The FAA has issued an STC for Swift Fuels 100R unleaded avgas to be used in Cessna 172R/S Skyhawks with Lycoming IO-360-L2A engines. Those are the only aircraft configurations covered by the STC but Swift says that’s only the beginning. The breakthrough was first reported by Aviation News.
Swift Fuels is managing a comprehensive program targeting the global replacement for 100LL within 3 to 5 years, said Swift CEO Chris d’Acosta. “Our 100R unleaded avgas product will be the preferred fuel to eliminate toxic lead from avgas. We are actively working with industry and OEMs on FAA-certifications and ASTM International specifications. Yes, the FAA recently approved a critical part of our engine and airframe (STC) certification program. This follows a similar FAA / ASTM approval pattern we architected for UL94 avgas over 9 years ago.
The 172s captured by the STC are the newest in the fleet. The R model was launched in 1996 as the first fuel-injected model. It was produced through 2012 and the engine was limited to 2400 RPM and produced 160 horsepower. The S model has the same engine, but its RPM limit is 2600 RPM and it’s rated at 180 horsepower.
According to Lycoming’s Service Instruction, specifying approved fuels, that engine is the most flexible when it comes to what makes it go. In addition to 100LL and other 100 octane leaded aviation fuels, it can use 91 and 94UL aviation fuels and 93 AKI mogas. D’Acosta did not say what engine and airframe combinations might be next.
