22nd Congress of International Council of the Aeronautical Sciences, Harrogate, UK, 28 August - 1st September, 2000
Paper ICAS 2000-7.7.1

AN EXPERIMENTAL STUDY ON WINGTIP DEVICES FOR AGRICULTURAL AIRCRAFT

R. F. F. Coimbra, F. M. Catalano
Aircraft´s Laboratory, University of São Paulo, São Carlos, Brazil

Keywords: experimental study, wingtip devices, agricultural aircraft

The induced drag is responsible for nearly 50% of aircraft total drag and can be reduced through modifications to the wing tip. Some models displace wingtips vortices outwards diminishing the induced drag. Concerning agricultural airplanes, wing tip vortex position is really important, while spreading products over a plantation. In this work, wind tunnel tests were made in order to study the influence in aerodynamic characteristics and vortex position, over Brazilian agricultural aircraft, by the following types of wing tips: delta tip, winglet and down curved. The down curved tip was better for total drag reduction, but not good referring to vortex position. The delta tip gave moderate improvement on aerodynamic characteristic and on vortex position. The winglet had a better vortex position and lift increment, but caused an undesirable result referring to the wing root bending moment. However, winglet showed better development potential for agricultural aircraft.

view full paper