Experimental and CFD Investigation of Directional Stability of a Box-Wing Aircraft Concept

This study aimed to explore the directional stability issues of a previously studied light box-wing aircraft model with pusher propeller engine in fuselage aft section. Earlier configurations have included use together lifting system consisting two wings joined at their wingtips vertical stabilizers. However, these side surfaces failed provide sufficient stability, thus prompting quest this for novel solutions that would exclude need extension and typical fin. Solutions ducted few small “fishtail” fins, which formed part itself coupled vortex generators on surface improve interference heal flow separation cone. The results wind tunnel testing were supported CFD simulations explain behavior each solutions. Tuft visualization computed patterns allowed identification sources observed low efficiency terms fishtail against simple idle duct without propeller. A final configuration modified version fins was achieved provides enough yaw margins safe flight.