Analysis of Longitudinal Aerodynamic Characteristics of an Aircraft Model with and Without Winglet

This paper describes the influences of two pair of elliptical and circular shaped winglets with the wing of the aircraft model for the reduction of induced drag without increasing the span of the aircraft. Aerodynamic characteristics for the model aircraft wing with NACA section No. 65-3-218 with and without elliptical and circular winglets have been studied using a subsonic wind tunnel of 1m × 1m rectangular test section. Lift and drag measurements are carried out using a six component external balance. Tests are carried out on the aircraft model with and without winglet at the Reynolds numbers 0.17×10^6, 0.21×10^6 and 0.25×10^6. The experimental results show that lift curve slope increases by 1-6% with the addition of certain winglet configurations and at the same time, the drag decreases by 20-28% as compared to the aircraft model with and without winglet for the maximum Reynolds number considered in the present study. The experimental approach and a summary of the main findings are presented.