To offset the usage of petroleum-based jet-propellant, alternative jet fuels made from sustainable sources are being researched. Due to the Single Fuel Forward Policy, these jet propellant fuels are being used in compression ignition (CI) engines designed to burn ultral-ow-sulfur-diesel (ULSD). In the current study, a single-cylinder CI engine with electronic injection timing burns ULSD, jet propellant (Jet-A), and blends of Jet-A with hydrotreated renewable aviation fuel (R-8). Results for Jet-A and R-8 indicate that injection modulation provides performance that is similar or improved compared to ULSD, particularly when considering fuel consumption. Nitrogen oxides, carbon monoxide, and hydrocarbon emissions are all lower than ULSD for both aviation fuels while yielding similar particulate matter emissions. Results show that re-calibration of engine injection timing in order to account for differing aviation fuels could prove advantageous for military logistics through improved fuel consumption.