Introduction: Aircraft performance estimation is an essential process during aircraft design for both engineers and aeronautical students. The design process starts from choosing the main aircraft configurations such as dimensions, weight, wing positioning, airfoils, etc., in addition to the power plant specifications. The aircraft performance will then be calculated based on these assumed configurations with each other, the results express the assumed aircraft capabilities and limitations such as minimum and maximum speed, altitude, range and endurance. Based on these results, the assumed configurations could be accepted, or could be modified and then perform the analysis again. Normally, many configurations suggested and calculated till reaching an optimum design that satisfy the required performance demands. Due to the complications of the estimation equations, and the iterative nature of the process; that demands a lot of time and effort; computerized solutions are always suggested. There are several available solutions with different capabilities, yet; most of the available solutions are either commercial solutions not affordable by students; or written in an outdated programming language such as FORTRAN and cause many compatibility issues. There are, as well, free solutions but they are limited to specific types of aircrafts, others are sophisticated and only aerospace specialist can use. Hence the effort to provide an open-source user-friendly aircraft performance software comes in place. UPA* is an open-source easy-to-use computer program using MATLAB developed in Gaziantep University as an easy tool to aircraft designers and students, that will aid them in making design decisions that leads to required performance, as well as, it can be used as educational software for aeronautical students to be used aircraft performance curricula such as Flight Mechanics (AE 304). Aim: The purpose of this paper is to validate the results of UPA using case-study for commercial aircraft. The validation process aims to measure the accuracy of results. By validating the UPA outputs allowing other students in Turkish universities and other aeronautical students to adapt the results of UPA in their researches and designs. Scope: This study will conduct validation for aircraft performance for commercial aircraft with jet population system. The validation is determined with comparison of results obtained from UPA and results published by the manufacturer of the aircraft. The performance parameters are: flight ceiling, stall speed, range, endurance. Other results obtained from the software are also available for further validation. Limitation: The validation included one case study of fixed-wing commercial jet aircraft. Inputs can vary from real aircraft parameters due to lack of accurate source of information such as wind-tunnel inputs. Method: The validation processes run via imitation of aircraft design processes, where aircraft design inputs are determined; so the software can provide the performance of this aircraft. Since the aircraft is already existed; so the results should match the aircraft performance published from the manufacturer. To validate the UPA results, a commercial jet aircraft is selected. The aircraft design inputs/outputs are determined based on UPA input file. Some of the inputs are available by the aircraft manufacturer, while others are available from researchers’ books and papers. Based on the complete list of inputs, the program has been run to analyze the performance of the aircraft. The resulted parameters and diagrams then compare with aircraft manufacturer published capabilities and limitations. Result: The UPA software obtained results are valid results in comparison to the aircraft published per aircraft manufacturer. In an acceptable range of approximation due to the inputs accuracy approximation, and mathematical model approximation. Conclusion: The aircraft performance calculation is complicated and time-consuming process. For that; many computerizing salutations have been developed. Most available software are costly commercial software; thus not accessible by students, or written in FORTRAN and cannot be developed easily. UPA is an open-source MATLAB program developed in Gaziantep University that calculate the aircraft performance parameters. The results of this software have been validated via case-study of fixed-wing jet aircraft; that shows software results can be adopted with acceptable approximation. Students and aircraft-designers in Turkey and outside can use this software for designing and learning objectives. The software requires further development and further validation to include other types and show more results.

Anahtar Kelimeler: Aircraft Design, Aircraft Performance, Open-Source Software, UPA-Gaziantep