Previous applications have shown that a wingtip treatment on a commercial airliner will reduce drag and increase fuel efficiency, and the most common types of treatment are blended winglets and raked wingtips. With Boeing currently investigating novel designs for its next generation of airliners, a variable geometry raked wingtip novel control effector (VGRWT/NCE) was studied to determine the aerodynamic performance compared to an untreated wingtip. The Boeing SUGAR design employing a truss-braced wing was selected as the baseline. Vortex lattice method (VLM) and computational fluid dynamics (CFD) software was implemented to analyze the aerodynamic performance of such a configuration applied to a next-generation, transonic, mid-range transport aircraft. Several models were created to simulate various sweep positions for the VGRWT/NCE tip, as well as a baseline model with an untreated wingtip. The majority of the investigation was conducted using the VLM software, with CFD used largely as a validation of the VLM analysis. The VGRWT/NCE tip was shown to increase the lift of the wing while also decreasing the drag. The unswept VGRWT/NCE tip increases the amount of lift available over the untreated wingtip, which will be beneficial for take-off and landing. Similarly, the swept VGRWT/NCE tip reduced the drag of the wing during cruise compared to the unmodified tip, which will impact the fuel efficiency of the aircraft. Also, the swept VGRWT/NCE tip showed an increase in moment about a reference axis at 40% of the main wing chord compared to the unmodified wingtip, implying an increase in stability, as well as providing an avenue for roll control and gust alleviation. CFD analysis validated VLM as a useful low fidelity tool that yielded quite accurate results. The main results of this study are tabulated "deltas" in the forces and moments on the VGRWT/NCE tip as a function of sweep angle and tip aileron deflection compared to the baseline wing. A side study of the effects of the joint between the main wing and the movable tip showed that the drag impact can be kept small by careful design of the joint with seals.
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