA Approves 100R Unleaded Avgas for More Aircraft