Aerodynamic Properties of the Inboard Wing Concept

This investigation examines a new concept in airliner configurations from an experimental aerodynamics point of view. The concept proposes mounting the fuselages at the tips of a low aspect ratio wing. The motivation for this configuration is to provide an increase in the number of passengers carried with no increase in span over conventional designs. An additional motivation is the change in the wake flow of the wing, due to the fuselages and vertical tails, which may reduce the effect of the trailing vortex on trailing aircraft. During this investigation, two models of different scales were used to measure the aerodynamic forces and moments of the inboard wing configuration. The tests were conducted in the Virginia Tech 6X6 ft. wind tunnel using a six-component strain gauge balance. The Reynolds number based on chord for the small model was 465,000 and for the large model was 1,225,000. For reference, tests were also conducted with a plain wing having the same span as the full configuration. The L/D values found for this non-optimized configuration were modest compared to those for conventional transports. The vertical tails were shown to act as winglets, reducing drag and increasing L/D. These results suggest areas for substantial improvement in aerodynamic performance of the configuration.