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A scissor wing configuration, consisting of four adjustable wing surfaces, is compared with a comparable fixed wing baseline configuration. Wave drag, induced drag, viscous drag, thrust required, and gust loading are calculated for both configurations. The scissor wing is shown to have lower zero lift wave drag and higher total lift to drag ratios than the baseline. It is demonstrated that the scissor configurations' sweep can be programmed to keep the static margin fixed. Thrust required for both the fixed static margin case and a constant sweep angle case are presented with the scissor configuration requiring lower thrust levels. The gust loading ratio of the scissor wing to the baseline is also shown to be significantly less than 1.0 for sweep angles greater than 20 degrees.

A non-linear thin vortex lattice method, BSAERO, with wake rollup has been used to analyze closely coupled generic dual wings. These induced drag studies involved using generic mean camber line wings created using two parabolas. Using this parabola method the location of maximum camber and the magnitude of the maximum camber were varied independently of one another. CL/CDi was used as the success parameter for a particular wing system configuration. The best dual wing geometry configuration had a CL/CDi 18% greater than the comparable dual baseline with symmetric wings. The worst dual wing configuration had a CL/CDi which was 63% below the dual wing baseline. Systematic result are presented which will demonstrate trends as well as magnitudes for the best types of dual wing configurations for minimum induced drag.

Wing tip sails were investigated to determine potential aerodynamic improvements for a wing having an aspect ratio of 10 and a taper ratio of 0.43. The airfoil section used for the wing was an NLF- 0215 and the wing tip was rounded. Three tip sails were utilized for all investigations with each tip sail having a root chord that was 20 percent tip chord of the wing. The wing sails were mounted at the tip of the wing along the chord line. Looking along the span towards the wing root the orientation of each sail tip was the same as the wing tip. Initial studies used sails constructed from two Wortman airfoils. A generic cambered tip-sail was also investigated. Individual sail angle of attack as well as sail dihedral and anhedral were investigated. PMARC, an aerodynamic paneling code was used to predict lift, induced drag, and viscous drag with the use of a momentum integral analysis. All viscous predictions were calculated for a Re/foot = 2.19 × 106.