Small turboprop engines continue to play a fundamental role in regional aviation, training aircraft, and utility missions, where efficiency, reliability, and operational flexibility are key requirements. The increasing availability of computational tools has made performance models an attractive solution for the analysis and preliminary design of propulsion systems, enabling accurate performance predictions with limited computational cost. The objective of this thesis is the development of a physics-based numerical model capable of simulating the steady-state performance of a 1000hp class turboprop engine under different operating and environmental conditions. The model is based on a zero-dimensional thermodynamic representation of the engine and includes the main propulsion system components, such as the intake, compressor, combustion chamber, turbine stages, exhaust nozzle, and propeller load.