In this study, a system-oriented framework is presented for the conceptual design and performance evaluation of a lightweight fixed-wing unmanned aerial vehicle (dron), in which the systems engineering V-model is integrated with Axiomatic Design. The main objective is to investigate the effect of the design method on system performance, requirements traceability, and the degree of design coupling under identical mission conditions. For this purpose, four strategies, including the conventional analytical method, XFLR5-based analysis design, V-model-based design, and the integrated V-model and Axiomatic Design approach, were compared. The designs were evaluated based on indicators including mass, range, flight endurance, maximum lift-to-drag ratio, estimated cost, and coupling index. After normalization, these indicators were compared using a multi-criteria radar chart. The results showed that the integrated V-model and Axiomatic Design framework, compared with the baseline configuration, led to drag reduction and relative improvement in aerodynamic performance; approximately an 8% reduction in drag was observed compared with the baseline configuration. Furthermore, the coupling index, defined as the mean absolute value of the off-diagonal elements of the design matrix, was obtained to be approximately 0.03 for the integrated method, indicating a structure close to an uncoupled design. The mission analysis also showed that this method creates a suitable balance among performance, cost, and mission requirements. Overall, the results indicate that integrating the V-model with Axiomatic Design provides a traceable and decision-support framework for comparing and selecting conceptual design methods for lightweight fixed-wing drons.