For the investigation, a simple flying wing model, equipped with the MH 60 airfoil was defined and a three dimensional panel model of the configuration was created (each airfoil section was represented by 60 chordwise panels, spanwise clustering was used to refine the tip and root regions, resulting in about 600 to 800 panels per half wing, depending on the configuration examined). Only the region close to the wing tip was modified, which resulted in four different configurations:

• a rounded wing tip without winglet,
• a winglet with a large, rounded corner,
• a winglet with a sharp corner, and
• a winglet with a sharp corner, but moved downstream 50% of the tip chord. The maximum thickness of the winglet section is approximately located at the trailing edge of the wing tip.

All winglets had the same airfoil as the wing. The following images show the tip region of these four configurations.

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