FAA Evaluates 100LL Alternative

Gemini Sparkle

Key Takeaways:

  • Swift Fuel is a proposed lead-free replacement for 100LL avgas, demonstrating higher octane (104.4) and excellent detonation resistance in initial FAA testing.
  • Derived from cellulosic biomass like switchgrass, it offers 13% more heat value and is projected to have a manufactured cost under $2 a gallon.
  • The FAA's tests are preliminary and do not constitute approval; Swift is continuing development and seeking investors for further research and industrial rollout.
See a mistake? Contact us.

Recall last summer that we reported on a new proposed replacement for 100LL that would be both cheaper than avgas and have higher octane. While we don’t yet know about the cheaper part, the FAA’s initial testing has revealed that Swift Fuel has a slightly higher octane than 100LL and has excellent resistance to detonation, something other fuels haven’t been able to achieve without lead as an octane booster. The new fuel contains about 13 percent more heat value than avgas, but it’s also about a pound heavier per gallon. It meets most of the requirements of the ASTM D 910 standard for avgas.

The FAA’s Hughes Technical Center in Atlantic City, N.J., completed technical testing on Swift Fuel in mid-January, reporting an octane value of 104.4. Worth noting is that the tech center’s testing doesn’t constitute industry or FAA approval of the fuel, but is rather a first run at examining the concept.

Swift proposes to make its fuel from cellulosic biomass-switch grass and agricultural waste, for example-for a manufactured price of under $2 a gallon, according to a proposal it presented to an industry research council last year. Although Swift Fuel produces alcohol in its process, the fuel is not ethanol-based but rather combines acetone compounds derived from fermentation of biomass. Swift is continuing its testing through 2009 and seeking investors to fund further research and industrial rollout of the product.

Sign-up for newsletters & special offers!

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

SUBSCRIBE