A study of the finite-span effects on the local loading character-istics of two sweptback wings at low speed has been made with a view toward providing some insight into the usefulness of two-dimensional section data and span-loading theory for determining the characteristics of sections of a swept wing. The two wings considered, for which complete pressure-distribution data were available at large scale, were identical in plan form having 45° of sweepback and an aspect ratio of 6. and differed in twist and in sections, the latter being the NACA 64A010 and NACA 64A8l0.nAt low values of lift coefficient, the finite-span effects are restricted to regions of the wing close to the root and tip. At higher values of lift a three-dimensional viscous effect becomes evident. Examination of this effect reveals that the lateral flow of the boundary-layer air acts as a boundary-layer-control agent over "Virtually the entire span of the wing, alleviating flow separation and thus increasing the local maximum lift coefficient beyond that expected of the section in two-dimensional oblique flow. The effect is greatest near the root, diminishing gradually spanwise in approaching the tip. Near the tip where there is little boundary-layer-control effect the local section characteristics closely resemble those for the two-dimensional section in oblique flow.
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