## 4 Conclusions  
Based on the successful aerodynamic and structural analyses conducted in previous studies, the present work aimed to experimentally validate the obtained numerical results and therefore develop a practical model of the proposed morphing designs: the seamless morphing trailing Edge (SMTE) flap and the elephant trunk mechanism (ETM). The final stage of this project involved prototyping and testing the feasibility of the SMTE flap and the ETM-based actuation system, resulting in the development of a morphing trailing edge flap for the UAS-S45 wing. The prototyping process comprised multiple stages, including the 3D printing of the wing box and the ETMs, integration of the actuation system within the wing structure, attachment of the silicone rubber flexible skin to the SMTE flap and the development of a control system using a graphical user interface (GUI). A series of tests were conducted to assess the feasibility and reliability of various structural components. These tests included individual ETM evaluations, transition section tests and flexible skin assessments prior to full-wing assembly. Upon successful completion of these tests, the design's reliability and practicality were confirmed. The experimental results validated the smooth deformability of the ETMs and of the transition sections, aligning with the numerical findings from previous structural analyses. Additionally, a key issue identified in prior studies--skin buckling on the lower flap surface--was effectively mitigated by employing a pre-tensioning tool to stretch the skin before attachment. To further enhance the performance, flexible rubber connectors were introduced in the transition sections to minimize stress concentrations along the flap's solid edges. Following its full assembly, the morphing wing model underwent wind tunnel testing. A total of 11 tests were conducted, varying both the angle of attack and flap deflection angles. To complement these experiments, Computational Fluid Dynamics (CFD) simulations were performed under identical flight conditions, test constraints and parameters. The lift coefficient (C\({}_{\text{L}}\)) and drag coefficient (C\({}_{\text{D}}\)) obtained from CFD closely matched the experimental results, with maximum discrepancies of 4.06% and 7.3%, respectively. These variations are within acceptable ranges and underscore the reliability of the numerical models. This strong agreement with experimental data confirmed the validity of the aerodynamic findings obtained in the previous study. Furthermore, the structural performance of the ETM was quantitatively validated through both numerical and experimental results. Previous structural analyses demonstrated the ETM's ability to achieve a minimum required flap tip deflection of 66 mm. In the wind tunnel experiments, the SMTE flap exhibited a vertical displacement of 30.815 mm. Given that the test model was constructed at 46.6% of the full-scale size, this measured displacement translates to 66.13 mm in actual scale, thereby confirming the ETM's effectiveness in achieving the target deflection range. This research successfully validated the aerodynamic and structural performance of the proposed morphing wing model. Future studies will focus on exploring additional aerodynamic phenomena, including flow separation, transition and dynamic stall. These aspects will be investigated in wind tunnel experiments using advanced measurement techniques, such as Particle Image Velocimetry (PIV) and smoke injection, further showing the advantages of the SMTE flap design. Conceptualization, M.H.N. ; methodology, M.H.N. ; software, M.H.N. and T.S. ; validation, M.H.N. and T.S. ; formal analysis, M.H.N. and T.S. ; investigation, M.H.N. and T.S. ; resources, M.H.N. ; data curation, M.H.N. and T.S. ; writing--original draft preparation, M.H.N. ; writing--review and editing, M.H.N. and R.M.B. ; visualization, M.H.N. ; supervision, R.M.B. ; project administration, M.H.N. and R.M.B. ; funding acquisition, R.M.B.