Williams International has completed extended testing of alternative fuel in a small gas turbine engine widely used in the general aviation market. An FJ44-3 engine was powered by 2000 gallons of coal-based, alternative fuel for 118 cycles during 21 hours of running at Williams' Walled Lake, MI facility. The synthetic fuel performed extremely well; the engine performance was identical to using Jet-A fuel and required no special engine or test cell modifications for the demonstration. This latest testing validates the flexibility of the robust FJ44 design to take advantage of alternative fuels composed of different compounds and created from various processes.

The fuel was developed by a team at Penn State University with help from Intertek-PARC and Duquesne University. The fuel was created using a coal-based raw feed that was upgraded and then hydrotreated, resulting in a "green" product essentially free of nitrogen, aromatics and sulfur. Sulfur-free fuel yields little to no harmful SOx engine emissions. The fuel has a higher energy density than typical jet fuels, so it can extend aircraft range. The raw feed can also be produced by coal liquification and therefore can be produced, fully home grown, from coal in the United States. This process, which is being developed for coal, could possibly use renewable feedstocks such as waste biomass and municipal solid waste, as well as second generation biomass like algae that does not compete with food sources.

Interest in alternative fuels has increased due to oil price volatility, the desire to reduce greenhouse gas emissions, and the desire for energy independence. Williams International is promoting development and certification of alternative fuels for commercial aviation, and specific plans include emissions and smoke measurement testing and engine testing of other alternative fuels including second generation bio-fuels. Williams International also is participating in the Commercial Aviation Alternative Fuels Initiative (CAAFI), an organization that seeks to enhance energy security and environmental sustainability for aviation through alternative jet fuels.

Williams International is the world leader in the development, manufacture and support of small gas turbine engines. The privately owned company is headquartered in Walled Lake, Michigan. The FJ44 series of engines set a new standard for fuel economy and low emissions for small commercial turbofan engines – every model in the FJ44 series is clean enough to incur no emissions landing surcharges (per Swiss regulations). The FJ44-3 engine powers the Cessna CJ2+ and CJ3 and the Beechcraft Premier II, and is used to re-engine many older aircraft to reduce their fuel consumption and emissions.