Register

Future Fuels

Gemini Sparkle

Key Takeaways:

  • GAMI's G100UL unleaded 100 octane aviation gasoline has received FAA approval, but initial distribution will be limited to California and Washington.
  • Aircraft owners must acquire specific engine and airframe STCs (Supplemental Type Certificates) to use G100UL, a process that requires placarding and mechanic endorsements.
  • Other unleaded fuels, like Swift Fuels' 100R, are also emerging, meaning owners may need multiple STCs to use different fuel types available at various airports.
  • Unleaded fuels are expected to be more expensive than 100LL, especially initially, requiring pilots to factor fuel type, STC compatibility, and price into flight planning.
See a mistake? Contact us.

If somehow you’ve not already heard, General Aviation Modifications, Inc. (GAMI) completed its decade-plus-long effort to earn FAA approval of its G100UL unleaded 100 octane aviation gasoline. But it will be a long time before most of us will see G100UL at our favorite FBO. That’s because GAMI says it’s focusing initial distribution efforts on California and Washington state, where leaded fuel is a particularly salient political issue. Regardless, the time will come when you may have to make some unleaded fuel decisions.

DECISIONS, DECISIONS

The first decision you’ll need to make is whether or when to purchase the G100UL STC. The FAA has approved its use in airplanes, but to exercise that option each owner must acquire rights to use it in the individual aircraft. There are two required STCs, one for compatibility with engines and another showing compatibility with the airframe fuel system. 

Ready to Sell Your Aircraft?

List your airplane on AircraftForSale.com and reach qualified buyers.

List Your Aircraft
AircraftForSale Logo | FLYING Logo
Pilot in aircraft
Sign-up for newsletters & special offers!

Get the latest stories & special offers delivered directly to your inbox.

SUBSCRIBE