Unmanned Aerial Vehicles (UAV) have become integral to modern aerial operations, offering versatility in tasks such as surveillance and cargo transport. The blended wing body (BWB) concept represents an innovative geometric design that enhances aerodynamic efficiency and reduces emissions compared to traditional aircraft configurations. CFD simulations are crucial in analysing the impact of BWB geometry on aerodynamic performance, particularly with variations in winglet angles and airflow velocities. This study presents a detailed analysis of winglet design and performance in a BWB UAV, showcasing improvements in lift-to-drag (L/D) ratios and overall aerodynamic efficiencies. Results from numerical simulations demonstrate the significant role of winglet parameters, such as cant angle and angle of attack, in enhancing UAV aerodynamic performance. The study contributes to ongoing advancements in UAV design and optimisation, emphasising the importance of innovative geometric designs and CFD analysis in improving aircraft efficiency and performance.