The last process of the whole overhauling process of an aeronautical engine is the test of its performance. From the information acquired in tests carried out in the test cell, one can know the actual state of the motor and identify possible maintenance needs of one or more components. In this work, we used data from the same model of an aeronautical gas turbine, but three different versions and two power regimes. Pressure, temperature and air and fuel flow data, as well as fuel characterization, enabled numerical simulation of the open Brayton cycle using Matlab software. The results obtained give access to essential information for the complete study of the energy and exergetic efficiencies of each component of the aeronautical gas turbine models studied. The dissertation aims to identify and understand the differences in performance of each module for each power scheme and version chosen. The results were confirmed from a comparison with the results obtained from the literature.