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In this paper, a C-programming code is produced to introduce the best propulsion system including an internal combustion engine combined with turbochargers. Because the power of internal combustion engine will reduce as the altitude increasing, it is required to use one or more turbochargers in order to compensate the loss of power which is caused by reduced ambient air pressure. For this purpose, a code is written that will be able to introduce the best turbochargers combination including intercoolers, according to the target power and the desired altitude of the UAV flight. In other words, input required parameters of the code is the target power of the engine and desired altitude of flight and output of the code is number and characteristics of the turbochargers with their exact manufacturing company names and also the number of intercoolers required for best performance of propulsion system. It should be noted that, if the turbochargers that is chosen by the program are not available, user can select of the similar turbochargers with similar characteristics without any significant difference in performance of the propulsion system.