Alternative Jet Fuel Shows Reduced Emissions Published Dec. 4, 2006 By Propulsion Directorate AFRL/PR WRIGHT-PATTERSON AIR FORCE BASE, Ohio -- AFRL researchers completed successful engine emissions tests supporting the Department of Defense's Assured Fuels Initiative, an effort to develop secure domestic fuel sources for the military's energy needs. Under the program, researchers demonstrated the operation of a manned Air Force aircraft operating with an alternative fuel. The researchers measured particulate and gaseous emissions from a TF33 PW-103 engine burning JP-8 fuel and a 50/50 blend of JP-8 and Fischer-Tropsch (F-T) synthetic fuel. The F-T process, developed in Germany in the early 1920s, provides a method for producing alternative jet fuels from domestically available hydrocarbon products such as natural gas, coal, and shale. The TF33 engine emissions testing occurred at Tinker Air Force Base, Oklahoma, using AFRL's Turbine Engine Research Transportable Emissions Laboratory (TERTEL). TERTEL is a 16 x 8 ft trailer equipped with state-of-the-art instrumentation for the measurement and analysis of turbine engine emissions. The research team measured emissions over a wide range of engine power conditions, from idle to maximum power. For all engine conditions, results indicated that compared to the JP-8 fuel, the F-T fuel blend yields significant reductions in particulate emissions. Specifically, the team observed a ~20%-40% reduction in particle concentration and smoke number and a ~30%‑60% reduction in particulate mass. Furthermore, the F-T blend appeared to have negligible effects on most gaseous combustion products, suggesting that it had no adverse effects on the TF33 engine emissions.