The aviation sector implementing state-of-the-art engine technologies has made significant progress in reducing the threat of emissions through effective air traffic strategies. Unlike the developments in motor technologies, alternative solutions related to fuels are evaluated in many ways. In order to achieve the objective of emission reduction, thermodynamic performances of low-sulfur diesel and synthetic paraffinic kerosene (SPK), which are preferred as alternative fuel, were investigated. In this study, first, energy and exergy analyses were performed by comparing the fuel consumption of a turboprop engine whilst in a flight period. Energy efficiencies were found lower 6.31% and 7.73% for ultra-low sulfur jet fuels and SPK compared to jet A-1, respectively. At the end of the study, some evaluations about performance effects and improvement processes were made. (C) 2019 Published by Elsevier Ltd.