Swift Enterprises, an Indiana start-up, is pursuing a replacement for 100LL in aviation fuels using biologically derived products. The company claims that the product, 100SF will meet or exceed the current standard for low lead AvGas, ASTM D 910. Swift, based at the Purdue University’s Research Park, was started in 2001 for the development of sustainable fuel for use in aviation, as well as developing cheaper fuel cells for use in electric cars.
The intention is a truly replacement gasoline, with no modifications or alterations necessary for current aviation piston powerplants. Tests have been conducted in a number of engines, both statically as well as in flying test aircraft to demonstrate viability. The flight tests have included Van’s RV-3 and RV-4 as well as a Beechcraft Bonanza G36. According to the company, the tests have been encouraging and may allow them to begin manufacturing the new fuel in Q3 2011.
Comparisons between 100LL and 100SF indicate that the Swift derived fuel is advantageous to 100LL in energy density and MON, the octane benchmark used in testing various fuels. The main barrier to a replacement fuel, detonation, also has appeared to have been addressed.
The total consumption of AvGas currently is approximately 300 million gallons annually. Swift Enterprises calculates that to maintain that production annually, 400 square miles of sorghum, the crop of choice, are needed to be planted annually. This constitutes the land mass of around .010% of the landmass of the USA. For comparison, in 2007, the total land area used in farming was 40.1%