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 biomassswitch grass and agricultural waste, for examplefor 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.