Measurements of the lift, pitching moment, and pressure distribution of a wing which was swept- -40°, -30°, 0°, 35°, and 45° were made at low speed in a wind tunnel. The wing span was decreased to give aspect ratios of 6.8, 5.3, 4.2, 3.4, and 2.8 with corresponding taper ratios of approximately 0.4 to 0.7. The experimental effects of independent variations of sweep and aspect ratio on the lift—curve slopes, the span load distributions, the aerodynamic—center locations, and the spanwise center of—pressure locations are compared with the effects estimated by use of the Weissinger method-nA sufficient reduction of the aspect ratio of the swept wings eliminated the static longitudinal instability at the moderate to high lift coefficients, but failed to eliminate the premature local stalling associated with swept wings. The Weissinger method gave good agreement with the experimental lift-curve slopes, but slightly underestimated the lift carried over the outer portions of the wings.
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