Abstract:
The objective of this study was to assess the fly worthiness of a designed target UAV. Initially,
the aircraft was found to be statically longitudinally unstable, but modifications and optimizations
were made to improve its stability. The semi-empirical formulas were used to calculate the moment
contributions of the various components of the unmanned air vehicle, and the results were
visualized through a graph displaying the overall effect of all components. A detailed SolidWorks
model was created to gather the necessary information for the calculation, and the relevant
geometric and aerodynamic properties for longitudinal, lateral, and directional stability were
determined for both static and dynamic scenarios. The approximate model of the UAV was created
using XFLR5 software, from which the necessary graphs and values were obtained. The values
obtained from the semi-empirical formulas and XFLR5 were compared to validate the results. The
final analysis was conducted to ensure the fly worthiness of the designed UAV. As a result, the
optimized model was found statically stable where the moment coefficients were 𝐶𝑚𝛼 < 0 , 𝐶𝑛𝛽 >
0 & 𝐶𝑙𝛽 < 0 . In the dynamic stability part, all parameters were found to be stable except for
the spiral mode. The performance parameters were also calculated for different altitudes and
compared with XFLR5 parameters and the results were satisfactory.
