Adoption of hydro-processed esters and fatty acid biojet fuels is a critical component for the sustainability of the aviation industry. Aviation biofuels reduce pollution and provide alternatives to conventional fossil fuels. A study of the impacts of biofuels on emissions from a T56 turbo-prop engine was undertaken as a joint effort among several departments of the Government of Canada. In this study, particulate (including particle number and black carbon (BC) mass) and regulated gaseous emissions (CO2, CO, NO, NO2, THC) were characterized with the engine operating on conventional F-34 jet fuel and jet fuel blended with camelina-based hydro-processed biojet fuel (C-HEFA) by 50% in volume. Emissions characterization, conducted after 20-hour ground engine durability tests, showed immediate significant reductions in particle number and BC mass when the engine was operated on the C-HEFA blend. Operating at high speed ground idle (HSGI) using the C-HEFA blend reduced particle number and BC mass emissions by 31% and 50%, respectively. At Take-off engine mode, particle number and BC mass reductions were 22% and 32%, respectively. In addition, particles generated from the C-HEFA blend were also observed to be slightly smaller than those generated from the conventional jet fuel by 2-4 nanometer (nm). CO emissions from the C-HEFA blend were lower by 4-6%. CO2 emissions from the C-HEFA blend were lower by approximately 1%, consistent with the difference in hydrocarbon ratios in the C-HEFA blend.