The paper describes the basic components and the principle of operation of a turboprop engine of the C-130 Hercules aircraft. The paper also includes an extensive analysis of the aircraft flight profile (departing from the Powidz airfield, Poland to Bagram Afghanistan). Following the flight log, the paper contains many calculations, to show the influence of the changing meteorological conditions on the aircraft performance, particularly temperature, altitude and ambient pressure. The results of the investigation constitute the foundations to create further steps of the research for the optimization of a flight profile that balances the amount of fuel and mass of the cargo. Finally, the authors suggest a development of specific software to simulate a flight prior to departure, based upon available data before the mission.