Isopropanol as Fuel for Small Unmanned Aircraft

Gasoline engines are increasingly popular for use in small unmanned aircraft requiring endurance due to the specific energy of gasoline (47.3 MJ·kg-1) and its cost effectiveness. However, gasoline is volatile and it poses a health hazard. In this work, isopropanol is proposed and investigated as viable fuel for small gasoline engines. Isooctane is used as a benchmark for performance comparison. The field testing reveals that isopropanol offers similar running performance and ease of starting. The maximum output power of isopropanol is surprisingly found to occur at a more advanced ignition timing compared with isooctane. The significant outcome of this study is that isopropanol can readily be used as a replacement fuel for existing engines without the need for any modifications to the ignition module or the engine itself.