Wind-Tunnel Tests of Two Tapered Wings with Straight Trailing Edges and with Constant-Chord Center Sections of Different Spans

Abstract : Tests were made in the NACA 19-foot pressure tunnel to determine the aerodynamic characteristics of two tapered wings having NACA 230-series airfoil sections, constant-chord center sections, and straight trailing edges. The wing spans, the areas, and the root chords of the two wings were equal; the span of the center section of one wing was equal to the root chord and the span of the other was twice the root chord. Lift, drag, and pitching-moment characteristics of the wings with partial-span and full-span split flaps are given for a test Reynolds number of 4,600,000. The maximum lift coefficients of the wing with the square center section were greater, for all arrangements tested, than those of the wing with the rectangular center section; also, with flaps neutral the drag coefficients were smaller for lift coefficients greater than 0.1. The aerodynamic-center positions of the plain wings were found to be 0.451 of the mean chord from the leading edge for the wing with the square center section and 0.442 of the mean chord from the leading edge for the wing with the rectangular center section.