Investigation of a Morphable Parawing for Unmanned Aerial Vehicle Application

Abstract

A low-speed wind-tunnel investigation is presented characterizing the performance of dual-lobed parawings. Parawings are conically shaped geometries that possess significant washout and camber variation across the span. A series of models with a planar leading-edge sweep of 55 deg increasing to 65 deg to form the parawing canopy were tested. Asymmetric wing tests were also conducted to explore the ability of the configurations to generate moments suitable for roll control. The results indicate a significant reduction in lift with increasing wing slackness stemming from both a reduction in the lift curve slope and positive shift in the zero-lift angle of attack. The angle of attack for zero lift is shown to correlate strongly with the peak lobe height. Asymmetric wing setting showed the generation of rolling moments comparable in magnitude with those produced by traditional ailerons. Numerical simulation indicated that a freely available lifting-surface theory application is able to accurately simulate the performance of the parawing geometry.