Comparison of Flight Performance Predictions and Tests

This thesis paper discusses the flight performance predictions and experimental data of the solar-powered aircraft, CREATeV that is designed for long-endurance missions. The primary objective of this study is to investigate the effect of different aircraft configurations on the aircraft's endurance and flight conditions. The study analyzes the flight performance of CREATeV using two different airfoils with a total of 9 different configurations, and the results provide recommendations for enhancing the aircraft's endurance in future missions. The procedure involves collecting airfoil data from X-Foil, preparing the input file for FreeWake, obtaining performance and trim results from the software, validating the results using experimental data and performing a comparative analysis of the various configurations. This paper presents results and discussions on the validation of experimental and theoretical data for the RAALB airfoil with free transition. In addition to that, the study conducts three main analyses, namely comparing various airfoil configurations, examining the effect of static margin, and investigating the impact of upward aileron deflection. The results, which were post-processed using MATLAB, show that the experimental and theoretical data are very similar, with certain anomalies expected due to weather conditions. The paper also includes plots that show the total drag, power required, induced drag profile drag, lift coefficient and drag coefficient for the aircraft at a range of angle attacks. Finally, the study explored various design changes that could improve the endurance of an aircraft. The findings suggest that the use of a George airfoil with long span and a center of gravity located at 0.175 m (6.25% static margin) can result in a significant reduction in power required of about 10.7%. In addition to that his study found that deflecting the aileron upwards can reduce drag. These findings suggest that implementing this technique may have potential benefits in terms of improving aircraft performance.