###### Abstract  
This article proposes the integration of structural sizing, topology, and aerodynamic optimization for a morphing variable span of tapered wing (MVSTW) with the aim to minimize its weight. In order to evaluate the feasibility of the morphing wing optimization, this work creates a numerical environment by incorporating simultaneous structural sizing and topology optimization based on its aerodynamic analysis. This novel approach is proposed for an MVSTW. A problem-specific optimization approach to determine the minimum weight structure of the wing components for its fixed and moving segments is firstly presented. The optimization was performed using the OptiStruct solver inside HyperMesh. This investigation seeks to minimize total structure compliance while maximizing stiffness in order to satisfy the structural integrity requirements of the MVSTW. The aerodynamic load distribution along the wingspan at full wingspan extension and maximum speed were considered in the optimization processes. The wing components were optimized for size and topology, and all of them were built from aluminum alloy 2024-T3. The optimization results show that weight savings of up to 51.2% and 55.7% were obtained for fixed and moving wing segments, respectively. Based on these results, the optimized variable-span morphing wing can perform certain flight missions perfectly without experiencing any mechanical failures. s 2021  
under given constraints. Thus, it can determine an optimal structure by finding its optimal load, and therefore, its optimized material distribution. In the TO, when the material density of the design variables is equal to 1, these variables can be considered solid, which is critical for the structural design. On the other hand, when the material density is equal to 0, they can be considered void, thereby determining the best material distribution [8; 9]. Multiple optimization techniques have been used in a variety of engineering design domains, and their application has spread throughout the field of aerospace engineering [10; 11]. For example, several successful optimization techniques for finding the optimal structure of aircraft components are utilized in aircraft design, as seen in [12; 13]. Airbus has applied Topology optimization in the A380 aircraft design program to generate its new lighter aircraft components. The most well-known optimized components for the Airbus A380 are the leading-edge ribs and the fuselage door intercostals, which led to weight savings of approximately 1000 kg for each aircraft [14]. The Boeing company took a similar approach when designing the wings' leading-edge ribs for the B-787 Dreamliner. Topology optimization was incorporated with sizing and shape optimization to find the optimal wing leading-edge shape in the design process. As a result, the leading-edge ribs' weight of the B-787 was reduced by 24-45% compared to the B-777 aircraft [15; 16]. [PERSON] et al. [17; 18] conducted research by combining the results from Computational Fluid Dynamics (CFD) analysis with the Computational Solid Mechanics (CSM) results obtained from Topology optimization. They investigated the aerodynamic load on wing lifting surfaces and used a Solid Isotropic Material with the Penalization (SIMP) topology optimization method to determine a wing's optimal material distribution. The Finite Element Method (FEM) and topology optimization (TO) have been linked with computer-aided engineering (CAE), and they are now considered the most advanced tools and methodologies in the aircraft design field. The combination of the FEM with TO makes it possible to obtain major weight reductions, thus resulting in material and fuel savings while maintaining the final product's robustness properties [19; 20]. Furthermore, optimization methods based on merging CFD with CSM allow the determination of the optimal wing shape, which could decrease the aircraft's weight by obtaining its optimal aerodynamic performance [21].