Journal of Technology in Aerospace Engineering

Journal of Technology in Aerospace Engineering

Development of Computer Code for the Evaluation of GA Aircraft Controllability and Stability Based on CS-23 Regulations

Document Type : Research Article

Authors
Seyyedeh Marzieh Mousavi 1
Iman Bahman Jahromi 2
Jamshid Fazilati 3
1 Department of Aerospace Engineering,, Amirkabir University of Technology, Tehran, Iran
2 Aerospace Research Institute, Ministry of Science Research, and Technology, Tehran, Iran
3 Aerospace Research Institute, Ministry of Science Research and Technology, Tehran, Iran
10.22034/jtae.2026.10.2.5
Abstract
In this study, a comprehensive and automated computer code for evaluating controllability and stability of general aviation aircraft is presented. The calculations are based on the Roskam method, and the results have been aligned with the requirements of CS23 regulation. In this system, all necessary charts are automatically generated using polynomial fittings as well as neural networks, eliminating the need for manual extraction of values. Additionally, the lift and drag coefficients are computed using the panel method, and the computational procedure for all static and dynamic parameters of a sample model aircraft has been fully implemented and validated against the reference software AAA. One significant advantage of this system compared to AAA is that users have direct access to the source codes and algorithms, enabling modification, development, and localization of the software. Furthermore, a complete user manual and comprehensive documentation are provided to facilitate the use of the system for researchers. A graphical user interface (GUI) has also been developed, allowing users to perform calculations and view results in the form of charts and analytical reports without requiring specialized coding knowledge. To validate the process and calculations, an aircraft (AeroVolga LA-8C) is analyzed. The results indicate that during the takeoff and cruise flight phases, the aircraft’s controllability meets the minimum requirements of CS23 standards, enabling safe and precise maneuvering. Stability analysis also demonstrated stable behavior in these phases, with no critical instabilities observed. Finally, it can be concluded that the examined nominated aircraft has the potential to obtain such certification.
Keywords
Computer Code
Stability
Controllability
Standard
GUI
Subjects
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